Semiconductor equipment

Abstract

To provide a semiconductor device that minimizes the increase in the number of masks or the number of manufacturing processes. [Solution] In the semiconductor device 100, transistor Tr1 has a first gate electrode 104, a first insulating film 106 thereon, a first oxide semiconductor film 108 thereon, a source electrode 112a and a first drain electrode 112b thereon, a first oxide semiconductor film, a second insulating film 116 on the first source electrode and the first drain electrode, and a second gate electrode 122c thereon. Second transistor Tr2 has a first drain electrode, a second insulating film on the first drain electrode, a second oxide semiconductor film 128 on the second insulating film, a second source electrode 122a and a second drain electrode 122b thereon, a second oxide semiconductor film, a third insulating film 124, 126 on the second source electrode and the second drain electrode, and a third gate electrode 130 on the third insulating film, and the first oxide semiconductor film and the second oxide semiconductor film have overlapping regions.

Description

[Technical Field]

[0001] One aspect of the present invention is a semiconductor device having an oxide semiconductor film and a display having the semiconductor device. Regarding the device.

[0002] Furthermore, one aspect of the present invention is not limited to the above-mentioned technical field. One aspect of the technical field relates to a product, method, or method of manufacture. Alternatively, the present invention relates to a professional Seth, machine, manufacture, or composition of matter This relates to semiconductor devices, display devices, light-emitting devices, energy storage devices, and memory devices. In particular, one aspect of the present invention relates to semiconductor devices, display devices, light-emitting devices, energy storage devices, and memory devices. This relates to the placement, the driving method thereof, or the manufacturing method thereof.

[0003] In this specification, a semiconductor device is defined as a device that can function by utilizing semiconductor properties. This refers to all types of devices, including semiconductor elements such as transistors, semiconductor circuits, computing devices, and memory devices. The device is a form of semiconductor device. Examples include imaging devices, display devices, liquid crystal display devices, light-emitting devices, and electric devices. Optical devices, power generation devices (including thin-film solar cells, organic thin-film solar cells, etc.), and electronic equipment are subject to the following regulations: It may have a semiconductor device. [Background technology]

[0004] A transistor (field-effect transistor) is formed using a semiconductor thin film on a substrate having an insulating surface. The technology for constructing transistors (FETs, also known as thin-film transistors (TFTs)) is attracting attention. It is anticipated that the transistor will be used in integrated circuits (ICs) and image display devices (display devices), etc. It is widely applied in electronic devices. Silicon is a semiconductor thin film applicable to transistors. While semiconductor materials such as crystalline silicon are widely known, oxide semiconductors are attracting attention as other materials. It is being watched.

[0005] For example, Patent Document 1 describes a first transistor using an oxide semiconductor film and an oxide semiconductor By stacking a second transistor using a body membrane, multiple memory cells can be superimposed. A technology for reducing cell area has been disclosed.

[0006] Furthermore, Patent Document 2 describes a pixel section having multiple pixels arranged in two dimensions, and multiple pixels It comprises a drive circuit section for driving the display, a first layer including the drive circuit section, and a second layer including the pixel section. By stacking the components, the space required for the drive circuit in the peripheral area of ​​the pixel is reduced. The technology has been disclosed. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2013-138191 [Patent Document 2] Japanese Patent Publication No. 2015-194577 [Overview of the project] [Problems that the invention aims to solve]

[0008] As shown in Patent Documents 1 and 2, by stacking multiple transistors, the transistors The footprint can be reduced. On the other hand, stacking multiple transistors allows for mass There were problems such as an increase in the number of sheets or processes.

[0009] In view of the above problems, one aspect of the present invention relates to a semiconductor device in which a plurality of transistors are stacked. Therefore, one of the challenges is to provide a semiconductor device that minimizes the increase in the number of masks or the number of manufacturing processes. Alternatively, one aspect of the present invention involves stacking a plurality of transistors having oxide semiconductor films. To provide a semiconductor device that minimizes the increase in the number of masks or the number of manufacturing processes. This is one of the challenges. Alternatively, one aspect of the present invention aims to provide a novel semiconductor device. Let's make this one of the topics.

[0010] Furthermore, the description of the above problems does not preclude the existence of other problems. The approach does not necessarily need to solve all of these problems. Other problems are addressed in the details. This will become clear from the descriptions in the documents, etc., and it is not possible to extract any issues other than those mentioned above from the descriptions in the specifications, etc. It is possible to release it. [Means for solving the problem]

[0011] One aspect of the present invention relates to a semiconductor device having a first transistor and a second transistor. The first transistor is configured such that it has a first gate electrode and a first on the first gate electrode An insulating film, a first oxide semiconductor film on the first insulating film, and a first oxide semiconductor film on the first oxide semiconductor film Source electrode, first drain electrode on first oxide semiconductor film, first oxide semiconductor film , a first source electrode, and a second insulating film on the first drain electrode, and the second insulating film on the second The second transistor has two gate electrodes and a first drain electrode and a first drain electrode. A second insulating film on the in electrode, a second oxide semiconductor film on the second insulating film, and a second oxide A second source electrode on a semiconductor film, a second drain electrode on a second oxide semiconductor film, and A third insulating film on two oxide semiconductor films, a second source electrode, and a second drain electrode, A third gate electrode on a third insulating film, comprising a first oxide semiconductor film and a second oxide A semiconductor film is a semiconductor device that has overlapping regions.

[0012] Another aspect of the present invention comprises a first transistor and a second transistor. A semiconductor device wherein the first transistor comprises a first gate electrode and a first gate electrode The first insulating film on top, the first oxide semiconductor film on the first insulating film, and the first oxide semiconductor film The first source electrode on top, the first drain electrode on the first oxide semiconductor film, and the first oxide A semiconductor film, a first source electrode, and a second insulating film on the first drain electrode, and a second insulating film on the first drain electrode The second transistor has a second gate electrode on the edge film, and a third gate electrode on the first insulating film. A gate electrode, a second insulating film on the third gate electrode, and a layer formed on the second insulating film. A second oxide semiconductor film having a channel region, a source region, and a drain region, and a channel A third insulating film in contact with the region, a fourth gate electrode in contact with the third insulating film, and a source region, A drain region, a fourth insulating film in contact with the fourth gate electrode, and a source region electrically connected A second source electrode is connected to the drain region, and a second drain electrode is electrically connected to the drain region. The first oxide semiconductor film and the second oxide semiconductor film have overlapping regions. It is a semiconductor device.

[0013] Furthermore, in the above embodiment, the first gate electrode and the second gate electrode are made of the first insulating film and and connected at an opening provided in the second insulating film, and on the side of the first oxide semiconductor film It is preferable to have a region located outside the edge.

[0014] Furthermore, in the above embodiment, either the first oxide semiconductor film or the second oxide semiconductor film One or both contain In, Zn, and M (where M is Al, Ga, Y, or Sn). It would be preferable if that were the case.

[0015] Furthermore, in the above embodiment, the ratio of the number of atoms of In, M, and Zn is In:M:Zn=4: If it is a 2:3 neighborhood and In is 4, then M is between 1.5 and 2.5, and Zn is 2 or less. It is preferable if the score is 4 or lower.

[0016] Furthermore, in the above embodiment, either the first oxide semiconductor film or the second oxide semiconductor film Preferably, one or both of the materials have crystalline portions, and the crystalline portions have c-axis orientation.

[0017] Another aspect of the present invention includes a first transistor and a second transistor. A semiconductor device wherein the first transistor comprises a first oxide semiconductor film and a first oxide semiconductor film. A first insulating film on a conductive film and a region overlapping with the first oxide semiconductor film with the first insulating film in between. A first conductive film having a region, and a second insulating film on the first oxide semiconductor film and on the first conductive film A border film, a second conductive film on the first oxide semiconductor film, and a third conductive film on the first oxide semiconductor film The dielectric film and the third insulating film on the first oxide semiconductor film, the second conductive film, and the third conductive film. The first oxide semiconductor film has a channel region in contact with the first insulating film and a second insulating film. It has a source region in contact with the edge film and a drain region in contact with the second insulating film, and the second trap The converter consists of a third conductive film, a third insulating film on the third conductive film, and a second insulating film on the third insulating film. an oxide semiconductor film, a fourth conductive film on the second oxide semiconductor film, and the second oxide semiconductor film The first oxide semiconductor film and the second oxide semiconductor film are mutually connected, and the fifth conductive film is located above, and the first oxide semiconductor film and the second oxide semiconductor film are mutually connected. This is a semiconductor device that has an overlapping region.

[0018] Another aspect of the present invention includes a first transistor and a second transistor. A semiconductor device wherein the first transistor comprises a first oxide semiconductor film and a first oxide semiconductor film. A first insulating film on a conductive film and a region overlapping with the first oxide semiconductor film with the first insulating film in between. A first conductive film having a region, and a second insulating film on the first oxide semiconductor film and on the first conductive film A border film, a second conductive film on the first oxide semiconductor film, and a third conductive film on the first oxide semiconductor film The dielectric film and the third insulating film on the first oxide semiconductor film, the second conductive film, and the third conductive film. The first oxide semiconductor film has a channel region in contact with the first insulating film and a second insulating film. It has a source region in contact with the edge film and a drain region in contact with the second insulating film, and the second trap The converter consists of a third conductive film, a third insulating film on the third conductive film, and a second insulating film on the third insulating film. an oxide semiconductor film, a fourth conductive film on the second oxide semiconductor film, and the second oxide semiconductor film The fifth conductive film on top, the second oxide semiconductor film, the fourth conductive film, and the fourth conductive film on the fifth conductive film The insulating film and the second oxide semiconductor film have a region that overlaps with the second oxide semiconductor film, with a fourth insulating film in between. The device has 6 conductive films, and the first oxide semiconductor film and the second oxide semiconductor film overlap each other. This is a semiconductor device having a region.

[0019] Another aspect of the present invention includes a first transistor and a second transistor. A semiconductor device wherein the first transistor comprises a first oxide semiconductor film and a first oxide semiconductor film. A first insulating film on a conductive film and a region overlapping with the first oxide semiconductor film with the first insulating film in between. A first conductive film having a region, and a second insulating film on the first oxide semiconductor film and on the first conductive film A border film, a second conductive film on the first oxide semiconductor film, and a third conductive film on the first oxide semiconductor film The dielectric film and the third insulating film on the first oxide semiconductor film, the second conductive film, and the third conductive film. The first oxide semiconductor film has a channel region in contact with the first insulating film and a second insulating film. It has a source region in contact with the edge film and a drain region in contact with the second insulating film, and the second trap The converter consists of a third conductive film, a third insulating film on the third conductive film, and a second insulating film on the third insulating film. an oxide semiconductor film, a fourth conductive film on the second oxide semiconductor film, and the second oxide semiconductor film The fifth conductive film on top, the fourth insulating film on the second oxide semiconductor film, and the fourth insulating film sandwiched in between. Then, a sixth conductive film having a region overlapping with the second oxide semiconductor film, and the second oxide semiconductor The second oxide semiconductor film has a fifth insulating film on the film and on the sixth conductive film, and the second oxide semiconductor film is a fourth A channel region in contact with the insulating film, a source region in contact with the fifth insulating film, and a channel region in contact with the fifth insulating film The first oxide semiconductor film and the second oxide semiconductor film have a drain region and are mutually connected. This is a semiconductor device that has an overlapping region.

[0020] In each of the above configurations, either the first oxide semiconductor film or the second oxide semiconductor film. Alternatively, both may have In, M (where M is Al, Ga, Y, or Sn), and Zn. preferable.

[0021] Furthermore, in each of the above configurations, the ratio of the number of In, M, and Zn atoms is In:M:Zn=4 :2:3 neighborhood, if In is 4, then M is between 1.5 and 2.5, and Zn is 2 Preferably, the number is 4 or less.

[0022] Furthermore, in each of the above configurations, either the first oxide semiconductor film or the second oxide semiconductor film Preferably, one or both of the materials have a crystalline portion, and the crystalline portion has c-axis orientation.

[0023] Another aspect of the present invention is a semiconductor device described in any one of the above aspects, and a light-emitting element It is a display device having a child and a light-emitting element, and the light-emitting element has an organic compound, and the organic compound It is preferable that it contains a polymer compound.

[0024] Another aspect of the present invention is a display module having the above-mentioned display device and a touch sensor. Furthermore, another aspect of the present invention is a semiconductor device described in any one of the above aspects. An electronic device having the above-mentioned display device or the above-mentioned display module and operation keys or a battery It is a vessel. [Effects of the Invention]

[0025] According to one aspect of the present invention, in a semiconductor device in which multiple transistors are stacked, a mask It is possible to provide a semiconductor device with a small increase in the number or number of processes. Or, one of the present inventions Depending on the embodiment, in a semiconductor device in which a plurality of transistors having an oxide semiconductor film are stacked, This allows for the provision of semiconductor devices with a small increase in the number of masks or processing steps. Or, According to one aspect of the present invention, a novel semiconductor device can be provided.

[0026] Furthermore, the description of these effects does not preclude the existence of other effects. One embodiment does not necessarily have to possess all of these effects. Furthermore, other effects may be considered. This will become clear from the description in the specification, drawings, claims, etc., and the specification, drawings It is possible to extract effects other than those mentioned above from the descriptions in the surfaces, claims, etc. [Brief explanation of the drawing]

[0027] [Figure 1] A diagram illustrating the top surface and cross-section of a semiconductor device. [Figure 2] A diagram illustrating the circuitry of a semiconductor device. [Figure 3] A diagram illustrating the cross-section of a semiconductor device. [Figure 4] A diagram illustrating the cross-section of a semiconductor device. [Figure 5] A diagram illustrating the cross-section of a semiconductor device. [Figure 6] A diagram illustrating the cross-section of a semiconductor device. [Figure 7] A diagram illustrating energy bands. [Figure 8] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 9] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 10] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 11] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 12] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 13] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 14] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 15] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 16] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 17] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 18] A diagram illustrating the top surface and cross-section of a semiconductor device. [Figure 19] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 20] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 21] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 22] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 23] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 24] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 25] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 26] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 27] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 28] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 29] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 30] A diagram illustrating the top surface and cross-section of a semiconductor device. [Figure 31] A diagram illustrating the circuitry of a semiconductor device. [Figure 32] A diagram illustrating the cross-section of a semiconductor device. [Figure 33] A diagram illustrating the cross-section of a semiconductor device. [Figure 34] A diagram illustrating the cross-section of a semiconductor device. [Figure 35] A diagram illustrating energy bands. [Figure 36] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 37] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 38] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 39] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 40] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 41] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 42] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 43] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 44] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 45] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 46] A diagram illustrating the top surface and cross-section of a semiconductor device. [Figure 47] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 48] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 49] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 50] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 51] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 52] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 53] A top view and a cross-sectional view illustrating the method for manufacturing a semiconductor device. [Figure 54] Schematic cross-sectional view of a light-emitting element. [Figure 55] A schematic cross-sectional diagram illustrating the method for fabricating the EL layer. [Figure 56] A conceptual diagram illustrating a droplet dispensing device. [Figure 57] A diagram illustrating the range of atomic ratios in oxide semiconductors. [Figure 58] A diagram illustrating the crystal structure of InMZnO4. [Figure 59] A diagram illustrating the energy bands in a transistor that uses an oxide semiconductor in the channel region. [Figure 60] A diagram illustrating the XRD structural analysis of CAAC-OS and single-crystal oxide semiconductors, and a diagram showing the limited-field electron diffraction pattern of CAAC-OS. [Figure 61] Cross-sectional TEM images of CAAC-OS, as well as planar TEM images and their image analysis results. [Figure 62]Figure showing the electron diffraction pattern of nc-OS, and a cross-sectional TEM image of nc-OS. [Figure 63] Cross-sectional TEM image of an a-like OS. [Figure 64] A diagram showing the changes in the crystalline structure of In-Ga-Zn oxide due to electron irradiation. [Figure 65] A top view showing one embodiment of a display device. [Figure 66] A cross-sectional view showing one embodiment of a display device. [Figure 67] A cross-sectional view showing one embodiment of a display device. [Figure 68] A block diagram illustrating the display device. [Figure 69] A diagram illustrating the display module. [Figure 70] A diagram illustrating electronic devices. [Figure 71] A diagram illustrating electronic devices. [Figure 72] A perspective view illustrating the display device. [Modes for carrying out the invention]

[0028] The embodiments will be described below with reference to the drawings. However, many embodiments are described. It can be implemented in different ways, without deviating from its purpose and scope. Those skilled in the art will readily understand that the form and details can be modified in various ways. Therefore, the present invention This shall not be interpreted as being limited to the contents described in the following embodiments.

[0029] Furthermore, in the drawings, the size, layer thickness, or area is exaggerated for clarity. There are cases where this is not the case. Therefore, it is not necessarily limited to that scale. Note that the drawing is an ideal example. This is a schematic representation and is not limited to the shapes or values ​​shown in the drawings.

[0030] Furthermore, the ordinal numbers "1st," "2nd," and "3rd" used in this specification refer to the constituent elements. This note is added to avoid confusion and does not imply any numerical limitation.

[0031] Furthermore, in this specification, phrases indicating placement such as "above" and "below" refer to the relative positions of the components. The positional relationships are used for convenience in explaining them by referring to the drawings. The relationship changes as appropriate depending on the direction in which each component is described. Therefore, as explained in the specification... It is not limited to the same words or phrases, and can be appropriately rephrased depending on the situation.

[0032] Furthermore, in this specification, the term "transistor" includes a gate, a drain, and a source. It is an element having at least three terminals. And, drain (drain terminal, drain Between the drain region (or drain electrode) and the source (source terminal, source region, or source electrode) It has a channel region, and current flows through the drain, the channel region and the source. This is possible. In this specification, the channel region is defined as the region where the current is mainly It refers to the area in which something flows.

[0033] Furthermore, the source and drain functions may differ when using transistors with different polarities, or when the circuit The direction of the current may change during operation, which can cause the current to switch positions. In detailed documents, the terms "source" and "drain" may be used interchangeably. ru.

[0034] Furthermore, in this specification, etc., "electrically connected" means "having some kind of electrical effect." This includes cases where the connection is made via ". Here, "has some electrical effect The term "of" is not particularly limited as long as it enables the exchange of electrical signals between connected objects. For example, "things that have some kind of electrical effect" include electrodes and wiring, as well as transistors. Switching elements such as resistors, inductors, capacitors, and other various functional elements are available. This includes elements such as [specific components].

[0035] Furthermore, in this specification, "parallel" means that two straight lines have an angle of -10° or more and 10° or less. This refers to a state where objects are arranged in degrees. Therefore, it also includes cases where the angle is between -5° and 5°. Furthermore, "perpendicular" refers to a state in which two straight lines are positioned at an angle of 80° to 100°. Therefore, this includes cases where the angle is between 85° and 95°.

[0036] Furthermore, in this specification, the terms "membrane" and "layer" are interchangeable. It is possible to change the term. For example, the term "conductive layer" can be changed to the term "conductive film." It may be possible to change it. Or, for example, change the term "insulating film" to "insulating layer". In some cases, it may be possible to change the terminology to this.

[0037] Furthermore, unless otherwise specified in this specification, off-current refers to the current when the transistor is turned off. This refers to the drain current when the device is in a state (also called a non-conductive state or an interrupted state). Unless otherwise specified, in an n-channel transistor, the voltage between the gate and source is V When gs is lower than the threshold voltage Vth, in a p-channel transistor, the gate and socket are... This refers to a state where the voltage Vgs between channels is higher than the threshold voltage Vth. For example, n channels. The off-current of a transistor is defined as the voltage between the gate and source (Vgs) and the threshold voltage (Vt). Sometimes, this refers to the drain current when it is lower than h.

[0038] The off-current of a transistor may depend on Vgs. Therefore, when it is said that the off-current of the transistor is I or less, it may mean that there exists a value of Vgs for which the off-current of the transistor becomes I or less. The off-current of a transistor may refer to the off-current in the off-state at a given Vgs, in the off-state at Vgs within a given range, or in the off-state at Vgs where a sufficiently reduced off-current is obtained, etc. For example, when the threshold voltage Vth is 0.5V, the drain current at Vgs = 0.5V is -9 A, the drain current at Vgs = 0.1V is -1 A, the drain current at Vgs = -0.5V is 3 A, and the drain current at Vgs = -0.8V is -19 A, consider an n-channel transistor. Since the drain current of this transistor is -22 A or less at Vgs = -0.5V or in the range of Vgs from -0.5V to -0.8V, it may be said that the off-current of this transistor is -19 A or less. Since there exists a Vgs for which the drain current of this transistor becomes -19 A or less, it may be said that the off-current of this transistor is -22 A or less. The off-current of a transistor may refer to the off-current in the off-state at a given Vgs, in the off-state at Vgs within a given range, or in the off-state at Vgs where a sufficiently reduced off-current is obtained, etc. The off-current of a transistor may refer to the off-current in the off-state at a given Vgs, in the off-state at Vgs within a given range, or in the off-state at Vgs where a sufficiently reduced off-current is obtained, etc. The off-current of a transistor may refer to the off-current in the off-state at a given Vgs, in the off-state at Vgs within a given range, or in the off-state at Vgs where a sufficiently reduced off-current is obtained, etc.

[0039] As an example, assume a threshold voltage Vth of 0.5V, a drain current of -9 A at Vgs = 0.5V, a drain current of -1 A at Vgs = 0.1V, a drain current of 3 A at Vgs = -0.5V, and a drain current of -19 A at Vgs = -0.8V for an n-channel transistor. -9 A, and the drain current at Vgs = 0.1V is -1 A. -1 3 3 A, and the drain current at Vgs = -0.5V is -19 A. -19 A, and the drain current at Vgs = -0.8V is -22 A for an n-channel transistor. -22 -22 A for an n-channel transistor. Since the drain current of this transistor is -22 A or less at Vgs = -0.5V or in the range of Vgs from -0.5V to -0.8V, it may be said that the off-current of this transistor is -19 A or less. -19 -19 A or less at Vgs = -0.5V or in the range of Vgs from -0.5V to -0.8V, it may be said that the off-current of this transistor is -19 A or less. -19 -19 A or less, it may be said that the off-current of this transistor is <0 by the fact that there exists a Vgs for which the drain current of this transistor becomes -19 A or less, it may be said that the off-current of this transistor is -22 A or less. -19 -22 -22 -22 -22 A or less.

[0040] Also, in this specification, etc., the off-current of a transistor having a channel width W may be represented by the current value flowing per channel width W. Also, at a given channel width (for example, 1μm), It is sometimes expressed as the value of the current flowing through it. In the latter case, the unit of off-current is the second of current / length. It may be expressed in units that have an element (for example, A / μm).

[0041] The off-current of a transistor may be temperature-dependent. In this specification, the off-current Unless otherwise specified, the device is turned off at room temperature, 60°C, 85°C, 95°C, or 125°C. It may represent electric current. Alternatively, it may indicate that the reliability of the semiconductor device containing the transistor is maintained. The temperature at which the transistor is proven, or the temperature at which the semiconductor device containing the transistor is used (e.g.) For example, it may represent the off-current at any one temperature between 5°C and 35°C. The off-current of the inverter is less than or equal to I, meaning that at room temperature, 60°C, 85°C, 95°C, and 125°C, The temperature at which the reliability of the semiconductor device containing the transistor is guaranteed, or the transistor The temperature at which semiconductor devices containing DISTROs are used (for example, any one temperature between 5°C and 35°C) At a given temperature, there exists a value of Vgs such that the transistor's off-current is less than or equal to I. It may refer to something.

[0042] The off-current of a transistor may depend on the voltage Vds between the drain and source. In this specification, unless otherwise specified, the off-current is defined as Vds = 0.1V, 0.8V, 1V, 1.2V, 1.8V, 2.5V, 3V, 3.3V, 10V, 12V, 16V, and This may represent the off-current at 20V. Or, the semiconductor containing the transistor in question. The reliability of the device, etc., is guaranteed by Vds, or the semiconductor device containing the transistor in question. It may represent the off-current at Vds used in applications such as transistor off-voltage. The current is less than or equal to I, meaning that Vds is 0.1V, 0.8V, 1V, 1.2V, 1.8V, 2.5V, 3V, 3.3V, 10V, 12V, 16V, 20V, the transistor in question The reliability of the semiconductor device is guaranteed by Vds, or the semiconductor device containing the transistor. In devices such as body equipment, the off-current of the transistor at Vds is less than or equal to I. This can sometimes refer to the existence of a value for gs.

[0043] In the above explanation of off-current, drain may be read as source. The term "current" can also refer to the current flowing through the source of a transistor when it is in the off state.

[0044] Furthermore, in this specification, the term "leakage current" may be used interchangeably with "off-current." Furthermore, in this specification, off-current refers to, for example, when a transistor is in the off state. It can also refer to the current flowing between the source and the drain.

[0045] Furthermore, in this specification, the threshold voltage of a transistor refers to the channel of a transistor. This refers to the gate voltage (Vg) when the threshold voltage is formed. Specifically, it is the threshold voltage of the transistor. Voltage is plotted with the gate voltage (Vg) on ​​the horizontal axis and the square root of the drain current (Id) on the vertical axis. In the curve (Vg-√Id characteristic), the straight line obtained by extrapolating the tangent line with the maximum slope is The gate voltage (Vg) at the intersection of the square root of the drain current (Id) and 0 (Id is 0A) is... ) may refer to the threshold voltage of a transistor, where the channel length is L and the channel length is L. Let W be the channel width, and the value of Id[A]×L[μm] / W[μm] is 1×10 -9 [A] It may refer to the gate voltage (Vg).

[0046] Furthermore, even when the term "semiconductor" is used in this specification, for example, if the conductivity is If the value is sufficiently low, it may have the properties of an "insulator". Also, "semiconductor" and " The term "insulator" has an ambiguous boundary and may not be strictly distinguishable in some cases. Therefore, this specification... The term "semiconductor" as used in this document may sometimes be replaced with "insulator." Similarly, this In some cases, the term "insulator" as used in specifications, etc., can be replaced with "semiconductor." In some cases, the term "insulator" as used in this specification may be replaced with "semi-insulator." .

[0047] Furthermore, even when the term "semiconductor" is used in this specification, for example, if the conductivity is If the value is sufficiently high, it may possess the properties of a "conductor." Also, "semiconductor" and " The term "conductor" has an ambiguous boundary and may not be strictly distinguishable in some cases. Therefore, this specification... The term "semiconductor" as used in this document may sometimes be replaced with "conductor." Similarly, this In some cases, the term "conductor" as used in specifications, etc., can be replaced with "semiconductor."

[0048] Furthermore, in this specification, semiconductor impurities refer to components other than the main components that constitute the semiconductor film. For example, elements with a concentration of less than 0.1 atomic percent are considered impurities. Furthermore, DOS (Density of States) is formed in semiconductors, and In some cases, the rear mobility may decrease, or the crystallinity may decrease. When an oxide semiconductor is present, impurities that alter the properties of the semiconductor include, for example, Group 1 impurities. These include elements, Group 2 elements, Group 14 elements, Group 15 elements, and transition metals other than the main component. In addition, hydrogen (also found in water), lithium, sodium, silicon, boron, phosphorus, carbon, Examples include nitrogen. In the case of oxide semiconductors, oxygen deficiency can occur due to the inclusion of impurities such as hydrogen. This can sometimes form. Also, if the semiconductor contains silicon, it can change the properties of the semiconductor. Examples of impurities include, for example, Group 1 elements, Group 2 elements, and Group 13 elements, excluding oxygen and hydrogen. This includes elements from Group 15, among others.

[0049] (Embodiment 1) In this embodiment, a semiconductor device and a method for manufacturing a semiconductor device according to one aspect of the present invention are described below. This will be explained with reference to Figures 1 through 17.

[0050] <1-1. Example of Semiconductor Device Configuration 1> Figure 1(A) is a top view of a semiconductor device 100 according to one embodiment of the present invention, and Figure 1(B) is a top view of a semiconductor device 100 according to one embodiment of the present invention. This corresponds to the cross-sectional view of the section between the dashed line A1-A2 shown in 1(A). Note that Figure 1( B) shows the cross-section of transistor Tr1 in the direction of the channel length (L), and transistor Tr2. Includes a cross-section in the direction of the channel length (L).

[0051] Furthermore, in Figure 1(A), in order to avoid complexity, the configuration of the semiconductor device 100 is shown. Some of the elements (such as insulating films that function as gate insulating films) and some of the symbols of the components are omitted. This is illustrated in the diagram. Note that in the top view of the semiconductor device, Figure 1(A) will also be used in subsequent drawings. Similar to the above, some of the components and some of the symbols of the components may be omitted when illustrating.

[0052] The semiconductor device 100 shown in Figures 1(A) and 1(B) includes transistor Tr1 and transistor T It has a transistor Tr2 in which at least a portion of r1 overlaps with each other. Both transistor Tr1 and transistor Tr2 are bottom-gate transistors. .

[0053] The region in which transistors Tr1 and Tr2 overlap at least partially is By incorporating this feature, the area required for transistor placement can be reduced.

[0054] Transistor Tr1 is connected to a conductive film 104 on a substrate 102, and the substrate 102 and conductive film 104 The insulating film 106 above, the oxide semiconductor film 108 on the insulating film 106, and the oxide semiconductor film 108 The conductive film 112a on top, the conductive film 112b on the oxide semiconductor film 108, and the oxide semiconductor film 1 08, insulating film 114 on conductive film 112a and conductive film 112b, and insulating film 114 on insulating film 114 It comprises a film 116 and a conductive film 122c on the insulating film 116.

[0055] Furthermore, transistor Tr2 has a conductive film 112b and an insulating film 114 on the conductive film 112b. , an insulating film 116 on insulating film 114, an oxide semiconductor film 128 on insulating film 116, and an oxide A conductive film 122a on the semiconductor film 128, a conductive film 122b on the oxide semiconductor film 128, and acid An insulating film 124 on a ion semiconductor film 128, a conductive film 122a, and a conductive film 122b, and an insulating film It has an insulating film 126 on 124 and a conductive film 130 on the insulating film 126. 130 is in contact with the conductive film 122a through the openings 182 provided in the insulating films 124 and 126. It will continue.

[0056] As shown in Figures 1(A) and 1(B), the oxide semiconductor film 108 and the oxide semiconductor film 12 Number 8 has overlapping regions. Note that, as shown in Figures 1(A) and 1(B), transistors The channel region formed in the oxide semiconductor film 108 of Tr1 and the oxide of transistor Tr2 It is preferable that the channel regions formed on the monosemiconductor film 128 do not overlap with each other.

[0057] The channel region of transistor Tr1 and the channel region of transistor Tr2 are relative to each other. When they overlap, one transistor operating can affect the other. There is an effect. To avoid this effect, between transistor Tr1 and transistor Tr2 A configuration that increases the spacing, or a conductive film between transistors Tr1 and Tr2. One example is a configuration that includes [a certain feature]. However, in the former configuration, the semiconductor device becomes thicker. Therefore, for example, when forming a semiconductor device 100 on a flexible substrate, flexibility and other properties are important. This can sometimes become a problem. Also, in the case of the latter configuration, the number of steps for forming the conductive film increases, and the former Similar to the previous configuration, the increased thickness of the semiconductor device can sometimes cause problems.

[0058] On the other hand, in a semiconductor device 100 according to one aspect of the present invention, a transistor Tr1 and a transistor The transistor Tr2 is placed on top of each other, and the channel regions of each transistor are provided without overlapping. Furthermore, by overlapping a portion of the oxide semiconductor film in which the channel region is formed, The placement area of ​​the ZISTA can be suitably reduced.

[0059] Furthermore, oxide semiconductor film 108 and oxide semiconductor film 128 are composed of In and M(M) respectively. It has Al, Ga, Y, or Sn, and Zn. For example, oxide semiconductor film 108 In the oxide semiconductor film 128, the atomic ratio of In is greater than the atomic ratio of M. It is preferable to have a region. However, the semiconductor device according to one aspect of the present invention is not limited thereto. A configuration having a region where the atomic ratio of In is less than the atomic ratio of M, or the atomic ratio of In The configuration may have the same region as the atomic ratio of M.

[0060] Furthermore, oxide semiconductor film 108 and oxide semiconductor film 128 have the same composition, or composition It is preferable that they are roughly the same. Composition of oxide semiconductor film 108 and oxide semiconductor film 128 By making them the same, it becomes possible to reduce manufacturing costs. However, this is one aspect of the present invention. The semiconductor device is not limited to this, and includes an oxide semiconductor film 108 and an oxide semiconductor film 128. The composition may be varied.

[0061] In oxide semiconductor film 108 and oxide semiconductor film 128, the atomic ratio of In is greater than the atomic ratio of M. Having a larger region allows for the field effect transfer of transistors Tr1 and Tr2. The degree can be increased. Specifically, transistors Tr1 and Tr2 If the field effect mobility of either one or both is 10 cm 2 / Vs, more preferably exceeding Vs. This refers to the field effect transfer of either or both transistors Tr1 and Tr2. The degree is 30cm 2 It becomes possible to exceed / Vs.

[0062] For example, a transistor with high field-effect mobility, as described above, can be used to signal the gate signal of a display device. By using it in the gate driver that is generated, a display device with a narrow bezel (also called a narrow-bezel display) is provided. It can be used. Furthermore, the above-mentioned transistor with high field-effect mobility can be used in a display device. The source driver that supplies signals from the signal line (especially the source driver has By using it in a demultiplexer connected to the output terminal of a sub-register, it can be connected to a display device. It is possible to provide a display device with a small number of continuous wirings. Also, by using a transistor having a high field-effect mobility as either one or both of the selection transistor and the drive transistor of the pixel circuit of the display device, a display device with high display quality can be provided. For either one or both of the selection transistor and the drive transistor of the pixel circuit of the display device, a transistor having a high field-effect mobility is used to provide a display device with high display quality. It is possible to provide a display device with high display quality. It is possible.

[0063] In addition, the semiconductor device 100 shown in FIGS. 1(A) and 1(B) can be suitably used for the pixel circuit of the display device, and by arranging it as shown in FIGS. 1(A) and 1(B), the pixel density of the display device can be increased. For example, even when the pixel density of the display device exceeds 1000 ppi (pixels per inch), or when the pixel density of the display device exceeds 2000 ppi, by arranging it as shown in FIGS. 1(A) and 1(B), the aperture ratio of the pixel can be increased. Here, ppi is a unit representing the number of pixels per inch. For example, when the pixel density of the display device exceeds 1000 ppi (pixels per inch), or when the pixel density of the display device exceeds 2000 ppi, by arranging it as shown in FIGS. 1(A) and 1(B), the aperture ratio of the pixel can be increased. It is possible to increase the pixel density of the display device. That is, even when the pixel density of the display device exceeds 1000 ppi (pixels per inch), or when the pixel density of the display device exceeds 2000 ppi, by arranging it as shown in FIGS. 1(A) and 1(B), the aperture ratio of the pixel can be increased. Even when the pixel density of the display device exceeds 1000 ppi (pixels per inch), or when the pixel density of the display device exceeds 2000 ppi, by arranging it as shown in FIGS. 1(A) and 1(B), the aperture ratio of the pixel can be increased. ppi is a unit representing the number of pixels per inch.

[0064] <1-2. Pixel Circuit of Display Device> Here, an example of the case where the semiconductor device 100 shown in FIGS. 1(A) and 1(B) is applied to the pixel circuit of the display device will be described using FIG. 2. Using FIG. 2, an example of the case where the semiconductor device 100 shown in FIGS. 1(A) and 1(B) is applied to the pixel circuit of the display device will be described.

[0065] FIG. 2 is a circuit diagram showing an example of the case where the semiconductor device 100 is applied to the pixel circuit of the display device. It is a circuit diagram.

[0066] The semiconductor device 100 shown in FIG. 2 includes a transistor Tr1, a transistor Tr2, a capacitor element Cs1, and a light-emitting element 160. In FIG. 2, a configuration in which two semiconductor devices 100 are adjacent in the column direction is illustrated. The semiconductor device 100 functions as one of the pixels (or also referred to as sub-pixels). Regarding the capacitor element Cs1, it is illustrated in FIG. 1. The semiconductor device 100 shown in FIG. 2 includes a transistor Tr1, a transistor Tr2, a capacitor element Cs1, and a light-emitting element 160. In FIG. 2, a configuration in which two semiconductor devices 100 are adjacent in the column direction is illustrated. The semiconductor device 100 functions as one of the pixels (or also referred to as sub-pixels). The semiconductor device 100 functions as one of the pixels (or also referred to as sub-pixels). For the capacitor element Cs1, it is illustrated in FIG. 1. However, for example, the conductive film 112b on transistor Tr1 and transistor Tr It can be formed using the parasitic capacitance between 2 and the conductive film 122b.

[0067] Furthermore, in the circuit diagram shown in Figure 2, the data line DL is used to write data signals to the pixels. _Y-1, data line DL_Y which writes a data signal to the adjacent pixel, and light-emitting element Anode line ANODE_X-1 that supplies potential to the adjacent light-emitting element, and The anode line ANODE_X and the scan line GL_X that supplies the scan signal to the pixel are shown. Yes, they are.

[0068] One of the source and drain electrodes of transistor Tr1 is connected to the data line DL_Y-1. Electrically connected. Furthermore, the first gate electrode and the second gate of transistor Tr1 The electrodes are electrically connected to the scan line GL_X. Transistor Tr1 is ON or It has a function that controls the writing of data signals by being in an off state.

[0069] One of the pair of electrodes of the capacitive element Cs1 is connected to the source electrode and drain of the transistor Tr1. It is electrically connected to the other electrode. Also, the other electrode of the pair of electrodes of the capacitive element Cs1 is connected to the transistor. It is electrically connected to the second gate electrode (also called the back gate electrode) of the zista Tr2. The capacitive element Cs1 functions as a retention capacitor, holding the data that has been written to it.

[0070] One of the source and drain electrodes of transistor Tr2 is connected to the anode wire ANODE_ It is electrically connected to the X-1.

[0071] One of the pair of electrodes of the light-emitting element 160 is the source electrode and drain electrode of the transistor Tr2. One side is electrically connected to the other electrode, and the other side is electrically connected to the cathode line CATHODE. One of the pair of electrodes of the light-emitting element 160 is electrically connected to the other of the pair of electrodes of the capacitor element Cs1.

[0072] The above configuration is an example of an application of the semiconductor device 100 shown in FIGS. 1(A) and 1(B) to a pixel of a display device.

[0073] <1-3. Configuration of Semiconductor Device> Again, the semiconductor device 100 shown in FIGS. 1(A) and 1(B) will be described. When the semiconductor device 100 shown in FIGS. 1(A) and 1(B) is applied to a pixel of a display device, for example, the channel length (L) and channel width (W) of the transistor, or the line width of the wiring and electrodes connected to the transistor can be made relatively large. For example, compared with the case where the transistor Tr1 and the transistor Tr2 are arranged on the same plane, as shown in FIGS. 1(A) and 1(B), by arranging at least a part of the transistor Tr1 and the transistor Tr2 so as to overlap each other, the line width and the like can be made large, so that the variation in the processing dimensions can be reduced. Also, either one or both of the conductive film and the insulating film can be commonly used for the transistor Trl and the transistor Tr2, so that the number of masks or the number of processes can be reduced. For example, in the transistor Tr1, the conductive film 104 functions as the first gate electrode, the conductive film 112a functions as the source electrode, the conductive film 112b functions as the drain electrode, and the conductive film 122c functions as the second gate electrode. Also, in the transistor Tr1,

[0074]

[0075] ​​​​​​​​​​And insulating film 106 functions as the first gate insulating film, and insulating films 114, 116 are the second It functions as a gate insulating film. Also, in transistor Tr2, the conductive film 112b is One electrode functions as the gate electrode, and the conductive film 122a functions as the source electrode, and the conductive film 122 b functions as the drain electrode, and the conductive film 130 functions as the second gate electrode. In transistor Tr2, insulating films 114 and 116 function as the first gate insulating film. Furthermore, insulating films 124 and 126 function as second gate insulating films.

[0076] In this specification, etc., insulating film 106 is referred to as the first insulating film, and insulating films 114, 116 are referred to as The second insulating film and insulating films 124 and 126 are sometimes referred to as the third insulating film. .

[0077] Furthermore, an insulating film 134 and an insulating film 136 on the insulating film 134 are provided on the conductive film 130. Furthermore, the insulating films 134 and 136 are provided with openings 184 that reach the conductive film 130. Furthermore, a conductive film 138 is provided on the insulating film 136. Note that the conductive film 138 is It is connected to the conductive film 130 through the opening 184.

[0078] Furthermore, an insulating film 140, an EL layer 142, and a conductive film 144 are provided on the conductive film 138. The insulating film 140 covers a portion of the side edge of the conductive film 138, and conducts between adjacent pixels. The film 138 has a function to prevent short circuits. Furthermore, the EL layer 142 has a light-emitting function. Furthermore, the conductive film 138, the EL layer 142, and the conductive film 144 constitute the light-emitting element 160. The conductive film 138 functions as one electrode of the light-emitting element 160, and the conductive film 144 is It functions as the other electrode of the light-emitting element 160.

[0079] As described above, a semiconductor device according to one aspect of the present invention has a stacked structure of multiple transistors, To reduce the footprint of the transistor. Also, in multiple transistors, the insulating film and By using one or both of the conductive films in common, the number of masks or process steps can be reduced. It can be reduced.

[0080] <1-4. Configuration of the gate electrode> Furthermore, as shown in Figures 1(A) and 1(B), transistors Tr1 and Tr2 are Each of these configurations has two gate electrodes.

[0081] Here, the effect of a configuration with two gate electrodes is shown in Figures 1(A)(B) and 3. We will use it to explain.

[0082] Figure 3 corresponds to a cross-sectional view of the section between the dashed-dotted line B1-B2 shown in Figure 1(A). Figure 3 also includes a cross-section of transistor Tr1 in the channel width (W) direction.

[0083] As shown in Figure 3, the conductive film 122c, which functions as the second gate electrode, has an opening 181 It is electrically connected to the conductive film 104 which functions as the first gate electrode via this. Therefore, The same potential is applied to conductive film 104 and conductive film 122c. Also, as shown in Figure 3, The oxide semiconductor film 108 is positioned opposite the conductive film 104 and the conductive film 122c. It is sandwiched between two conductive films that function as gate electrodes: conductive film 104 and conductive film 122. The length of c in the channel width direction is the length of the oxide semiconductor film 108 in the channel width direction. Furthermore, the entire oxide semiconductor film 108 is conductive through the insulating films 106, 114, and 116. It is covered by film 104 and conductive film 122c.

[0084] In other words, conductive film 104 and conductive film 122c are provided on insulating films 106, 114, and 116. It is connected at the opening 181 and is located outside the side edge of the oxide semiconductor film 108. It has a region located in [location].

[0085] By using this configuration, the oxide semiconductor film 108 contained in transistor Tr1 The conductive film 104 and conductive film 122c can electrically surround the area with their respective electric fields. Like Tr1, the channel is formed by the electric fields of the first and second gate electrodes. The transistor device structure electrically surrounds the oxide semiconductor film in which the region is formed. This can be called a rounded channel (S-channel) structure.

[0086] Since transistor Tr1 has an S-channel structure, the first gate electrode is The conductive film 104, which functions in a manner, effectively induces an electric field to create a channel in the oxide semiconductor. Because it can be applied to the membrane 108, the current driving capability of transistor Tr1 is improved. This makes it possible to obtain high on-current characteristics. Furthermore, it is possible to increase the on-current. Therefore, it becomes possible to miniaturize transistor Tr1. Also, transistor Tr1 , conductive film 104 which functions as the first gate electrode and conductive film 104 which functions as the second gate electrode Because it has a structure surrounded by an electrical film 122c, its mechanical strength can be increased.

[0087] In the above explanation, the first gate electrode and the second gate electrode are connected. The configuration is illustrated with an example, but it is not limited to this. For example, the transistor T shown in Figure 1(B) The conductive film 130, which functions as a second gate electrode like r2, is positioned at the base of transistor Tr2. The configuration is such that it is electrically connected to a conductive film 122a that functions as a drain electrode or a drain electrode. That's fine.

[0088] <1-5. Components of a semiconductor device> Next, the components included in the semiconductor device of this embodiment will be described in detail.

[0089] [substrate] There are no major restrictions on the material of the substrate 102, but it should at least be able to withstand subsequent heat treatment. It must have heat resistance. For example, glass substrates, ceramic substrates, quartz substrates, etc. A fire substrate or the like may be used as the substrate 102. Alternatively, silicon or silicon carbide may be used as the material. Single-crystal semiconductor substrates, polycrystalline semiconductor substrates, and compound semiconductors such as silicon germanium are used as materials. It is also possible to apply substrates, SOI substrates, etc., and semiconductor elements are provided on these substrates. The prepared material may be used as the substrate 102. Note that a glass substrate may be used as the substrate 102. If available, 6th generation (1500mm x 1850mm), 7th generation (1870mm x 220 0mm), 8th generation (2200mm x 2400mm), 9th generation (2400mm x 280 By using large-area substrates such as 0mm, 10th generation (2950mm x 3400mm), Large-scale display devices can be manufactured.

[0090] Furthermore, a flexible substrate is used as the substrate 102, and the semiconductor device 100 is directly mounted on the flexible substrate. Alternatively, a release layer may be formed between the substrate 102 and the semiconductor device 100. The delamination layer is separated from the substrate 102 after the semiconductor device is partially or completely completed on it. It can be used to transfer to other substrates. In this case, the semiconductor device 100 is heat resistant It can be mounted on inferior or flexible substrates.

[0091] [Conductive film] Conductive film 104, conductive film 112a, conductive film 112b, conductive film 122a, conductive film 122b, The conductive films 122c, 130, 138, and 144 are chromium (C r), copper (Cu), aluminum (Al), gold (Au), silver (Ag), zinc (Zn), mo Ribdenum (Mo), Tantalum (Ta), Titanium (Ti), Tungsten (W), Manganese Metal elements selected from (Mn), nickel (Ni), iron (Fe), and cobalt (Co), Alternatively, an alloy containing the aforementioned metal elements, or an alloy combining the aforementioned metal elements, etc. They can be formed in different ways.

[0092] Also, conductive film 104, conductive film 112a, conductive film 112b, conductive film 122a, conductive film 12 2b, conductive film 122c, conductive film 130, conductive film 138, and conductive film 144 contain indiu Oxides containing tungsten and tin, oxides containing tungsten and indium, tungsten and Oxides containing indium and zinc, oxides containing titanium and indium, titanium and Oxides containing indium and tin, oxides containing indium and zinc, silicon and indium Oxide derivatives such as oxides containing um and tin, and oxides containing indium, gallium, and zinc. It is also possible to apply electromechanisms.

[0093] In particular, the above-mentioned oxide conductor can be suitably used for the conductive film 130. Here, This section will explain oxide conductors. In this specification and elsewhere, oxide conductors are referred to as OC (Oxid It may also be called an e Conductor. Examples of oxide conductors include oxide hemp When an oxygen vacancy is formed in a conductor and hydrogen is added to the oxygen vacancy, a donor level is formed near the conduction band. This process is carried out. As a result, the oxide semiconductor becomes highly conductive and turns into a conductor. Oxide semiconductors can be called oxide conductors. Generally, oxide semiconductors are energy - Due to its large gap, it is transparent to visible light. On the other hand, oxide conductors are conductive It is an oxide semiconductor having a donor level near the band. Therefore, oxide conductors are donors The effect of absorption due to energy levels is small, and it has light transmittance to visible light comparable to oxide semiconductors. .

[0094] Also, conductive film 104, conductive film 112a, conductive film 112b, conductive film 122a, conductive film 12 2b, conductive film 122c, conductive film 130, conductive film 138, and conductive film 144 contain Cu-X Even if an alloy film (X is Mn, Ni, Cr, Fe, Co, Mo, Ta, or Ti) is applied... Good. By using a Cu-X alloy film, it can be processed using a wet etching process. This makes it possible to reduce manufacturing costs.

[0095] In particular, conductive film 104, conductive film 112a, conductive film 112b, conductive film 122a, conductive film 12 The Cu-X alloy film described above is preferred for one or more of 2b and conductive films 122c. It can be used for this purpose. As the Cu-X alloy film, a Cu-Mn alloy film is particularly preferred.

[0096] Also, conductive film 104, conductive film 112a, conductive film 112b, conductive film 122a, conductive film 12 2b and one or more of the conductive films 122c contain, among the above-mentioned metal elements, particularly Selected from aluminum, copper, titanium, tungsten, tantalum, and molybdenum It is preferable to have one or more of these.

[0097] Also, conductive film 104, conductive film 112a, conductive film 112b, conductive film 122a, conductive film 12 One or more of 2b and conductive films 122c contain nitrogen and tantalum, so It is preferable to use a tantalum nitride film. This tantalum nitride film is conductive and contains copper Alternatively, it has high barrier properties against hydrogen. Furthermore, the tantalum nitride film also has a high barrier property against hydrogen. Because the release of hydrogen is small, the metal film in contact with the oxide semiconductor film 108, or the oxide semiconductor It can be most preferably used as a metal film in the vicinity of film 108.

[0098] [Insulated film] Insulating film 106, insulating film 114, insulating film 116, insulating film 124, insulating film 126, insulating film 1 34. The insulating film 136 and insulating film 140 are a silicon oxide film and a silicon oxide nitride film. silicon nitride film, silicon nitride film, aluminum oxide film, hafnium oxide film, oxide Yttrium film, zirconium oxide film, gallium oxide film, tantalum oxide film, magnesium oxide film An insulating layer containing one or more of the following: a luminum film, a lanthanum oxide film, a cerium oxide film, and a neodymium oxide film. Each can be used.

[0099] Furthermore, the insulating film 106 functions as a blocking film that suppresses oxygen permeation. For example, insulating film 114, insulating film 116, oxide semiconductor film 108, oxide semiconductor film 128, When one or more of the insulating film 124 and insulating film 126 have an excess oxygen region In this configuration, the insulating film 106 can suppress the permeation of oxygen.

[0100] Furthermore, contact with either or both of the oxide semiconductor film 108 and the oxide semiconductor film 128. The insulating film is preferably an oxide insulating film, and is applied in excess of the stoichiometric composition. It is more preferable to have a region containing oxygen (excess oxygen region). In other words, excess oxygen Oxide insulating films having elementary regions are insulating films that can release oxygen.

[0101] Furthermore, as an oxide insulating film having the above-mentioned excess oxygen region, for example, under an oxygen atmosphere Forming an insulating film, heat-treating the insulating film after deposition in an oxygen atmosphere, or insulating film after deposition The film can be formed by adding oxygen to the film. Another method involves adding oxygen to the insulating film after it has been formed. Plasma treatment is preferred for this purpose.

[0102] Furthermore, it functions as an insulating film for the gates of transistors Tr1 and Tr2. Hafnium oxide may be used for the film. When using nium, the following effects are produced.

[0103] Hafnium oxide has a higher dielectric constant compared to silicon oxide and silicon oxide nitride. Therefore, compared to the case using silicon oxide, the thickness of the insulating film can be increased, thus tunnel This can reduce leakage current caused by current. In other words, a transistor with a small off-current It is possible to achieve this. Furthermore, hafnium oxide having a crystalline structure has an amorphous structure It has a higher dielectric constant compared to hafnium oxide, which has a low off-current. For use as a transistor, it is preferable to use hafnium oxide having a crystalline structure. Examples of crystal structures include monoclinic and cubic systems. However, one aspect of the present invention is... The term "sama" is not limited to these examples.

[0104] Furthermore, it functions as an insulating film for the gates of transistors Tr1 and Tr2. Silicon nitride may be used for the film. When using silicon nitride, the following effects are achieved. Compared to silicon oxide, silicon nitride has a higher dielectric constant. The efficiency is high, and the thickness required to obtain capacitance equivalent to silicon oxide is large, therefore the insulating film is Thick film formation is possible. Therefore, the dielectric strength of transistors Tr1 and Tr2 By suppressing the pressure drop and further improving the dielectric strength, transistor Tr1 and transistor This can suppress electrostatic discharge breakdown of Tr2.

[0105] Furthermore, insulating films 114, 116, 124, and 126 are oxide semiconductor films 108 or oxide It has the function of supplying oxygen to one or both of the semiconductor films 128. The edge films 114, 116, 124, and 126 contain oxygen. Also, the insulating films 114 and 124 are It is an insulating film that can permeate oxygen. The insulating film 114 is an insulating film that will be formed later. It also functions as a damage mitigation film for the oxide semiconductor film 108 when forming film 116, and The edge film 124 is a barrier to the oxide semiconductor film 128 when forming the insulating film 126 which will be formed later. It also functions as an image relaxation membrane.

[0106] The insulating films 114 and 124 have a thickness of 5 nm to 150 nm, preferably 5 nm. Silicon oxide, silicon oxide, silicon nitride, etc., with a wavelength of 50 nm or less can be used.

[0107] Furthermore, the insulating films 114 and 124 preferably have a low defect rate, and typically, ESR Measurement revealed that the signal appearing at g=2.001 originates from the silicon dangling bond. Pin density is 3 × 10 17 spins / cm 3 The following is preferable. This is an insulating film. If the defect density in 114 and 124 is high, oxygen will bond to the defects, and the insulating film 11 The amount of oxygen permeable at point 4 decreases.

[0108] Furthermore, insulating films 114 and 124 have low energy level density due to nitrogen oxides. It can be formed using this. Furthermore, the level density due to the nitrogen oxide is the oxide semiconductor. The energy at the upper end of the valence band of a body membrane (Ev_os) and the energy at the lower end of the conduction band of an oxide semiconductor film It may be formed between the energy (Ec_os). As the oxide insulating film, nitrogen Silicon oxide nitride film with low oxide emission, or silicon oxide nitride film with low nitrogen oxide emission. Aluminum oxide films and the like can be used.

[0109] Furthermore, silicon oxidnitride films with low nitrogen oxide emissions can be analyzed using the temperature-controlled desorption gas analysis method (TD). In S), the membrane releases more ammonia than nitrogen oxides, and typically, Ammonia release amount is 1 × 10 18 cm -3 The above 5 x 10 19 cm -3 The following applies. The amount of ammonia released above is when the heat treatment temperature in TDS is between 50°C and 650°C. The total amount is below, or in the range of 50°C to 550°C. Also, the above ammonia emissions The output is the total amount converted to ammonia molecules in TDS.

[0110] Nitrogen oxides (NO x (where x is greater than 0 and less than or equal to 2, preferably between 1 and 2), typically NO2 or NO forms energy levels in insulating films 114, 124, etc. These energy levels are oxides. It is located within the energy gap of semiconductor films 108 and 128. Therefore, nitrogen oxides are located within the energy gap. The interface between insulating film 114 and oxide semiconductor film 108, or insulating film 124 and oxide semiconductor film When diffusing into the interface 128, the energy level traps electrons on the insulating film 114, 124 side. This can occur. As a result, trapped electrons can be trapped between the insulating film 114 and the oxide semiconductor film 1 Because it remains near the interface of 08, or near the interface of the insulating film 124 and the oxide semiconductor film 128. This shifts the transistor's threshold voltage in the positive direction.

[0111] Furthermore, nitrogen oxides react with ammonia and oxygen during heat treatment. Insulating film 114 The nitrogen oxides contained in 124 are, in the heat treatment, contained in the insulating films 116 and 126. Because it reacts with ammonia, nitrogen oxides contained in insulating films 114 and 124 are reduced. Therefore, at the interface between the insulating film 114 and the oxide semiconductor film 108, or between the insulating film 124 and the oxide At the interface of the monosemiconductor film 128, electrons are less likely to be trapped.

[0112] By using the above oxide insulating film as insulating films 114 and 124, the transistor structure It is possible to reduce the shift in the value voltage, thereby reducing fluctuations in the electrical characteristics of the transistor. It is possible.

[0113] Furthermore, the heat treatment in the transistor manufacturing process typically involves heating to temperatures between 300°C and 350°C. After heat treatment, the insulating films 114 and 124 were measured at an ESR of 100K or less, and the spectral properties obtained were obtained. In the cult, the first signal is when the g value is between 2.037 and 2.039, and the g value is 2.00 A second signal between 1 and 2.003, and a second signal with a g value between 1.964 and 1.966. Three signals are observed. Note that the split width between the first and second signals is Furthermore, the split width of the second and third signals is used in the X-band ESR measurement. It is approximately 5mT. Also, the first signal is g with a g value between 2.037 and 2.039. A second signal with a value between 2.001 and 2.003, and a g value between 1.964 and 1.9 The sum of the spin densities of the third signal, which is 66 or less, is 1 × 10⁻⁶. 18 spins / cm 3 It is less than 1 × 10⁻⁶. 17 spins / cm 3 The above 1 x 10 18 spins / cm 3 It is less than.

[0114] Furthermore, in ESR spectra below 100K, the g value is between 2.037 and 2.039. Below are the first signal, the second signal with a g value between 2.001 and 2.003, and the g value The sum of the spin densities of the third signal, where is between 1.964 and 1.966, is nitrogen acid Monster (NO x (where x is greater than 0 and less than or equal to 2, preferably between 1 and 2) the signal caused This corresponds to the sum of the pin densities. Typical examples of nitrogen oxides include nitric oxide and nitrogen dioxide. There is a first signal with a g value of 2.037 or higher and 2.039 or lower, and a g value of 2.00 A second signal between 1 and 2.003, and a g value between 1.964 and 1.966. The smaller the sum of the spin densities of the third signal, the less nitrogen oxides contained in the oxide insulating film. It can be said that the amount of the substance is low.

[0115] Furthermore, the above oxide insulating film has a nitrogen concentration of 6 × 10 as measured by SIMS. 20 atoms / cm 3 The following applies:

[0116] The substrate temperature is between 220°C and 350°C, and PEC is performed using silane and nitrous oxide. By forming the above oxide insulating film using the VD method, a dense and hard film is obtained. It can be formed.

[0117] The insulating films 116 and 126 are oxides containing more oxygen than satisfactorily satisfying the stoichiometric composition. Formed using an insulating film. An oxide insulating film containing more oxygen than satisfactorily satisfying the stoichiometric composition. The edge film releases some of its oxygen upon heating. More acid than oxygen to satisfy the stoichiometric composition. The oxide insulating film containing element releases an amount of oxygen of 1.0 × 10⁻¹⁰ 19 cm -3 The above, preferably 3 .0 × 10 20 cm -3 That concludes the explanation. Note that the amount of oxygen released above is measured by heating in TDS. For a total amount processed at a temperature of 50°C to 650°C, or within the range of 50°C to 550°C. Yes. Furthermore, the oxygen release amount mentioned above is the total amount converted to oxygen molecules in TDS.

[0118] The insulating films 116 and 126 have a thickness of 30 nm to 500 nm, preferably 50 Silicon oxide, silicon oxide, silicon nitride, etc., with a wavelength of 400 nm or more can be used.

[0119] Furthermore, it is preferable that the insulating films 116 and 126 have a low defect rate, and typically, ESR Measurement revealed that the signal appearing at g=2.001 originates from the silicon dangling bond. Pin density is 1.5 × 10 18 spins / cm 3Less than, and even 1 × 10 18 spins / cm 3 The following is preferable:

[0120] Furthermore, insulating film 114 and insulating film 116, and insulating film 124 and insulating film 126 are made of the same type of material. Since an insulating film can be used, the interface between insulating film 114 and insulating film 116, and the insulating film In some cases, the interface between 124 and the insulating film 126 cannot be clearly identified. Therefore, in this implementation In its form, the interface between insulating film 114 and insulating film 116, and insulating film 124 and insulating film 12 The interface with 6 is shown by a dashed line.

[0121] The insulating film 134 serves as a protective insulating film for transistors Tr1 and Tr2. To have the ability.

[0122] The insulating film 134 has either hydrogen or nitrogen, or both. 34 contains nitrogen and silicon. The insulating film 134 contains oxygen, hydrogen, water, and alkali. It has the function of blocking metals, alkaline earth metals, etc. By providing an insulating film 134 Therefore, the diffusion of oxygen from the oxide semiconductor film 108 and the oxide semiconductor film 128 to the outside, and Diffusion of oxygen contained in the border films 114, 116, 124, and 126 to the outside, and oxidation from the outside This prevents hydrogen, water, and other substances from entering the semiconductor films 108 and 128.

[0123] For example, a nitride insulating film can be used as the insulating film 134. Examples include silicon nitride, silicon oxide nitride, aluminum nitride, and aluminum oxide nitride. These include:

[0124] [Oxide semiconductor film] The oxide semiconductor film 108 and the oxide semiconductor film 128 are made from the materials described above, respectively. It is possible to be there.

[0125] When oxide semiconductor film 108 and oxide semiconductor film 128 are In-M-Zn oxide, - Number of atoms of metal elements in the sputtering target used to deposit M-Zn oxide films The ratio preferably satisfies In > M. As for the ratio of the number of atoms of the basic elements, In:M:Zn = 2:1:3, In:M:Zn = 3:1:2, In Examples include :M:Zn=4:2:4.1.

[0126] Furthermore, in the case where oxide semiconductor film 108 and oxide semiconductor film 128 are In-M-Zn oxide... The metal elements of the sputtering target used to deposit In-M-Zn oxide films The atomic ratio may be a composition that satisfies In ≤ M. Gold in such a sputtering target The atomic ratio of the group elements is In:M:Zn = 1:1:1, and In:M:Zn = 1:1:1. 2, In:M:Zn=1:3:2, In:M:Zn=1:3:4, In:M:Zn=1: Examples include 3:6, etc.

[0127] Furthermore, oxide semiconductor film 108 and oxide semiconductor film 128 are each In-M-Zn acid In the case of nitriles, the sputtering target includes polycrystalline In-M-Zn oxide. Using a target is preferable. A target containing polycrystalline In-M-Zn oxide is used. This makes it easier to form crystalline oxide semiconductor films 108 and 128. The atomic ratio of the oxide semiconductor film 108 and oxide semiconductor film 128 to be formed is Each of these is the plus or minus atomic ratio of the metal elements contained in the sputtering target mentioned above. Includes a 40% variation in the oxide semiconductor film 108 and oxide semiconductor film 128. For the puttering target, an atomic ratio of In:Ga:Zn = 4:2:4.1 is used. In this case, the atomic ratio of the oxide semiconductor film 108 and oxide semiconductor film 128 to be deposited is: There are cases where Ga:Zn = 4:2:3 in the vicinity.

[0128] Furthermore, the oxide semiconductor film 108 and the oxide semiconductor film 128 have an energy gap of 2e It is V or higher, preferably 2.5eV or higher, more preferably 3eV or higher. By using an oxide semiconductor with a wide energy gap, transistor Tr1 and Trans This can reduce the off-current of Tr2.

[0129] Furthermore, the thickness of oxide semiconductor film 108 and oxide semiconductor film 128 is 3 nm or more. 200nm or less, preferably 3nm to 100nm, more preferably 3nm to 5nm The nm size should be 0 nm or less.

[0130] Furthermore, the hydrogen contained in oxide semiconductor film 108 and oxide semiconductor film 128 is a metal atom and It reacts with the oxygen it binds to to form water, and at the same time, the lattice (or the part from which oxygen has been removed) from which oxygen has been removed An oxygen vacancy is formed (in minutes). When hydrogen enters this oxygen vacancy, electrons, which act as carriers, are generated. In some cases, this can occur. Also, some of the hydrogen combines with oxygen that is bonded to a metal atom, and in the carrier It can generate certain electrons. Therefore, using an oxide semiconductor film containing hydrogen... Lampistors tend to exhibit normally-on characteristics. Therefore, oxide semiconductor film 108 and acid Preferably, the hydrogen content in the ionized semiconductor film 128 is reduced as much as possible.

[0131] Specifically, SIMS analysis was performed on oxide semiconductor film 108 and oxide semiconductor film 128. The hydrogen concentrations obtained by each method are 2 × 10 20 atoms / cm 3 The following, preferably 5 x 10 19 atoms / cm 3 More preferably 1 × 10 19 atoms / cm 3 Below, 5 x 10 18 atoms / cm 3 The following is preferably 1 × 10 18 atoms / cm 3 The following is more preferable: 5 x 10 17 atoms / cm 3 More preferably, 1 × 1 0 16 atoms / cm 3 The following applies:

[0132] Furthermore, in oxide semiconductor film 108 and oxide semiconductor film 128, one of the Group 14 elements When silicon or carbon is included, oxide semiconductor film 108 and oxide semiconductor film 12 At 8, the oxygen vacancy increases, and it becomes n-type. Therefore, the oxide semiconductor film 108 and The silicon concentration obtained by SIMS analysis in oxide semiconductor film 128 is given by 2 ×10 18 atoms / cm 3 The following is preferably 2 × 10 17 atoms / cm 3 The following and do. Furthermore, SIMS analysis of oxide semiconductor film 108 and oxide semiconductor film 128 was obtained. The carbon concentrations are 2 × 10 18 atoms / cm 3 The following is preferably 2 × 10 1 7 atoms / cm 3 The following applies:

[0133] Furthermore, SIMS analysis was performed on oxide semiconductor film 108 and oxide semiconductor film 128. The resulting alkali metal or alkaline earth metal concentrations are 1 × 10⁻⁶ each. 18 Atom s / cm 3 The following is preferably 2 × 10 16 atoms / cm 3 The following applies: Alkali metals And alkaline earth metals may generate carriers when they combine with oxide semiconductors. The off-current of the transistor may increase. Therefore, the oxide semiconductor film 108 and Furthermore, reducing the concentration of alkali metals or alkaline earth metals in the oxide semiconductor film 128 is possible. preferable.

[0134] Furthermore, the oxide semiconductor film 108 and the oxide semiconductor film 128 can also be in a non-single crystal structure. Good. Non-single crystal structures include, for example, CAAC-OS (C Axis Aligne), which will be discussed later. d Crystalline Oxide Semiconductor), polycrystalline structure This includes microcrystalline or amorphous structures. In non-single-crystal structures, amorphous structures are the most defective. CAAC-OS has a high level density, while CAAC-OS has the lowest defect level density.

[0135] Furthermore, the various films mentioned above, such as conductive films, insulating films, and oxide semiconductor films, include spa Taring method, Plasma Chemical Vapor Deposition (PECVD) Chemical Vapor Deposition) method, thermal CVD (Chemical It can be formed by the (al Vapor Deposition) method. As a VD method, MOCVD (Metal Organic Chemical Vapor (r Deposition) method, or ALD (Atomic Layer Deposition) method. Examples include the tion method.

[0136] Thermal CVD is a film deposition method that does not use plasma, so defects can occur due to plasma damage. It has the advantage of never being accomplished.

[0137] In the thermal CVD method, the raw material gas and oxidizer are simultaneously introduced into the chamber, and the chamber is then cooled to the atmosphere. The film is formed by reacting the substrate near or on the substrate under pressure or reduced pressure, causing the film to deposit on the substrate. You may do so.

[0138] Furthermore, the ALD method maintains atmospheric pressure or reduced pressure inside the chamber and uses raw material gases for the reaction. It may be used to perform film formation.

[0139] Thermal CVD methods such as MOCVD and ALD are used for the conductive films, insulating films, and oxides of the above embodiments. It can form various films, such as semiconductor films, for example, an In-Ga-ZnO film. In such cases, trimethylindium, trimethylgallium, and dimethylzinc are used. The chemical formula for trimethylindium is In(CH3)3. The chemical formula for lium is Ga(CH3)3. The chemical formula for dimethylzinc is Zn(C It is H3)2. Furthermore, it is not limited to these combinations, and trimethylgallium can be substituted with Triethylgallium (chemical formula Ga(C2H5)3) can also be used, along with dimethylzinc. Alternatively, diethylzinc (chemical formula Zn(C2H5)2) can be used.

[0140] For example, when forming a hafnium oxide film using a film deposition apparatus that utilizes ALD, the solvent and a liquid containing hafnium precursor compounds (such as hafnium alkoxide or tetrakisdimethyl A raw material gas obtained by vaporizing hafnium amides (such as amide hafnium (TDMAH)) and an acid Two types of gases, ozone (O3), are used as nitrifying agents. Note that tetrakisdimethylamide is also used. The chemical formula for humium is Hf[N(CH3)2]4. Other material liquids include tetrahedron. Examples include lacs(ethylmethylamide)hafnium.

[0141] For example, when forming an aluminum oxide film using a film deposition apparatus that utilizes ALD, A liquid containing a medium and an aluminum precursor compound (such as trimethylaluminum (TMA)) Two types of gases are used: a vaporized raw material gas and H2O as an oxidizing agent. The chemical formula for aluminum is Al(CH3)3. Other material solutions include Tris( Dimethylamide) Aluminum, Triisobutylaluminum, Aluminum Tris(2 Examples include 2,6,6-tetramethyl-3,5-heptanedione).

[0142] For example, when forming a silicon oxide film using a film deposition apparatus that utilizes ALD, hexa Chlorodisilane is adsorbed onto the film-forming surface, and chlorine contained in the adsorbed material is removed, resulting in an oxidizing gas (O 2. A radical of nitrous oxide is supplied and reacted with the adsorbed material.

[0143] For example, when depositing a tungsten film using a film deposition apparatus that utilizes ALD, WF6 An initial tungsten film is formed using gas and B2H6 gas, and then WF6 gas and H2 A tungsten film is formed using gas. Note that SiH4 gas is used instead of B2H6 gas. You may use it.

[0144] For example, oxide semiconductor films, such as In-Ga-ZnO, can be deposited using an ALD (Advanced Laser Deposition) system. When forming a film, an In-O layer is formed using In(CH3)3 gas and O3 gas. Then, a GaO layer is formed using Ga(CH3)3 gas and O3 gas, and then Z A ZnO layer is formed using n(CH3)2 gas and O3 gas. Note the order of these layers. This is not the only example. Furthermore, by mixing these gases, In-Ga-O layers and In-Zn-O layers can be formed. Alternatively, a mixed compound layer such as a Ga-Zn-O layer may be formed. Note that Ar may be used instead of O3 gas. H2O gas obtained by bubbling with an inert gas such as can also be used, but O without H It is preferable to use gas 3. Also, instead of In(CH3)3 gas, In(C2H5) You may also use three gases. Alternatively, you can use Ga(C2H5)3 gas instead of Ga(CH3)3 gas. Alternatively, Zn(CH3)2 gas may be used.

[0145] <1-6. Semiconductor device configuration example 2> Next, a modified example of the semiconductor device 100 shown in Figures 1(A) and 1(B) is shown in Figures 4(A) and 4(B). This will be explained using Figure 5.

[0146] Figure 4(A) is a cross-sectional view of a modified example of the semiconductor device 100 shown in Figure 1(B), and Figure 4(B) Figure 5 is a cross-sectional view of a modified example of the semiconductor device 100 shown in Figure 1(B), and Figure 5 is a cross-sectional view of Figure 1(B). This is a cross-sectional view of a modified example of the semiconductor device 100 shown.

[0147] Figure 4(A) shows the second gate electrode of transistor Tr1 in semiconductor device 100. This configuration does not include a conductive film 122c that functions in this way.

[0148] Figure 4(B) shows the second gate electrode of transistor Tr2 in semiconductor device 100. This configuration includes a conductive film 130 that functions as a conductive film, and an insulating film 134 on the conductive film 130 is not provided. Furthermore, in Figure 4(B), the opening 182 provided in the insulating film 124 and insulating film 126, and Instead of the opening 184 provided in the edge film 134 and insulating film 136, insulating film 124, The edge film 126 and the insulating film 136 are configured to have openings 183. Having only one opening reduces the number of manufacturing steps, making it preferable.

[0149] Figure 5 shows the second gate electrode of transistor Tr1 in semiconductor device 100. The conductive film 122c and the conductive film 1 that functions as the second gate electrode of the transistor Tr2 30 and the insulating film 134 on the conductive film 130 are not provided in this configuration. Also, Figure 4(B) and Similarly, the insulating film 124, insulating film 126, and insulating film 136 are provided with openings 183. It is complete.

[0150] <1-7. Semiconductor device configuration example 3> Next, a modified example of the semiconductor device 100 shown in Figures 1(A) and 1(B) is shown in Figures 6(A) and 6(B). This will be explained using Figure 7.

[0151] This section describes the stacked structure of oxide semiconductor films.

[0152] Figures 6(A) and (B) show the channel length (L) of transistor Tr1 in semiconductor device 100. This is a cross-sectional view in the direction of ).

[0153] Figure 6(A) shows the oxide semiconductor film 108 of transistor Tr1, and the oxide semiconductor film 108a, oxide semiconductor film 108b on oxide semiconductor film 108a, and oxide semiconductor film 1 The configuration has an oxide semiconductor film 108c on 08b. That is, the oxide semiconductor film is It has a three-layer laminated structure.

[0154] Figure 6(B) shows the oxide semiconductor film 108 of transistor Tr1, and the oxide semiconductor film The configuration includes 108b and an oxide semiconductor film 108c on the oxide semiconductor film 108b. In other words, it has a stacked structure of two oxide semiconductor films.

[0155] An example of the band structure of the oxide semiconductor film 108 and the insulating film in contact with the oxide semiconductor film 108 is shown below. This is shown in Figures 7(A) and 7(B).

[0156] Figure 7(A) shows insulating film 106, oxide semiconductor films 108a, 108b, 108c, and an insulating film. This is an example of a band structure in the film thickness direction of a laminated structure having a border film 114. Also, Figure 7(B) A laminated structure having insulating film 106, oxide semiconductor films 108b, 108c, and insulating film 114 This is an example of the band structure in the film thickness direction. Note that the band structure is shown in an anechoic manner for ease of understanding. Conduction band of the edge film 106, oxide semiconductor films 108a, 108b, 108c, and insulating film 114 This shows the lower energy level (Ec).

[0157] Furthermore, Figure 7(A) shows a silicon oxide film used as insulating film 106 and insulating film 114. For the oxide semiconductor film 108a, the atomic ratio of metal elements is In:Ga:Zn = 1:3:2, which is gold. Using an oxide semiconductor film formed with a group oxide target, oxide semiconductor film 108b The atomic ratio of the metal elements is In:Ga:Zn = 4:2:4.1 for the metal oxide target. Using an oxide semiconductor film formed using the above method, the original metal element is used as the oxide semiconductor film 108c. The oxidation formed using a metal oxide target with a particle ratio of In:Ga:Zn=1:3:2 This is a band diagram of a configuration using a monocrystalline semiconductor film.

[0158] Furthermore, Figure 7(B) shows a silicon oxide film used as insulating film 106 and insulating film 114. For the oxide semiconductor film 10⁸b, the atomic ratio of the metal elements is In:Ga:Zn = 4:2:4.1 Using an oxide semiconductor film formed with a metal oxide target, the oxide semiconductor film 10 As 8c, the atomic ratio of metal elements is In:Ga:Zn = 1:3:2 for a metal oxide target. This is a band diagram of a configuration using a metal oxide film formed using [a specific method / tool].

[0159] As shown in Figures 7(A) and 7(B), the oxide semiconductor films 108a, 108b, and 108c Therefore, the energy levels at the lower end of the conduction band change smoothly. In other words, they change continuously. This can also be described as a continuous junction. In order to have such a band structure, oxides The interface between the semiconductor film 108a and the oxide semiconductor film 108b, or the interface between the oxide semiconductor film 108b and At the interface with the oxide semiconductor film 108c, defect levels such as trap centers and recombination centers Assume that no impurities that would form such a compound are present.

[0160] To form a continuous junction in oxide semiconductor films 108a, 108b, and 108c, load Each film is deposited using a multi-chamber type film deposition apparatus (sputtering apparatus) equipped with a locking chamber. It is necessary to continuously stack the materials without exposing them to the atmosphere.

[0161] By using the configuration shown in Figures 7(A) and 7(B), the oxide semiconductor film 108b forms a well. In a transistor using the above stacked structure, the channel region is an oxide semiconductor film 10 It can be seen that it is formed in 8b.

[0162] Furthermore, by providing oxide semiconductor films 108a and 108c, the trap levels are set to oxide It can be kept away from the semiconductor film 108b.

[0163] Furthermore, the trap level functions as a channel region in the conduction band of oxide semiconductor film 108b. The energy levels at the edges (Ec) can be farther from the vacuum level, and electrons can enter the trap levels. This makes it easier for electrons to accumulate. The accumulation of electrons in the trap level causes negative fixed This results in an electric charge, and the transistor's threshold voltage shifts to the positive direction. Therefore, , the trap level is more true than the energy level (Ec) of the lower end of the conduction band of the oxide semiconductor film 108b. It is preferable to configure it so that it approaches the empty level. By doing so, the trap level This makes it more difficult for electrons to accumulate, and it is possible to increase the on-current of the transistor. This can increase the field effect mobility.

[0164] Furthermore, oxide semiconductor films 108a and 108c are below the conduction band than oxide semiconductor film 108b. The edge energy levels are close to the vacuum level, typically in the conduction band of oxide semiconductor film 108b. The energy levels at the edge and the energy levels at the lower edge of the conduction band of the oxide semiconductor films 108a and 108c. The difference from the position is 0.15 eV or more, or 0.5 eV or more and 2 eV or less, or 1 eV The following applies: that is, the electron affinity of the oxide semiconductor films 108a and 108c, and the oxide semiconductor The difference with the electron affinity of the body membrane 108b is 0.15 eV or greater, or 0.5 eV or greater, and 2 It is less than or equal to eV, or less than 1 eV.

[0165] With this configuration, the oxide semiconductor film 108b becomes the main path for the current, It functions as a channel region. In addition, the oxide semiconductor films 108a and 108c are channel regions. The oxide semiconductor film 108b formed is composed of one or more metal elements. Since it is a semiconductor film, the interface between the oxide semiconductor film 108a and the oxide semiconductor film 108b, Alternatively, at the interface between the oxide semiconductor film 108b and the oxide semiconductor film 108c, interfacial scattering occurs. It is less likely to become stiff. Therefore, the movement of carriers is not hindered at the interface, so the transient The field effect mobility of the element increases.

[0166] Furthermore, the oxide semiconductor films 108a and 108c function as part of the channel region. To prevent this, a material with sufficiently low conductivity shall be used. Alternatively, an oxide semiconductor film 10⁸a and 10⁸c have electron affinity (the difference between the vacuum level and the energy level at the bottom of the conduction band). The energy level at the lower end of the conduction band is smaller than that of the oxide semiconductor film 108b. A material with a difference (band offset) from the lower energy level of the conduction band 10⁸b is used. This will be done to suppress the occurrence of threshold voltage differences that depend on the magnitude of the drain voltage. In order to control this, the energy levels at the lower end of the conduction band of the oxide semiconductor films 108a and 108c must be Using a material whose energy level is closer to the vacuum level than the energy level at the lower end of the conduction band of the oxide semiconductor film 108b This is preferable. For example, the energy level at the lower end of the conduction band of the oxide semiconductor film 108b and the acid The difference between the energy levels of the lower end of the conduction band of the ionized semiconductor films 108a and 108c is less than 0.2 eV. Preferably, the voltage is 0.5 eV or higher.

[0167] Furthermore, the oxide semiconductor films 108a and 108c do not contain a spinel-type crystal structure within the film. It is preferable that the oxide semiconductor films 108a and 108c contain a spinel-type crystal structure. If included, at the interface between the spinel-type crystal structure and other regions, conductive films 112a, 11 In some cases, the constituent elements of 2b may diffuse into the oxide semiconductor film 108b. If the conductive films 108a and 108c are CAAC-OS as described later, then conductive films 112a and 11 The blocking properties of the constituent elements of 2b, such as copper, become higher, which is preferable.

[0168] The thickness of the oxide semiconductor films 108a and 108c depends on the constituent elements of the conductive films 112a and 112b. A film thickness greater than or equal to that which can suppress diffusion into the oxide semiconductor film 108b, and which provides insulation. The film thickness is set to a level that suppresses the supply of oxygen from film 114 to oxide semiconductor film 108b. For example, If the thickness of the oxide semiconductor films 108a and 108c is 10 nm or more, the conductive film 112a, This can suppress the diffusion of constituent elements of 112b into the oxide semiconductor film 108b. Furthermore, if the thickness of the oxide semiconductor films 108a and 108c is 100 nm or less, the insulating film 114 This allows for an effective supply of oxygen to the oxide semiconductor film 108b.

[0169] Oxide semiconductor films 108a and 108c are In-M-Zn oxide (where M is Al, Ga, Y, ma When (or Sn), by having M in a higher atomic ratio than In, the oxide semiconductor film 10 The energy gap between 8a and 108c can be increased, and the electron affinity can be decreased. Therefore, acid The difference in electron affinity with the ionized semiconductor film 108b can be controlled by the composition of M. In some cases, M is a metallic element with a strong bonding force with oxygen, so these elements are I Having a higher atomic ratio than n makes oxygen deficiency less likely to occur.

[0170] Furthermore, when the oxide semiconductor films 108a and 108c are In-M-Zn oxides, Zn The atomic ratio of In and M, excluding O, is preferably 50 atomic% In. Less than, M is higher than 50 atomic%, and more preferably In is 25 atomic% Less than 75, M is greater than 75 atomic%. Also, oxide semiconductor films 108a and 108c A gallium oxide film may be used instead.

[0171] Furthermore, in the case where the oxide semiconductor films 108a, 108b, and 108c are In-M-Zn oxide... Compared to oxide semiconductor film 108b, the M contained in oxide semiconductor films 108a and 108c The atomic ratio is large, and typically compared to the atoms contained in oxide semiconductor film 108b, The atomic ratio is 1.5 times or more, preferably 2 times or more, and more preferably 3 times or more higher. .

[0172] Furthermore, in the case where the oxide semiconductor films 108a, 108b, and 108c are In-M-Zn oxide... The oxide semiconductor film 108b is constructed with In:M:Zn=x1:y1:z1 [atomic ratio], and the oxide semiconductor film is constructed with In:M:Zn=x1:y1:z1. If the conductive films 108a and 108c are in In:M:Zn=x2:y2:z2 [atomic ratio], y2 / x2 is greater than y1 / x1, preferably y2 / x2 is 1. It is 5 times or more. More preferably, y2 / x2 is 2 times or more greater than y1 / x1, and Preferably, y2 / x2 is 3 times or more, or 4 times or more, greater than y1 / x1. In the oxide semiconductor film 108b, if y1 is greater than or equal to x1, the oxide semiconductor film 108b This is preferable because it can impart stable electrical characteristics to the transistor using it. However, if y1 is x When it becomes more than 3 times 1, the field-effect mobility of the transistor using the oxide semiconductor film 108b Since this would cause a decrease, it is preferable that y1 be less than 3 times x1.

[0173] When the oxide semiconductor film 108b is In-M-Zn oxide, the oxide semiconductor film 108b is formed In the target used for film formation, the atomic ratio of metal elements is In:M:Zn=x1: Let y1:z1 、 x1 / y1 is between 1 / 3 and 6, and furthermore, between 1 and 6. Furthermore, z1 / y1 is preferably between 1 / 3 and 6, and more preferably between 1 and 6. By setting z1 / y1 to between 1 and 6, the oxide semiconductor film 108b is configured as CAA as described later. C-OS formation becomes easier. A typical example of the atomic ratio of the target metal elements is I n:M:Zn=4:2:4.1, In:M:Zn=1:1:1.2, In:M:Zn=3 There are options such as :1:2, etc.

[0174] Furthermore, if the oxide semiconductor films 108a and 108c are In-M-Zn oxide, In a target used to form body films 108a and 108c, the number of atoms of the metal element If the ratio is In:M:Zn=x²:y²:z², then 、 x2 / y2 <x1 / y1であって、z 2 / y2 is preferably between 1 / 3 and 6, and more preferably between 1 and 6. Also, I By increasing the atomic ratio of M to n, the oxide semiconductor films 108a and 108c Because it is possible to increase the energy gap and decrease the electron affinity, y² / x² It is preferable that this ratio be 3 or more, or 4 or more. Representative atomic ratio of target metal elements. Examples include In:M:Zn=1:3:2, In:M:Zn=1:3:4, and In:M:Z n=1:3:5, In:M:Zn=1:3:6, In:M:Zn=1:4:2, In:M :Zn=1:4:4, In:M:Zn=1:4:5, In:M:Zn=1:5:5 etc. ru.

[0175] Furthermore, if the oxide semiconductor films 108a and 108c are In-M oxides, then M is divalent gold. By creating a composition that does not include group atoms (for example, zinc), it contains a spinel-type crystal structure. It is possible to form oxide semiconductor films 108a and 108c without oxide semiconductors. For example, In-Ga oxide films can be used as films 108a and 108c. Examples of In-Ga oxide films include In-Ga metal oxide targets (In:Ga= It can be formed by sputtering using 7:93). In order to deposit the body films 108a and 108c using a DC discharge sputtering method, When n:M=x:y [atomic ratio], y / (x+y) should be 0.96 or less, preferably. A value of 0.95 or less is appropriate, for example, 0.93.

[0176] Note that the atomic ratios of oxide semiconductor films 108a, 108b, and 108c are considered to be within the margin of error. This includes variations of plus or minus 40% in the above atomic ratio.

[0177] In Figures 6(A) and 6(B), the oxide semiconductor film 108 of transistor Tr1 is two layers and Although a three-layer stacked structure was given as an example, the oxide semiconductor film 12 of the transistor Tr2 A similar configuration may be used in case 8 as well.

[0178] Thus, the semiconductor device of the present invention may have a second gate electrode or an oxide semiconductor. The layered structure of the conductive film may be changed and applied. Furthermore, the transistor according to this embodiment is Each of the above structures can be freely combined.

[0179] <1-8. Method for Manufacturing Semiconductor Devices> Next, a method for manufacturing a semiconductor device 100 according to one aspect of the present invention will be described using Figures 8 to 17. I will explain.

[0180] Note that Figures 8(A), 9(A), 10(A), 11(A), 12(A), and 13 Figures (A), 14(A), 15(A), 16(A), and 17(A) show semiconductor devices. This is a top view illustrating the manufacturing method of 100, and is shown in Figures 8(B), 9(B), 10(B), and 11(B), Figure 12(B), Figure 13(B), Figure 14(B), Figure 15(B), Figure 16(B) Figure 17(B) is a cross-sectional view illustrating a method for manufacturing the semiconductor device 100.

[0181] First, a conductive film is formed on the substrate 102, and the conductive film is subjected to a lithography process and an etching process. The process is carried out to form a conductive film 104 that functions as the first gate electrode. An insulating film 106, which functions as a first gate insulating film, is formed on the film 104 (Figure 8(A)). (See (B)).

[0182] In this embodiment, a glass substrate is used as the substrate 102 and functions as the first gate electrode. As the conductive film 104, a tungsten film with a thickness of 100 nm is formed by sputtering. It is made possible. In addition, a silicon nitride film with a thickness of 400 nm and a film with a thickness of 50 nm are used as insulating film 106. A silicon oxide nitride film is formed by the PECVD method.

[0183] Furthermore, the silicon nitride film used as insulating film 106 shall have a layered structure. Specifically, The silicon nitride film consists of a first silicon nitride film, a second silicon nitride film, and a third silicon nitride film. A three-layer laminated structure with a film can be formed. An example of this three-layer laminated structure is as follows: It can be formed as follows.

[0184] For example, the first silicon nitride film is silane at a flow rate of 200 sccm, and silane at a flow rate of 2000 sccm. PE-CV uses sccm of nitrogen and ammonia gas at a flow rate of 100 sccm as raw material gases. It supplies power to the reaction chamber of apparatus D, controls the pressure inside the reaction chamber to 100 Pa, and uses a high frequency of 27.12 MHz. If you supply 2000W of power using a frequency power supply and form it to a thickness of 50nm, good.

[0185] The second silicon nitride film was a silane at a flow rate of 200 sccm, and a flow rate of 2000 sccm Nitrogen and ammonia gas at a flow rate of 2000 sccm are used as raw material gases in a PECVD apparatus. A 27.12 MHz high-frequency power supply is supplied to the reaction chamber, controlling the pressure inside the chamber to 100 Pa. By supplying 2000W of power using this method, the material can be formed to a thickness of 300nm.

[0186] The third silicon nitride film is a silane at a flow rate of 200 sccm, and a silane at a flow rate of 5000 sccm. A nitrogen atom at a concentration of 1 cm is supplied as a raw material gas to the reaction chamber of the PECVD apparatus, and the pressure inside the reaction chamber is set to 100. It is controlled to Pa and supplied with 2000W of power using a 27.12MHz high-frequency power supply, It should be formed so that the depth is 50 nm.

[0187] Furthermore, the first silicon nitride film, the second silicon nitride film, and the third silicon nitride film The substrate temperature during formation can be kept below 350°C.

[0188] By making the insulating film 106 a three-layer laminated structure of silicon nitride films, for example, conductive film 10 When a conductive film containing copper (Cu) is used in step 4, the following effects are achieved.

[0189] The first silicon nitride film suppresses the diffusion of copper (Cu) elements from the conductive film 104. Yes, it is possible. The second silicon nitride film has the function of releasing hydrogen and functions as a gate insulating film. The dielectric strength of the insulating film can be improved. The third silicon nitride film is the third silicon nitride Low hydrogen release from the first film, and diffusion of hydrogen released from the second silicon nitride film. It can be suppressed.

[0190] Next, an oxide semiconductor film 108 is formed on the insulating film 106 (see Figures 9(A) and 9(B)).

[0191] In this embodiment, an In-Ga-Zn metal oxide target (In:Ga:Zn=4: Using a 2:4.1 (atomic ratio), an oxide semiconductor film is formed by sputtering. Furthermore, the substrate temperature during the formation of the oxide semiconductor film was set to 170°C, and the film formation gas used during the formation was set to For this purpose, oxygen gas at a flow rate of 60 sccm and argon gas at a flow rate of 140 sccm are used. Subsequently, the oxide semiconductor film is processed into the desired shape to form an island-shaped oxide semiconductor film 1 Form O8. A wet etching apparatus is used to form the oxide semiconductor film.

[0192] Next, a conductive film is formed on the insulating film 106 and the oxide semiconductor film 108, and the conductive film is desired By processing it into this shape, conductive films 112a and 112b are formed. Then, insulating film 106 , oxide semiconductor film 108, and insulating films 114, 116 on conductive films 112a, 112b This is achieved (see Figures 10(A) and 10(B)).

[0193] In this embodiment, the conductive films 112a and 112b are tungsten films with a thickness of 50 nm. Then, a 100nm thick aluminum film and a 50nm thick titanium film are stacked in sequence. The layer film is deposited by sputtering.

[0194] Furthermore, after the formation of the conductive films 112a and 112b, the surface of the oxide semiconductor film 108 (back chip) The channel side may be cleaned. For example, the cleaning method may involve using an aqueous phosphoric acid solution. One example is cleaning using a can. This removes the deposits adhering to the surface of the oxide semiconductor film 108. Impurities (for example, elements contained in conductive films 112a and 112b) can be removed. However, this cleaning is not always necessary, and in some cases, it may not be required. .

[0195] Furthermore, either the step of forming conductive films 112a and 112b, or the cleaning step described above, In both cases, the region exposed from the conductive film 112a, 112b of the oxide semiconductor film 108. However, it may become thinner.

[0196] In this embodiment, a silicon oxide nitride film with a thickness of 20 nm is used as the insulating film 114. As 116, a silicon oxidizride film with a thickness of 200 nm was shaped using the PECVD method. To accomplish.

[0197] Furthermore, after forming the insulating film 114, the insulating film 116 is formed continuously without exposure to the atmosphere. It is preferable to do so. After forming the insulating film 114, do not open it to the atmosphere, and control the flow rate, pressure, and high of the raw material gas. By adjusting the frequency power and substrate temperature to one or more units, the insulating film 116 is formed continuously, The concentration of impurities originating from atmospheric components at the interface between the edge film 114 and the insulating film 116 is reduced. In addition, oxygen contained in the insulating films 114 and 116 is transferred to the oxide semiconductor film 108. This makes it possible to reduce the amount of oxygen vacancies in the oxide semiconductor film 108. .

[0198] In this embodiment, the insulating film 114 is set to a temperature of 220°C for holding the substrate 102. The raw materials are silane at a flow rate of 50 sccm and nitrous oxide at a flow rate of 2000 sccm. The pressure inside the processing chamber is set to 20 Pa, and the high-frequency power supplied to the parallel plate electrodes is 13.56 MHz. Hz, 100W (power density is 1.6 × 10⁻⁶) -2 W / cm 2 The PECVD method is used as follows: A silicon oxide nitride film is formed using this method.

[0199] As the insulating film 116, the substrate placed in the vacuum-evacuated processing chamber of the PECVD apparatus Maintain the temperature between 180°C and 350°C, introduce the raw material gas into the processing chamber, and adjust the pressure within the processing chamber. The pressure is set to 100 Pa or more and 250 Pa or less, more preferably 100 Pa or more and 200 Pa or less. , 0.17 W / cm² is applied to the electrode installed in the processing chamber. 2 More than 0.5W / cm 2 Below, further good The current level is 0.25 W / cm². 2 More than 0.35W / cm 2 The following conditions apply to supplying high-frequency power: This then forms a silicon oxide film or a silicon oxide-nitride film.

[0200] As for the film deposition conditions for the insulating film 116, the above pressure is used in the reaction chamber and the above power density is used in the high-frequency current By supplying power, the decomposition efficiency of the raw material gas in the plasma increases, and the amount of oxygen radicals increases. As the oxidation of the raw material gas progresses, the oxygen content in the insulating film 116 becomes less than the stoichiometric composition. The number also increases. On the other hand, in films formed at the above temperature, the bonding force between silicon and oxygen Because the bond is weak, some of the oxygen in the film is removed by the subsequent heat treatment. As a result, stoichiometric An oxide containing more oxygen than the theoretically required oxygen composition, with some of the oxygen being removed upon heating. An insulating film can be formed.

[0201] Furthermore, in the process of forming the insulating film 116, the insulating film 114 protects the oxide semiconductor film 108. It forms a film. Therefore, while reducing damage to the oxide semiconductor film 108, the power density is The insulating film 116 can be formed using high-frequency power.

[0202] Furthermore, in the film formation conditions for the insulating film 116, silicon-containing deposition gas against oxidizing gas By increasing the flow rate of the material, it is possible to reduce the amount of defects in the insulating film 116. ESR measurement revealed that g=2.001 originates from the dangling bond of silicon. The spin density of the signal is 6 × 10 17 spins / cm 3 Less than 3 × 10 17 spins / cm 3 The following is preferably 1.5 × 10 17 spins / cm 3 The following is missing It is possible to form an oxide insulating film with fewer depressions. As a result, the signal of transistor Tr1 It can enhance reliability.

[0203] Furthermore, after forming the insulating films 114 and 116, a heat treatment (hereinafter referred to as the first heat treatment) is performed. It is preferable to perform the following. The first heat treatment removes nitrogen acid contained in the insulating films 114 and 116. The amount of oxidized material can be reduced by the first heat treatment. Some of the oxygen contained in the oxide semiconductor film 108 is transferred to the oxide semiconductor film 108. This can reduce the amount of oxygen deficiency.

[0204] The temperature of the first heat treatment is typically less than 400°C, preferably less than 375°C, and Preferably, the temperature is 150°C to 350°C. The first heat treatment involves nitrogen, oxygen, and superdry Dry air (water content of 20 ppm or less, preferably 1 ppm or less, preferably 10 ppb) The procedure can be carried out under the atmosphere of air or a noble gas (argon, helium, etc.). Preferably, the above nitrogen, oxygen, ultra-dry air, or noble gas does not contain hydrogen, water, etc. For heat treatment, electric furnaces, RTA (Rapid Thermal Annealing), etc. are used. It is possible.

[0205] Next, an oxide semiconductor film 128 is formed on the insulating film 116 (see Figures 11(A) and 11(B)). .

[0206] In this embodiment, an In-Ga-Zn metal oxide target (In:Ga:Zn=4: Using a 2:4.1 (atomic ratio), an oxide semiconductor film is formed by sputtering. Furthermore, the substrate temperature during the formation of the oxide semiconductor film was set to 170°C, and the film formation gas used during the formation was set to For this purpose, oxygen gas at a flow rate of 60 sccm and argon gas at a flow rate of 140 sccm are used. Subsequently, the oxide semiconductor film is processed into the desired shape to form an island-shaped oxide semiconductor film 1 Form 28. A wet etching apparatus is used to form the oxide semiconductor film.

[0207] Next, conductive films 122a, 122b, and 122 are applied to the insulating film 116 and the oxide semiconductor film 128. 2c is formed, and then insulating film 116, oxide semiconductor film 128, and conductive film 122a, 1 Insulating films 124 and 126 are formed on 22b and 122c (see Figures 12(A) and 12(B)).

[0208] The conductive films 122a, 122b, and 122c are the conductive films 112a and 112b shown above. It can be formed by a similar method. Also, the insulating films 124 and 126 are as shown above. It can be formed by the same method as the insulating films 114 and 116.

[0209] Next, openings 182 reaching the conductive film 122a are formed in desired regions of the insulating films 124 and 126. This is done. Subsequently, a conductive film 130 is formed on the insulating film 126 and the conductive film 122a (Figure 13). (See (A) and (B)).

[0210] The opening 182 is formed using a dry etching apparatus or a wet etching apparatus. Furthermore, the conductive film 130 is an oxide (I) having indium, tin, and silicon. (Also called TSO) Target (In2O3:SnO2:SiO2=85:10:5 [weight) Using [%]), an ITSO film with a thickness of 100 nm is formed, and then it is processed into island shapes.

[0211] Next, an insulating film 126, an insulating film 134 which will be an insulating film on the conductive film 130, and an insulating film 136 A laminated film is formed with an insulating film. Subsequently, the conductive film 130 reaches a desired region of the laminated film. This forms an opening 184 (see Figures 14(A) and 14(B)).

[0212] As insulating film 134, a silicon oxide nitride film with a thickness of 200 nm was used by the PECVD method. It is formed by [doing this]. In addition, the insulating film 136 is a photosensitive acrylic-based organic film with a thickness of 1.5 μm. It forms a resin film.

[0213] The opening 184 is formed using a dry etching apparatus or a wet etching apparatus. ru.

[0214] Next, a conductive film is formed on the insulating film 136 and the conductive film 130, and the conductive film is processed into an island shape. This process forms a conductive film 138 (see Figures 15(A) and 15(B)).

[0215] In this embodiment, the conductive film 138 is an ITSO film with a thickness of 10 nm and a film with a thickness of 200 A reflective metal film of nm (here, a metal film having silver, palladium, and copper), and a thickness of 1 A laminated film with a 0 nm ITSO film is used. In addition, wet etching is used for processing the conductive film 138. A checking device is used.

[0216] Next, island-shaped insulating films 140 are formed on the insulating film 136 and the conductive film 138 (Figure 16(A )(see B)).

[0217] As the insulating film 140, a photosensitive polyimide-based organic resin film with a thickness of 1.5 μm is used. .

[0218] Next, an EL layer 142 is formed on the conductive film 138, and then the insulating film 140 and the EL layer 14 By forming the conductive film 144 on 2, the light-emitting element 160 is formed (Figure 17(A)(B)). reference).

[0219] The method for forming the light-emitting element 160 will be described in detail in Embodiment 3.

[0220] By following the above steps, the semiconductor device 100 shown in Figures 1(A) and 1(B) can be formed.

[0221] The configuration and methods shown in this embodiment can be appropriately combined with the configurations and methods shown in other embodiments. They can be used together.

[0222] (Embodiment 2) In this embodiment, a semiconductor device and a method for manufacturing a semiconductor device according to one aspect of the present invention are described below. This will be explained with reference to Figures 18 to 29.

[0223] <2-1. Example of Semiconductor Device Configuration 1> Figure 18(A) is a top view of a semiconductor device 200 according to one embodiment of the present invention, and Figure 18(B) is This corresponds to the cross-sectional view of the section between the dashed line A1 and A2 shown in Figure 18(A). Figure 18(B) shows a cross-section of transistor Tr1 in the direction of the channel length (L), and the transistor Includes a cross-section of Tr2 in the direction of the channel length (L).

[0224] The semiconductor device 100 shown in Figure 18(A)(B) includes transistor Tr1 and transistor It has transistor Tr1 and transistor Tr2, which overlap at least a portion of each other. Transistor Tr1 is a bottom-gate transistor, while transistor Tr2 is a top-gate transistor. It is a gate-structured transistor.

[0225] The region in which transistors Tr1 and Tr2 overlap at least partially is By incorporating this feature, the area required for transistor placement can be reduced.

[0226] Transistor Tr1 is connected to a conductive film 104 on a substrate 102, and the substrate 102 and conductive film 104 The insulating film 106 above, the oxide semiconductor film 108 on the insulating film 106, and the oxide semiconductor film 108 The conductive film 112a on top, the conductive film 112b on the oxide semiconductor film 108, and the oxide semiconductor film 1 08, insulating film 114 on conductive film 112a and conductive film 112b, and insulating film 114 on insulating film 114 Film 116, insulating film 118 on insulating film 116, insulating film 119 on insulating film 118, insulation It has an insulating film 210a on film 119 and a conductive film 212a on insulating film 210a.

[0227] Furthermore, transistor Tr2 has a conductive film 112c and an insulating film 114 on the conductive film 112c. , insulating film 116 on insulating film 114, insulating film 118 on insulating film 116, and insulating film 118 The insulating film 119, the oxide semiconductor film 208 on the insulating film 119, and the oxide semiconductor film 208 The insulating film 210b, the conductive film 212b on the insulating film 210b, and the oxide semiconductor film 208 and An insulating film 214 on the conductive film 212b, an insulating film 216 on the insulating film 214, and an insulating film 216 A conductive film 218a is provided and electrically connected to the oxide semiconductor film 208, and an insulating film 21 A conductive film 218b is provided on 6 and electrically connected to the oxide semiconductor film 208, and has ru.

[0228] As shown in Figures 18(A) and (B), oxide semiconductor film 108 and oxide semiconductor film 2 08 has overlapping regions.

[0229] The oxide semiconductor film 108 can be configured in the same way as shown in Embodiment 1. The oxide semiconductor film 208 has the same configuration as the oxide semiconductor film 128 shown in Embodiment 1. It can be done this way.

[0230] Therefore, either or both of transistors Tr1 and Tr2 The field effect mobility is 10 cm. 2 More preferably, transistor Tr1 and The field-effect mobility of either or both of transistors Tr2 is 30 cm 2 / Vs exceeds It becomes possible to do so.

[0231] For example, a transistor with high field-effect mobility, as described above, can be used to signal the gate signal of a display device. By using it in the gate driver that is generated, a display device with a narrow bezel (also called a narrow-bezel display) is provided. It can be used. Furthermore, the above-mentioned transistor with high field-effect mobility can be used in a display device. The source driver that supplies signals from the signal line (especially the source driver has By using it in a demultiplexer connected to the output terminal of a sub-register, it can be connected to a display device. A display device with a small number of connected wires can be provided. Also, the above field effect mobility Transistors with high performance are used for the selection transistors and drive transistors of the pixel circuits in the display device. To provide a display device with high display quality by using either or both of the sts. It is possible.

[0232] Furthermore, the semiconductor device 100 shown in Figures 18(A) and 18(B) is suitably used in the pixel circuit of a display device. This allows for the arrangement shown in Figures 18(A) and 18(B), which improves the pixel density of the display device. It becomes possible to increase the degree. For example, if the pixel density of the display device exceeds 1000 ppi, Alternatively, even if the pixel density of the display device exceeds 2000 ppi, Figure 18(A)(B By arranging the pixels as shown in the diagram, the aperture ratio can be increased.

[0233] Furthermore, when applying the semiconductor device 100 shown in Figures 18(A) and 18(B) to the pixel circuit of a display device... In this case, a configuration similar to the pixel circuit shown in Figure 2 can be used.

[0234] Furthermore, when the semiconductor device 100 shown in Figures 18(A) and 18(B) is applied to the pixels of a display device, For example, the channel length (L) and channel width (W) of a transistor, or the transistor The wiring and electrode widths connected to the transistor can be made relatively large. Compared to the case where transistors Tr1 and Tr2 are placed on the same plane, Figure 18(A As shown in (B), at least a portion of transistor Tr1 and transistor Tr2 By overlapping the pieces, the line width and other dimensions can be increased, thus reducing variations in processing dimensions. It becomes possible to reduce this.

[0235] Furthermore, in transistor Tr1 and transistor Tr2, either the conductive film or the insulating film is used. Since one or both can be used in common, the number of masks or the number of processes can be reduced. It is possible.

[0236] For example, in transistor Tr1, the conductive film 104 functions as the first gate electrode. Conductive film 112a functions as the source electrode, and conductive film 112b functions as the drain electrode. Furthermore, the conductive film 212a functions as a second gate electrode. Also, in transistor Tr1 And insulating film 106 acts as the first gate insulating film, insulating films 114, 116, 118 ,119 and 210a function as a second gate insulator. Also, transistor Tr2 In this configuration, the conductive film 112c functions as the first gate electrode, and the conductive film 218a functions as the source electrode. It functions as a second electrode, with conductive film 218b acting as the drain electrode and conductive film 212b acting as the second electrode It functions as an electrode. Also, in transistor Tr2, insulating films 114 and 116, 118 and 119 function as the first gate insulating film, and insulating film 210b is the second gate insulating film. It functions as a membrane.

[0237] In this specification, etc., insulating film 210a is referred to as the fourth insulating film, and insulating film 210b is referred to as the fifth insulating film. These are sometimes referred to as insulating films, respectively.

[0238] Furthermore, an insulating film 136 is provided on the insulating film 216 and the conductive films 218a and 218b. Furthermore, the insulating film 136 is provided with an opening 186 that reaches the conductive film 218b. A conductive film 138 is provided on the insulating film 136. The conductive film 138 is located at the opening 18 It is connected to the conductive film 218b via 6.

[0239] Furthermore, an insulating film 140, an EL layer 142, and a conductive film 144 are provided on the conductive film 138. Furthermore, the conductive film 138, the EL layer 142, and the conductive film 144 form the light-emitting element 16 0 is formed.

[0240] Thus, in one embodiment of the present invention, a bottom gate transistor and a top gate transistor are used. It can be used in combination with a gate-structured transistor.

[0241] Also, although not shown in the drawings, transistor Tr1 and shown in Figure 18(A)(B) The transistor Tr2 may also be an S-channel structure as described in Embodiment 1.

[0242] Furthermore, the semiconductor device 200 shown in this embodiment has transistors Tr1 and trans Tr2 and transistors Tr1 and Tr2 of the semiconductor device 100 shown in Embodiment 1 It can be used in combination with the Rangista Tr2.

[0243] As described above, a semiconductor device according to one aspect of the present invention has a stacked structure of multiple transistors, To reduce the footprint of the transistor. Also, in multiple transistors, the insulating film and By using one or both of the conductive films in common, the number of masks or process steps can be reduced. It can be reduced.

[0244] <2-2. Components of Semiconductor Devices> Next, the components included in the semiconductor device of this embodiment will be described in detail.

[0245] [Conductive film] The conductive films 212a, 212b, 218a, and 218b are the conductive films described in Embodiment 1. Film (conductive film 104, conductive film 112a, conductive film 112b, conductive film 122a, conductive film 122b By using the materials of conductive film 122c, conductive film 130, conductive film 138, and conductive film 144) This is possible. In particular, if an oxide conductor (OC) is used for the conductive films 212a and 212b, It is suitable because oxygen can be added to the insulating films 210a and 210b.

[0246] [Insulated film] Insulating films 118, 119, 214, 216, 210a, and 210b are as follows: Embodiment 1 The insulating film described (insulating film 106, insulating film 114, insulating film 116, insulating film 124, insulating film 1 Materials for 26, insulating film 134, insulating film 136, and insulating film 140 can be used.

[0247] In particular, if a silicon nitride film or a silicon nitride oxide film is used as the insulating film 118, It is suitable because it can suppress impurities entering transistor Tr1. Also, insulating film 119 As such, an oxide insulating film is preferred because it comes into contact with the oxide semiconductor film 208, and in particular silica oxide A silicon oxide film or silicon oxide nitride film is preferred. Also, as for insulating films 210a and 210b Preferably, it is an oxide insulating film, and the region contains an excess of oxygen compared to the stoichiometric composition. It is more preferable to have an (excess oxygen region). As for the insulating films 210a and 210b, acid A silicon oxide film or a silicon oxidizride film is preferable.

[0248] Furthermore, the insulating film 214 contains either hydrogen or nitrogen, or both. The edge film 214 contains nitrogen and silicon. The insulating film 214 also contains oxygen, hydrogen, water, and It has the ability to block metals such as potassium and alkaline earth metals. Oxide semiconductor film 2 When 08 comes into contact with the insulating film 214, either the hydrogen or nitrogen in the insulating film 214 is absorbed. Alternatively, both enter the oxide semiconductor film 208, and the carrier density of the oxide semiconductor film 208 This can be increased. Therefore, when the oxide semiconductor film 208 and the insulating film 214 are in contact... The region in the oxide semiconductor film 208 functions as either a source region or a drain region.

[0249] [Oxide semiconductor film] The oxide semiconductor film 208 is the oxide semiconductor film described in Embodiment 1 (oxide semiconductor Materials for film 108 and oxide semiconductor film 128 can be used.

[0250] <2-3. Method for Manufacturing Semiconductor Devices> Next, a method for manufacturing a semiconductor device 200 according to one aspect of the present invention will be described using Figures 19 to 29. I will explain.

[0251] Note that Figures 19(A), 20(A), 21(A), 22(A), 23(A), and Figure Figures 24(A), 25(A), 26(A), 27(A), 28(A), and 29( A) is a top view illustrating the method for manufacturing the semiconductor device 200, and Figures 19(B) and 20( B), Figure 21(B), Figure 22(B), Figure 23(B), Figure 24(B), Figure 25(B), Figure 2 Figures 6(B), 27(B), 28(B), and 29(B) show the fabrication of the semiconductor device 200. This is a cross-sectional view illustrating the method.

[0252] First, a conductive film is formed on the substrate 102, and the conductive film is subjected to a lithography process and an etching process. The process is carried out to form a conductive film 104 that functions as the first gate electrode. An insulating film 106, which functions as a first gate insulating film, is formed on the film 104 (Figure 19(A )(see B)).

[0253] In this embodiment, a glass substrate is used as the substrate 102 and functions as the first gate electrode. As the conductive film 104, a tungsten film with a thickness of 100 nm is formed by sputtering. It is made possible. In addition, a silicon nitride film with a thickness of 400 nm and a film with a thickness of 50 nm are used as insulating film 106. A silicon oxide nitride film is formed by the PECVD method.

[0254] Next, an oxide semiconductor film 108 is formed on the insulating film 106 (see Figures 20(A) and 20(B)). .

[0255] In this embodiment, an In-Ga-Zn metal oxide target (In:Ga:Zn=4: Using a 2:4.1 (atomic ratio), an oxide semiconductor film is formed by sputtering. Furthermore, the substrate temperature during the formation of the oxide semiconductor film was set to 170°C, and the film formation gas used during the formation was set to For this purpose, oxygen gas at a flow rate of 60 sccm and argon gas at a flow rate of 140 sccm are used. Subsequently, the oxide semiconductor film is processed into the desired shape to form an island-shaped oxide semiconductor film 1 Form O8. A wet etching apparatus is used to form the oxide semiconductor film.

[0256] Next, a conductive film is formed on the insulating film 106 and the oxide semiconductor film 108, and the conductive film is desired By processing into the shape, conductive films 112a, 112b, and 112c are formed. After that, the insulating film is formed. Insulation on the border film 106, oxide semiconductor film 108, and conductive films 112a, 112b, and 112c They form films 114, 116, 118, and 119 (see Figures 21(A) and 21(B)).

[0257] In this embodiment, conductive films 112a, 112b, and 112c are made of tan material with a thickness of 50 nm. A gusten film, a 100 nm thick aluminum film, and a 50 nm thick titanium film are layered in sequence. The layered laminated film is deposited by sputtering.

[0258] Furthermore, in this embodiment, a silicon oxidizride film with a thickness of 20 nm is used as the insulating film 114. A silicon oxidizride film with a thickness of 200 nm is used as insulating film 116, and a silicon oxidizride film with a thickness of 1 A silicon nitride film of 00 nm thickness is used as insulating film 119, and silicon nitride film of 50 nm thickness is used. The films are formed using the PECVD method.

[0259] Furthermore, after forming the insulating films 114, 116, 118, and 119, the first heat treatment is performed. This is preferable. The first heat treatment removes some of the oxygen contained in the insulating films 114 and 116 from the acid. The oxygen is transferred to the oxide semiconductor film 108, reducing the amount of oxygen vacancies contained in the oxide semiconductor film 108. It is possible.

[0260] Next, an oxide semiconductor film 208 is formed on the insulating film 119 (see Figures 22(A) and 22(B)). .

[0261] In this embodiment, an In-Ga-Zn metal oxide target (In:Ga:Zn=4: Using a 2:4.1 (atomic ratio), an oxide semiconductor film is formed by sputtering. Furthermore, the substrate temperature during the formation of the oxide semiconductor film was set to 170°C, and the film formation gas used during the formation was set to For this purpose, oxygen gas at a flow rate of 60 sccm and argon gas at a flow rate of 140 sccm are used. Subsequently, the oxide semiconductor film is processed into the desired shape to form island-shaped oxide semiconductor films 2 Form O8. A wet etching apparatus is used to form the oxide semiconductor film.

[0262] Next, a laminated film of the insulating film and the conductive film is formed on the insulating film 119 and the oxide semiconductor film 208. Then, the laminated film is processed into a desired shape, thereby forming island-shaped insulating films 210a, 21 0b and island-shaped conductive films 212a and 212b are formed. Then, insulating film 119 and oxide Insulating films 214 and 216 are formed on the semiconductor film 208 and the conductive films 212a and 212b. See Figures 23(A) and 23(B).

[0263] In this embodiment, the insulating films 210a and 210b are 50 nm thick silicon oxidnitridation The conductive film is formed using a PECVD apparatus. Furthermore, the conductive films 212a and 212b are... A 200 nm thick oxide semiconductor film is formed using a sputtering apparatus. The oxide semiconductor film used has the same composition as the oxide semiconductor film 208. Also, insulating film 2 For step 14, a silicon nitride film with a thickness of 100 nm is formed using a PECVD apparatus. Furthermore, as the insulating film 216, a silicon oxide nitride film with a thickness of 200 nm is used in a PECVD apparatus. It is formed using [this method].

[0264] Furthermore, a portion of the oxide semiconductor film 208 and the conductive films 212a and 212b are separated by an insulating film. By contact with 214, either or both of the hydrogen and nitrogen in the insulating film 214 are added. This process results in the material becoming an oxide conductor (OC).

[0265] Furthermore, insulating films 210a and 210b are masked by conductive films 212a and 212b, respectively. It is formed in a self-consistent manner.

[0266] Next, openings 28 that reach the oxide semiconductor film 208 in desired regions of the insulating films 214 and 216 Forms 2a and 282b (see Figure 24(A)(B)).

[0267] The openings 282a and 282b are formed using a dry etching apparatus or a wet etching apparatus. Use a device.

[0268] Next, the insulating film 216 and the oxide semiconductor film 20 are placed to cover the openings 282a and 282b. A conductive film is formed on 8, and the conductive film is processed into island shapes, thereby forming conductive films 218a, 218b It forms (see Figures 25(A) and 25(B)).

[0269] Conductive films 218a and 218b consist of a tungsten film with a thickness of 100 nm and a film with a thickness of 200 nm. A copper film of thickness m is formed by sputtering.

[0270] Next, an insulating film 136 is formed on the insulating film 216 and the conductive films 218a and 218b. Subsequently, by processing a desired region of the insulating film 136, an opening 186 is formed that reaches the conductive film 218b. It forms (see Figures 26(A) and 26(B)).

[0271] In this embodiment, the insulating film 136 is a photosensitive acrylic-based organic film with a thickness of 1.5 μm. It forms a resin film.

[0272] Next, a conductive film is formed on the insulating film 136 and the conductive film 218b, and the conductive film is processed into an island shape. This forms a conductive film 138 (see Figures 27(A) and 27(B)).

[0273] In this embodiment, the conductive film 138 is an ITSO film with a thickness of 10 nm and a film with a thickness of 200 A reflective metal film of nm (here, a metal film having silver, palladium, and copper), and a thickness of 1 A laminated film with a 0 nm ITSO film is used. In addition, wet etching is used for processing the conductive film 138. A checking device is used.

[0274] Next, island-shaped insulating films 140 are formed on the insulating film 136 and the conductive film 138 (Figure 28(A )(see B)).

[0275] As the insulating film 140, a photosensitive polyimide-based organic resin film with a thickness of 1.5 μm is used. .

[0276] Next, an EL layer 142 is formed on the conductive film 138, and then the insulating film 140 and the EL layer 14 By forming the conductive film 144 on 2, the light-emitting element 160 is formed (Figure 29(A)(B)). reference).

[0277] The method for forming the light-emitting element 160 will be described in detail in Embodiment 3.

[0278] By following the above steps, the semiconductor device 200 shown in Figures 18(A) and 18(B) can be manufactured.

[0279] The configuration and methods shown in this embodiment can be appropriately combined with the configurations and methods shown in other embodiments. They can be used together.

[0280] (Embodiment 3) In this embodiment, a semiconductor device and a method for manufacturing a semiconductor device according to one aspect of the present invention are described below. This will be explained with reference to Figures 30 to 45.

[0281] <3-1. Example of Semiconductor Device Configuration 1> Figure 30(A) is a top view of a semiconductor device 300 according to one embodiment of the present invention, and Figure 30(B) is This corresponds to a cross-sectional view of the section between the dashed line A1 and A2 shown in Figure 30(A). Figure 30(B) shows a cross-section of transistor Tr1 in the direction of the channel length (L), and the transistor Includes a cross-section of Tr2 in the direction of the channel length (L).

[0282] Furthermore, in Figure 30(A), in order to avoid complexity, the configuration of the semiconductor device 300 is shown. Some elements (such as insulating films that function as gate insulating films) and some of the symbols of the components have been omitted. This is illustrated in the diagram. Note that in the top view of the semiconductor device, Figure 30 is also used in subsequent drawings. (A) is similar to the case where some of the components and some of the reference numerals of the components are omitted in the illustration. ru.

[0283] The semiconductor device 300 shown in Figures 30(A) and 30(B) includes a transistor Tr1 and a transistor It has Tr2, and transistors Tr1 and Tr2 are at least partially connected to each other. It has an overlapping region. Note that transistor Tr1 is a top-gate structure transistor. Furthermore, transistor Tr2 is a bottom-gate transistor.

[0284] The region in which transistors Tr1 and Tr2 overlap at least partially is By incorporating this feature, the area required for transistor placement can be reduced.

[0285] Transistor Tr1 consists of an insulating film 306 on substrate 302 and an oxide semiconductor on insulating film 306. Body film 308, insulating film 310 on oxide semiconductor film 308, and conductive film 32 on insulating film 310 0, and an insulating film 306, an oxide semiconductor film 308, and an insulating film 314 on a conductive film 320. Furthermore, the oxide semiconductor film 308 overlaps with the conductive film 320 and is in contact with the insulating film 310. The channel region 308i and the source region 308s that are in contact with the insulating film 314 and the insulating film 314 It has a drain region 308d.

[0286] Furthermore, transistor Tr1 has an insulating film 316 on the insulating film 314, and insulating film 314 and an insulating film. Through the opening 341a provided in the edge film 316, oxide semi-oxide is released in the source region 308s. A conductive film 312a is electrically connected to the conductive film 308, and insulating films 314 and 316 Through the provided opening 341b, the oxide semiconductor film 30 in the drain region 308d The conductive film 312b is electrically connected to 8, and the insulating film 316, conductive film 312a, and conductive film It has an insulating film 318 on 312b.

[0287] Furthermore, transistor Tr2 has a conductive film 312b and an insulating film 318 on the conductive film 312b. , an oxide semiconductor film 328 on an insulating film 318, and a conductive film 322a on the oxide semiconductor film 328 And, conductive film 322b on oxide semiconductor film 328, oxide semiconductor film 328, conductive film 322 a, and insulating film 324 on conductive film 322b, insulating film 326 on insulating film 324, insulating film It has a conductive film 330 on 326. The conductive film 330 is on insulating films 324 and 326. It is connected to the conductive film 322a through the provided opening 382.

[0288] As shown in Figures 30(A) and 30(B), the oxide semiconductor film 308 and the oxide semiconductor film 3 28 has overlapping regions. Note that, as shown in Figures 30(A)(B), the transition The channel region formed in the oxide semiconductor film 308 of transistor Tr1, and the channel region formed in the oxide semiconductor film 308 of transistor Tr2 It is preferable that the channel regions formed in the oxide semiconductor film 328 do not overlap with each other. .

[0289] The channel region of transistor Tr1 and the channel region of transistor Tr2 are relative to each other. When they overlap, one transistor operating can affect the other. There is an effect. To avoid this effect, between transistor Tr1 and transistor Tr2 A configuration that increases the spacing, or a conductive film between transistors Tr1 and Tr2. One example is a configuration that includes [a certain feature]. However, in the former configuration, the semiconductor device becomes thicker. Therefore, for example, when forming a semiconductor device 300 on a flexible substrate, flexibility and other properties are important. This can sometimes become a problem. Also, in the case of the latter configuration, the number of steps for forming the conductive film increases, and the former Similar to the previous configuration, the increased thickness of the semiconductor device can sometimes cause problems.

[0290] On the other hand, in a semiconductor device 300 according to one aspect of the present invention, a transistor Tr1 and a transistor The transistor Tr2 is placed on top of each other, and the channel regions of each transistor are provided without overlapping. Furthermore, by overlapping a portion of the oxide semiconductor film in which the channel region is formed, The placement area of ​​the ZISTA can be suitably reduced.

[0291] Furthermore, oxide semiconductor film 308 and oxide semiconductor film 328 are composed of In and M(M) respectively. It has Al, Ga, Y, or Sn, and Zn. For example, oxide semiconductor film 308 In the oxide semiconductor film 328, the atomic ratio of In is greater than the atomic ratio of M. It is preferable to have a region. However, the semiconductor device according to one aspect of the present invention is not limited thereto. A configuration having a region where the atomic ratio of In is less than the atomic ratio of M, or the atomic ratio of In The configuration may have the same region as the atomic ratio of M.

[0292] Furthermore, oxide semiconductor film 308 and oxide semiconductor film 328 have the same composition, or composition It is preferable that they are roughly the same. Composition of oxide semiconductor film 308 and oxide semiconductor film 328 By making them the same, it becomes possible to reduce manufacturing costs. However, this is one aspect of the present invention. The semiconductor device is not limited to this, and includes an oxide semiconductor film 308 and an oxide semiconductor film 328. The composition may be varied.

[0293] In oxide semiconductor film 308 and oxide semiconductor film 328, the atomic ratio of In is greater than the atomic ratio of M. Having a larger region allows for the field effect transfer of transistors Tr1 and Tr2. The degree can be increased. Specifically, transistors Tr1 and Tr2 If the field effect mobility of either one or both is 10 cm 2 / Vs, more preferably exceeding Vs. This refers to the field effect transfer of either or both transistors Tr1 and Tr2. The degree is 30cm 2 It becomes possible to exceed / Vs.

[0294] For example, a transistor with high field-effect mobility, as described above, can be used to signal the gate signal of a display device. By using it in the gate driver that is generated, a display device with a narrow bezel (also called a narrow-bezel display) is provided. It can be used. Furthermore, the above-mentioned transistor with high field-effect mobility can be used in a display device. The source driver that supplies signals from the signal line (especially the source driver has By using it in a demultiplexer connected to the output terminal of a sub-register, it can be connected to a display device. A display device with a small number of connected wires can be provided. Also, the above field effect mobility Transistors with high performance are used for the selection transistors and drive transistors of the pixel circuits in the display device. To provide a display device with high display quality by using either or both of the sts. It is possible.

[0295] Furthermore, the semiconductor device 300 shown in Figures 30(A) and 30(B) is suitably used in the pixel circuit of a display device. This allows for the arrangement shown in Figures 30(A) and 30(B), which improves the pixel density of the display device. It becomes possible to increase the pixel density. For example, if the pixel density of a display device is 1000 ppi (pixels If the pixel density exceeds 1 per inch, or if the pixel density of the display device exceeds 2000 ppi, Even in this case, by using the arrangement shown in Figures 30(A) and 30(B), the aperture ratio of the pixels can be increased. It can be done. Note that ppi is a unit that represents the number of pixels per inch.

[0296] <3-2. Pixel Circuits of Display Devices> Here, the semiconductor device 300 shown in Figures 30(A) and 30(B) is applied to the pixel circuit of the display device. An example of this case will be explained using Figure 31.

[0297] Figure 31 shows an example of applying the semiconductor device 300 to the pixel circuit of a display device. This is a circuit diagram.

[0298] The semiconductor device 300 shown in Figure 31 includes transistor Tr1, transistor Tr2, and It has a quantitative element Cs1 and a light-emitting element 360. Note that in Figure 31, semiconductor device 3 This illustrates a configuration where two 00s are adjacent in the column direction. The semiconductor device 300 is a pixel (or sub-pixel). It functions as one of the elements (also called an element). Furthermore, the capacitive element Cs1 is shown in Figure 30. Although not shown in the diagram, for example, the conductive film 312b of transistor Tr1 and the transistor It can be formed using the parasitic capacitance between Tr2 and the conductive film 322b.

[0299] Furthermore, in the circuit diagram shown in Figure 31, data line D is used to write data signals to the pixels. L_Y-1, data line DL_Y which writes a data signal to an adjacent pixel, and light-emitting element Anode line ANODE_X-1 that supplies potential to the child, and a line that supplies potential to the adjacent light-emitting element The anode line ANODE_X and the scan line GL_X that supplies the scan signal to the pixel are shown. It is.

[0300] One of the source and drain electrodes of transistor Tr1 is connected to the data line DL_Y-1. Electrically connected. Furthermore, the first gate electrode and the second gate of transistor Tr1 The electrodes are electrically connected to the scan line GL_X. Transistor Tr1 is the data signal It has a function to control data writing.

[0301] One of the pair of electrodes of the capacitive element Cs1 is connected to the source electrode and drain of the transistor Tr1. It is electrically connected to the other electrode. Also, the other electrode of the pair of electrodes of the capacitive element Cs1 is connected to the transistor. It is electrically connected to the second gate electrode (also called the back gate electrode) of the zista Tr2. The capacitive element Cs1 functions as a retention capacitor, holding the data that has been written to it.

[0302] One of the source and drain electrodes of transistor Tr2 is connected to the anode wire ANODE_ It is electrically connected to the X-1.

[0303] One of the pair of electrodes of the light-emitting element 360 is the source electrode and drain electrode of transistor Tr2. One electrode is electrically connected to the other electrode, and the other electrode is electrically connected to the cathode wire. Furthermore, one of the pair of electrodes of the light-emitting element 360 is connected to the other of the pair of electrodes of the capacitive element Cs1. They are electrically connected.

[0304] The above configuration applies the semiconductor device 300 shown in Figures 30(A) and 30(B) to the pixels of a display device. This is just one example.

[0305] <3-3. Semiconductor device configuration> Let us once again explain the semiconductor device 300 shown in Figures 30(A) and 30(B). Figures 30(A) and 30(B) When the semiconductor device 300 shown is applied to the pixels of a display device, for example, the transistor's chat Channel length (L) and channel width (W), or the wiring and electrode wires connected to the transistor. The width and other dimensions can be made relatively large. For example, transistor Tr1 and transistor T Compared to the case where r2 and are placed on the same plane, as shown in Figures 30(A) and 30(B), By overlapping at least a portion of transistors Tr1 and Tr2, the line width Because these can be enlarged, it becomes possible to reduce variations in processed dimensions.

[0306] Furthermore, in transistor Tr1 and transistor Tr2, either the conductive film or the insulating film is used. Since one or both can be used in common, the number of masks or the number of processes can be reduced. It is possible.

[0307] For example, in transistor Tr1, the conductive film 320 functions as a gate electrode, and The film 312a functions as the source electrode, and the conductive film 312b functions as the drain electrode. Furthermore, in transistor Tr1, the insulating film 310 functions as a gate insulating film. In transistor Tr2, the conductive film 312b functions as the first gate electrode, and Film 322a functions as the source electrode, and conductive film 322b functions as the drain electrode. The film 330 functions as a second gate electrode. Also, in transistor Tr2, The edge film 318 functions as the first gate insulating film, and insulating films 324 and 326 function as the second gate insulating film. It functions as a border membrane.

[0308] In this specification, etc., insulating film 310 is referred to as the first insulating film, and insulating film 318 as the second insulating film. The edge film and insulating films 324 and 326 are sometimes referred to as the third insulating film, respectively.

[0309] Furthermore, an insulating film 334 and an insulating film 336 on the insulating film 334 are provided on the conductive film 330. Furthermore, the insulating films 334 and 336 are provided with openings 384 that reach the conductive film 330. Furthermore, a conductive film 338 is provided on the insulating film 336. Note that the conductive film 338 is It is connected to the conductive film 330 through the opening 384.

[0310] Furthermore, an insulating film 340, an EL layer 342, and a conductive film 344 are provided on the conductive film 338. The insulating film 340 covers a portion of the side edge of the conductive film 338, and conducts between adjacent pixels. The film 338 has a function to prevent short circuits. Furthermore, the EL layer 342 has a light-emitting function. Furthermore, the conductive film 338, the EL layer 342, and the conductive film 344 constitute the light-emitting element 360. The conductive film 338 functions as one electrode of the light-emitting element 360, and the conductive film 344 is It functions as the other electrode of the light-emitting element 360.

[0311] Thus, in one embodiment of the present invention, a top-gate transistor and a bottom gate transistor are used. It can be used in combination with a gate-structured transistor.

[0312] As described above, a semiconductor device according to one aspect of the present invention has a stacked structure of multiple transistors, To reduce the footprint of the transistor. Also, in multiple transistors, the insulating film and By using one or both of the conductive films in common, the number of masks or process steps can be reduced. It can be reduced.

[0313] <3-4. Configuration of the gate electrode> Furthermore, as shown in Figures 30(A) and 30(B), transistor Tr2 has two gate electrodes. This is the configuration.

[0314] Here, the effect of a configuration with two gate electrodes is shown in Figures 30(A)(B) and 30(B). We will use example 2 to provide the explanation.

[0315] Figure 32 is a cross-sectional view of the section between the dashed line B1-B2 shown in Figure 30(A). This corresponds to the above. Figure 32 also includes a cross-section of transistor Tr2 in the channel width (W) direction.

[0316] As shown in Figure 32, the oxide semiconductor film 328 is connected to the conductive film 312b and the conductive film 330. It is sandwiched between two conductive films that are positioned opposite each other and function as two gate electrodes. The lengths of 312b and the conductive film 330 in the channel width direction are, respectively, those of the oxide semiconductor film 328. The entire oxide semiconductor film 328 is longer than the length in the channel width direction, and the insulating film 318, 32 4, It is covered by conductive film 312b and conductive film 330 via 326.

[0317] In other words, conductive films 312b and 330 extend from the side edge of the oxide semiconductor film 328. It also has an outer region.

[0318] By using this configuration, the oxide semiconductor film 328 contained in transistor Tr2 The conductive film 312b and conductive film 330 can electrically surround the area. Like Tr2, the channel is formed by the electric fields of the first and second gate electrodes. The transistor device structure electrically surrounds the oxide semiconductor film in which the region is formed. This can be called a rounded channel (S-channel) structure.

[0319] Since transistor Tr2 has an S-channel structure, the first gate electrode is The conductive film 312b, which functions in this way, effectively induces an electric field in the oxide semiconductor to create a channel. Because it can be applied to the conductive film 328, the current driving capability of transistor Tr2 is improved. This makes it possible to obtain high on-current characteristics. Furthermore, it is possible to increase the on-current. Therefore, it becomes possible to miniaturize transistor Tr2. The conductive film 312b functions as the first gate electrode and the conductive film 312b functions as the second gate electrode. Because it has a structure surrounded by a conductive film 330, its mechanical strength can be increased.

[0320] Note that the transistor Tr2 shown in Figure 30(B) functions as a second gate electrode. The film 330 is a conductive film that functions as the source or drain electrode of transistor Tr2. The configuration has, but is not limited to, an electrical connection to 322a. The gate electrode of one electrode may be connected to the second gate electrode. In this case, the insulating film is connected to the first gate electrode. By providing openings at 318, 324, and 326, a conductive element functions as a second gate electrode. The film 330 is electrically connected to the conductive film 312b, which functions as the first gate electrode at the opening. They are connected to each other. Therefore, the same potential is applied to the conductive film 312b and the conductive film 330.

[0321] <3-5. Components of Semiconductor Devices> Next, the components included in the semiconductor device of this embodiment will be described in detail.

[0322] [substrate] There are no major restrictions on the material of the substrate 302, but it should at least be able to withstand subsequent heat treatment. It must have heat resistance. For example, glass substrates, ceramic substrates, quartz substrates, etc. A fire substrate or the like may be used as substrate 302. Alternatively, silicon or silicon carbide may be used as the material. Single-crystal semiconductor substrates, polycrystalline semiconductor substrates, and compound semiconductors such as silicon germanium are used as materials. It is also possible to apply substrates, SOI substrates, etc., and semiconductor elements are provided on these substrates. The prepared material may be used as substrate 302. Note that a glass substrate may be used as substrate 302. If available, 6th generation (1500mm x 1850mm), 7th generation (1870mm x 220 0mm), 8th generation (2200mm x 2400mm), 9th generation (2400mm x 280 By using large-area substrates such as 0mm, 10th generation (2950mm x 3400mm), Large-scale display devices can be manufactured.

[0323] Furthermore, a flexible substrate is used as the substrate 302, and the semiconductor device 300 is directly mounted on the flexible substrate. A release layer may be formed between the substrate 302 and the semiconductor device 300. The delamination layer is separated from the substrate 302 after the semiconductor device is partially or completely completed on it. It can be used to transfer to other substrates. In this case, the semiconductor device 300 is heat resistant. It can be mounted on inferior or flexible substrates.

[0324] [Conductive film] Conductive film 312a, conductive film 312b, conductive film 320, conductive film 322a, conductive film 322b, The conductive films 330, 338, and 344 are chromium (Cr) and copper (Cu). Aluminum (Al), gold (Au), silver (Ag), zinc (Zn), molybdenum (Mo) Tantalum (Ta), Titanium (Ti), Tungsten (W), Manganese (Mn), Nickel Metallic elements selected from iron (Ni), iron (Fe), and cobalt (Co), or the aforementioned metals These are formed using alloys composed of elements, or alloys combining the aforementioned metallic elements. It is possible.

[0325] Also, conductive film 312a, conductive film 312b, conductive film 320, conductive film 322a, conductive film 32 2b, conductive film 330, conductive film 338, and conductive film 344 contain indium and tin. Oxides, oxides containing tungsten and indium, tungsten, indium and zinc Oxides having titanium and indium, oxides having titanium, indium and tin Oxides containing indium and zinc, oxides containing silicon, indium and tin By applying oxide conductors such as oxides containing indium, gallium, and zinc, It can also be done this way.

[0326] In particular, the above-mentioned oxide conductors are preferably used for conductive films 320 and 330. Yes, it is possible. Here, we will explain oxide conductors. In this specification, etc., oxide conductors This may also be called OC (Oxide Conductor). Examples of oxide conductors include: For example, if an oxygen vacancy is formed in an oxide semiconductor and hydrogen is added to the oxygen vacancy, the vicinity of the conduction band... A donor level is formed. As a result, the oxide semiconductor becomes highly conductive and turns into a conductor. Oxide semiconductors that have been made conductive can be called oxide conductors. Generally, oxide semiconductors Conductors have a large energy gap and are therefore transparent to visible light. On the other hand, oxidation A conductor is an oxide semiconductor that has a donor level near the conduction band. Therefore, oxide Conductors exhibit little influence from absorption due to donor levels, and their absorption is similar to that of oxide semiconductors for visible light. It has light-transmitting properties.

[0327] Also, conductive film 312a, conductive film 312b, conductive film 322a, conductive film 322b, conductive film 3 30, conductive film 338, and conductive film 344 contain Cu-X alloy films (where X is Mn, Ni, Cr Fe, Co, Mo, Ta, or Ti may be applied. Using a Cu-X alloy film Therefore, since it can be processed using a wet etching process, manufacturing costs can be reduced. This is the result.

[0328] In particular, conductive film 312a, conductive film 312b, conductive film 322a, conductive film 322b, and conductive One or more of the films 330 can preferably be made from the Cu-X alloy films described above. Yes. As the Cu-X alloy film, a Cu-Mn alloy film is particularly preferred.

[0329] Also, conductive film 312a, conductive film 312b, conductive film 320, conductive film 322a, conductive film 32 2b and one or more of the conductive film 330 contain, among the above-mentioned metal elements, particularly Selected from aluminum, copper, titanium, tungsten, tantalum, and molybdenum. It is preferable to have one or more of these.

[0330] Also, conductive film 312a, conductive film 312b, conductive film 320, conductive film 322a, conductive film 32 2b and one or more of the conductive films 330 contain nitrogen and tantalum, so-called nitrogen It is preferable to use a tantalum nitride film. This tantalum nitride film is conductive and also contains copper Furthermore, it has high barrier properties against hydrogen. In addition, the tantalum nitride film has further protection against itself Because hydrogen is released in small amounts, the metal film in contact with the oxide semiconductor film 308, or the oxide semiconductor film It can be most preferably used as a metal film in the vicinity of 308.

[0331] [Insulated film] Insulating film 306, insulating film 314, insulating film 316, insulating film 318, insulating film 324, insulating film 3 26. The insulating film 334, insulating film 336, and insulating film 340 are silicon oxide film, oxide Silicon nitride film, silicon nitride oxide film, silicon nitride film, aluminum oxide film, HAF oxide nium film, yttrium oxide film, zirconium oxide film, gallium oxide film, tantalum oxide film , magnesium oxide film, lanthanum oxide film, cerium oxide film, and neodymium oxide film (one of these) Each of the insulating layers, including the upper layer, can be used.

[0332] Furthermore, the insulating film 306 functions as a blocking film that suppresses oxygen permeation. For example, insulating film 314, insulating film 316, oxide semiconductor film 308, oxide semiconductor film 328, When one or more of the insulating film 324 and insulating film 326 have an excess oxygen region In this configuration, the insulating film 306 can suppress the permeation of oxygen.

[0333] Furthermore, contact with either or both of the oxide semiconductor film 308 and the oxide semiconductor film 328. The insulating film is preferably an oxide insulating film, and is applied in excess of the stoichiometric composition. It is more preferable to have a region containing oxygen (excess oxygen region). In other words, excess oxygen Oxide insulating films having elementary regions are insulating films that can release oxygen.

[0334] Furthermore, as an oxide insulating film having the above-mentioned excess oxygen region, for example, under an oxygen atmosphere Forming an insulating film, heat-treating the insulating film after deposition in an oxygen atmosphere, or insulating film after deposition The film can be formed by adding oxygen to the film. Another method involves adding oxygen to the insulating film after it has been formed. Plasma treatment is preferred for this purpose.

[0335] Furthermore, it functions as an insulating film for the gates of transistors Tr1 and Tr2. Hafnium oxide may be used for the film. When using nium, the following effects are produced.

[0336] Hafnium oxide has a higher dielectric constant compared to silicon oxide and silicon oxide nitride. Therefore, compared to the case using silicon oxide, the thickness of the insulating film can be increased, thus tunnel This can reduce leakage current caused by current. In other words, a transistor with a small off-current It is possible to achieve this. Furthermore, hafnium oxide having a crystalline structure has an amorphous structure It has a higher dielectric constant compared to hafnium oxide, which has a low off-current. For use as a transistor, it is preferable to use hafnium oxide having a crystalline structure. Examples of crystal structures include monoclinic and cubic systems. However, one aspect of the present invention is... The term "sama" is not limited to these examples.

[0337] Furthermore, it functions as an insulating film for the gates of transistors Tr1 and Tr2. Silicon nitride may be used for the film. When using silicon nitride, the following effects are achieved. Compared to silicon oxide, silicon nitride has a higher dielectric constant. The efficiency is high, and the thickness required to obtain capacitance equivalent to silicon oxide is large, therefore the insulating film is Thick film formation is possible. Therefore, the dielectric strength of transistors Tr1 and Tr2 By suppressing the pressure drop and further improving the dielectric strength, transistor Tr1 and transistor This can suppress electrostatic discharge breakdown of Tr2.

[0338] Furthermore, insulating films 310, 316, 318, 324, and 326 are oxide semiconductor films 308 and It has the function of supplying oxygen to one or both of the oxide semiconductor films 328. Furthermore, insulating films 310, 316, 318, 324, and 326 contain oxygen. 310 and 324 are insulating films that can permeate oxygen. Note that insulating film 310 is... A damage mitigation film for the oxide semiconductor film 308 when forming the conductive film 320 which will be formed later. Even if it functions, the insulating film 324 will form the insulating film 326 later, and the oxide semiconductor It also functions as a damage-mitigating membrane for the body membrane 328.

[0339] The insulating films 310 and 324 have a thickness of 5 nm to 150 nm, preferably 5 nm. Silicon oxide, silicon oxide, silicon nitride, etc., with a wavelength of 50 nm or less can be used.

[0340] Furthermore, the insulating films 310 and 324 preferably have a low defect rate, and typically, ESR Measurement revealed that the signal appearing at g=2.001 originates from the silicon dangling bond. Pin density is 3 × 10 17 spins / cm 3 The following is preferable. This is an insulating film. If the defect density in 314 and 324 is high, oxygen will bond to the defects, and the insulating film 31 The amount of oxygen permeable at point 4 decreases.

[0341] Furthermore, insulating films 310 and 324 have low energy level densities due to nitrogen oxides. It can be formed using this. Furthermore, the level density due to the nitrogen oxide is the oxide semiconductor. The energy at the upper end of the valence band of a body membrane (Ev_os) and the energy at the lower end of the conduction band of an oxide semiconductor film It may be formed between the energy (Ec_os). As the oxide insulating film, nitrogen Silicon oxide nitride film with low oxide emission, or silicon oxide nitride film with low nitrogen oxide emission. Aluminum oxide films and the like can be used.

[0342] Furthermore, silicon oxidnitride films with low nitrogen oxide emissions can be analyzed using the temperature-controlled desorption gas analysis method (TD). In S), the membrane releases more ammonia than nitrogen oxides, and typically, Ammonia release amount is 1 × 10 18 cm -3 The above 5 x 10 19 cm -3 The following applies. The amount of ammonia released above is when the heat treatment temperature in TDS is between 50°C and 650°C. The total amount is below, or in the range of 50°C to 550°C. Also, the above ammonia emissions The output is the total amount converted to ammonia molecules in TDS.

[0343] Nitrogen oxides (NO x (where x is greater than 0 and less than or equal to 2, preferably between 1 and 2), typically NO2 or NO forms energy levels in insulating films 310, 324, etc. These energy levels are oxides. It is located within the energy gap of semiconductor films 308 and 328. Therefore, nitrogen oxides are located within the energy gap. The interface between insulating film 310 and oxide semiconductor film 308, or insulating film 324 and oxide semiconductor film When it diffuses to the interface of 328, the energy level traps electrons on the insulating film 310 and 324 side. This can occur. As a result, trapped electrons can be trapped in the insulating film 310 and the oxide semiconductor film 3 Because it remains near the interface of 08, or near the interface of the insulating film 324 and the oxide semiconductor film 328. This shifts the transistor's threshold voltage in the positive direction.

[0344] Furthermore, nitrogen oxides react with ammonia and oxygen during heat treatment. Insulating film 324 The nitrogen oxides contained in react with the ammonia contained in the insulating film 326 during the heat treatment. Therefore, nitrogen oxides contained in the insulating film 324 are reduced. At the interface of the oxide semiconductor film 328, electrons are less likely to be trapped.

[0345] By using the above oxide insulating film as insulating film 310 and 324, the transistor's structure It is possible to reduce the shift in the value voltage, thereby reducing fluctuations in the electrical characteristics of the transistor. It is possible.

[0346] Furthermore, the heat treatment in the transistor manufacturing process typically involves heating to temperatures between 300°C and 350°C. After heat treatment, the insulating films 310 and 324 were measured at an ESR of 100K or less, and the spectral properties obtained were obtained. In the cult, the first signal is when the g value is between 2.037 and 2.039, and the g value is 2.00 A second signal between 1 and 2.003, and a second signal with a g value between 1.964 and 1.966. Three signals are observed. Note that the split width between the first and second signals is Furthermore, the split width of the second and third signals is used in the X-band ESR measurement. is about 5 mT. Also, the total spin density of the first signal with a g-value of 2.037 or more and 2.039 or less, the second signal with a g-value of 2.001 or more and 2.003 or less, and the third signal with a g-value of 1.964 or more and 1.9 66 or less is less than 1×10 spins / cm 18 and typically less than 1×10 3 spins / cm 17 and more than 1×!0 3 spins / 18 cm is less than 1×10 3 spins / cm

[0347] In the ESR spectrum at 100 K or less, the total spin density of the first signal with a g-value of 2.037 or more and 2.039 or less, the second signal with a g-value of 2.001 or more and 2.003 or less, and the third signal with a g-value of 1.964 or more and 1.966 or less corresponds to the total spin density of the signal caused by nitrogen oxides (NO , where x is greater than 0 and 2 or less, preferably 1 or more and 2 or less). Representative examples of nitrogen oxides include nitric oxide, nitrogen dioxide, etc. That is, the smaller the total spin density of the first signal with a g-value of 2.037 or more and 2.039 or less, the second signal with a g-value of 2.00 1 or more and 2.003 or less, and the third signal with a g-value of 1.964 or more and 1.966 or less, the lower the content of nitrogen oxides contained in the oxide insulating film. x

[0348]

[0349] Also, the nitrogen concentration measured by SIMS in the above oxide insulating film is 6×10 20 atoms / cm 3 or less.

[0349] The substrate temperature is 220°C or more and 350°C or less, and PEC using silane and dinitrogen monoxide By forming the above oxide insulating film using the VD method, a dense and hard film is obtained. It can be formed.

[0350] The insulating film 314 has at least one of nitrogen or hydrogen. As for the insulating film 314, For example, nitride insulating films are used. Examples of nitride insulating films include silicon nitride. Formed using silicon nitride, aluminum nitride, aluminum nitride, etc. Yes, it is possible. The hydrogen concentration contained in insulating film 314 is 1 × 10⁻⁶. 22 atoms / cm 3 That's all. It is preferable that the insulating film 314 is located in the source region 308s of the oxide semiconductor film 308, and It is in contact with the drain region 308d. Also, the insulating film 314 has a region in contact with the conductive film 320. It has. Therefore, the source region 308s and drain region 308d are in contact with the insulating film 314. , and the hydrogen concentration in the conductive film 320 increases, source region 308s, drain region 308 d, and the carrier density of the conductive film 320 can be increased. Note that the source region 308s The drain region 308d and the conductive film 320 are each in contact with the insulating film 314. Therefore, there may be regions in the membrane where the hydrogen concentration is the same.

[0351] The insulating films 316, 318, and 326 contain more oxygen than satisfactorily satisfying the oxygen composition. It is formed using an oxide insulating film. It contains more oxygen than satisfactorily satisfying the stoichiometric composition. Oxide insulating films release some oxygen when heated. More oxygen than is needed to satisfy the stoichiometric composition. In oxide insulating films containing a large amount of oxygen, the amount of oxygen released in terms of oxygen molecules, as measured by TDS, is 1 .0 × 10 19 cm -3 Preferably 3.0 × 10 20 cm-3 That concludes the explanation. The amount of oxygen released as described above is when the heat treatment temperature in TDS is between 50°C and 650°C, This is the total amount in the range of 50°C to 550°C. Furthermore, the above oxygen release amount is calculated using TDS. This is the total amount converted to oxygen molecules.

[0352] The insulating films 316, 318, and 326 are preferably 30 nm to 500 nm thick. Alternatively, silicon oxide, silicon oxide, silicon nitride, etc., with a wavelength of 50 nm to 400 nm can be used. can.

[0353] Furthermore, it is preferable that the insulating films 316, 318, and 326 have a low defect rate, and typically ESR measurement reveals that it originates from the dangling bond of silicon, appearing at g=2.001. The signal spin density is 1.5 × 10⁻⁶ 18 spins / cm 3 Less than, and even 1 × 10 18 s pins / cm 3 The following is preferable:

[0354] Furthermore, insulating films 324 and 326 can be made of the same type of insulating material. In some cases, the interface between insulating film 324 and insulating film 326 cannot be clearly identified. Therefore, In this embodiment, the interface between the insulating film 324 and the insulating film 326 is shown with a dashed line. .

[0355] The insulating film 334 serves as a protective insulating film for transistors Tr1 and Tr2. To have the ability.

[0356] The insulating film 334 contains either hydrogen or nitrogen, or both. 34 contains nitrogen and silicon. The insulating film 334 contains oxygen, hydrogen, water, and alkali. It has the function of blocking metals, alkaline earth metals, etc. By providing an insulating film 334 Therefore, the diffusion of oxygen from the oxide semiconductor film 308 and the oxide semiconductor film 328 to the outside, and Diffusion of oxygen contained in the border films 310, 316, 324, and 326 to the outside, and oxidation from the outside This prevents hydrogen, water, and other substances from entering the semiconductor films 308 and 328.

[0357] For example, a nitride insulating film can be used as the insulating film 334. Examples include silicon nitride, silicon oxide nitride, aluminum nitride, and aluminum oxide nitride. These include:

[0358] [Oxide semiconductor film] The oxide semiconductor film 308 and the oxide semiconductor film 328 are made from the materials described above, respectively. It is possible to be there.

[0359] When oxide semiconductor film 308 and oxide semiconductor film 328 are In-M-Zn oxide, - Number of atoms of metal elements in the sputtering target used to deposit M-Zn oxide films The ratio preferably satisfies In > M. As for the ratio of the number of atoms of the basic elements, In:M:Zn = 2:1:3, In:M:Zn = 3:1:2, In Examples include :M:Zn=4:2:4.1.

[0360] Furthermore, in the case where oxide semiconductor film 308 and oxide semiconductor film 328 are In-M-Zn oxide... The metal elements of the sputtering target used to deposit In-M-Zn oxide films The atomic ratio may be a composition that satisfies In ≤ M. Gold in such a sputtering target The atomic ratio of the group elements is In:M:Zn = 1:1:1, and In:M:Zn = 1:1:1. 2, In:M:Zn=1:3:2, In:M:Zn=1:3:4, In:M:Zn=1: Examples include 3:6, etc.

[0361] Furthermore, oxide semiconductor film 308 and oxide semiconductor film 328 are each In-M-Zn acid In the case of nitriles, the sputtering target includes polycrystalline In-M-Zn oxide. Using a target is preferable. A target containing polycrystalline In-M-Zn oxide is used. This makes it easier to form crystalline oxide semiconductor films 308 and 328. The atomic ratio of the oxide semiconductor film 308 and oxide semiconductor film 328 to be formed is Each of these is the plus or minus atomic ratio of the metal elements contained in the sputtering target mentioned above. Includes a 40% variation in the oxide semiconductor film 308 and oxide semiconductor film 328. For the puttering target, an atomic ratio of In:Ga:Zn = 4:2:4.1 is used. In this case, the atomic ratio of the oxide semiconductor film 308 and oxide semiconductor film 328 to be deposited is: There are cases where Ga:Zn = 4:2:3 in the vicinity.

[0362] Furthermore, the oxide semiconductor film 308 and the oxide semiconductor film 328 have an energy gap of 2e It is V or higher, preferably 2.5eV or higher, more preferably 3eV or higher. By using an oxide semiconductor with a wide energy gap, transistor Tr1 and Trans This can reduce the off-current of Tr2.

[0363] Furthermore, the thickness of the oxide semiconductor film 308 and the oxide semiconductor film 328 is 3 nm or more. 200nm or less, preferably 3nm to 100nm, more preferably 3nm to 5nm The nm size should be 0 nm or less.

[0364] Furthermore, the hydrogen contained in oxide semiconductor film 308 and oxide semiconductor film 328 is a metal atom and It reacts with the oxygen it binds to to form water, and at the same time, the lattice (or the part from which oxygen has been removed) from which oxygen has been removed An oxygen vacancy is formed (in minutes). When hydrogen enters this oxygen vacancy, electrons, which act as carriers, are generated. In some cases, this can occur. Also, some of the hydrogen combines with oxygen that is bonded to a metal atom, and in the carrier It can generate certain electrons. Therefore, using an oxide semiconductor film containing hydrogen... Lampistors tend to exhibit normally-on characteristics. Therefore, oxide semiconductor film 308 and acid Preferably, the hydrogen content in the hydrogenated semiconductor film 328 is reduced as much as possible.

[0365] Specifically, SIMS analysis was performed on oxide semiconductor film 308 and oxide semiconductor film 328. The hydrogen concentrations obtained by each method are 2 × 10 20 atoms / cm 3 The following, preferably 5 x 10 19 atoms / cm 3 More preferably 1 × 10 19 atoms / cm 3 Below, 5 x 10 18 atoms / cm 3 The following is preferably 1 × 10 18 atoms / cm 3 The following is more preferable: 5 x 10 17 atoms / cm 3 More preferably, 1 × 1 0 16 atoms / cm 3 The following applies:

[0366] Furthermore, in oxide semiconductor film 308 and oxide semiconductor film 328, one of the Group 14 elements When silicon or carbon is included, oxide semiconductor film 308 and oxide semiconductor film 32 At 8, the oxygen vacancy increases, and it becomes n-type. Therefore, the oxide semiconductor film 308 and The silicon concentration obtained by SIMS analysis in oxide semiconductor film 328 is given by 2 ×10 18 atoms / cm 3 The following is preferably 2 × 10 17 atoms / cm 3 The following and do. Furthermore, SIMS analysis of oxide semiconductor film 308 and oxide semiconductor film 328 was obtained. The carbon concentrations are 2 × 10 18 atoms / cm 3 The following is preferably 2 × 10 1 7 atoms / cm 3 The following applies:

[0367] Furthermore, SIMS analysis was performed on oxide semiconductor film 308 and oxide semiconductor film 328. The resulting alkali metal or alkaline earth metal concentrations are 1 × 10⁻⁶ each. 18 Atom s / cm 3 The following is preferably 2 × 10 16 atoms / cm 3 The following applies: Alkali metals And alkaline earth metals may generate carriers when they combine with oxide semiconductors. The off-current of the transistor may increase. Therefore, the oxide semiconductor film 308 and Furthermore, reducing the concentration of alkali metals or alkaline earth metals in the oxide semiconductor film 328 is possible. preferable.

[0368] Furthermore, the oxide semiconductor film 308 and the oxide semiconductor film 328 can also be in a non-single crystal structure. Good. Non-single crystal structures include, for example, CAAC-OS (C Axis Aligne), which will be discussed later. d Crystalline Oxide Semiconductor), polycrystalline structure This includes microcrystalline or amorphous structures. In non-single-crystal structures, amorphous structures are the most defective. CAAC-OS has a high level density, while CAAC-OS has the lowest defect level density.

[0369] Furthermore, the various films mentioned above, such as conductive films, insulating films, and oxide semiconductor films, include spa Taring method, Plasma Chemical Vapor Deposition (PECVD) Chemical Vapor Deposition) method, thermal CVD (Chemical It can be formed by the (al Vapor Deposition) method. As a VD method, MOCVD (Metal Organic Chemical Vapor (r Deposition) method, or ALD (Atomic Layer Deposition) method. Examples include the tion method.

[0370] Thermal CVD is a film deposition method that does not use plasma, so defects can occur due to plasma damage. It has the advantage of never being accomplished.

[0371] In the thermal CVD method, the raw material gas and oxidizer are simultaneously introduced into the chamber, and the chamber is then cooled to the atmosphere. The film is formed by reacting the substrate near or on the substrate under pressure or reduced pressure, causing the film to deposit on the substrate. You may do so.

[0372] Furthermore, the ALD method maintains atmospheric pressure or reduced pressure inside the chamber and uses raw material gases for the reaction. It may be used to perform film formation.

[0373] Thermal CVD methods such as MOCVD and ALD are used for the conductive films, insulating films, and oxides of the above embodiments. It can form various films, such as semiconductor films, for example, an In-Ga-ZnO film. In such cases, trimethylindium, trimethylgallium, and dimethylzinc are used. The chemical formula for trimethylindium is In(CH3)3. The chemical formula for lium is Ga(CH3)3. The chemical formula for dimethylzinc is Zn(C It is H3)2. Furthermore, it is not limited to these combinations, and trimethylgallium can be substituted with Triethylgallium (chemical formula Ga(C2H5)3) can also be used, along with dimethylzinc. Alternatively, diethylzinc (chemical formula Zn(C2H5)2) can be used.

[0374] For example, when forming a hafnium oxide film using a film deposition apparatus that utilizes ALD, the solvent and a liquid containing hafnium precursor compounds (such as hafnium alkoxide or tetrakisdimethyl A raw material gas obtained by vaporizing hafnium amides (such as amide hafnium (TDMAH)) and an acid Two types of gases, ozone (O3), are used as nitrifying agents. Note that tetrakisdimethylamide is also used. The chemical formula for humium is Hf[N(CH3)2]4. Other material liquids include tetrahedron. Examples include lacs(ethylmethylamide)hafnium.

[0375] For example, when forming an aluminum oxide film using a film deposition apparatus that utilizes ALD, A liquid containing a medium and an aluminum precursor compound (such as trimethylaluminum (TMA)) Two types of gases are used: a vaporized raw material gas and H2O as an oxidizing agent. The chemical formula for aluminum is Al(CH3)3. Other material solutions include Tris( Dimethylamide) Aluminum, Triisobutylaluminum, Aluminum Tris(2 Examples include 2,6,6-tetramethyl-3,5-heptanedione).

[0376] For example, when forming a silicon oxide film using a film deposition apparatus that utilizes ALD, hexa Chlorodisilane is adsorbed onto the film-forming surface, and chlorine contained in the adsorbed material is removed, resulting in an oxidizing gas (O 2. A radical of nitrous oxide is supplied and reacted with the adsorbed material.

[0377] For example, when depositing a tungsten film using a film deposition apparatus that utilizes ALD, WF6 An initial tungsten film is formed using gas and B2H6 gas, and then WF6 gas and H2 A tungsten film is formed using gas. Note that SiH4 gas is used instead of B2H6 gas. You may use it.

[0378] For example, oxide semiconductor films, such as In-Ga-ZnO, can be deposited using an ALD (Advanced Laser Deposition) system. When forming a film, an In-O layer is formed using In(CH3)3 gas and O3 gas. Then, a GaO layer is formed using Ga(CH3)3 gas and O3 gas, and then Z A ZnO layer is formed using n(CH3)2 gas and O3 gas. Note the order of these layers. This is not the only example. Furthermore, these gases can be used to create In-Ga-O layers and In-Zn-O layers. Alternatively, a mixed compound layer such as a Ga-Zn-O layer may be formed. Note that Ar may be used instead of O3 gas. H2O gas obtained by bubbling with an inert gas such as can also be used, but O without H It is preferable to use gas 3. Also, instead of In(CH3)3 gas, In(C2H5) You may also use three gases. Alternatively, you can use Ga(C2H5)3 gas instead of Ga(CH3)3 gas. Alternatively, Zn(CH3)2 gas may be used.

[0379] <3-6. Example of Semiconductor Device Configuration 2> Next, a modified example of the semiconductor device 300 shown in Figures 30(A) and 30(B) will be shown using Figure 33. explain.

[0380] Figure 33 is a cross-sectional view of a modified example of the semiconductor device 300 shown in Figure 30(B).

[0381] Figure 33 shows the second gate electrode of transistor Tr2 in semiconductor device 300. This configuration does not include a conductive film 330 or an insulating film 334 on the conductive film 330. In Figure 33, the openings 382 provided in the insulating film 324 and insulating film 326, and the insulating film 33 4 and instead of the opening 384 provided in the insulating film 336, insulating film 324, insulating film 32 6, and an opening 383 is provided in the insulating film 336. In this way, the opening is 1 This approach is preferable because it reduces the number of manufacturing steps.

[0382] <3-7. Semiconductor device configuration example 3> Next, regarding a modified example of the semiconductor device 300 shown in Figures 30(A) and 30(B), see Figure 34(A)( This will be explained using B) and Figure 35(A)(B).

[0383] This section describes the stacked structure of oxide semiconductor films.

[0384] Figures 34(A)(B) show the channel length of transistor Tr2 in semiconductor device 300. This is a cross-sectional view in the L direction.

[0385] Figure 34(A) shows the oxide semiconductor film 328 of transistor Tr2, which is an oxide semiconductor A film 328a, an oxide semiconductor film 328b on the oxide semiconductor film 328a, and an oxide semiconductor film The configuration has an oxide semiconductor film 328c on 328b. That is, an oxide semiconductor film It has a three-layer laminated structure.

[0386] Figure 34(B) shows the oxide semiconductor film 328 of transistor Tr2, which is an oxide semiconductor The configuration comprises a film 328b and an oxide semiconductor film 328c on the oxide semiconductor film 328b. Yes, it exists. In other words, it has a stacked structure of two oxide semiconductor films.

[0387] An example of the band structure of the oxide semiconductor film 328 and the insulating film in contact with the oxide semiconductor film 328 is shown below. This is shown in Figures 35(A) and 35(B).

[0388] Figure 35(A) shows insulating film 318, oxide semiconductor films 328a, 328b, 328c, and This is an example of the band structure in the film thickness direction of a multilayer structure having an insulating film 324. Also, Figure 35(B ) has an insulating film 318, oxide semiconductor films 328b, 328c, and insulating film 324. This is an example of a band structure in the film thickness direction of a layered structure. Note that the band structure is shown for ease of understanding. The insulating film 318, oxide semiconductor films 328a, 328b, 328c, and insulating film 324 This shows the energy level (Ec) at the lower end of the guide.

[0389] Furthermore, Figure 35(A) shows a case where silicon oxide films are used as insulating film 318 and insulating film 324. The oxide semiconductor film 328a has an atomic ratio of metal elements of In:Ga:Zn=1:3:2. Using an oxide semiconductor film formed with a metal oxide target, the oxide semiconductor film 328 Let b be a metal oxide target with an atomic ratio of metal elements of In:Ga:Zn = 4:2:4.1. Using an oxide semiconductor film formed with a metal element as the oxide semiconductor film 328c Acids formed using a metal oxide target with an atomic ratio of In:Ga:Zn = 1:3:2 This is a band diagram of a configuration using a semiconductor film.

[0390] Furthermore, Figure 35(B) shows a case where silicon oxide films are used as insulating film 318 and insulating film 324. For the oxide semiconductor film 328b, the atomic ratio of the metal elements is In:Ga:Zn = 4:2:4. Using an oxide semiconductor film formed with a metal oxide target 1, an oxide semiconductor film 3 As 28c, the atomic ratio of metal elements is In:Ga:Zn=1:3:2, targeting metal oxides. This is a band diagram of a configuration using a metal oxide film formed using [a specific material].

[0391] As shown in Figures 35(A) and (B), the oxide semiconductor films 328a, 328b, and 328c Therefore, the energy levels at the lower end of the conduction band change smoothly. In other words, they change continuously. Alternatively, it can be said that they form a continuous bond. In order to have such a band structure, oxidation The interface between the monocrystalline semiconductor film 328a and the oxide semiconductor film 328b, or the oxide semiconductor film 328b At the interface between the oxide semiconductor film 328c, defect centers such as trap centers and recombination centers Assume that no impurities that would form a specific position exist.

[0392] To form a continuous junction on oxide semiconductor films 328a, 328b, and 328c, load Each film is deposited using a multi-chamber type film deposition apparatus (sputtering apparatus) equipped with a locking chamber. It is necessary to continuously stack the materials without exposing them to the atmosphere.

[0393] The configuration shown in Figures 35(A) and (B) allows the oxide semiconductor film 328b to form a well. Therefore, in the transistor using the above stacked structure, the channel region is an oxide semiconductor film 3 It can be seen that it is formed at 28b.

[0394] Furthermore, by providing oxide semiconductor films 328a and 328c, the trap levels are set to oxide It can be kept away from the semiconductor film 328b.

[0395] Furthermore, the trap level functions as a channel region in the conduction band of oxide semiconductor film 328b. The energy levels at the edges (Ec) can be farther from the vacuum level, and electrons can enter the trap levels. This makes it easier for electrons to accumulate. The accumulation of electrons in the trap level causes negative fixed This results in an electric charge, and the transistor's threshold voltage shifts to the positive direction. Therefore, , the trap level is more true than the energy level (Ec) of the lower end of the conduction band of the oxide semiconductor film 328b. It is preferable to configure it so that it approaches the empty level. By doing so, the trap level This makes it more difficult for electrons to accumulate, and it is possible to increase the on-current of the transistor. This can increase the field effect mobility.

[0396] Furthermore, oxide semiconductor films 328a and 328c are below the conduction band than oxide semiconductor film 328b. The edge energy levels are close to the vacuum level, typically in the conduction band of oxide semiconductor film 328b. The energy levels at the edge and the energy levels at the lower edge of the conduction band of the oxide semiconductor films 328a and 328c. The difference from the position is 0.15 eV or more, or 0.5 eV or more and 2 eV or less, or 1 eV The following applies: that is, the electron affinity of the oxide semiconductor films 328a and 328c, and the oxide semiconductor The difference with the electron affinity of the body membrane 328b is 0.15 eV or greater, or 0.5 eV or greater, and 2 It is less than or equal to eV, or less than 1 eV.

[0397] With this configuration, the oxide semiconductor film 328b becomes the main path for the current, It functions as a channel region. In addition, the oxide semiconductor films 328a and 328c are channel regions. The oxide semiconductor film 328b formed is composed of one or more metal elements. Since it is a semiconductor film, the interface between the oxide semiconductor film 328a and the oxide semiconductor film 328b, Alternatively, at the interface between the oxide semiconductor film 328b and the oxide semiconductor film 328c, interfacial scattering occurs. It is less likely to become stiff. Therefore, the movement of carriers is not hindered at the interface, so the transient The field effect mobility of the element increases.

[0398] Furthermore, the oxide semiconductor films 328a and 328c function as part of the channel region. To prevent this, use a material with sufficiently low conductivity. Alternatively, oxide semiconductor film 328a, 328c has an electron affinity (the difference between the vacuum level and the energy level at the bottom of the conduction band) that is high in oxide semiconductors. It is smaller than the conductive film 328b, and the energy level at the lower end of the conduction band is the same as that of the oxide semiconductor film 328b. A material with a difference (band offset) from the lower energy level of the conduction band is used. In order to suppress the occurrence of threshold voltage differences that depend on the magnitude of the rain voltage, The energy levels at the lower end of the conduction band of the monocrystalline semiconductor films 328a and 328c are such that the oxide semiconductor film 328 It is preferable to use a material whose energy level is closer to the vacuum level than the energy level at the lower end of the conduction band of b. For example Then, the energy level at the lower end of the conduction band of the oxide semiconductor film 328b and the oxide semiconductor film 328a The difference with the energy level at the lower end of the conduction band of 328c is 0.2 eV or more, preferably 0.5 eV. It is preferable that the value be eV or higher.

[0399] Furthermore, the oxide semiconductor films 328a and 328c do not contain a spinel-type crystal structure within the film. It is preferable that the oxide semiconductor films 328a and 328c contain a spinel-type crystal structure. If included, at the interface between the spinel-type crystal structure and other regions, conductive films 322a, 32 In some cases, the constituent elements of 2b may diffuse into the oxide semiconductor film 328b. If the conductive films 328a and 328c are CAAC-OS as described later, then conductive films 322a and 32 The blocking properties of the constituent elements of 2b, such as copper, become higher, which is preferable.

[0400] The thickness of the oxide semiconductor films 328a and 328c depends on the constituent elements of the conductive films 322a and 322b. A film thickness greater than or equal to that which can suppress diffusion into the oxide semiconductor film 328b, and provides insulation. The film thickness is set to a level that suppresses the supply of oxygen from film 324 to oxide semiconductor film 328b. For example, If the thickness of the oxide semiconductor films 328a and 328c is 10 nm or more, the conductive film 322a, This can suppress the diffusion of constituent elements of 322b into the oxide semiconductor film 328b. Furthermore, if the thickness of the oxide semiconductor films 328a and 328c is 100 nm or less, the insulating film 324 This allows for an effective supply of oxygen to the oxide semiconductor film 328b.

[0401] Oxide semiconductor films 328a and 328c are In-M-Zn oxide (where M is Al, Ga, Y, ma When (or Sn), by having M in a higher atomic ratio than In, the oxide semiconductor film 32 The energy gap between 8a and 328c can be increased, and the electron affinity can be decreased. Therefore, acid The difference in electron affinity with the ionized semiconductor film 328b can be controlled by the composition of M. In some cases, M is a metallic element with a strong bonding force with oxygen, so these elements are I Having a higher atomic ratio than n makes oxygen deficiency less likely to occur.

[0402] Furthermore, when the oxide semiconductor films 328a and 328c are In-M-Zn oxides, Zn The atomic ratio of In and M, excluding O, is preferably 50 atomic% In. Less than, M is higher than 50 atomic%, and more preferably In is 25 atomic% Less than 75, M is greater than 75 atomic%. Also, oxide semiconductor films 328a, 328c A gallium oxide film may be used instead.

[0403] Furthermore, in the case where the oxide semiconductor films 328a, 328b, and 328c are In-M-Zn oxide... Compared to oxide semiconductor film 328b, the M contained in oxide semiconductor films 328a and 328c The atomic ratio is large, and typically compared to the atoms contained in oxide semiconductor film 328b, The atomic ratio is 1.5 times or more, preferably 2 times or more, and more preferably 3 times or more higher. .

[0404] Furthermore, in the case where the oxide semiconductor films 328a, 328b, and 328c are In-M-Zn oxide... The oxide semiconductor film 328b is composed of In:M:Zn=x1:y1:z1 [atomic ratio], and the oxide semiconductor If the conductive films 328a and 328c are given the atomic ratio In:M:Zn=x2:y2:z2, y2 / x2 is greater than y1 / x1, preferably y2 / x2 is 1. It is 5 times or more. More preferably, y2 / x2 is 2 times or more greater than y1 / x1, and Preferably, y2 / x2 is 3 times or more, or 4 times or more, greater than y1 / x1. In the oxide semiconductor film 328b, if y1 is greater than or equal to x1, the oxide semiconductor film 328b This is preferable because it can impart stable electrical characteristics to the transistor using it. However, if y1 is x When it becomes more than 3 times 1, the field-effect mobility of the transistor using the oxide semiconductor film 328b Since this would cause a decrease, it is preferable that y1 be less than 3 times x1.

[0405] When the oxide semiconductor film 328b is In-M-Zn oxide, the oxide semiconductor film 328b is formed In the target used for film formation, the atomic ratio of metal elements is In:M:Zn=x1: Let y1:z1 、 x1 / y1 is between 1 / 3 and 6, and furthermore, between 1 and 6. Furthermore, z1 / y1 is preferably between 1 / 3 and 6, and more preferably between 1 and 6. By setting z1 / y1 to between 1 and 6, the oxide semiconductor film 328b is configured as CAA as described later. C-OS formation becomes easier. A typical example of the atomic ratio of the target metal elements is I n:M:Zn=4:2:4.1, In:M:Zn=1:1:1.2, In:M:Zn=3 There are options such as :1:2, etc.

[0406] Furthermore, if the oxide semiconductor films 328a and 328c are In-M-Zn oxide, In the target used to deposit body films 328a and 328c, the number of atoms of the metal element If the ratio is In:M:Zn=x²:y²:z², then 、 x2 / y2 <x1 / y1であって、z 2 / y2 is preferably between 1 / 3 and 6, and more preferably between 1 and 6. Also, I By increasing the atomic ratio of M to n, the oxide semiconductor films 328a and 328c Because it is possible to increase the energy gap and decrease the electron affinity, y² / x² It is preferable that this ratio be 3 or more, or 4 or more. Representative atomic ratio of target metal elements. Examples include In:M:Zn=1:3:2, In:M:Zn=1:3:4, and In:M:Z n=1:3:5, In:M:Zn=1:3:6, In:M:Zn=1:4:2, In:M :Zn=1:4:4, In:M:Zn=1:4:5, In:M:Zn=1:5:5 etc. ru.

[0407] Furthermore, if the oxide semiconductor films 328a and 328c are In-M oxides, then M is divalent gold. By creating a composition that does not include group atoms (for example, zinc), it contains a spinel-type crystal structure. It is possible to form oxide semiconductor films 328a and 328c without oxide semiconductors. For example, an In-Ga oxide film can be used as the films 328a and 328c. Examples of In-Ga oxides include In-Ga metal oxide targets (In:Ga=7 It can be formed by sputtering using :93). In order to deposit films 328a and 328c using a DC discharge sputtering method, When M = x:y [atomic ratio], y / (x+y) should be 0.96 or less, preferably 0. It's best to set it to 0.95 or less, for example, 0.93.

[0408] Note that the atomic ratios of oxide semiconductor films 328a, 328b, and 328c are considered to be within the margin of error. This includes variations of plus or minus 40% in the above atomic ratio.

[0409] Note that in Figures 34(A) and 34(B), the oxide semiconductor film 328 of transistor Tr2 is two layers. And a three-layer stacked structure was illustrated, but the oxide semiconductor film 3 of transistor Tr1 A similar configuration may be used in version 08 as well.

[0410] Thus, the semiconductor device of the present invention may have a second gate electrode or an oxide semiconductor. The layered structure of the conductive film may be changed and applied. Furthermore, the transistor according to this embodiment is Each of the above structures can be freely combined.

[0411] <3-8. Method for Manufacturing Semiconductor Devices> Next, a method for manufacturing a semiconductor device 300 according to one aspect of the present invention will be described using Figures 36 to 45. I will explain.

[0412] Note that Figures 36(A), 37(A), 38(A), 39(A), 40(A), and Figure Figures 41(A), 42(A), 43(A), 44(A), and 45(A) show semiconductors. This is a top view illustrating the method for manufacturing the apparatus 300, as shown in Figures 36(B), 37(B), and 38( B), Figure 39(B), Figure 40(B), Figure 41(B), Figure 42(B), Figure 43(B), Figure 4 Figures 4(B) and 45(B) are cross-sectional views illustrating a method for manufacturing the semiconductor device 300.

[0413] First, an insulating film 306 is formed on the substrate 302, and then an oxide semiconductor film is formed on the insulating film 306. Then, the oxide semiconductor film is processed into an island shape to form the oxide semiconductor film 308. This is achieved (see Figures 36(A) and 36(B)).

[0414] In this embodiment, a glass substrate can be used as the substrate 302.

[0415] The insulating film 306 can be deposited by sputtering, CVD, vapor deposition, or pulsed laser deposition. It can be formed using appropriate methods such as PLD, printing, and coating. For insulating film 306, a silicon nitride film with a thickness of 400 nm was formed using a PECVD apparatus. A silicon oxide-nitride film with a thickness of 50 nm is formed.

[0416] Alternatively, oxygen may be added to the insulating film 306 after it has been formed. The oxygen added to 6 can be oxygen radicals, oxygen atoms, oxygen atom ions, or oxygen molecular ions. These are some examples. In addition, methods of addition include ion doping, ion implantation, and plasma treatment. There are laws and regulations. Furthermore, after forming a film that suppresses oxygen desorption on the insulating film, insulation is applied through the film. Oxygen may be added to membrane 306.

[0417] As membranes that suppress the desorption of oxygen as described above, indium, zinc, gallium, tin, and aluminum are used. Chromium, tantalum, titanium, molybdenum, nickel, iron, cobalt, tungsten Selected metal elements, alloys containing the above-mentioned metal elements, and combinations of the above-mentioned metal elements alloys, metal nitrides having the above-mentioned metal elements, and metal oxides having the above-mentioned metal elements. This is formed using conductive materials such as metal nitride oxides having the aforementioned metal elements. It is possible.

[0418] Furthermore, when adding oxygen using plasma processing, the oxygen is excited by microwaves, resulting in a high-density acid By generating elementary plasma, the amount of oxygen added to the insulating film 306 can be increased. .

[0419] For oxide semiconductor film 308, sputtering, coating, pulsed laser deposition, It can be formed by laser ablation, thermal CVD, etc. For processing the conductive film 308, a mask is formed on the oxide semiconductor film by a lithography process. Afterward, a portion of the oxide semiconductor film can be etched using the mask to form the film. Alternatively, the element-separated oxide semiconductor film 308 may be directly formed using a printing method. .

[0420] When forming an oxide semiconductor film by sputtering, a power supply is required to generate the plasma. The device can use an RF power supply, AC power supply, DC power supply, etc., as appropriate. When forming oxide semiconductor films, the sputtering gas used is a noble gas (typically argon). ), oxygen, noble gases, and mixed gases of oxygen are used as appropriate. In this case, it is preferable to increase the gas ratio of oxygen to the noble gas.

[0421] Furthermore, when forming an oxide semiconductor film, for example, using the sputtering method, the substrate The temperature is between 150°C and 750°C, or between 150°C and 450°C, or below 200°C. By depositing an oxide semiconductor film at a temperature of 350°C or lower, the crystallinity can be enhanced. Therefore, it is preferable.

[0422] In this embodiment, the oxide semiconductor film 308 is made using a sputtering apparatus. In-Ga-Zn metal oxide (In:Ga:Zn) is used as the sputtering target. Using a ratio of 4:2:4.1 (atomic ratio), an oxide semiconductor film with a thickness of 40 nm is deposited.

[0423] Furthermore, after forming the oxide semiconductor film 308, a heat treatment is performed on the oxide semiconductor film 308. Dehydrogenation or dehydration may be performed. The heat treatment temperature is typically 150°C or higher for the substrate. Below the strain point, or between 250°C and 450°C, or between 300°C and 450°C. .

[0424] Heat treatment is performed using noble gases such as helium, neon, argon, xenon, krypton, or This can be done in an inert gas atmosphere containing nitrogen, or by heating in an inert gas atmosphere. Afterward, heating in an oxygen atmosphere may be performed. Note that hydrogen and water may be added to the above-mentioned inert atmosphere and oxygen atmosphere. It is preferable that certain substances are not included. The processing time should be between 3 minutes and 24 hours.

[0425] The heat treatment can be carried out using an electric furnace, an RTA device, etc. Therefore, heat treatment can be performed at a temperature above the strain point of the substrate for a short period of time. Processing time can be reduced.

[0426] A heat treatment is performed on an oxide semiconductor film while it is being deposited, or after the oxide semiconductor film has been formed. By performing this procedure, the hydrogen concentration obtained by secondary ion mass spectrometry in oxide semiconductor films is reduced. The degree is 5 x 10 19 atoms / cm 3 The following, or 1 × 10 19 atoms / cm 3 below , 5×10 18 atoms / cm 3 The following, or 1 × 10 18 atoms / cm 3 below, or 5 x 10 17 atoms / cm 3 The following, or 1 × 10 16 atoms / cm 3 Below It can be set below.

[0427] Next, an insulating film and a conductive film are formed on the insulating film 306 and the oxide semiconductor film 308, forming island-like structures. By processing, an insulating film 310 and a conductive film 320 are formed (see Figures 37(A) and (B)). .

[0428] As the insulating film 310, a silicon oxide film or a silicon oxide nitride film is used by the PECVD method. It can be formed using the following. In this case, the raw material gas is a silicon-containing sedimentary gas. And it is preferable to use an oxidizing gas. Typical examples of silicon-containing depositing gases include: Examples include silanes, disilanes, trisilanes, and silane fluorides. Oxidizing gases include oxygen and o Examples include nitrous oxide, dinitrogen monoxide, and nitrogen dioxide.

[0429] Furthermore, as the insulating film 310, the flow rate of the oxidizing gas is 20 times greater than the flow rate of the sedimenting gas. The pressure should be less than 100 times, or between 40 and 80 times, and the pressure inside the processing chamber should not exceed 100 Pa. By using the PECVD method with a pressure of full or 50 Pa or less, the amount of defects in oxidative nitride resin is reduced. A reconstituted film can be formed.

[0430] Furthermore, as the insulating film 310, a base placed in the vacuum-evacuated processing chamber of the PECVD apparatus The plate is kept at a temperature between 280°C and 400°C, and the raw material gas is introduced into the processing chamber. The pressure is set to 20 Pa or more and 250 Pa or less, more preferably 100 Pa or more and 250 Pa or less. Furthermore, under conditions where high-frequency power is supplied to electrodes provided in the processing chamber, the insulating film 310 is formed as This allows for the formation of a dense silicon oxide film or silicon oxide-nitride film.

[0431] Alternatively, the insulating film 310 may be formed using a plasma CVD method using microwaves. Microwaves refer to the frequency range from 300 MHz to 300 GHz. Furthermore, the electron temperature is low and the electron energy is low. Also, in the supplied power, the electrons are added It is used in small proportions for rapid dissociation and ionization, and can be used for the dissociation and ionization of a larger number of molecules. It is possible to excite a high-density plasma (high-density plasma). Therefore, This method produces an insulating film 310 with minimal plasma damage to the film surface and deposits, and with fewer defects. It is possible.

[0432] Furthermore, the insulating film 310 can be formed using a CVD method with organic silane gas. As for organic silane gases, ethyl silicate (TEOS: chemical formula Si(OC2H5)4), Tetramethylsilane (TMS: chemical formula Si(CH3)4), tetramethylcyclotetrasilane Roxane (TMCTS), Octamethylcyclotetrasiloxane (OMCTS), Hexa Methyldisilazane (HMDS), triethoxysilane (SiH(OC2H5)3), tri Silicon-containing compounds such as dimethylaminosilane (SiH(N(CH3)2)3) are used. It is possible to achieve high-coverage insulation by using the CVD method with organic silane gas. A film 310 can be formed.

[0433] In this embodiment, the insulating film 310 is made using a PECVD apparatus to create an oxide film with a thickness of 150 nm. A silicon nitride film is formed.

[0434] Furthermore, it is preferable that the conductive film 320 be formed of an oxide conductor (OC). During formation, oxygen is added from the conductive film 320 into the insulating film 310.

[0435] The conductive film 320 is formed using a sputtering method, which involves incorporating oxygen gas during formation. It is preferable to form it in an atmosphere. The conductive film 320 is formed in an atmosphere containing oxygen gas during formation. This allows for the appropriate addition of oxygen to the insulating film 310.

[0436] Furthermore, the conductive film 320 is made of the same material as the oxide semiconductor film 308 described above. It is possible.

[0437] In this embodiment, a sputtering apparatus is used to produce the conductive film 320. As a ring target, In-Ga-Zn metal oxide (In:Ga:Zn=5:1:7[ A conductive film with a thickness of 20 nm is deposited using the atomic ratio.

[0438] In this embodiment, the processing of the conductive film 320 and the insulating film 310 is performed by dryer. This is done using the swatching method.

[0439] Furthermore, during the processing of the conductive film 320 and the insulating film 310, there are regions where the conductive film 320 does not overlap. The thickness of the oxide semiconductor film 308 may become thinner.

[0440] Next, impurity elements are released from the insulating film 306, the oxide semiconductor film 308, and the conductive film 320. Add the additive.

[0441] Methods for adding impurity elements include ion doping, ion implantation, and plasma treatment. These include the following. In the case of plasma treatment, the plasma is created in a gas atmosphere containing the added impurity elements. By generating and performing plasma treatment, impurity elements can be added. Examples of devices that generate plasma include dry etching equipment, ashing equipment, and plasma A CVD apparatus, a high-density plasma CVD apparatus, etc., can be used.

[0442] The raw material gases for impurity elements are B2H6, PH3, CH4, N2, NH3, and Al. Using H3, AlCl3, SiH4, Si2H6, F2, HF, H2, and one or more noble gases It is possible to dilute B2H6, PH3, N2, NH3, AlH with a noble gas. 3. One or more of AlCl3, F2, HF, and H2 can be used. Diluted with a noble gas. B2H6, PH3, N2, NH3, AlH3, AlCl3, F2, HF, and H2 By adding impurity elements to the oxide semiconductor film 308 and the conductive film 320 using one or more of these elements, One or more of the following are oxides: noble gases, hydrogen, boron, carbon, nitrogen, fluorine, phosphorus, sulfur, and chlorine. It can be added to the conductive film 308 and the conductive film 320.

[0443] Alternatively, after adding a noble gas, B2H6, PH3, CH4, N2, NH3, AlH3, AlCl3, SiH4, Si2H6, F2, HF, and H2 are used to form one or more oxide semiconductor films. O8 and conductive film 320 may also be added.

[0444] Alternatively, B2H6, PH3, CH4, N2, NH3, AlH3, AlCl3, SiH4 After adding one or more of Si2H6, F2, HF, and H2, the noble gas is applied to the oxide semiconductor film 3 O8 and conductive film 320 may also be added.

[0445] The addition of impurity elements can be controlled by appropriately setting injection conditions such as acceleration voltage and dose amount. For example, when adding argon using the ion implantation method, the acceleration voltage is 10kV or more, or 100kV. Below V, the dose is 1 × 10⁻⁶. 13 ions / cm 2 The above 1 x 10 16 ions / cm 2 Below You can simply set it to below, for example, 1 × 10 14 ions / cm 2 This is how it should be done. Also, ion injection When adding phosphate ions using the induction method, the acceleration voltage is 30kV and the dose is 1 × 10⁻⁶. 13 ion s / cm 2 The above 5 x 10 16 ions / cm 2 The following is sufficient; for example, 1 × 10 15 ions / cm 2 That's all you need to do.

[0446] Furthermore, in this embodiment, as an impurity element, an algonium is added using a doping device. The compound is added to the oxide semiconductor film 308 and the conductive film 320. The example given is one in which argon is added as an impurity element, but it is not limited to this example. For example, a configuration in which nitrogen is added may also be used. Also, for example, a process in which impurity elements are added. It is not necessary to do so.

[0447] Next, the insulating film 314 is formed on the insulating film 306, the oxide semiconductor film 308, and the conductive film 320. This is achieved. Furthermore, by forming the insulating film 314, the oxide semiconductor film 3 in contact with the insulating film 314 08 is the source region 308s and the drain region 308d. It is also in contact with the insulating film 314. The oxide semiconductor film 308 that does not contact the insulating film 310, in other words, the oxide semiconductor film 308 that is in contact with the insulating film 310 The channel area becomes 308i. This results in a channel area of ​​308i and a source area of ​​308s. And an oxide semiconductor film 308 having a drain region 308d is formed (Figure 38(A)). (See (B)).

[0448] The insulating film 314 is formed by selecting a material that can be used for the insulating film 314. Yes, it is possible. In this embodiment, as the insulating film 314, a PECVD apparatus is used to create a film with a thickness of 1 A silicon nitride film with a thickness of 00 nm is formed.

[0449] By using a silicon nitride film as the insulating film 314, the conductive film 3 in contact with the insulating film 314 20, hydrogen and nitrogen in the silicon nitride film in the source region 308s and drain region 308d Either one or both of the elements enter, and the conductive film 320, source region 308s, and Dre This can increase the carrier density in region 308d.

[0450] Next, an insulating film 316 is formed on the insulating film 314.

[0451] The insulating film 316 is formed by selecting a material that can be used for the insulating film 316. Yes, it is possible. In this embodiment, as the insulating film 316, a PECVD apparatus is used to create a film with a thickness of 3 A silicon oxide-nitride film with a thickness of 00 nm is formed.

[0452] Next, a mask is formed on the insulating film 316 by lithography at a desired position, and then the insulating film By etching 316 and a portion of the insulating film 314, the opening reaches the source region 308s. A mouth portion 341a and an opening 341b that reaches the drain region 308d are formed (Figure 38). (See (A) and (B)).

[0453] A method for etching insulating film 316 and insulating film 314 is the wet etching method. And / or a dry etching method may be used as appropriate. In this embodiment, The insulating film 316 and insulating film 314 are processed using a dry etching method.

[0454] Next, a conductive film is formed on the insulating film 316 so as to cover the openings 341a and 341b. After forming a mask at the desired location using a lithography process, a portion of the conductive film is etched. This process forms conductive films 312a and 312b (see Figures 38(A) and 38(B)).

[0455] The conductive films 312a and 312b are those that can be used for conductive films 312a and 312b. It can be formed by selecting the material. In this embodiment, conductive films 312a and 312b Then, using a sputtering apparatus, a 50nm thick titanium film and a 400nm thick aluminum film were used. A laminated film is formed consisting of a nium film and a 100 nm thick titanium film.

[0456] The processing method for the conductive films 312a and 312b is a wet etching method and / or a dry etching method. A dry etching method can be used as appropriate. In this embodiment, a dry etching method is used. Using this method, the conductive film is processed to form conductive films 312a and 312b.

[0457] By following the above steps, transistor Tr1 can be fabricated.

[0458] Furthermore, the films that make up transistor Tr1 (insulating film, oxide semiconductor film, conductive film, etc.) are Puttering method, chemical vapor deposition (CVD), vacuum deposition, pulsed laser deposition (PLD) It can be formed using the ) method, ALD (atomic layer deposition) method, or by coating or printing. It can be formed by the following methods. Film deposition methods include sputtering and plasma chemical vapor deposition. The multiplicative CVD (PECVD) method is typical, but thermal CVD can also be used. As an example of thermal CVD, M One example is OCVD (organometallic vapor deposition).

[0459] Thermal CVD is a method in which the chamber is subjected to atmospheric pressure or reduced pressure, and the raw material gas and oxidizer are simultaneously processed. The film is formed by sending the material into a chamber, reacting it near or on the substrate, and depositing it onto the substrate. To do so, since thermal CVD is a film deposition method that does not generate plasma, It has the advantage of not generating defects through damage.

[0460] Furthermore, the ALD method maintains atmospheric pressure or reduced pressure inside the chamber and uses raw material gases for the reaction. The film is formed by introducing the material into a chamber, allowing it to react, and repeating this process. The material is inactivated along with the raw material gas. A carrier gas (such as argon or nitrogen) may be introduced. For example, type 2 The raw material gases of type 1 or more may be supplied to the chamber in sequence. In this case, if multiple types of raw material gases are mixed To prevent this from happening, after the reaction of the first raw material gas, an inert gas is introduced, and then the second raw material gas is introduced. Alternatively, instead of introducing an inert gas, the first raw material gas can be discharged by vacuum evacuation. After that, a second raw material gas may be introduced. The first raw material gas is adsorbed and reacts on the surface of the substrate. A first layer is formed, and a second raw material gas introduced later is adsorbed and reacts, so that the second layer becomes the first layer. A thin film is formed by stacking layers on top of each other. The desired thickness is achieved by controlling the order of gas introduction. By repeating this process multiple times, a thin film with excellent step coverage can be formed. The thickness can be adjusted by the number of times gas is introduced, allowing for precise film thickness control. It is capable of and is suitable for fabricating miniature FETs.

[0461] Thermal CVD methods such as MOCVD can be used for the conductive films, insulating films, oxide semiconductor films, and metals mentioned above. It can form films such as oxide films, for example, when forming an In-Ga-Zn-O film. It contains trimethylindium (In(CH3)3) and trimethylgallium (Ga(CH3) )3) and dimethylzinc (Zn(CH3)2) are used. The combination is not limited to these. Instead of trimethylgallium, triethylgallium (Ga(C2H5)3) is used. It is also possible to use diethylzinc (Zn(C2H5)2) instead of dimethylzinc. can.

[0462] For example, when forming a hafnium oxide film using a film deposition apparatus that utilizes ALD, the solvent and a liquid containing a hafnium precursor (such as hafnium alkoxide or tetrakisdimethylamide) Hafnium (TDMAH, Hf[N(CH3)2]4) and tetrakiss (ethylmethylamine) The raw material gas is a vaporized hafnium amide (such as hafnium), and ozone is used as an oxidizer. Two types of gases (O3) are used.

[0463] For example, when forming an aluminum oxide film using a film deposition apparatus that utilizes ALD, A liquid containing a medium and an aluminum precursor (trimethylaluminum (TMA, Al(CH3)) 3) etc.) are vaporized raw material gases, and two types of gases are used as oxidizers: H2O. The materials include tris(dimethylamide)aluminum, triisobutylaluminum, Aluminum tris(2,2,6,6-tetramethyl-3,5-heptanedione) There is.

[0464] For example, when forming a silicon oxide film using a film deposition apparatus that utilizes ALD, hexa Chlorodisilane is adsorbed onto the film-forming surface, and radicals of oxidizing gases (O2, nitrous oxide) are removed. It is supplied and reacted with the adsorbed material.

[0465] For example, when depositing a tungsten film using a film deposition apparatus that utilizes ALD, WF6 The initial tungsten film is formed by sequentially introducing gas and B2H6 gas, and then WF6 gas and A tungsten film is formed using H2 gas. Note that SiH4 gas can be used instead of B2H6 gas. You may also use "S".

[0466] For example, oxide semiconductor films, such as In-Ga-Zn-, can be deposited using an ALD-based film deposition system. When forming an O film, an In-O layer is formed using In(CH3)3 gas and O3 gas. Then, a GaO layer is formed using Ga(CH3)3 gas and O3 gas, and then Z A ZnO layer is formed using n(CH3)2 gas and O3 gas. Note the order of these layers. This is not the only example. Furthermore, these gases can be used to create In-Ga-O layers and In-Zn-O layers. Alternatively, a mixed compound layer such as a Ga-Zn-O layer may be formed. Note that Ar gas can be used instead of O3 gas. H2O gas obtained by bubbling water with an inert gas such as can also be used, but it does not contain H. It is preferable to use O3 gas.

[0467] Next, an insulating film 318 is formed on the insulating film 316 and the conductive films 312a and 312b.

[0468] The insulating film 318 can be deposited using sputtering, CVD, vapor deposition, or pulsed laser deposition. It can be formed using appropriate methods such as PLD, printing, and coating. For insulating film 318, a silicon nitride film with a thickness of 400 nm was formed using a PECVD apparatus. A silicon oxide-nitride film with a thickness of 50 nm is formed.

[0469] Alternatively, oxygen may be added to the insulating film 318 after it has been formed. The oxygen added to 8 can be oxygen radicals, oxygen atoms, oxygen atom ions, or oxygen molecular ions. These are some examples. In addition, methods of addition include ion doping, ion implantation, and plasma treatment. There are laws and regulations. Furthermore, after forming a film that suppresses oxygen desorption on the insulating film, insulation is applied through the film. Oxygen may be added to membrane 318.

[0470] As membranes that suppress the desorption of oxygen as described above, indium, zinc, gallium, tin, and aluminum are used. Chromium, tantalum, titanium, molybdenum, nickel, iron, cobalt, tungsten Selected metal elements, alloys containing the above-mentioned metal elements, and combinations of the above-mentioned metal elements alloys, metal nitrides having the above-mentioned metal elements, and metal oxides having the above-mentioned metal elements. This is formed using conductive materials such as metal nitride oxides having the aforementioned metal elements. It is possible.

[0471] Furthermore, when adding oxygen using plasma processing, the oxygen is excited by microwaves, resulting in a high-density acid By generating elementary plasma, the amount of oxygen added to the insulating film 318 can be increased. .

[0472] Furthermore, the silicon nitride film used as the insulating film 318 has a layered structure. Specifically, The silicon nitride film consists of a first silicon nitride film, a second silicon nitride film, and a third silicon nitride film. A three-layer laminated structure with a film can be formed. An example of this three-layer laminated structure is as follows: It can be formed as follows.

[0473] For example, the first silicon nitride film is silane at a flow rate of 200 sccm, and silane at a flow rate of 2000 sccm. PE-CV uses sccm of nitrogen and ammonia gas at a flow rate of 100 sccm as raw material gases. It supplies power to the reaction chamber of apparatus D, controls the pressure inside the reaction chamber to 100 Pa, and uses a high frequency of 27.12 MHz. If you supply 2000W of power using a frequency power supply and form it to a thickness of 50nm, good.

[0474] The second silicon nitride film was a silane at a flow rate of 200 sccm, and a flow rate of 2000 sccm Nitrogen and ammonia gas at a flow rate of 2000 sccm are used as raw material gases in a PECVD apparatus. A 27.12 MHz high-frequency power supply is supplied to the reaction chamber, controlling the pressure inside the chamber to 100 Pa. By supplying 2000W of power using this method, the material can be formed to a thickness of 300nm.

[0475] The third silicon nitride film is a silane at a flow rate of 200 sccm, and a silane at a flow rate of 5000 sccm. A nitrogen atom at a concentration of 1 cm is supplied as a raw material gas to the reaction chamber of the PECVD apparatus, and the pressure inside the reaction chamber is set to 100. It is controlled to Pa and supplied with 2000W of power using a 27.12MHz high-frequency power supply, It should be formed so that the depth is 50 nm.

[0476] Furthermore, the first silicon nitride film, the second silicon nitride film, and the third silicon nitride film The substrate temperature during formation can be kept below 350°C.

[0477] By making the insulating film 318 a three-layer laminated structure of silicon nitride films, for example, the conductive film 31 When a conductive film containing copper (Cu) is used for 2a and 312b, the following effects are achieved.

[0478] The first silicon nitride film suppresses the diffusion of copper (Cu) from the conductive films 312a and 312b. It can be controlled. The second silicon nitride film has the function of releasing hydrogen and gate insulation. The dielectric strength of insulating films that function as films can be improved. The third silicon nitride film is the The hydrogen release from the third silicon nitride film is small, and the release from the second silicon nitride film is small. This can suppress the diffusion of hydrogen.

[0479] Next, an oxide semiconductor film 328 is formed on the insulating film 318 (see Figures 39(A) and 39(B)). .

[0480] In this embodiment, an In-Ga-Zn metal oxide target (In:Ga:Zn=4: Using a 2:4.1 (atomic ratio), an oxide semiconductor film is formed by sputtering. Furthermore, the substrate temperature during the formation of the oxide semiconductor film was set to 170°C, and the film formation gas used during the formation was set to For this purpose, oxygen gas at a flow rate of 60 sccm and argon gas at a flow rate of 140 sccm are used. Subsequently, the oxide semiconductor film is processed into the desired shape to form an island-shaped oxide semiconductor film 3 Form 28. A wet etching apparatus is used to form the oxide semiconductor film.

[0481] Next, a conductive film is formed on the insulating film 318 and the oxide semiconductor film 328, and the conductive film is desired By processing it into this shape, conductive films 322a and 322b are formed. Then, insulating film 318 , oxide semiconductor film 328, and insulating films 324, 326 on conductive films 322a, 322b This is achieved (see Figures 40(A) and 40(B)).

[0482] In this embodiment, conductive films 322a and 322b are tungsten films with a thickness of 50 nm. Then, a 100nm thick aluminum film and a 50nm thick titanium film are stacked in sequence. The layer film is deposited by sputtering.

[0483] Furthermore, after the formation of the conductive films 322a and 322b, the surface of the oxide semiconductor film 328 (back chip) The channel side may be cleaned. For example, the cleaning method may involve using an aqueous phosphoric acid solution. One example is cleaning using a can. This removes the deposits adhering to the surface of the oxide semiconductor film 328. Impurities (for example, elements contained in conductive films 322a and 322b) can be removed. However, this cleaning is not always necessary, and in some cases, it may not be required. .

[0484] Furthermore, either the step of forming conductive films 322a and 322b, or the cleaning step described above, In both cases, the region exposed from the conductive films 322a and 322b of the oxide semiconductor film 328. However, it may become thinner.

[0485] In this embodiment, a silicon oxide nitride film with a thickness of 20 nm is used as the insulating film 324. A silicon oxidizride film with a thickness of 200 nm, designated as 326, was shaped using the PECVD method. To accomplish.

[0486] Furthermore, after forming the insulating film 324, the insulating film 326 is formed continuously without exposure to the atmosphere. It is preferable to do so. After forming the insulating film 324, do not open it to the atmosphere, and control the flow rate, pressure, and high of the raw material gas. By adjusting the frequency power and substrate temperature to one or more units, the insulating film 326 is formed continuously, The concentration of impurities originating from atmospheric components at the interface between the edge film 324 and the insulating film 326 is reduced. In addition, oxygen contained in the insulating films 324 and 326 is transferred to the oxide semiconductor film 328. This makes it possible to reduce the amount of oxygen vacancies in the oxide semiconductor film 328. .

[0487] In this embodiment, the insulating film 324 is set to a temperature of 220°C for holding the substrate 302. The raw materials are silane at a flow rate of 50 sccm and nitrous oxide at a flow rate of 2000 sccm. The pressure inside the processing chamber is set to 20 Pa, and the high-frequency power supplied to the parallel plate electrodes is 13.56 MHz. Hz, 100W (power density is 1.6 × 10⁻⁶) -2 W / cm 2 The PECVD method is used as follows: A silicon oxide nitride film is formed using this method.

[0488] As the insulating film 326, the substrate placed in the vacuum-evacuated processing chamber of the PECVD apparatus Maintain the temperature between 180°C and 350°C, introduce the raw material gas into the processing chamber, and adjust the pressure within the processing chamber. The pressure is set to 100 Pa or more and 250 Pa or less, more preferably 100 Pa or more and 200 Pa or less. , 0.17 W / cm² is applied to the electrode installed in the processing chamber. 2 More than 0.5W / cm 2 Below, further good The current level is 0.25 W / cm².2 More than 0.35W / cm 2 The following conditions apply to supplying high-frequency power: This then forms a silicon oxide film or a silicon oxide-nitride film.

[0489] As for the film deposition conditions for insulating film 326, the above pressure is used in the reaction chamber and the above power density is used for high-frequency current By supplying power, the decomposition efficiency of the raw material gas in the plasma increases, and the amount of oxygen radicals increases. As the oxidation of the raw material gas progresses, the oxygen content in the insulating film 326 becomes greater than the stoichiometric composition. The number also increases. On the other hand, in films formed at the above temperature, the bonding force between silicon and oxygen Because the bond is weak, some of the oxygen in the film is removed by the subsequent heat treatment. As a result, stoichiometric An oxide containing more oxygen than the theoretically required oxygen composition, with some of the oxygen being removed upon heating. An insulating film can be formed.

[0490] Furthermore, in the process of forming the insulating film 326, the insulating film 324 protects the oxide semiconductor film 328. It forms a film. Therefore, while reducing damage to the oxide semiconductor film 328, the power density is The insulating film 326 can be formed using high-frequency power.

[0491] Furthermore, in the film deposition conditions for insulating film 326, silicon-containing deposition gas against oxidizing gas By increasing the flow rate of the material, it is possible to reduce the amount of defects in the insulating film 326. ESR measurement revealed that g=2.001 originates from the dangling bond of silicon. The spin density of the signal is 6 × 10 17 spins / cm 3 Less than 3 × 10 17 spins / cm 3 The following is preferably 1.5 × 10 17 spins / cm 3 The following is missing It is possible to form an oxide insulating film with fewer depressions. As a result, the signal of transistor Tr2 It can enhance reliability.

[0492] Furthermore, after forming the insulating films 324 and 326, a heat treatment (hereinafter referred to as the first heat treatment) is performed. It is preferable to perform the following: The first heat treatment removes nitrogen acid contained in the insulating films 324 and 326. The amount of oxidized material can be reduced. Alternatively, by the first heat treatment, the insulating films 324 and 326 can be reduced. Some of the oxygen contained in the oxide semiconductor film 328 is transferred to the oxide semiconductor film 328. This can reduce the amount of oxygen deficiency.

[0493] The temperature of the first heat treatment is typically less than 400°C, preferably less than 375°C, and Preferably, the temperature is 150°C to 350°C. The first heat treatment involves nitrogen, oxygen, and superdry Dry air (water content of 20 ppm or less, preferably 1 ppm or less, preferably 10 ppb) The procedure can be carried out under the atmosphere of air or a noble gas (argon, helium, etc.). Preferably, the above nitrogen, oxygen, ultra-dry air, or noble gas does not contain hydrogen, water, etc. For heat treatment, electric furnaces, RTA (Rapid Thermal Annealing), etc. are used. It is possible.

[0494] Next, openings 382 reaching the conductive film 322a are formed in desired regions of the insulating films 324 and 326. This is done. Subsequently, a conductive film 330 is formed on the insulating film 326 and the conductive film 322a (Figure 41). (See (A) and (B)).

[0495] The opening 382 is formed using either a dry etching apparatus or a wet etching apparatus. Furthermore, the conductive film 330 is an oxide (I) having indium, tin, and silicon. (Also called TSO) Target (In2O3:SnO2:SiO2=85:10:5 [weight) Using [%]), an ITSO film with a thickness of 100 nm is formed, and then it is processed into island shapes.

[0496] By following the above steps, transistor Tr2 can be fabricated.

[0497] Next, an insulating film 326, an insulating film 334 which will be an insulating film on the conductive film 330, and an insulating film 336 A laminated film is formed with an insulating film. Subsequently, the conductive film 330 reaches a desired region of the laminated film. This forms an opening 384 (see Figures 42(A) and 42(B)).

[0498] As the insulating film 334, a silicon oxide nitride film with a thickness of 200 nm was used by the PECVD method. The insulating film 336 is a photosensitive acrylic resin with a thickness of 1.5 μm. It forms a film.

[0499] The opening 384 is formed using a dry etching apparatus or a wet etching apparatus. ru.

[0500] Next, a conductive film is formed on the insulating film 336 and the conductive film 330, and the conductive film is processed into an island shape. This process forms a conductive film 338 (see Figures 43(A) and 43(B)).

[0501] In this embodiment, the conductive film 338 is an ITSO film with a thickness of 10 nm and a film with a thickness of 200 A reflective metal film of nm (here, a metal film having silver, palladium, and copper), and a thickness of 1 A laminated film with a 0 nm ITSO film is used. In addition, wet etching is used for processing the conductive film 338. A checking device is used.

[0502] Next, island-shaped insulating films 340 are formed on the insulating film 336 and the conductive film 338 (Figure 44(A )(see B)).

[0503] As the insulating film 340, a photosensitive polyimide-based resin film with a thickness of 1.5 μm is used.

[0504] Next, an EL layer 342 is formed on the conductive film 338, and then the insulating film 340 and the EL layer 34 By forming a conductive film 344 on 2, a light-emitting element 360 is formed (Figure 45(A)(B)). reference).

[0505] The method for forming the light-emitting element 360 will be described in detail in Embodiment 5.

[0506] By following the above steps, the semiconductor device 300 shown in Figures 30(A) and 30(B) can be formed.

[0507] The configuration and methods shown in this embodiment can be appropriately combined with the configurations and methods shown in other embodiments. They can be used together.

[0508] (Embodiment 4) In this embodiment, a semiconductor device and a method for manufacturing a semiconductor device according to one aspect of the present invention are described below. This will be explained with reference to Figures 46 to 53.

[0509] <4-1. Example of Semiconductor Device Configuration 1> Figure 46(A) is a top view of a semiconductor device 400 according to one embodiment of the present invention, and Figure 46(B) is This corresponds to the cross-sectional view of the section between the dashed line A1 and A2 shown in Figure 46(A). Figure 46(B) shows a cross-section of transistor Tr1 in the direction of the channel length (L), and the transistor Includes a cross-section of Tr2 in the direction of the channel length (L).

[0510] The semiconductor device 400 shown in Figures 46(A) and 46(B) includes transistor Tr1 and transistor It has transistor Tr1 and transistor Tr2, which overlap at least a portion of each other. Both transistor Tr1 and transistor Tr2 are top-gate transistors. ru.

[0511] The region in which transistors Tr1 and Tr2 overlap at least partially is By incorporating this feature, the area required for transistor placement can be reduced.

[0512] Transistor Tr1 consists of an insulating film 306 on substrate 302 and an oxide semiconductor on insulating film 306. Body film 308, insulating film 310 on oxide semiconductor film 308, and conductive film 32 on insulating film 310 0, and an insulating film 306, an oxide semiconductor film 308, and an insulating film 314 on a conductive film 320. Furthermore, similar to Embodiment 3, the oxide semiconductor film 308 overlaps with the conductive film 320, and A channel region 308i in contact with the insulating film 310 and a source region 308 in contact with the insulating film 314 It has a drain region 308d that is in contact with the insulating film 314.

[0513] Furthermore, transistor Tr1 has an insulating film 316 on the insulating film 314, and insulating film 314 and an insulating film. The oxide semiconductor film 308 is electrically connected through the opening 341a provided on the edge film 316. The conductive film 312a is connected to the opening 341b provided in the insulating film 314 and insulating film 316. A conductive film 312b is electrically connected to the oxide semiconductor film 308 via a dielectric film 316 It comprises a conductive film 312a and an insulating film 318 on the conductive film 312b.

[0514] Furthermore, transistor Tr2 has a conductive film 312b and an insulating film 318 on the conductive film 312b. , an oxide semiconductor film 408 on the insulating film 318, and an insulating film 410b on the oxide semiconductor film 408 And, the conductive film 412b on the insulating film 410b, and the oxide semiconductor film 408 and conductive film 412b It has an insulating film 414. Also, similar to the oxide semiconductor film 308, the oxide semiconductor film 40 8 is a channel region 408i that overlaps with the conductive film 412b and is in contact with the insulating film 410b, Source region 408s in contact with insulating film 414, and drain region 408 in contact with insulating film 414 It has d and .

[0515] Furthermore, transistor Tr2 is provided with an insulating film 416 on the insulating film 414 and on the insulating film 416 A conductive film 418a is electrically connected to the oxide semiconductor film 408, and an insulating film 416 is also connected to the dielectric film 416. It has a conductive film 418b provided therein and electrically connected to the oxide semiconductor film 408.

[0516] As shown in Figures 46(A) and 46(B), the oxide semiconductor film 308 and the oxide semiconductor film 4 08 has overlapping regions.

[0517] The oxide semiconductor film 308 can be the same as the configuration shown in Embodiment 3. The oxide semiconductor film 408 has the same configuration as the oxide semiconductor film 328 shown in Embodiment 3. It can be done this way.

[0518] Therefore, either or both of transistors Tr1 and Tr2 The field effect mobility is 10 cm. 2 More preferably, transistor Tr1 and The field-effect mobility of either or both of transistors Tr2 is 30 cm 2 / Vs exceeds It becomes possible to do so.

[0519] For example, a transistor with high field-effect mobility, as described above, can be used to signal the gate signal of a display device. By using it in the gate driver that is generated, a display device with a narrow bezel (also called a narrow-bezel display) is provided. It can be used. Furthermore, the above-mentioned transistor with high field-effect mobility can be used in a display device. The source driver that supplies signals from the signal line (especially the source driver has By using it in a demultiplexer connected to the output terminal of a sub-register, it can be connected to a display device. A display device with a small number of connected wires can be provided. Also, the above field effect mobility Transistors with high performance are used for the selection transistors and drive transistors of the pixel circuits in the display device. To provide a display device with high display quality by using either or both of the sts. It is possible.

[0520] Furthermore, the semiconductor device 400 shown in Figures 46(A) and 46(B) is suitably used in the pixel circuit of a display device. This allows for the arrangement shown in Figures 46(A) and 46(B), which improves the pixel density of the display device. It becomes possible to increase the degree. For example, if the pixel density of the display device exceeds 1000 ppi, Alternatively, even if the pixel density of the display device exceeds 2000 ppi, Figure 46(A)(B By arranging the pixels as shown in the diagram, the aperture ratio can be increased.

[0521] Furthermore, when applying the semiconductor device 400 shown in Figures 46(A) and 46(B) to the pixel circuit of a display device... In this case, a configuration similar to the pixel circuit shown in Figure 31 can be used.

[0522] Furthermore, when the semiconductor device 400 shown in Figures 46(A) and 46(B) is applied to the pixels of a display device, For example, the channel length (L) and channel width (W) of a transistor, or the transistor The wiring and electrode widths connected to the transistor can be made relatively large. Compared to the case where transistors Tr1 and Tr2 are placed on the same plane, Figure 46(A As shown in (B), at least a portion of transistor Tr1 and transistor Tr2 By overlapping the pieces, the line width and other dimensions can be increased, thus reducing variations in processing dimensions. It becomes possible to reduce this.

[0523] Furthermore, in transistor Tr1 and transistor Tr2, either the conductive film or the insulating film is used. Since one or both can be used in common, the number of masks or the number of processes can be reduced. It is possible.

[0524] For example, in transistor Tr1, the conductive film 320 functions as a gate electrode, and The film 312a functions as the source electrode, and the conductive film 312b functions as the drain electrode. Furthermore, in transistor Tr1, the insulating film 310 functions as a gate insulating film. In transistor Tr2, the conductive film 312b functions as the first gate electrode, and Film 418a functions as the source electrode, and conductive film 418b functions as the drain electrode. The film 412b functions as a second gate electrode. Also, in transistor Tr2, Insulating film 318 functions as the first gate insulating film, and insulating film 410b is the second gate insulating film. It functions as such.

[0525] In this specification, the insulating film 410b may be referred to as the fourth insulating film.

[0526] Furthermore, an insulating film 336 is provided on the insulating film 416 and the conductive films 418a and 418b. Furthermore, the insulating film 336 is provided with an opening 386 that reaches the conductive film 418b. A conductive film 338 is provided on the insulating film 336. The conductive film 338 is located at the opening 38 It is connected to the conductive film 418a via 6.

[0527] Furthermore, an insulating film 340, an EL layer 342, and a conductive film 344 are provided on the conductive film 338. Furthermore, the conductive film 338, the EL layer 342, and the conductive film 344 form the light-emitting element 36 0 is formed.

[0528] Also, although not shown in the drawings, transistor Tr1 and shown in Figure 46(A)(B) The transistor Tr2 may also be an S-channel structure as described in Embodiment 3.

[0529] Furthermore, the semiconductor device 400 shown in this embodiment has transistors Tr1 and trans Tr2 and transistors Tr1 and Tr2 of the semiconductor device 300 shown in Embodiment 3 It can be used in combination with the Rangista Tr2.

[0530] As described above, a semiconductor device according to one aspect of the present invention has a stacked structure of multiple transistors, To reduce the footprint of the transistor. Also, in multiple transistors, the insulating film and By using one or both of the conductive films in common, the number of masks or process steps can be reduced. It can be reduced.

[0531] <4-2. Components of Semiconductor Devices> Next, the components included in the semiconductor device of this embodiment will be described in detail.

[0532] [Conductive film] The conductive films 412b, 418a, and 418b are the conductive films described in Embodiment 3 (conductive films 312a, conductive film 312b, conductive film 322a, conductive film 322b, conductive film 320, conductive film 3 Materials for conductive films 30, 338, and 344 can be used. In particular, conductive film 4 If an oxide conductor (OC) is used for 12b, oxygen can be added to the insulating film 410b. It is suitable.

[0533] [Insulated film] The insulating films 414, 416, and 410b are the insulating films described in Embodiment 3 (insulating film 30 6. Insulating film 314, insulating film 316, insulating film 318, insulating film 324, insulating film 326, insulating film Materials for 334, insulating film 336, and insulating film 340 can be used.

[0534] Furthermore, since the insulating film 318 is in contact with the oxide semiconductor film 408, an oxide insulating film is preferred. Insulator 410 b is preferably an oxide insulating film, and contains an excess of oxygen in a stoichiometric composition. It is more preferable to have a region (excess oxygen region). As for the insulating film 410b, acid A silicon oxide film or a silicon oxidizride film is preferable.

[0535] Furthermore, the insulating film 414 contains either hydrogen or nitrogen, or both. The edge film 414 contains nitrogen and silicon. The insulating film 414 also contains oxygen, hydrogen, water, and It has the ability to block metallic metals, alkaline earth metals, etc. Oxide semiconductor film 4 When 08 comes into contact with the insulating film 414, either the hydrogen or nitrogen in the insulating film 414 is absorbed. Alternatively, both enter the oxide semiconductor film 408, and the carrier density of the oxide semiconductor film 408 This can be made higher. Therefore, when the oxide semiconductor film 408 and the insulating film 414 are in contact The region within the oxide semiconductor film 408 functions as either a source region or a drain region.

[0536] [Oxide semiconductor film] The oxide semiconductor film 408 is the oxide semiconductor film described in Embodiment 3 (oxide semiconductor Materials for film 308 and oxide semiconductor film 328 can be used.

[0537] <4-3. Method for Manufacturing Semiconductor Devices> Next, a method for manufacturing a semiconductor device 400 according to one aspect of the present invention will be described using Figures 47 to 53. I will explain.

[0538] Note that Figures 47(A), 48(A), 49(A), 50(A), 51(A), and Figure Figures 52(A) and 53(A) are top views illustrating the method for manufacturing the semiconductor device 400. Figures 47(B), 48(B), 49(B), 50(B), 51(B), 52( Figure B) and Figure 53(B) are cross-sectional views illustrating a method for manufacturing the semiconductor device 400.

[0539] The method for fabricating transistor Tr1 is the method described in Embodiment 3. Therefore, an insulating film 306, an oxide semiconductor film 308, and an insulating film 3 can be made on the substrate 302. 10, conductive film 320, insulating film 314, insulating film 316, conductive film 312a, conductive film 312b, For the method of forming the insulating film 318, please refer to Embodiment 3 and Figures 36 to 38. stomach.

[0540] Next, an insulating film 318 is formed on the insulating film 316 and the conductive films 312a and 312b. The insulating film 318 can be formed in the same manner as in Embodiment 3.

[0541] Next, an oxide semiconductor film 408 is formed on the insulating film 318 (see Figures 47(A) and 47(B)). .

[0542] In this embodiment, an In-Ga-Zn metal oxide target (In:Ga:Zn=4: Using a 2:4.1 (atomic ratio), an oxide semiconductor film is formed by sputtering. Furthermore, the substrate temperature during the formation of the oxide semiconductor film was set to 170°C, and the film formation gas used during the formation was set to For this purpose, oxygen gas at a flow rate of 60 sccm and argon gas at a flow rate of 140 sccm are used. Subsequently, the oxide semiconductor film is processed into the desired shape to form island-shaped oxide semiconductor films 4 Form O8. A wet etching apparatus is used to form the oxide semiconductor film.

[0543] Next, a laminated film of the insulating film and the conductive film is formed on the insulating film 318 and the oxide semiconductor film 408. Then, by processing the laminated film into the desired shape, island-shaped insulating film 410b and island A conductive film 412b is formed (see Figures 48(A) and 48(B)).

[0544] Subsequently, insulating film 414 is placed on insulating film 318, oxide semiconductor film 408, and conductive film 412b. , 416 is formed. Furthermore, by forming the insulating film 414, the oxide in contact with the insulating film 414 The semiconductor film 408 forms the source region 408s and the drain region 408d. The oxide semiconductor film 408 that does not come into contact with film 414, in other words, the oxide semiconductor film that comes into contact with insulating film 410b The conductive film 408 becomes the channel region 408i. As a result, the channel region 408i, An oxide semiconductor film 408 having a drain region 408s and a drain region 408d is formed. (See Figures 49(A) and 49(B)).

[0545] In this embodiment, the insulating film 410b is a silicon oxidizride film with a thickness of 50 nm. It is formed using a PECVD apparatus. In addition, the conductive film 412b is an acid with a thickness of 200 nm. An oxide semiconductor film is formed using a sputtering apparatus. Therefore, the same composition as the oxide semiconductor film 408 is used. Also, as the insulating film 414, a thickness of 1 A silicon nitride film of 00 nm is formed using a PECVD apparatus. In addition, insulating film 416 and Next, a silicon oxide-nitride film with a thickness of 200 nm is formed using a PECVD apparatus.

[0546] By using a silicon nitride film as the insulating film 414, the conductive film 4 in contact with the insulating film 414 12b, source region 408s, and drain region 408d contain hydrogen in the silicon nitride film and Nitrogen enters either or both of the conductive film 412b, source region 408s, and The carrier density in the drain region 408d can be increased. Therefore, the oxide semiconductor film A portion of area 408 and the conductive film 412b become an oxide conductor (OC).

[0547] The insulating film 410b is formed self-aligned using the conductive film 412b as a mask.

[0548] Next, openings 48 that reach the oxide semiconductor film 408 in the desired regions of the insulating films 414 and 416 Forms 2a and 482b (see Figure 49(A)(B)).

[0549] The openings 482a and 482b are formed using a dry etching apparatus or a wet etching apparatus. Use a device.

[0550] Next, the insulating film 416 and the oxide semiconductor film 40 are placed to cover the openings 482a and 482b. A conductive film is formed on 8, and the conductive film is processed into island shapes, thereby forming conductive films 418a, 418b It forms (see Figures 49(A) and 49(B)).

[0551] Conductive films 418a and 418b consist of a tungsten film with a thickness of 100 nm and a film with a thickness of 200 nm. A copper film of thickness m is formed by sputtering.

[0552] By following the above steps, transistor Tr2 can be fabricated.

[0553] Next, an insulating film 336 is formed on the insulating film 416 and the conductive films 418a and 418b. Subsequently, by processing a desired region of the insulating film 336, an opening 386 is formed that reaches the conductive film 418a. It forms (see Figures 50(A) and 50(B)).

[0554] In this embodiment, the insulating film 336 is a photosensitive acrylic resin with a thickness of 1.5 μm. It forms a film.

[0555] Next, a conductive film is formed on the insulating film 336 and the conductive film 418a, and the conductive film is processed into an island shape. This forms a conductive film 338 (see Figures 51(A) and 51(B)).

[0556] In this embodiment, the conductive film 338 is an ITSO film with a thickness of 10 nm and a film with a thickness of 200 A reflective metal film of nm (here, a metal film having silver, palladium, and copper), and a thickness of 1 A laminated film with a 0 nm ITSO film is used. In addition, wet etching is used for processing the conductive film 338. A checking device is used.

[0557] Next, island-shaped insulating films 340 are formed on the insulating film 336 and the conductive film 338 (Figure 52(A )(see B)).

[0558] As the insulating film 340, a photosensitive polyimide-based resin film with a thickness of 1.5 μm is used.

[0559] Next, an EL layer 342 is formed on the conductive film 338, and then the insulating film 340 and the EL layer 34 By forming a conductive film 344 on 2, a light-emitting element 360 is formed (Figure 53(A)(B)). reference).

[0560] The method for forming the light-emitting element 360 will be described in detail in Embodiment 5.

[0561] By following the above steps, the semiconductor device 400 shown in Figures 46(A) and 46(B) can be manufactured.

[0562] The configuration and methods shown in this embodiment can be appropriately combined with the configurations and methods shown in other embodiments. They can be used together.

[0563] (Embodiment 5) In this embodiment, regarding a light-emitting element that can be used in a semiconductor device according to one aspect of the present invention, This will be explained using Figures 54 to 56.

[0564] <5-1. Example of light-emitting element configuration> First, regarding the configuration of a light-emitting element that can be used in a semiconductor device according to one aspect of the present invention, Figure Let's explain using Figure 54. Figure 54 is a schematic cross-sectional view of the light-emitting element 160.

[0565] The light-emitting element 160 may be made of either an inorganic compound or an organic compound, or both. It can be used. As for the organic compound used in the light-emitting element 160, a low molecular weight compound and Examples include polymer compounds. Polymer compounds are thermally stable and can be easily uniformly applied by coating methods, etc. It is suitable because it can form a thin film with excellent uniformity.

[0566] The light-emitting element 160 shown in Figure 54 has a pair of electrodes (conductive film 138 and conductive film 144) The device has an EL layer 142 provided between the pair of electrodes. The EL layer 142 emits at least light. It has 150 layers.

[0567] Furthermore, the EL layer 142 shown in Figure 54 includes, in addition to the light-emitting layer 150, a hole injection layer 151 and a hole channel It has functional layers such as a transport layer 152, an electron transport layer 153, and an electron injection layer 154.

[0568] In this embodiment, of the pair of electrodes, the conductive film 138 is used as the anode, and the conductive Although film 144 is described as the cathode, this is not the only configuration of the light-emitting element 160. In other words, conductive film 138 is used as the cathode, conductive film 144 as the anode, and the stacking of each layer between these electrodes is Alternatively, the order can be reversed. That is, from the anode side, the hole injection layer 151 and the hole transport layer 15 The order in which layers 2, the light-emitting layer 150, the electron transport layer 153, and the electron injection layer 154 are stacked is as follows: That's all you need to do.

[0569] Note that the configuration of the EL layer 142 is not limited to the configuration shown in Figure 54, and in addition to the light-emitting layer 150, Among the hole injection layer 151, the hole transport layer 152, the electron transport layer 153, and the electron injection layer 154 The configuration should have at least one selected from the above. Alternatively, the EL layer 142 is a hole Or reduce the electron injection barrier, improve hole or electron transport, hole or electron It has functions such as inhibiting transportability or suppressing the quenching phenomenon caused by electrodes. The configuration may have functional layers. Note that even if each functional layer is a single layer, multiple functional layers may be used. It may also have a layered configuration.

[0570] Low molecular weight compounds and high molecular weight compounds can be used in the light-emitting layer 150.

[0571] In this specification, a polymer compound is defined as having a molecular weight distribution and an average molecular weight of 1 ×10 3 〜1×10 8It is a polymer. Furthermore, a low molecular weight compound is defined as having an average molecular weight of... 1 x 10 4 The following compounds are involved.

[0572] Furthermore, polymer compounds are compounds in which one or more constituent units are polymerized. In other words, the constituent unit refers to one or more units that a polymer compound has.

[0573] Furthermore, polymer compounds include block copolymers, random copolymers, alternating copolymers, and graph copolymers. It may be any of the copolymers, or other embodiments.

[0574] When the terminal groups of a polymer compound have polymerization-active groups, the light-emitting properties or brightness in the light-emitting element may be affected. This can lead to a decrease in lifespan. Therefore, the end groups of polymer compounds are stable. It is preferable that the group is a terminal group. The stable terminal group is preferably a group covalently bonded to the main chain. Preferably, the group is bonded to an aryl group or a heterocyclic group via a carbon-carbon bond.

[0575] When a low molecular weight compound is used in the light-emitting layer 150, the low molecular weight compound that functions as the host material In addition, it is preferable to have a luminescent low-molecular-weight compound as a guest material in the luminescent layer 150. This means that the host material is present in a greater proportion by weight than the guest material, and the guest material is host It is dispersed in the material.

[0576] As the guest material, any luminescent organic compound may be used, and the luminescent organic compound is In this case, a substance that can emit fluorescence (hereinafter also called a fluorescent compound) or a substance that emits phosphorescence A substance capable of this (hereinafter also referred to as a phosphorescent compound) can be used.

[0577] In one embodiment of the present invention, the light-emitting element 160 comprises a pair of electrodes (conductive film 138 and conductive film 1 44) By applying a voltage between them, electrons are released from the cathode and holes from the anode. Each is injected into the EL layer 142, and current flows. Then, the injected electrons and holes recombine. By combining, excitons are formed. This is due to the recombination of carriers (electrons and holes). Of the excitons produced, the ratio of singlet excitons to triplet excitons (hereinafter referred to as the exciton generation probability) is: Statistically, the ratio is 1:3. Therefore, in a light-emitting device using a fluorescent compound, The proportion of singlet excitons that contribute to luminescence is 25%, while triplet excitons that do not contribute to luminescence are generated. The rate of riser generation is 75%. On the other hand, in light-emitting devices using phosphorescent compounds, Both singlet and triplet excitons can contribute to luminescence. Therefore, fluorescence Light-emitting devices using phosphorescent compounds have higher luminescence efficiency than light-emitting devices using phosphorescent compounds. It is preferable to become that way.

[0578] An exciton is a carrier (electron and hole) pair. An exciton has energy. Therefore, the material from which excitons are generated enters an excited state.

[0579] When a polymer compound is used in the light-emitting layer 150, the polymer compound has holes as its constituent units. A framework that has the function of transporting holes (hole transport) and a framework that has the function of transporting electrons (electron transport) It is preferable to have a skeleton that is π electron-rich complex aromatic skeleton or aromatic A It is preferable that it has at least one mine skeleton and a π-electron-deficient heteroaromatic skeleton. These skeletons are connected directly or via other skeletons.

[0580] Furthermore, polymer compounds have a backbone that has hole-transporting properties and a backbone that has electron-transporting properties. In this case, it becomes possible to easily control your career balance. The binding region can also be easily controlled. To achieve this, a framework with hole transport properties and The ratio of the electron-transporting framework to the other components is preferably in the range of 1:9 to 9:1 (molar ratio). Furthermore, the proportion of the electron-transporting skeleton is higher than that of the hole-transporting skeleton. Even better.

[0581] Furthermore, polymer compounds have a hole-transporting skeleton and electron-transporting properties as constituent units. In addition to its existing skeleton, it may also have a luminescent skeleton. A polymer compound having a luminescent skeleton In this case, it is preferable that the proportion of the luminescent skeleton to the total constituent units of the polymer compound is low. Specifically, preferably 0.1 mol% or more and 10 mol% or less, and more preferably The concentration is between 0.1 mol% and 5 mol%.

[0582] Furthermore, the polymer compound used in the light-emitting element 160 has a specific bonding direction, bonding angle, and bonding of each constituent unit. Lengths and other properties may differ. Furthermore, each constituent unit may have different substituents. The structures may have different skeletons between them. Also, the polymerization method of each constituent unit may be different. stomach.

[0583] Furthermore, the light-emitting layer 150, in addition to the polymer compound that functions as the host material, also contains a low-luminescence material. Molecular compounds may be used as guest materials. In this case, the high-molecular-weight compound that functions as the host material A luminescent low-molecular-weight compound is dispersed in the subsidiary compound as a guest material, and the polymer compound is It is present in a greater weight ratio than at least luminescent low-molecular-weight compounds. The amount is preferably 0.1 wt% to 10 wt% by weight relative to the polymer compound. Yes, and more preferably 0.1 wt% to 5 wt%.

[0584] Next, the details of the components of a light-emitting element according to one aspect of the present invention will be described below.

[0585] [Luminous layer] The materials that can be used for the light-emitting layer 150 are described below.

[0586] There are no particular limitations on the polymer compounds that can be used in the light-emitting layer 150, but complex aromatic compounds are also available. It is preferable that it has at least one of a fragrance skeleton and an aromatic hydrocarbon skeleton. Structures in which the skeletons are bonded to each other directly or via arylene or alkylene groups Preferred. The groups bonded via the above skeleton include arylene groups and alkylene groups. It is not limited to the n-type.

[0587] Furthermore, among the heteroaromatic skeletons possessed by polymer compounds, the furan skeleton, the thiophene skeleton, and The pyrrole skeleton is stable and reliable, so one of the skeletons selected from among them It is preferable to have one or more. Also, pyridine skeleton, diazine skeleton (pyrazine skeleton Pyrimidine skeleton and pyridazine skeleton, and triazine skeleton are preferred, among others Agin and triazine skeletons are preferred because they are stable and reliable. Also, for example, furan skeleton, benzofuran skeleton, dibenzofuran skeleton, benzodifuran skeleton, thiophene n skeleton, benzothiophene skeleton, dibenzothiophene skeleton, benzodithiophene skeleton, ch Enothiophene skeleton, dithienoshiofen skeleton, dithienofurne skeleton, dithienoselenof phenyl skeleton, cyclopentadithiophene skeleton, dithienosylol skeleton, thienopyrrole skeleton Dithienopyrrole skeleton, thienoindole skeleton, thienopyridine skeleton, thienopyrazine Skeleton, thiazole skeleton, thiadiazole skeleton, benzothiazole skeleton, benzodithiazole oxazole skeleton, oxazole skeleton, oxadiazole skeleton, benzoxazole skeleton, benzodi Oxazole skeleton, selenophen skeleton, benzoselenophen skeleton, dibenzoselenophen Skeleton, benzodiserenofen skeleton, selenoselenofen skeleton, indasenothiophene skeleton Indasenodithiophene skeleton, indasenoselenophene skeleton, indasenodiselenophene Indole skeleton, pyrrole skeleton, indole skeleton, carbazole skeleton, indolocarbazole skeleton Bicarbazole skeleton, pyrrolopyrrole skeleton, acridan skeleton, acridone skeleton, fe Noxazine skeleton, phenothiazine skeleton, phenazine skeleton, phenazacillin skeleton, azepine Skeletons, such as the juroridine skeleton, can be used. Also, for example, quinoline skeletons, naphthium Lysine skeleton, quinoxaline skeleton, quinazoline skeleton, phthalazine skeleton, cinnoline skeleton, p Theridine skeleton, acridine skeleton, phenanthoridine skeleton, phenanthroline skeleton, benzo Quinoline skeleton, benzoquinoxaline skeleton, benzoquinazoline skeleton, dibenzoquinoline skeleton Dibenzoquinoxaline skeleton, dibenzoquinazoline skeleton, imidazole skeleton, pyrazole skeleton, triazole skeleton, benzimidazole skeleton, imidazopyridine skeleton, purine skeleton Using triazolopyrimidine skeleton, triazolopyridine skeleton, indazole skeleton, etc. It is possible.

[0588] Furthermore, an aromatic hydrocarbon skeleton may be used instead of the above-mentioned heteroaromatic skeleton. Aromatic carbon Examples of hydrogenated skeletons include biphenyl skeletons, naphthalene skeletons, anthracene skeletons, and Lysene skeleton, phenanthrene skeleton, triphenylene skeleton, fluorene skeleton, spirofluorene Examples include the len skeleton, indacene skeleton, and dibenzosilol skeleton.

[0589] Furthermore, aromatic amine skeletons can be used in polymer compounds, and among them, secondary amine skeletons... A tertiary amine skeleton is preferred, and a triarylamine skeleton is particularly preferred. The aryl group of the amine skeleton can be a substituted or unsubstituted group with 6 to 13 carbon atoms forming the ring. The aryl group is preferred, and examples include the phenyl group, naphthyl group, fluorenyl group, etc. For example, triphenylamine skeleton, phenylenediamine skeleton, naphthalenediamine skeleton, Examples include the ngidine skeleton.

[0590] Other skeletons that can be used in polymer compounds include ketone skeletons and alkoxy skeletons. Examples include the skeleton, etc.

[0591] Furthermore, the above aromatic amine skeleton, heteroaromatic skeleton, and aromatic hydrocarbon skeleton are all When bonded with a ylene group or alkylene group, the arylene group and alkylene group are as follows: For example, phenylene group, biphenyldiyl group, terphenyldiyl group, naphthalene group yl group, fluoroorangeyl group, anthracenediyl group, 9,10-dihydroanthracenediyl Iyl group, phenanthrendyl group, pyrendhryl group, perylenediyl group, chrysendiyl Group, alkoxyphenylene group, arylenevinylene group (phenylenevinylene group, etc.), vinyl Examples include ylene groups. Furthermore, ether bonds, thioether bonds, ester bonds, etc. You can combine them like this.

[0592] The aromatic amine skeleton, heteroaromatic skeleton, and aromatic hydrocarbon skeleton described above, or the above The arylene group and alkylene group may each have substituents. For example, an alkyl group, alkoxy group, or alkylthio group having 1 to 20 carbon atoms, A cycloalkyl group having 3 to 20 carbon atoms, or a substitution with 6 to 18 carbon atoms, is also possible. or unsubstituted aryl or aryloxy groups, heterocyclic compounds having 4 to 14 carbon atoms The microbial group can also be selected as a substituent. As an alkyl group having 1 to 20 carbon atoms. Specifically, these include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group. butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, decyl group Examples include the 2-ethylhexyl group, lauryl group, 2-ethylhexyl group, and 3-methylbutyl group. Furthermore, specific examples of alkoxy groups having 1 to 20 carbon atoms include methoxy groups, ethoxy groups, and ethoxy groups. Xyl group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyl 2-ethylhexyloxy group, decyloxy group, lauryloxy group, 2-ethylhexyloxy group, 3-methyl Examples include the tyl-butoxy group and the isopropyloxy group. Also, carbon-1 groups Examples of alkylthio groups with up to 20 carbon atoms include methylthio group, ethylthio group, and butythio group. Luthio group, pentylthio group, hexylthio group, heptylthio group, octylthio group, decyl Thio group, laurylthio group, 2-ethylhexylthio group, 3-methylbutylthio group, isop Examples include the ropirthio group. Also, cycloalkyl groups with 3 to 20 carbon atoms. Specifically, the cyclopropyl group includes cyclopropyl group, cyclobutyl group, cyclopentyl group, and cyclopropyl group. Chlohexyl group, norbornyl group, noradamantyl group, adamantyl group, homoadamantine Examples include the til group and the tricyclodecanyl group. Also, groups with 6 to 1 carbon atoms. Specifically, the aryl groups of 8 include substituted or unsubstituted phenyl groups, naphthyl groups, and phenyl groups. Examples include phenyl groups, fluorenyl groups, anthracenyl groups, and pyrenyl groups. Furthermore, as aryloxy groups having 6 to 18 carbon atoms, specifically, substituted or unsubstituted groups are also included. Substituted alkoxyphenoxy group, alkylphenoxy group, naphthyloxy group, anthrace Examples include the yloxy group and the pyrenyloxy group. Also, groups with 4 to 4 carbon atoms. The 14 heterocyclic compound groups specifically include substituted or unsubstituted thienyl groups and pyrrolyl groups. Examples include a furyl group and a pyridyl group. Furthermore, the above substituents are bonded to each other. A ring may be formed. For example, the carbon at position 9 in the fluorene skeleton. When an element has two phenyl groups as substituents, the phenyl groups bond together. One example is when a spirofluorene skeleton is formed. Note that in the case of no substitution, It is advantageous in terms of ease of synthesis and the price of raw materials.

[0593] Examples of the above polymer compounds include poly[2-methoxy-5-(2-ethylhexyl [Luoxy)-1,4-phenylenevinylene] (abbreviation: MEH-PPV), poly(2,5- Polyphenylene vinylene (PPV) induction such as dioctyl-1,4-phenylene vinylene Body, poly(9,9-di-n-octylfluorenyl-2,7-diyl) (abbreviation: PF8) , poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(ben Zo[2,1,3]thiadiazole-4,8-diyl) (abbreviation: F8BT), poly[(9 ,9-di-n-octylfluorenyl-2,7-diyl)-alt-(2,2'-bitio) Fen-5,5'-Zyl) (abbreviated as F8T2), Poly[(9,9-Dioctyl-2,7 (-Divinylenefluorenylene)-alt-(9,10-Anthracene)], Poly[(9, 9-Dihexylfluorene-2,7-diyl)-alt-(2,5-dimethyl-1,4- Polyfluorene derivatives such as phenylene, poly(3-hexylthiophene-2,5-di Polyalkylthiophene (PAT) derivatives such as (P3HT), polyphenyl Examples include derivatives of 9-vinylcarbazole. In addition, these polymer compounds and poly(9-vinylcarbazole) are also used. (Abbreviation: PVK), poly(2-vinylnaphthalene), poly[bis(4-phenyl)( High molecular weight compounds such as 2,4,6-trimethylphenyl)amine (abbreviated as PTAA) are used. The light-emitting layer may be doped with a photochromic low-molecular-weight compound.

[0594] There are no particular limitations on the fluorescent compounds that can be used in the light-emitting layer 150, but ant Helical derivatives, tetracene derivatives, chrysene derivatives, phenanthrene derivatives, pyrene derivatives Body, perylene derivatives, stilbene derivatives, acridone derivatives, coumarin derivatives, phenoxy Sazine derivatives, phenothiazine derivatives, etc. are preferred. For example, substitution of the following materials is also possible. Alternatively, unsubstituted materials can be used. The above substituents can be used as substituents. It is possible. Furthermore, an aliphatic hydrocarbon group is preferred, more preferably an alkyl group, and even more preferably It is a branched alkyl group.

[0595] Specifically, 5,6-bis[4-(10-phenyl-9-antryl)phenyl]-2 ,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl -9-anthryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2) BPy), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluorine) [Len-9-yl]phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn) N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H -Fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMem FLPAPrn), N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl) )phenyl]-N,N'-bis(4-tert-butylphenyl)-pyrene-1,6-di Amine (abbreviation: 1,6tBu-FLPAPrn), N,N'-bis[4-(9-phenyl -9H-fluoren-9-yl)phenyl]-N,N'-diphenyl-3,8-dicyclo Hexylpyrene-1,6-diamine (abbreviation: ch-1,6FLPAPrn), N,N'- Bis[4-(9H-carbazole-9-yl)phenyl]-N,N'-diphenylsyl Ben-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazole-9-yl) )-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA) ), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-yl) Tolyl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4 -(10-phenyl-9-anthryl)phenyl]-9H-carbazole-3-amine( Abbreviation: PCAPA), Perylene, 2,5,8,11-Tetra(tert-butyl)perylene (Abbreviation: TBP), 4-(10-phenyl-9-antryl)-4'-(9-phenyl -9H-carbazole-3-yl)triphenylamine (abbreviation: PCBAPA), N,N ''-(2-tert-butylanthracene-9,10-diyldi-4,1-phenylene )Bis[N,N',N'-triphenyl-1,4-phenylenediamine] (abbreviation: DPA) BPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl) Phenyl]-9H-carbazole-3-amine (abbreviation: 2PCAPPA), N-[4-( 9,10-Diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl- 1,4-Phenylenediamine (abbreviation: 2DPAPPA), N,N,N',N',N'', N'',N''',N'''-Octaphenyldibenzo[g,p]chrysene-2,7,1 0,15-tetraamine (abbreviation: DBC1), coumarin 30, N-(9,10-diphenyl Lu-2-anthryl)-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-an [Tryl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCABP) hA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl Lu-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(1, [1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1 ,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(1,1'3'-3'-3' Phenyl-2-yl)-N-[4-(9H-carbazole-9-yl)phenyl]-N- Phenylanthracene-2-amine (abbreviation: 2YGABPhA), N,N,9-triphen Nylanthracene-9-amine (abbreviation: DPhAPhA), Coumarin 6, Coumarin 545 T,N,N'-diphenylquinacridone (abbreviation: DPQd), rubren, 2,8-di-t ert-butyl-5,11-bis(4-tert-butylphenyl)-6,12-dife Niltetracene (abbreviation: TBRb), Nile Red, 5,12-bis(1,1'-biphenate) Nyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2 -[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyran-4-i Lyden)propanedinitrile (abbreviation: DCM1), 2-{2-methyl-6-[2-(2, 3,6,7-Tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethen [Lu]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N, N',N'-Tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation) :p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-me (Tylphenyl)acenaphtho[1,2-a]fluorantene-3,10-diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl Tyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-i [Ethenyl-4H-pyran-4-ylidene]propanedinitrile (abbreviation: DCJTI) ), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3 ,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl ]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2 ,6-bis{2-[4-(dimethylamino)phenyl]ethenyl}-4H-pyran-4- Iridene)propanedinitrile (abbreviation: BisDCM), 2-{2,6-bis[2-(8 -Methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5 H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene} Propanedinitrile (abbreviation: BisDCJ™), 5,10,15,20-tetrapheny Rubisbenzo[5,6]indeno[1,2,3-cd:1',2',3'-lm]perile Examples include n, etc.

[0596] There are no particular limitations on the luminescent skeleton that can be used in polymer compounds, but Spiral, tetracene, chrycene, phenanthrene, pyrene, perylene, stilbene, acrylic acid From the skeleton of lidon, coumarin, phenoxazine, phenothiazine, etc., one or two It is preferable that the structure has a constituent unit in which hydrogen is removed from the aromatic ring. Also, the above The substituents listed below can be used. In addition, an aliphatic hydrocarbon group can be introduced as a substituent. It may be an alkyl group, preferably a branched alkyl group.

[0597] Phosphorescent compounds include iridium, rhodium, or platinum-based organometallic complexes, or Examples include metal complexes, particularly organoiridium complexes, such as iridium-based orthometallic complexes. The body is preferable. The ligands for orthometallation are 4H-triazole ligands and 1H- Reazole ligands, imidazole ligands, pyridine ligands, pyrimidine ligands, pyrazine Examples include ligands, or isoquinoline ligands. As for metal complexes, porphyri Examples include platinum complexes having ligands. Also, substitution or other methods of the following materials are possible. Unsubstituted materials can be used. The substituents used are those listed above. It is possible.

[0598] Examples of substances that have a blue or green emission peak include tris{2-[5-(2 -methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazo [Ir-3-yl-κN2]phenyl-κC}iridium(III) (abbreviation: Ir(mpp) tz-dmp)3), Tris(5-methyl-3,4-diphenyl-4H-1,2,4-) Ryasolato) Iridium(III) (abbreviation: Ir(Mptz)3), Tris[4-(3- [Biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato] Lydium(III) (abbreviation: Ir(iPrptz-3b)3), Tris[3-(5-Bif [Phenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazolato]iridi A 4H-triazole skeleton like Um(III) (abbreviation: Ir(iPr5btz)3) The organometallic iridium complex and tris[3-methyl-1-(2-methylphenyl)- 5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: Ir( Mptz1-mp)3), Tris(1-methyl-5-phenyl-3-propyl-1H-1 ,2,4-Triazolat) Iridium(III) (abbreviation: Ir(Prptz1-Me)3 ) Organometallic iridium complexes having a 1H-triazole skeleton, such as fac-tris [1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole] Dium(III) (abbreviation: Ir(iPrpmi)3), Tris[3-(2,6-dimethyl] Phenyl)-7-methylimidazo[1,2-f]phenantridinato]iridium(II Organic compounds having an imidazole skeleton, such as I) (abbreviation: Ir(dmpimpt-Me)3) Metallic iridium complexes and bis[2-(4',6'-difluorophenyl)pyridinate-N ,C 2’ Iridium(III) tetrakis(1-pyrazolyl) borate (abbreviation: Fir 6) Bis[2-(4',6'-difluorophenyl)pyridinate-N,C 2’ Iridi Um(III) picolinate (abbreviation: Firpic), bis{2-[3',5'-bis( Trifluoromethyl)phenyl]pyridinate-N,C 2’ Iridium(III) picoli Naat (abbreviation: Ir(CF3ppy)2(pic)), Bis[2-(4',6'-jiful Olophenyl)pyridinato-N,C 2’ Iridium(III) acetylacetonate ( A phenylpyridine derivative having an electron-withdrawing group, such as the abbreviation FIr(acac)), is coordinated. Examples of its derivatives include organometallic iridium complexes. Among those mentioned above, 4H-triazole bone Organometallic iridium complexes with a specific rating are particularly preferred because they also exhibit excellent reliability and luminescence efficiency. .

[0599] Furthermore, examples of substances that have a green or yellow emission peak include tris(4-methyl Iridium(III) (abbreviation: Ir(mppm)3), 6-phenylpyrimidinato Tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: I r(tBuppm)3), (acetylacetonate)bis(6-methyl-4-phenylpyryl) Iridium(III) (abbreviation: Ir(mppm)2(acac)), (acetyl Luacetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium III) (Abbreviation: Ir(tBuppm)2(acac)), (acetylacetonato)bis [4-(2-norbornyl)-6-phenylpyrimidinato]iridium(III) (abbreviation) :Ir(nbppm)2(acac)),(acetylacetonato)bis[5-methyl-6 -(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: Ir(mpmppm)2(acac)), (acetylacetonato)bis{4,6-dimethicone} Lu-2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN3]phenyl- κC} Iridium(III) (abbreviation: Ir(dmppm-dmp)2(acac)), ( Acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III)( Abbreviation: Organometallic irritants with a pyrimidine skeleton, such as Ir(dppm)2(acac) Dium complexes, and (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazine Iridium(III) (abbreviation: Ir(mppr-Me)2(acac)), (acetyl Luacetonato)bis(5-isopropyl-3-methyl-2-phenylpyradinato)iridi Pyrazine bones like Um(III) (abbreviation: Ir(mppr-iPr)2(acac)) iridium organometallic complexes with a specific classification, and tris(2-phenylpyridinato-N,C) 2’ ) Iridium(III) (abbreviation: Ir(ppy)3), bis(2-phenylpyridinate-N) ,C 2’ Iridium(III) acetylacetonate (abbreviation: Ir(ppy)2(ac) ac)), bis(benzo[h]quinolinate)iridium(III)acetylacetonate (Abbreviation: Ir(bzq)2(acac)), Tris(benzo[h]quinolinato)iridiu Mu(III) (abbreviation: Ir(bzq)3), Tris(2-phenylquinolinato-N,C) 2 ’ ) Iridium(III) (abbreviation: Ir(pq)3), bis(2-phenylquinolinazole- N,C 2’ Iridium(III) acetylacetonate (abbreviation: Ir(pq)2(ac) Organometallic iridium complexes having a pyridine skeleton, such as ac)), and bis(2,4-diph Enyl-1,3-oxazolato-N,C 2’ Iridium(III) Acetylaceton (abbreviation: Ir(dpo)2(acac)), bis{2-[4'-(perfluorophenicol) [Phenyl]pyridinate-N,C 2’ Iridium(III) acetylacetonate ( Abbreviation: Ir(p-PF-ph)2(acac)), bis(2-phenylbenzothiazolat -N,C 2’ Iridium(III) acetylacetonate (abbreviation: Ir(bt)2(a) In addition to organometallic iridium complexes such as CAC, there are also tris(acetylacetonate)(monophenate). Nanthroline terbium(III) (abbreviation: Tb(acac)3(Phen)) Examples include rare earth metal complexes. Among those mentioned above, organometallic ylids having a pyrimidine skeleton are particularly noteworthy. Dium complexes are particularly preferred because they offer outstanding reliability and luminous efficiency.

[0600] Furthermore, examples of substances that have a yellow or red emission peak include (diisobutyryl Methanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(II) I) (abbreviation: Ir(5mdppm)2(dibm)), bis[4,6-bis(3-methyl [Phenyl)pyrimidinato](dipivaloylmethanato)iri...

Claims

[Claim 1] A semiconductor device having a first transistor and a second transistor, The first transistor described above is The first gate electrode and The first insulating film on the first gate electrode, The first oxide semiconductor film on the first insulating film, The first source electrode on the first oxide semiconductor film, The first drain electrode on the first oxide semiconductor film, The first oxide semiconductor film, the first source electrode, and the second insulating film on the first drain electrode, The second insulating film has a second gate electrode, The second transistor described above is The first drain electrode and, The second insulating film on the first drain electrode, The second oxide semiconductor film on the second insulating film, The second source electrode on the second oxide semiconductor film, The second drain electrode on the second oxide semiconductor film, The second oxide semiconductor film, the second source electrode, and the third insulating film on the second drain electrode, The third insulating film has a third gate electrode, A semiconductor device having overlapping regions between the first oxide semiconductor film and the second oxide semiconductor film.

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