Semiconductor equipment

Abstract

To provide a semiconductor device having stable electrical characteristics. Or, to provide a semiconductor device having normally-off electrical characteristics. To provide a semiconductor device having normally-off electrical characteristics. 【Solution means】A semiconductor device having a gate electrode, a gate insulator, and an oxide semiconductor, where the oxide semiconductor has fluorine in the channel formation region, and the fluorine concentration in the channel formation region is 1×1 0 0 20 atoms / cm 3 or more and 1×10 22 atoms / cm 3 or less. Also, the addition of fluorine is performed by ion implantation. There is such a semiconductor device. Also, the addition of fluorine is performed by ion implantation.

Description

[Technical Field]

[0001] The present invention relates, for example, to transistors and semiconductor devices. Or, the present invention relates, for example, to transistors and semiconductor devices. The present invention relates to methods for fabricating transistors and semiconductor devices. Alternatively, the present invention relates to, for example, display Regarding devices, light-emitting devices, lighting devices, energy storage devices, memory devices, imaging devices, processors, and electronic equipment. To do so. Or, to manufacture display devices, liquid crystal display devices, light-emitting devices, memory devices, imaging devices, and electronic devices. This relates to manufacturing methods. Or, display devices, liquid crystal display devices, light-emitting devices, memory devices, imaging devices, electric Regarding the method of driving the sub-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. Or, the present invention. One aspect of this is a process, machine, manufacture, or composition. It concerns matter.

[0003] In this specification, a semiconductor device refers to a device that can function by utilizing semiconductor properties. This refers to a general category of devices, including display devices, light-emitting devices, lighting devices, memory devices, imaging devices, electro-optical devices, and semiconductors. Body circuits and electronic devices may include semiconductor devices. [Background technology]

[0004] The technology of constructing transistors using semiconductors on substrates with insulating surfaces is attracting attention. These transistors are widely used in semiconductor devices such as integrated circuits and display devices. Silicon is known as a semiconductor that can be applied to transistors.

[0005] The silicon used in transistor semiconductors is either amorphous silicon or polycrystalline silicon, depending on the application. The terms "recon" and "recon" are used interchangeably. For example, they are applied to transistors that make up large display devices. In such cases, it is preferable to use amorphous silicon for which film deposition technology on large-area substrates has been established. On the other hand, it is applied to transistors that constitute a high-performance display device with an integrated drive circuit. In this case, if polycrystalline silicon is used, which can be used to fabricate transistors with high field-effect mobility It is suitable. Polycrystalline silicon is suitable for amorphous silicon, which is subjected to high-temperature heat treatment or laser treatment. A method for forming it by processing is known.

[0006] In recent years, transistors using oxide semiconductors (typically In-Ga-Zn oxide) have been developed. Development is becoming more active.

[0007] The history of oxide semiconductors is long, and in 1988, crystalline In-Ga-Zn oxide was used in semiconductor devices. It has been disclosed that it can be used for (see Patent Document 1). Also, in 1995, oxide A transistor using semiconductors has been invented, and its electrical properties have been disclosed (Patent document). See reference 2. ).

[0008] Transistors using oxide semiconductors are different from transistors using amorphous silicon, and multi It has different characteristics from transistors using crystalline silicon. For example, it uses an oxide semiconductor. Display devices that utilize oxide semiconductor transistors are known to have low power consumption. Since conductors can be formed using methods such as sputtering, they can be used to construct large display devices. It can be used in transistors. Furthermore, transistors using oxide semiconductors have high electric fields. Because it has effective mobility, it is possible to realize a high-performance display device with an integrated drive circuit. It is possible to modify and utilize some of the production equipment for transistors using amorphous silicon. Therefore, it also has the advantage of reducing capital investment.

[0009] For example, in order to mass-produce semiconductor devices such as display devices, a transient using oxide semiconductors The electrical properties of the device must be stable.

[0010] In transistors using oxide semiconductors, controlling oxygen vacancies in the oxide semiconductor is extremely difficult. It is important to minimize oxygen deficiency in order to obtain stable transistor characteristics. It is preferable to do so, and one technique for this is to inject oxygen into an oxide semiconductor ( See patent document 3. ). [Prior art documents] [Patent Documents]

[0011] [Patent Document 1] Japanese Patent Application Publication No. 63-239117 [Patent Document 2] Special Publication No. 11-505377 [Patent Document 3] Japanese Patent Publication No. 2012-238880 [Overview of the project] [Problems that the invention aims to solve]

[0012] One of the objectives is to provide a transistor with stable electrical characteristics. One of the objectives is to provide a transistor with Marie-off electrical characteristics. One of the objectives is to provide a transistor with a small subthreshold swing value. Alternatively, one of the objectives is to provide a transistor with low short-channel effects. One of the objectives is to provide a transistor with low leakage current when not conducting. One of the challenges is to provide transistors with excellent electrical characteristics. Alternatively, high reliability One of the objectives is to provide a transistor with high frequency characteristics. One of our objectives is to provide a generator.

[0013] Alternatively, one of the objectives is to provide a semiconductor device having the transistor. One of the objectives is to provide a module having the semiconductor device. One of the objectives is to provide an electronic device that has such a module, or a new One of the objectives is to provide standard semiconductor devices, or to provide novel modules. One of the objectives is to achieve this. Alternatively, one of the objectives is to provide novel electronic devices.

[0014] Furthermore, the description of these problems does not preclude the existence of other problems. The approach does not need to solve all of these problems. This will become clear from the description in the specification, drawings, claims, etc., and the specification, drawings It is possible to extract other issues from the descriptions in the surfaces, claims, etc. [Means for solving the problem]

[0015] As mentioned earlier, controlling oxygen vacancies in oxide semiconductors is extremely important. To obtain transistor characteristics, it is preferable to minimize oxygen deficiency as much as possible. Furthermore, the compensated oxygen deficiency may be lost again due to damage during the transistor fabrication process, etc. It is also important to form stable bonds to prevent defects.

[0016] Therefore, in one aspect of the present invention, by adding fluorine to the channel formation region of a semiconductor Fluorine compensates for oxygen vacancies in semiconductors and forms stable bonds, thus eliminating oxygen vacancies. By providing compensation, a transistor with stable and good electrical characteristics is provided.

[0017] One aspect of the present invention comprises a gate electrode, a gate insulator, and an oxide semiconductor, and the oxide semiconductor The conductor is a semiconductor device having fluorine in the channel-forming region.

[0018] One aspect of the present invention is that the fluorine concentration in the channel-forming region is 1 × 10 20 Atom s / cm 3 The above 1 x 10 22 atoms / cm 3 The following is a semiconductor device.

[0019] One aspect of the present invention is that the oxide semiconductor is located outside the channel formation region. This is a semiconductor device with a low fluorine concentration in the specified region.

[0020] One aspect of the present invention is that the oxide semiconductor comprises indium, zinc, and element M (where element M is aluminum). A semiconductor device having one or more elements selected from (titanium, gallium, yttrium, or tin) It is placed there.

[0021] One aspect of the present invention is a module having the semiconductor device described above and a printed circuit board. ru.

[0022] One aspect of the present invention is a semiconductor device or module described above, and a speaker. It is an electronic device having, operating keys, or a battery.

[0023] One aspect of the present invention involves forming an oxide semiconductor on a substrate and having a source electrode in contact with the oxide semiconductor. A drain electrode is formed, fluorine is added to the oxide semiconductor, and the oxide semiconductor and source electrode are formed. and a semiconductor device in which an insulator is formed on the drain electrode and a gate electrode is formed on the insulator. This is the manufacturing method.

[0024] Furthermore, in one aspect of the present invention, an oxide semiconductor is formed on a substrate, and fluorine is added to the oxide semiconductor. , a source electrode and a drain electrode are formed in contact with the oxide semiconductor, and the oxide semiconductor, source A semiconductor device in which an insulator is formed on the electrode and drain electrode, and a gate electrode is formed on the insulator. This is the method for making the object.

[0025] Furthermore, in one aspect of the present invention, an oxide semiconductor is formed on a substrate, and a source power is in contact with the oxide semiconductor. Form the electrode and drain electrode, and insulate the oxide semiconductor, source electrode and drain electrode. Form a body, add fluorine to the oxide semiconductor via an insulator, and form a gate electrode on the insulator. This is a method for fabricating semiconductor devices.

[0026] Furthermore, in one aspect of the present invention, a gate electrode is formed on a substrate, and an insulator is formed on the gate electrode, An oxide semiconductor is formed on the terminal electrode via an insulator, and fluorine is added to the oxide semiconductor. A method for fabricating a semiconductor device in which source electrodes and drain electrodes that come into contact with an oxide semiconductor are formed. be.

[0027] Furthermore, in one aspect of the present invention, a gate electrode is formed on a substrate, and an insulator is formed on the gate electrode, An oxide semiconductor is formed on the gate electrode via an insulator, and a source electrode is in contact with the oxide semiconductor. A method for fabricating a semiconductor device in which a drain electrode is formed and fluorine is added to an oxide semiconductor. be.

[0028] One aspect of the present invention is a method for fabricating a semiconductor device in which the addition of fluorine is performed by ion implantation. It is the law.

[0029] One aspect of the present invention is that the oxide semiconductor comprises indium, zinc, and element M (where element M is aluminum). A semiconductor device having one or more elements selected from (titanium, gallium, yttrium, or tin) This is the method for making the object. [Effects of the Invention]

[0030] It is possible to provide a transistor with stable electrical characteristics. Or, normally A transistor having the following electrical characteristics can be provided. Or, a subthreshold It is possible to provide transistors with small swing values. Or, short channel effects It can provide a small transistor. Or, a transistor with low leakage current when not conducting. We can provide transistors. Or, we can provide transistors with excellent electrical characteristics. It is possible to provide highly reliable transistors. A transistor with a high frequency characteristic can be provided.

[0031] Alternatively, a semiconductor device having the transistor can be provided. A module having a device can be provided. Or, the semiconductor device, or the module We can provide electronic equipment having a sphere. Or, we can provide a novel semiconductor device. It is possible to provide a novel module. Or, a novel electronic We can provide the equipment.

[0032] Furthermore, the description of these effects does not preclude the existence of other effects. The embodiment does not need to have all of these effects. Other effects are described in the specification. This will become clear from the descriptions in the drawings and claims, and the specification, drawings, and claims will be clear from the description, drawings, and claims. It is possible to extract other effects from any of these descriptions. [Brief explanation of the drawing]

[0033] [Figure 1] A top view and a cross-sectional view illustrating a transistor according to one aspect of the present invention. [Figure 2] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 3] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 4] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 5] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 6] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 7] A cross-sectional view illustrating a transistor according to one aspect of the present invention. [Figure 8] A cross-sectional view illustrating a transistor according to one aspect of the present invention. [Figure 9] A band diagram according to one aspect of the present invention. [Figure 10] High-resolution TEM image with Cs correction in cross-section of CAAC-OS, and schematic cross-sectional diagram of CAAC-OS. [Figure 11] High-resolution TEM image with Cs correction in the plane of CAAC-OS. [Figure 12] A diagram illustrating the XRD structural analysis of CAAC-OS and single-crystal oxide semiconductors. [Figure 13] A figure showing the electron diffraction pattern of CAAC-OS. [Figure 14] A diagram showing the changes in the crystalline structure of In-Ga-Zn oxide due to electron irradiation. [Figure 15] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 16] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 17] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 18] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 19] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 20] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 21] A top view and a cross-sectional view illustrating a method for manufacturing a transistor according to one aspect of the present invention. [Figure 22] A cross-sectional view illustrating a transistor according to one aspect of the present invention. [Figure 23] A cross-sectional view illustrating a transistor according to one aspect of the present invention. [Figure 24] Circuit diagram showing a semiconductor device according to one aspect of the present invention. [Figure 25] A cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 26] A cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 27] A cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 28] Circuit diagram showing a storage device according to one aspect of the present invention. [Figure 29] A cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 30] A cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 31] A cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 32]A plan view showing a semiconductor device according to one aspect of the present invention. [Figure 33] Block diagram showing a semiconductor device according to one aspect of the present invention. [Figure 34] A cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 35] A cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 36] A perspective view and a cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 37] Block diagram showing a semiconductor device according to one aspect of the present invention. [Figure 38] Circuit diagram showing a semiconductor device according to one aspect of the present invention. [Figure 39] A circuit diagram, a top view, and a cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 40] A circuit diagram and a cross-sectional view showing a semiconductor device according to one aspect of the present invention. [Figure 41] A perspective view showing an electronic device according to one aspect of the present invention. [Figure 42] A diagram illustrating the amount of fluorine added in the depth direction. [Figure 43] A diagram showing the sheet resistance values ​​of the sample. [Figure 44] A figure showing the ESR results of the sample. [Modes for carrying out the invention]

[0034] Embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is described below. It is not limited to the above, and its form and details can be easily changed in various ways, as can be easily seen by those skilled in the art. It is understood that the present invention is to be interpreted as being limited to the embodiments described below. No. Furthermore, when explaining the structure of the invention using drawings, the same reference numerals may refer to different things. It is used consistently across drawings. Furthermore, when referring to similar items, the hatch pattern is the same. Furthermore, sometimes no symbol is assigned.

[0035] Note that in the diagram, the size, thickness of the film (layer), or area has been exaggerated for clarity. They may exist.

[0036] Furthermore, in this specification and other documents, the terms "membrane" and "layer" are interchangeable. It is possible to replace it.

[0037] Furthermore, voltage is defined by a certain potential and a reference potential (e.g., ground potential (GND) or source potential). It often refers to the potential difference between two points. Therefore, it is possible to rephrase voltage as potential. Generally, electric potential (voltage) is relative, and its magnitude is relative to a reference potential. Therefore, it is determined by this. Consequently, even if it is written as "ground potential," The potential is not necessarily 0V. For example, the lowest potential in a circuit may be the "ground potential". There are also cases where the potential in the middle of the circuit becomes the "ground potential." Based on that potential, positive and negative potentials are defined.

[0038] The ordinal numbers "1st" and "2nd" are used for convenience only and do not necessarily indicate the order of processes or layering. It does not indicate order. Therefore, for example, "the first" could be "the second" or "the third." It can be explained by substituting it as appropriate. Also, ordinal numbers as described in this specification, etc. The ordinal numbers used to specify one aspect of the present invention may not always coincide.

[0039] Furthermore, even when the term "semiconductor" is used, if, for example, its conductivity is sufficiently low, it can be referred to as an "insulator." They may have the following characteristics. Also, the boundary between "semiconductors" and "insulators" is ambiguous, and strictly speaking... In some cases, it may be impossible to distinguish between them. Therefore, the term "semiconductor" as used in this specification is used interchangeably with "insulator". In some cases, it can be rephrased. Similarly, the term "insulator" as used herein may be interpreted as "semiconductor." In some cases, this can be rephrased as "...".

[0040] Furthermore, even when the term "semiconductor" is used, if, for example, its conductivity is sufficiently high, it can be referred to as a "conductor." They may have certain characteristics. Also, the boundary between "semiconductors" and "conductors" is ambiguous, and strictly speaking... In some cases, it may be impossible to distinguish between them. Therefore, the term "semiconductor" as used in this specification is used interchangeably with "conductor". In some cases, it can be rephrased. Similarly, the term "conductor" as used herein means "semiconductor." In some cases, this can be rephrased as "...".

[0041] Furthermore, semiconductor impurities refer to components other than the main components that make up the semiconductor, for example, concentration. Elements present in less than 0.1 atomic percent are considered impurities. The presence of impurities can, for example, affect semiconductors. The formation of Density of State (DOS) in the body, and carrier mobility In some cases, the quality may decrease, or the crystallinity may decrease. In the case of semiconductors, impurities that alter the properties of semiconductors include, for example, Group 1 elements and Group 2 elements. These include elements, Group 14 elements, Group 15 elements, and transition metals other than the main component, and in particular, for example, Hydrogen (also found in water), lithium, sodium, silicon, boron, phosphorus, carbon, nitrogen There are elements such as [elements]. In the case of oxide semiconductors, for example, oxygen vacancies can be created by the inclusion of impurities such as hydrogen. It may form. Also, if the semiconductor is silicon, it can change the properties of the semiconductor. As pure substances, for example, Group 1 elements, Group 2 elements, Group 13 elements, and Group 1 elements, excluding oxygen and hydrogen. This includes elements from Group 5, among others.

[0042] Note that channel length refers to, for example, the length of the semiconductor (or transistor) in a top view of a transistor. When the zista is in the ON state, the part of the semiconductor through which current flows and the gate electrode overlap each other. In the region where the channel is formed, the source (source region or source power) This refers to the distance between the electrode and the drain (drain region or drain electrode). In transistors, the channel length is not necessarily the same across all regions. That is, The channel length of a transistor may not be fixed to a single value. Therefore, this specification In the book, the channel length is any one value, the maximum value, in the region where the channel is formed. Use the minimum or average value.

[0043] Channel width refers to, for example, the channel width of a semiconductor (or transistor) when it is in the ON state. The region where the current-carrying part and the gate electrode overlap, or the region where a channel is formed. This refers to the length of the portion in the region where the source and drain face each other. In a transistor, the channel width is not necessarily the same across all regions. That is, The channel width of a transistor may not be fixed to a single value. Therefore, this specification In the book, the channel width is any one value, the maximum value, in the region where the channel is formed. Use the minimum or average value.

[0044] Furthermore, depending on the transistor structure, the channel may actually be formed in the region where the channel is formed. The channel width (hereinafter referred to as the effective channel width) and the top view of the transistor are shown. The channel width (hereinafter referred to as the apparent channel width) may differ from the actual channel width. For example, In transistors with a three-dimensional structure, the effective channel width is shown in the top view of the transistor. The apparent channel width shown in [the relevant section] becomes larger, and its effect can no longer be ignored. There are cases where this occurs. For example, in transistors with a fine and three-dimensional structure, the sides of the semiconductor In some cases, the proportion of the channel-forming region may be large. In that case, in the top view... The effective channel formed is actually greater than the apparent channel width shown. The width will be larger.

[0045] By the way, in transistors with a three-dimensional structure, the effective channel width is measured Estimation can be difficult in some cases. For example, estimating the effective channel width from the design value. In order to do this, it is necessary to assume that the shape of the semiconductor is known. If this information is not precisely known, it is difficult to accurately measure the effective channel width.

[0046] Therefore, in this specification, in the top view of a transistor, the semiconductor and the gate electrode are relative to each other. The apparent length of the portion where the source and drain face each other in the overlapping region. The channel width is called the "Surrounded Channel Width (SCW)". It is sometimes referred to as "L Width." Also, in this specification, it is sometimes simply referred to as "channel width." In some cases, it may refer to the enclosed channel width or the apparent channel width. Or, In this specification, when simply referred to as "channel width," it may refer to the effective channel width. Furthermore, channel length, channel width, effective channel width, apparent channel width, enclosure The channel width and other parameters can be determined by acquiring cross-sectional TEM images and analyzing those images. This allows us to determine the value.

[0047] Furthermore, the field-effect mobility of the transistor and the current value per channel width are calculated to determine this. In some cases, the calculation may be performed using the enclosed channel width. In that case, the effective channel The values ​​may differ from those obtained when calculating using the channel width.

[0048] In this specification, when A is described as having a shape that protrudes from B, the top view is shown. Alternatively, in a cross-sectional view, at least one end of A is located outside at least one end of B. It may be indicated that A has a shape that protrudes from B. If this is the case, for example, in the top view, one end of A is outside the one end of B. It can be reinterpreted as "possessing."

[0049] In this specification, "parallel" means that two straight lines are positioned at an angle of -10° or more and 10° or less. This refers to a state where the temperature is above or below -5°. Therefore, it also includes cases where the temperature is between -5° and 5°. A "row" refers to a state where two straight lines are positioned at an angle of -30° or more and 30° or less. Furthermore, "perpendicular" refers to a state in which two straight lines are positioned at an angle of 80° to 100°. Therefore, it also includes cases where the angle is between 85° and 95°. Also, "approximately perpendicular" means two This refers to a state in which two straight lines are arranged at an angle between 60° and 120°.

[0050] Furthermore, in this specification, if a crystal is trigonal or rhombohedral, it will be represented as a hexagonal crystal system. .

[0051] Furthermore, in the specification, when the term "semiconductor" is used, it can be interpreted as "oxide semiconductor." Other semiconductors include Group 14 semiconductors such as silicon and germanium, and silicon carbide. Germanium silicide, gallium arsenide, indium phosphide, zinc selenide, cadmium sulfide Compound semiconductors such as um, and organic semiconductors can be used.

[0052] (Embodiment 1) This embodiment describes an example of a transistor according to one aspect of the present invention.

[0053] <Transistor 1> Figure 1 shows a transistor according to one aspect of the present invention. Figure 1(A) shows transistor 100 The top view, Figure 1(B), shows the dashed lines A1-A2 and A3- in Figure 1(A). A cross-sectional diagram corresponding to A4 size is shown. Transistor 100 is connected to substrate 400, conductor 413, Insulator 402, semiconductor 406a, semiconductor 406b, semiconductor 406c, and conductor 416a It comprises a conductor 416b, an insulator 412, and a conductor 404.

[0054] The semiconductor 406a, 406b, or 406c in transistor 100 contains fluorine. Fluorine may be present in all three layers. Any layer may have it, or any two layers may have it.

[0055] As shown in this embodiment, the semiconductor in the transistor is formed by multiple layers. In this case, it is preferable that the semiconductor having the channel-forming region contains fluorine. If semiconductor 406b has a channel formation region, semiconductor 406b may contain fluorine. This is preferable.

[0056] Furthermore, the conductor 404 is the first gate electrode (front gate electrode) of transistor 100. It also has the function of being the second of transistor 100. It functions as a gate electrode (also called a back gate electrode). Also, conductor 416 a and conductor 416b serve as the source and drain electrodes of transistor 100. It has the function of a gate insulator.

[0057] Furthermore, the transistor 100 in this embodiment has a top gate with a back gate. This shows a type of transistor, but it is not limited to this. For example, a configuration without a back gate and It is also possible to use a bottom gate structure. In that case, the conductor 413 is a front gate. It functions as a back gate, and conductor 404 functions as a back gate. Also, conductor 404 It's also acceptable to omit this configuration.

[0058] The method for fabricating the transistor 100 shown in Figure 1 will be explained using Figures 2 to 6.

[0059] Figures 2(A), 3(A), 4(A), 5(A), and 6(A) show one embodiment of the present invention. This is a top view illustrating the method for manufacturing the transistor 100. Each top view is indicated by a dashed line. A1-A2 and the dashed line A3-A4 are indicated, and the corresponding cross-sectional view is shown in Figure 2(B), Figure This is shown in Figures 3(B), 4(B), 5(B), and 6(B).

[0060] First, prepare circuit board 400.

[0061] For the substrate 400, for example, an insulating substrate, a semiconductor substrate, or a conductive substrate may be used. Examples of insulating substrates include glass substrates, quartz substrates, sapphire substrates, and stabilized zirconium. These include near-surface substrates (such as yttria-stabilized zirconia substrates) and resin substrates. Also, semiconductors. As for the substrate, for example, a single semiconductor substrate such as silicon or germanium, or silicon carbide Cone, silicon germanium, gallium arsenide, indium phosphide, zinc oxide, gallium oxide There are compound semiconductor substrates made of materials such as um. Furthermore, an insulator is placed inside the aforementioned semiconductor substrate. Semiconductor substrates having regions, for example, SOI (Silicon On Insulator) These include substrates. Conductive substrates include graphite substrates, metal substrates, alloy substrates, and conductive resin substrates. These include substrates containing metallic nitrides, substrates containing metallic oxides, and so on. Furthermore, a substrate in which a conductor or semiconductor is provided on an insulating substrate, and a semiconductor substrate with a conductor or substrates provided with an insulator, substrates provided with a semiconductor or insulator on a conductive substrate, etc. Yes. Alternatively, you may use substrates on which elements are provided. Examples of elements include capacitive elements, resistive elements, switch elements, light-emitting elements, and memory elements.

[0062] Furthermore, a flexible substrate may be used as the substrate 400. One method for creating a transistor is to fabricate a transistor on a non-flexible substrate, and then... Another method involves peeling off the zista and transferring it to the flexible substrate 400. In that case, It is preferable to provide a release layer between the non-flexible substrate and the transistor. Note that the substrate 400 is Alternatively, a sheet, film, or foil made of woven fibers may be used. Also, the substrate 400 It may also be stretchable. Furthermore, when the bending or pulling of the substrate 400 is stopped, it returns to its original shape. It may have the property of returning to its original shape. Alternatively, it may have the property of not returning to its original shape. Substrate 4 The thickness of 00 is, for example, 5 μm or more and 1000 μm or less, preferably 10 μm or more and 700 μm or less. The thickness should be less than or equal to m, more preferably between 15 μm and 500 μm. When the substrate 400 is thinned... This makes it possible to lighten semiconductor devices. Also, by making the substrate 400 thinner, glass When using any method, the material may be elastic, or when bending or pulling is stopped, it may return to its original shape. It may have the property of returning to its original state. Therefore, if the semiconductor device on the substrate 400 is dropped or otherwise damaged, It can mitigate impacts and other shocks applied to it. In other words, it can provide a robust semiconductor device. Cut.

[0063] The flexible substrate 400 can be, for example, metal, alloy, resin, or glass. Alternatively, those fibers can be used. The substrate 400, which is a flexible substrate, undergoes linear expansion. A lower ratio is preferable as it suppresses deformation due to the environment. The substrate 400 is a flexible substrate. For example, the coefficient of thermal expansion is 1 × 10⁻⁶. -3 / K or less, 5×10 -5 / K or less, or 1×1 0 -5 Any material with a K value of 0.5 or less should be used. Examples of resins include polyester and poly Olefins, polyamides (nylon, aramid, etc.), polyimides, polycarbonates, Examples include acrylic. In particular, aramid has a low coefficient of thermal expansion, making it suitable for flexible substrates. 400 is preferred.

[0064] Next, a conductive film is deposited. The conductive film is deposited using sputtering, chemical vapor deposition (CVD), etc. Chemical Vapor Deposition (MB) method, molecular beam epitaxy (MB) E: Molecular Beam Epitaxy or pulsed laser deposition (PL) D: Pulsed Laser Deposition) method, atomic layer deposition (ALD: At This can be done using methods such as the omic layer deposition method.

[0065] Furthermore, the CVD method is a plasma CVD (PECVD) method that utilizes plasma. Processed CVD (CVD), thermal CVD (TCVD) which utilizes heat. Method D) can be classified into methods such as photoCVD (Photo-CVD), which utilizes light. Depending on the source gas, the process can be performed using metal CVD (MCVD) or organometallic CVD. It can be divided into MOCVD (Metal Organic CVD) methods.

[0066] The PECVD method yields high-quality films at relatively low temperatures. The TCVD method, on the other hand, uses plasma... Because it does not use plasma, this is a film deposition method that does not cause plasma damage to the workpiece. The wiring, electrodes, and elements (transistors, capacitive elements, etc.) included in semiconductor devices are plastic. It can sometimes charge up by receiving charge from Zuma. At this time, the accumulated charge This can cause damage to wiring, electrodes, and components contained in semiconductor devices. On the other hand, In the case of TCVD methods that do not use plasma, such plasma damage does not occur, so This can increase the yield of conductive devices. In addition, in the TCVD method, plasma during film deposition Because no damage occurs, it is easier to obtain a film with fewer defects.

[0067] Furthermore, the ALD method is a film deposition method that can minimize plasma damage to the workpiece. Yes. Also, the ALD method does not cause plasma damage during film deposition, so it produces films with fewer defects. It is easy to obtain.

[0068] CVD and ALD are film deposition methods in which particles emitted from a target or other source are deposited. In contrast, this is a film formation method in which a film is formed by a reaction on the surface of the object being treated. This film formation method is less affected by the shape of the workpiece and has good step-level coverage. The ALD method has excellent step coverage and excellent thickness uniformity, so the aspect ratio It is suitable for coating surfaces with high apertures. However, the ALD method has a relatively slow film deposition rate. Because the deposition rate is slow, it is not suitable for use in combination with other film deposition methods that have a high deposition rate, such as CVD. It can be preferable in some cases.

[0069] The CVD and ALD methods allow control of the composition of the resulting film by adjusting the flow rate ratio of the source gas. This is possible. For example, in the CVD method and ALD method, the flow rate ratio of the raw material gas can be adjusted to any A film of a certain composition can be formed. Also, for example, in the CVD method and ALD method, the film is formed. By changing the flow rate ratio of the raw material gas, a film with a continuously changing composition is formed. This is possible. When forming a film while changing the flow rate ratio of the raw material gas, multiple deposition chambers can be used. Compared to the method used for film deposition, the time required for film deposition is reduced by eliminating the time spent on transport and pressure adjustment. This is possible. Therefore, it may be possible to increase the productivity of semiconductor devices.

[0070] Next, a resist is formed on the conductor, and the conductor 413 is formed by processing using the resist. To achieve. Note that when simply forming a resist, an anti-reflective layer is formed beneath the resist. This also includes cases where...

[0071] The resist is removed after the object has been processed by etching or other methods. This involves plasma treatment and / or wet etching. Therefore, plasma ashing is preferable. If the removal of resist, etc. is insufficient, 0.00 Hydrofluoric acid and / or ozone in a concentration of 1 volume or more and 1 volume or less You may remove any remaining resist or other residue with water or other means.

[0072] Examples of conductors that become conductor 413 include boron, nitrogen, oxygen, fluorine, silicon, Phosphorus, aluminum, titanium, chromium, manganese, cobalt, nickel, copper, zinc, gallium Um, yttrium, zirconium, molybdenum, ruthenium, silver, indium, tin, Conductors containing one or more tantalum and tungsten can be used in a single layer or in a multilayer structure. For example, it may be an alloy or compound, such as a conductor containing aluminum, copper and titanium. Conductors containing copper and manganese, conductors containing indium, tin and oxygen Conductors containing titanium and nitrogen may also be used.

[0073] Next, the insulator 402 is deposited (see Figures 2(A) and 2(B)). Thin film deposition is performed using methods such as sputtering, CVD, MBE, PLD, or ALD. It is possible to do so.

[0074] Examples of insulators 402 include boron, carbon, nitrogen, oxygen, fluorine, magnesium, and Aluminum, silicon, phosphorus, chlorine, argon, gallium, germanium, yttrium An insulator containing zirconium, lanthanum, neodymium, hafnium, or tantalum, in a single layer Alternatively, they can be used in a laminated configuration. For example, as the insulator 402, aluminum oxide, acid Magnesium oxide, silicon oxide, silicon oxide nitride, silicon oxide nitride, silicon nitride, Gallium oxide, germanium oxide, yttrium oxide, zirconium oxide, lanthanum oxide , neodymium oxide, hafnium oxide or tantalum oxide may be used.

[0075] In addition, it is preferable that the insulator 402 is an insulator having excess oxygen and / or hydrogen traps. Preferably.

[0076] An insulator having excess oxygen, in temperature programmed desorption gas spectrometry (TDS analysis), at a surface temperature range of 100 °C or higher 700 °C or lower, or 100 °C or higher and 500 °C or lower, may release oxygen (in terms of the number of oxygen atoms) of 1×10 18 atoms / cm 3 or more, 1×10 19 atoms / cm 3 or more or 1×10 20 at oms / cm 3 or more. The method for measuring the amount of oxygen released using TDS analysis will be described below.

[0077] The total amount of gas released when the measurement sample is subjected to TDS analysis is proportional to the integrated value of the ionic strength of the released gas. And the total amount of gas can be calculated by comparison with a standard sample.

[0078] For example, from the TDS analysis results of a silicon substrate containing hydrogen with a predetermined density as a standard sample, and the TDS analysis results of the measurement sample, the amount of oxygen molecules released from the measurement sample (N

[0079] O2 ) can be obtained by the following formula. Here, it is assumed that all the gas detected with a mass-to-charge ratio of 32 obtained by TDS analysis is derived from oxygen molecules. Although the mass-to-charge ratio of CH3OH is 32, it is not considered here as it has a low possibility of existence. Also, oxygen atoms of isotope mass number 17 Here, it is assumed that all the gas detected with a mass-to-charge ratio of 32 obtained by TDS analysis is derived from oxygen molecules. Although the mass-to-charge ratio of CH3OH is 32, it is not considered here as it has a low possibility of existence. Also, oxygen atoms of isotope mass number 17 Regarding oxygen atoms and oxygen molecules containing oxygen atoms with a mass number of 18, the abundance in nature The rate is so small that it will not be considered.

[0080] N O2 =N H2 / S H2 ×S O2 ×α

[0081] N H2 This value represents the density of hydrogen molecules detached from the standard sample. H2 The standard test This is the integral value of the ionic intensity when the material is analyzed by TDS. Here, the reference value of the standard sample is N H2 / S H2 Let's assume that. S O2 This is the integral value of the ionic intensity when the sample is subjected to TDS analysis. Yes, it exists. α is a coefficient that affects the ionic strength in TDS analysis. For details of the formula shown above, see below. For further information, please refer to Japanese Patent Publication No. 6-275697. Note that the amount of oxygen released is electron Using the EMD-WA1000S / W temperature-controlled desorption analyzer manufactured by Kagaku Co., Ltd., as a standard sample The measurement is performed using a silicon substrate containing a certain amount of hydrogen atoms.

[0082] Furthermore, in TDS analysis, some oxygen is detected as oxygen atoms. Oxygen molecules and oxygen atoms The ratio of these can be calculated from the ionization rate of oxygen molecules. Note that α above represents the oxygen component. Because it includes the ionization rate of the oxygen atom, by evaluating the amount of oxygen molecule released, the amount of oxygen atom released can be determined. Even if they are present, it can still be estimated.

[0083] Note N O2 This is the amount of oxygen molecules released. The amount released when converted to oxygen atoms is the amount of oxygen molecules. This will be twice the amount released.

[0084] Alternatively, an insulator that releases oxygen by heat treatment may contain peroxide radicals. Specifically, the spin density due to peroxide radicals is 5×10 17 spins / cm 3 or more. Note that an insulator containing peroxide radicals may have a signal with a g value near 2.01 and asymmetric in the electron spin resonance method (ES R:Electron Spin Resonance).

[0085] Also, the insulator 402 may have a function of preventing the diffusion of impurities from the substrate 400 or the like.

[0086] Next, a semiconductor that becomes the semiconductor 406a is formed. The formation of the semiconductor that becomes the semiconductor 406a can be performed using a sputtering method, a CVD method, an MBE method, a PLD method, an ALD method, or the like.

[0087] Next, by adding oxygen, the semiconductor that becomes the semiconductor 406a may be made to contain excess oxygen. The addition of oxygen can be performed, for example, by the ion implantation method with an acceleration voltage of 2 kV or more and 10 kV or less and a dose amount of 5×10 ions / cm 14 or more and 1×10 2 ions / cm 17 or less 2

[0088] Next, fluorine may be added to the semiconductor that becomes the semiconductor 406a. Note that the addition of oxygen to the semiconductor that becomes the semiconductor 406a and the addition of fluorine to the semiconductor that becomes the semiconductor 406a may be performed in the reverse order.

[0089] The addition of fluorine can be performed, for example, by the ion implantation method with an acceleration voltage of 1 kV or more and 200 kV or less. Preferably, it is 5 kV or more and 100 kV or less, and the dose amount is 5×10 19 ions / cm 3 or more, preferably 1×10 ions / cm 22 ions / cm 3 or less, and preferably 1×10 20 ions / cm 3 or more and 1 ×10 22 ions / cm 3 or less, and it may be performed as such.

[0090] Next, a semiconductor that becomes the semiconductor 406b is formed. The formation of the semiconductor that becomes the semiconductor 406b is performed using a sputtering method, a CVD method, an MBE method, a PLD method, an ALD method, etc. It can be done. Note that by continuously performing the formation of the semiconductor that becomes the semiconductor 406a and the formation of the semiconductor that becomes the semiconductor 406b without exposing them to the atmosphere, the incorporation of impurities into the film and at the interface can be reduced.

[0091] Next, it is preferable to perform a heat treatment. By performing the heat treatment, the hydrogen concentration of the semiconductor that becomes the semiconductor 406a and the semiconductor that becomes the semiconductor 406b may be reduced . Also, the oxygen deficiency of the semiconductor that becomes the semiconductor 406a and the semiconductor that becomes the semiconductor 406b may be reduced . The heat treatment may be performed at 250°C or more and 650°C or less, preferably 450°C or more and 600°C or less, and more preferably 520°C or more and 570°C or less. The heat treatment may be performed in an inert gas atmosphere, or in an atmosphere containing 10 ppm or more, 1% or more, or 10% or more of an oxidizing gas. The heat treatment may be performed under reduced pressure. Or, the heat treatment may be , after heat treatment in an inert gas atmosphere, heat treatment is performed in an atmosphere containing 10 p [[ID=50--52]]pm or more, 1% or more, or 10% or more of an oxidizing gas in order to supplement the desorbed oxygen. The heat treatment ​​Therefore, the crystallinity of the semiconductor that becomes semiconductor 406a and the semiconductor that becomes semiconductor 406b is increased. It can do things like remove impurities such as hydrogen and water.

[0092] Next, fluorine is added to the semiconductor that will become semiconductor 406a and the semiconductor that will become semiconductor 406b. It is also permissible to use semiconductors that become semiconductor 406a and semiconductors that become semiconductor 406b. Heat treatment and fluorine in the semiconductor that will become semiconductor 406a and the semiconductor that will become semiconductor 406b. The addition of and can be done in any order.

[0093] Fluorine addition is performed, for example, by ion implantation, with an accelerating voltage of 1kV to 200kV. Preferably, the voltage should be between 5kV and 100kV, and the dose should be 5 × 10⁻¹⁰ 19 ions / cm 3 Below top 5×10 22 ions / cm 3 The following is preferably 1 × 10 20 ions / cm 3 The above 1 ×10 22 ions / cm 3 You can do it as follows:

[0094] Next, a resist or the like is formed on the semiconductor that will become semiconductor 406b, and the resist is used for processing. This forms semiconductors 406b and 406a (see Figures 3(A) and 3(B)). . ) .

[0095] Next, a conductive film is deposited. The conductive film is deposited by sputtering, CVD, MBE, or This can be done using methods such as the PLD method and ALD method.

[0096] Examples of conductors include boron, nitrogen, oxygen, fluorine, silicon, phosphorus, and aluminum. , titanium, chromium, manganese, cobalt, nickel, copper, zinc, gallium, yttrium , zirconium, molybdenum, ruthenium, silver, indium, tin, tantalum and tungsten A conductor containing one or more of them may be used in a single layer or in a laminated form. For example, it may be an alloy or a compound, and a conductor containing aluminum, a conductor containing copper and titanium, a conductor containing copper and manganese, a conductor containing indium, tin and oxygen, a conductor containing titanium and nitrogen etc. may be used.

[0097] Next, a resist or the like is formed on the conductor, and the conductor 416a and the conductor 416b are formed using the resist (see FIGS. 4(A) and 4(B)).

[0098] Next, fluorine may be added to the semiconductor 406a and the semiconductor 406b. The addition of fluorine can be performed using the conductor 416a and the conductor 416b as masks. Thereby, in the semiconductor 406a and the semiconductor 406b, fluorine can be selectively added to regions that do not overlap with the conductor 416a and the conductor 416b.

[0099] Also, for example, by reducing the thicknesses of the conductor 416a and the conductor 416b, in the semiconductor 406a and the semiconductor 406b, fluorine may also be added to regions that overlap with the conductor 416a and the conductor 416b. Thereby, semiconductors 406a and 406b having different fluorine concentrations in regions that overlap with and regions that do not overlap with the conductor 416a and the conductor 416b can be formed. For example, in the semiconductor 406a and the semiconductor 4 06b, the regions that overlap with the conductor 416a and the conductor 416b are the conductor 416 0 The fluorine concentration is lower in regions that do not overlap with a and conductor 416b.

[0100] Fluorine addition is performed, for example, by ion implantation, with an accelerating voltage of 1kV to 200kV. Preferably, the voltage should be between 5kV and 100kV, and the dose should be 5 × 10⁻¹⁰ 19 ions / cm 3 Below top 5×10 22 ions / cm 3 The following is preferably 1 × 10 20 ions / cm 3 The above 1 ×10 22 ions / cm 3 You can do it as follows:

[0101] Here, for example, the conductor 413 is the gate electrode, the insulator 402 is the gate insulator, and the conductor 416 If a is the source electrode and conductor 416b is the drain electrode, the process is completed up to Figure 4. A transistor having a Tom gate structure may also be used.

[0102] Next, the semiconductor 436c is deposited. The semiconductor 436c is deposited by sputtering, CVD, etc. This can be done using methods such as the MBE method, PLD method, or ALD method. Semiconductor 436c Before film formation, semiconductor 406a, semiconductor 406b, conductor 416a and conductor 416b The surface may be etched. For example, etching can be performed using a plasma containing a noble gas. This allows for the continuous deposition of semiconductor 436c without exposure to the atmosphere. As a result, semiconductor 406a, semiconductor 406b, conductor 416a and conductor 416b, This reduces the incorporation of impurities into the interface between semiconductor 436c and other materials. Impurities present in the substrate may diffuse more easily than impurities in the film. Therefore, these impurities may diffuse more easily. By reducing the inclusion of contaminants, stable electrical characteristics can be imparted to the transistor. ru.

[0103] Next, fluorine may be added to semiconductors 406a, 406b, and 436c. Furthermore, fluorine is added to all of semiconductors 406a, 406b, and 436c. It is not necessary to add fluorine; however, fluorine may be added to either one or either of the two layers.

[0104] Fluorine addition is performed, for example, by ion implantation, with an accelerating voltage of 1kV to 200kV. Preferably, the voltage should be between 5kV and 100kV, and the dose should be 5 × 10⁻¹⁰ 19 ions / cm 3 Below top 5×10 22 ions / cm 3 The following is preferably 1 × 10 20 ions / cm 3 The above 1 ×10 22 ions / cm 3 You can do it as follows:

[0105] Next, the insulator 442 is deposited. The insulator 442 is deposited by sputtering, CVD, This can be performed using methods such as MBE, PLD, or ALD. By performing the deposition of film c and the deposition of insulator 442 in succession without exposure to the atmosphere, the film is formed Furthermore, it is possible to reduce the incorporation of impurities into the interface.

[0106] Examples of insulators 442 include boron, carbon, nitrogen, oxygen, fluorine, magnesium, and Aluminum, silicon, phosphorus, chlorine, argon, gallium, germanium, yttrium An insulator containing zirconium, lanthanum, neodymium, hafnium, or tantalum, in a single layer Alternatively, they can be used in a laminated configuration. For example, as the insulator 442, aluminum oxide, acid Magnesium oxide, silicon oxide, silicon oxide nitride, silicon oxide nitride, silicon nitride, Gallium oxide, germanium oxide, yttrium oxide, zirconium oxide, lanthanum oxide Neodymium oxide, hafnium oxide, or tantalum oxide may be used.

[0107] Next, through the insulator 442, semiconductors 406a, 406b, and 436c Fluorine may be added. Note that semiconductors 406a, 406b and 436 It is not necessary to add fluorine to all of c; fluorine can be added to any one or two layers. It may be added. Fluorine may also be added to the insulator 442.

[0108] Fluorine addition is performed, for example, by ion implantation, with an accelerating voltage of 1kV to 200kV. Preferably, the voltage should be between 5kV and 100kV, and the dose should be 5 × 10⁻¹⁰ 19 ions / cm 3 Below top 5×10 22 ions / cm 3 The following is preferably 1 × 10 20 ions / cm 3 The above 1 ×10 22 ions / cm 3 You can do it as follows:

[0109] Next, the conductive material 434 is deposited. The conductive material 434 is deposited by sputtering, CVD, This can be carried out using methods such as MBE, PLD, or ALD. Note that insulator 442 By performing the film formation of the film and the film formation of the conductor 434 in succession without exposure to the atmosphere, the film is formed This reduces the incorporation of impurities into the interface (see Figures 5(A) and 5(B)). ).

[0110] Examples of conductors 434 include boron, nitrogen, oxygen, fluorine, silicon, phosphorus, and aluminum. Nium, titanium, chromium, manganese, cobalt, nickel, copper, zinc, gallium, yt Rium, zirconium, molybdenum, ruthenium, silver, indium, tin, tantalum, and A conductor containing one or more types of tungsten can be used in a single layer or in a multilayer structure. For example, They may be alloys or compounds, including conductors containing aluminum, and conductors containing copper and titanium. Conductors containing copper and manganese, conductors containing indium, tin and oxygen, titanium Conductors containing nitrogen may also be used.

[0111] Next, a resist or the like is formed on the conductor 434, and the resist is used to process the conductor 40 4 is formed. Also, the insulator 442 is processed using the resist or conductor 404, and A marginal body 412 is formed. Furthermore, the resist, conductor 404, or insulator 412 is used to form a semi-semi The conductor 436c is processed to form the semiconductor 406c. The semiconductor 406c and the insulator 412 and the conductor The electric body 404 and the transistor have similar shapes when viewed from above, but according to one aspect of the present invention Zistors are not limited to this shape. For example, semiconductor 406c and insulator 412 The conductor 404 may be processed using a different resist. For example, an insulator 412 may be formed. After that, a conductive film to become the conductive material 404 may be formed, or after forming the conductive material 404, A resist or the like may be formed separately on the insulator that forms the edge 412. Also, for example, a semiconductor 406c may be connected to an adjacent transistor, etc. (Figure 6(A) and Figure 6( See B). ).

[0112] Next, an insulator may be deposited. The insulator can be deposited by sputtering, CVD, or MBE. This can be done using methods such as the PLD method or ALD method.

[0113] Examples of insulators include boron, carbon, nitrogen, oxygen, fluorine, magnesium, and aluminum. Um, silicon, phosphorus, chlorine, argon, gallium, germanium, yttrium, zirconium An insulator containing conium, lanthanum, neodymium, hafnium, or tantalum, in a single layer, Alternatively, it can be used in a laminated configuration. The insulator is preferably aluminum oxide, silicon nitride, Silicon nitride, gallium oxide, yttrium oxide, zirconium oxide, lanthanum oxide, acid Insulators containing neodymium oxide, hafnium oxide, or tantalum oxide, in single layers or multilayered Use it.

[0114] The insulator preferably functions as a barrier layer. The insulator may, for example, contain oxygen or It has the function of blocking hydrogen. In addition, the insulator is, for example, insulator 402 Alternatively, a higher ability to block oxygen and / or hydrogen is preferred over that of insulator 412. It's nice.

[0115] By following the above steps, a transistor 100 according to one aspect of the present invention can be manufactured.

[0116] As described above, by adding fluorine to the channel formation region of the semiconductor, It can compensate for oxygen deficiency. Furthermore, fluorine forms a stable bond, thus compensating for oxygen deficiency. To provide a transistor with stable and good electrical characteristics by compensating for this. It is possible.

[0117] As shown in Figure 6(B), the electric field of conductors 404 and 413 causes semiconductor 40 6b can be electrically surrounded (the electric field generated from the conductor electrically surrounds the semiconductor). The structure of the transistor surrounding it is called a surrounded channel (s-cha This is called a nnel structure. Therefore, the entire structure of semiconductor 406b (top, bottom, and sides) A channel is formed. In an s-channel structure, the source-dray of the transistor A large current can be passed between the terminals, and the current during conduction (on-current) can be increased.

[0118] Furthermore, if the transistor has an s-channel structure, the side surface of semiconductor 406b also A channel is formed. Therefore, the thicker the semiconductor 406b, the larger the channel formation region. In other words, the thicker the semiconductor 406b, the higher the on-current of the transistor can be. Also, the thicker the semiconductor 406b, the higher the proportion of the region where carrier controllability is possible. Therefore, the subthreshold swing value can be reduced. For example, 10nm or more, Preferably 20 nm or more, more preferably 40 nm or more, and more preferably 100 nm or less. A semiconductor 406b having the above thickness region can be used. However, the productivity of semiconductor devices is low. Because it may be lowered, for example, 300 nm or less, preferably 200 nm or less, even more preferably Alternatively, the semiconductor 406b may have a region with a thickness of 150 nm or less.

[0119] Because it provides a high on-current, the s-channel structure is used in miniaturized transistors. It can be said to be a suitable structure. Because the transistor can be miniaturized, it is a semiconductor having the transistor. The device can be made into a highly integrated, high-density semiconductor device. For example, The lunger has a channel length of preferably 40 nm or less, more preferably 30 nm or less. More preferably, the region has a range of 20 nm or less, and the transistor has a preferred channel width. The region is 40 nm or less, more preferably 30 nm or less, and more preferably 20 nm or less. It holds.

[0120] Note that the conductive material 413 does not need to be formed (see Figure 7(A)). Also, the insulator 412 Alternatively, the semiconductor 406c may be in a shape that protrudes from the conductor 404 (see Figure 7(B)). ). Furthermore, it is not necessary to process the insulator 442 and the semiconductor 436c (see Figure 7(C)). ). Also, the width of the conductor 413 in the A1-A2 cross section is greater than that of the semiconductor 406b. This is also fine (see Figure 8(A)). Also, the conductor 413 and the conductor 404 are in contact through the opening. It is also permissible to do so (see Figure 8(B)). Furthermore, it is not necessary to provide the conductor 404 (see Figure 8(C)). )reference.).

[0121] <Semiconductors> As shown in this embodiment, semiconductor 406a and semiconductor 40 are located above and below semiconductor 406b. In some cases, the electrical characteristics of a transistor can be improved by adding 6c.

[0122] Semiconductor 406b is, for example, an oxide semiconductor containing indium. Semiconductor 406b is, For example, the presence of indium increases the carrier mobility (electron mobility). 406b preferably contains element M. Element M is preferably aluminum or gallium. , yttrium or tin, etc. Other elements applicable to element M include ho U, silicon, titanium, iron, nickel, germanium, zirconium, molybdenum, Examples include tungsten, cerium, neodymium, hafnium, tantalum, and tungsten. However, In some cases, element M may be a combination of multiple elements as mentioned above. For example, an element with a high bonding energy with oxygen. It is an element with a higher energy than zinc. Alternatively, element M is, for example, the energy of oxide semiconductors. It is an element that has the function of increasing the gap. Also, semiconductor 406b is preferable when it contains zinc. It seems that oxide semiconductors can sometimes crystallize more easily when zinc is included.

[0123] However, semiconductor 406b is not limited to indium-containing oxide semiconductors. 6b is, for example, zinc tin oxide, gallium tin oxide, etc., which do not contain indium, sub These include lead-containing oxide semiconductors, gallium-containing oxide semiconductors, tin-containing oxide semiconductors, etc. That's fine.

[0124] Semiconductor 406b uses, for example, an oxide with a large energy gap. Semiconductor 406 The energy gap of b is, for example, 2.5 eV to 4.2 eV, preferably 2.8 eV. The voltage should be between eV and 3.8eV, and more preferably between 3eV and 3.5eV.

[0125] For example, semiconductors 406a and 406c contain oxygen other than that which constitutes semiconductor 406b. It is an oxide semiconductor composed of one or more elements, or two or more elements. One or more elements other than oxygen make up semiconductor 406a and semiconductor 406 Since c is formed, the interface between semiconductor 406a and semiconductor 406b, and semiconductor 406b Defect levels are less likely to form at the interface between the semiconductor 406c and the semiconductor 406c.

[0126] Semiconductors 406a, 406b, and 406c contain at least indium. This is preferable. Furthermore, when semiconductor 406a is In-M-Zn oxide, the sum of In and M is When set to 100 atomic%, preferably In is less than 50 atomic and M is 50 Higher than atomic%, and more preferably less than 25 atomic% of In and 75% of M. It is assumed to be higher than tomic%. Also, when semiconductor 406b is In-M-Zn oxide, When the sum of n and M is taken as 100 atomic%, preferably In is 25 atomic. Higher than %, M is less than 75 atomic%, and more preferably In is 34 atomic% The ratio should be higher, and M should be less than 66 atomic%. Also, semiconductor 406c should be In-M-Zn. When it is an oxide, if the sum of In and M is 100 atomic%, preferably In is Less than 50 atomic%, M is higher than 50 atomic%, and more preferably In is 2 Less than 5 atomic%, M should be higher than 75 atomic%. Note that semiconductor 406c You may use the same type of oxide as semiconductor 406a. However, semiconductor 406a or / And in some cases, semiconductor 406c does not need to contain indium. For example, semiconductor 406a and / or semiconductor 406c may be gallium oxide. The number of atoms of each element contained in body 406a, semiconductor 406b, and semiconductor 406c is simple It doesn't have to be an integer ratio.

[0127] Semiconductor 406b has a greater electron affinity than semiconductors 406a and 406c. Materials are used. For example, semiconductor 406b is made from semiconductor 406a and semiconductor 406c. Electron affinity of 0.07 eV or more and 1.3 eV or less, preferably 0.1 eV or more and 0.7 eV or less Furthermore, it is more preferable to use an oxide with a voltage of 0.15 eV or more and 0.4 eV or less. The affinity force is the energy difference between the vacuum level and the lower end of the conduction band.

[0128] Furthermore, indium gallium oxide has low electron affinity and high oxygen blocking properties. Therefore, it is preferable that semiconductor 406c contains indium gallium oxide. The ratio of particles [Ga / (In+Ga)] is, for example, 70% or more, preferably 80% or more, and further Preferably, it should be 90% or more.

[0129] In this manner, semiconductors 406a and 406c are arranged above and below semiconductor 406b. In the transistor, when a gate voltage is applied, semiconductor 406a, semiconductor 406b, semiconductor Channels are formed in the semiconductor 406b, which has a high electron affinity, among the 406c members.

[0130] Here, between semiconductor 406a and semiconductor 406b, It may have a mixed region with . Also, between semiconductor 406b and semiconductor 406c, It may have mixed regions of semiconductor 406b and semiconductor 406c. Mixed regions are defect zones. The density of semiconductors 406a, 406b, and 406c becomes lower. In a laminate, the energy changes continuously near each interface (also known as continuous bonding). This is the band diagram (see Figure 9). Note that semiconductors 406a and 406b and In some cases, it may be difficult to clearly distinguish between the different interfaces of semiconductor 406c.

[0131] At this time, the electrons are not in semiconductor 406a and semiconductor 406c, but in semiconductor 406b. It mainly moves through the middle. As mentioned above, at the interface between semiconductor 406a and semiconductor 406b The defect level density, and the defect level density at the interface between semiconductor 406b and semiconductor 406c. By lowering the degree, the movement of electrons in semiconductor 406b is less inhibited. This allows for an increase in the on-current of the transistor.

[0132] The on-current of a transistor can be increased as the factors that hinder electron movement are reduced. Yes, it is possible. For example, if there are no factors hindering electron movement, it is estimated that electrons will move efficiently. Electron movement is inhibited, for example, when the physical irregularities of the channel-forming region are large. It will be done.

[0133] To increase the on-current of the transistor, for example, the top or bottom surface of semiconductor 406b (The surface to be formed, in this case semiconductor 406a) within a 1 μm × 1 μm area, the mean square of the squares Root Mean Square (RMS) roughness is less than 1 nm, preferably 0.6 It should be less than nm, more preferably less than 0.5 nm, and more preferably less than 0.4 nm. Furthermore, the average surface roughness (also called Ra) in a 1 μm × 1 μm area is less than 1 nm. Preferably less than 0.6 nm, more preferably less than 0.5 nm, and more preferably 0.4 nm. It should be less than m. Also, the maximum height difference (also called PV) within a 1 μm × 1 μm area. .) is less than 10 nm, preferably less than 9 nm, more preferably less than 8 nm, The minimum is less than 7 nm. RMS roughness, Ra, and PV are measured by SII Nanotech. Measurements are taken using a scanning probe microscope system SPA-500 manufactured by Knology Co., Ltd. It is possible.

[0134] Furthermore, in order to increase the on-current of the transistor, the thickness of the semiconductor 406c should be as small as possible. Preferably, less than 10 nm, preferably 5 nm or less, and even more preferably 3 nm or less. The semiconductor 406c may have a region of the above. On the other hand, the semiconductor 406c has channel formation To the semiconductor 406b, elements other than oxygen that constitute the adjacent insulator (hydrogen, silicon, etc.) It has a function to block (and) from entering. Therefore, semiconductor 406c has a certain It is preferable that it has a thickness of a certain degree. For example, 0.3 nm or more, preferably 1 nm or more. More preferably, the semiconductor 406c has a region with a thickness of 2 nm or more. The semiconductor 406c suppresses the outward diffusion of oxygen released from the insulator 402, etc. It is preferable that it has the property of blocking oxygen.

[0135] Furthermore, in order to increase reliability, semiconductor 406a should be thick and semiconductor 406c should be thin. Preferred. For example, 10 nm or more, preferably 20 nm or more, and more preferably 40 nm. More preferably, the semiconductor 406a has a region with a thickness of 60 nm or more. By increasing the thickness of semiconductor 406a, from the interface between the adjacent insulator and semiconductor 406a This allows the distance to the semiconductor 406b where the channel is formed to be increased. However, the semiconductor The productivity of the device may decrease, for example, 200 nm or less, preferably 120 nm. The semiconductor 406a has a region with a thickness of m or less, more preferably 80 nm or less. stomach.

[0136] For example, between semiconductor 406b and semiconductor 406a, secondary ion mass spectrometry (SIMS) is performed. In Secondary Ion Mass Spectrometry, 1×1 0 16 atoms / cm 3 Above 1×10 19 atoms / cm 3 Below, preferably 1×1 0 16 atoms / cm 3 Above 5×10 18 atoms / cm 3 Below, more preferably 1×10 16 atoms / cm 3 Above 2×10 18 atoms / cm 3 Of the silicon concentration Degree, and has a region. Also, between the semiconductor 406b and the semiconductor 406c, in SIMS It is, 1×10 16 atoms / cm 3 Above 1×10 19 atoms / cm 3 Below, preferably Preferably 1×10 16 atoms / cm 3 Above 5×10 18 atoms / cm 3 Below, further Preferably 1×10 16 atoms / cm 3 Above 2×10 18 atoms / cm 3 Below Of the silicon concentration and has a region.

[0137] Also, in order to reduce the hydrogen concentration of the semiconductor 406b, it is preferable to reduce the hydrogen concentration of the semiconductor 406a and the semiconductor 406 c. The semiconductor 406a and the semiconductor 406c are, in SIMS It is, 1×10 16 atoms / cm 3 Above 2×10 20 atoms / cm 3 Below, Preferably 1×10 16 atoms / cm 3 Above 5×10 19 atoms / cm 3below, Better 1 × 10 16 atoms / cm 3 The above 1 x 10 19 atoms / cm 3 Below Below, more preferably 1 × 10 16 atoms / cm 3 The above 5 x 10 18 ate / c m 3 It has a region with the following hydrogen concentrations. Also, to reduce the nitrogen concentration of semiconductor 406b Therefore, it is preferable to reduce the nitrogen concentration of semiconductors 406a and 406c. 06a and semiconductor 406c are 1 × 10 in SIMS. 15 atoms / cm 3 Below Top 5×10 19 atoms / cm 3 The following is preferably 1 × 10 15 atoms / cm 3 Below Top 5×10 18 atoms / cm 3 More preferably 1 × 10 15 atoms / cm 3 The above 1 x 10 18 atoms / cm 3 More preferably 1 × 10 15 atoms / cm 3 The above 5 x 10 17 atoms / cm 3 It has a region with the following nitrogen concentrations.

[0138] The three-layer structure described above is just one example. For example, a two-layer structure without semiconductor 406a or semiconductor 406c. The structure itself is also acceptable. Alternatively, it can be above or below semiconductor 406a, or on semiconductor 406c. Above or below, semiconductors 406a, 406b, and 406c are shown as examples. It may also be a four-layer structure having any one of the semiconductors. Alternatively, on top of semiconductor 406a or at least two locations below semiconductor 406a, above semiconductor 406c, or below semiconductor 406c. In addition, the semiconductors exemplified as semiconductor 406a, semiconductor 406b, and semiconductor 406c It may also be an n-layer structure (where n is an integer greater than or equal to 5) having one or more of the following properties.

[0139] <About the structure of oxide semiconductors> The structure of oxide semiconductors will be described below.

[0140] Oxide semiconductors are divided into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors. As a non-single-crystal oxide semiconductor, CAAC-OS (C Axis Aligned) is used. Crystalline Oxide Semiconductor, Polycrystalline Oxide Semiconductor Examples include conductors, microcrystalline oxide semiconductors, and amorphous oxide semiconductors.

[0141] From another perspective, oxide semiconductors include amorphous oxide semiconductors and other crystalline oxide semiconductors. They can be divided into conductors and crystalline oxide semiconductors. Examples of crystalline oxide semiconductors include single-crystal oxide semiconductors and CAAC-O Examples include S, polycrystalline oxide semiconductors, and microcrystalline oxide semiconductors.

[0142] <caac-os> First, let's explain CAAC-OS. Note that CAAC-OS is referred to as CANC(C-Ax It can also be called an oxide semiconductor having (aligned nanocrystals). can.

[0143] CAAC-OS is an oxide semiconductor having multiple c-axis oriented crystalline portions (also called pellets). It is a type of conductor.

[0144] Transmission Electron Microscope (TEM) A composite analysis image of the bright-field image and diffraction pattern of CAAC-OS (high-frequency analysis) is obtained using the scope. Also called a resolving TEM image.) When observing this image, multiple pellets can be identified. In high-resolution TEM images, the boundaries between pellets, i.e., grain boundaries, are visible. It cannot be clearly confirmed that CAAC-OS occurs at the grain boundaries. This means that a decrease in electron mobility due to this is less likely to occur.

[0145] The following describes CAAC-OS as observed by TEM. Figure 10(A) shows, This shows a high-resolution TEM image of a cross-section of CAAC-OS observed from a direction approximately parallel to the sample surface. For observing high-resolution TEM images, spherical aberration correction is necessary. The Corrector function was used. High-resolution TEM images using spherical aberration correction were obtained. This is specifically called a Cs-corrected high-resolution TEM image. Acquisition of Cs-corrected high-resolution TEM images is, for example, done in Japan. This is performed using an atomic-resolution analytical electron microscope, such as the JEM-ARM200F, manufactured by this electronics company. It is possible.

[0146] Figure 10(B) shows a magnified Cs-corrected high-resolution TEM image of region (1) in Figure 10(A). Figure 10(B) shows that the metal atoms in the pellet are arranged in layers. The arrangement of metal atoms in each layer is such that the surface forming the CAAC-OS film (also called the surface to be formed) Alternatively, it reflects the irregularities of the upper surface and is parallel to the surface or upper surface of the CAAC-OS that is formed.

[0147] As shown in Figure 10(B), CAAC-OS has a characteristic atomic arrangement. Figure 10(C) The characteristic atomic arrangement is shown with auxiliary lines. Figures 10(B) and 10(C) Therefore, the size of each pellet is approximately 1 nm to 3 nm, and the pellets are It can be seen that the size of the gap caused by the tilt is about 0.8 nm. Therefore, Lett can also be called a nanocrystal (nc).

[0148] Here, based on the Cs-corrected high-resolution TEM image, the pellets of CAAC-OS on substrate 5120 are used. The arrangement of the To 5100 can be schematically represented as a structure like bricks or blocks stacked on top of each other. (See Figure 10(D).) The tilt between the pellets observed in Figure 10(C) The area where the condensation is occurring corresponds to region 5161 shown in Figure 10(D).

[0149] Furthermore, Figure 11(A) shows the Cs in the plane of CAAC-OS observed from a direction approximately perpendicular to the sample surface. Corrected high-resolution TEM images are shown. Regions (1), (2), and (3) in Figure 11(A). Magnified Cs-corrected high-resolution TEM images are shown in Figures 11(B), 11(C), and 11(B), respectively. As shown in 11(D). From Figures 11(B), 11(C), and 11(D), the pellets are It can be confirmed that metal atoms are arranged in a triangular, square, or hexagonal shape. However, However, no regularity is observed in the arrangement of metal atoms between different pellets.

[0150] Next, the CA was analyzed by X-ray diffraction (XRD). Let's discuss AC-OS. For example, CAAC-OS, which has an InGaZnO4 crystal. In contrast, when structural analysis is performed using the out-of-plane method, as shown in Figure 12(A)... In some cases, a peak may appear at a diffraction angle (2θ) near 31°. This peak is in InGaZ Since it is attributed to the (009) plane of the nO4 crystal, the CAAC-OS crystal is c-axis oriented. It can be confirmed that the c-axis is oriented in a direction substantially perpendicular to the surface to be formed or the upper surface.

[0151] In addition, in the structural analysis using the out-of-plane method of CAAC-OS, 2θ is 31°. In addition to the nearby peak, a peak may also appear when 2θ is near 36°. The adjacent peak indicates that some of the crystals in CAAC-OS do not have c-axis orientation. This indicates that the more preferable CAAC-OS is the structural solution by the out-of-plane method. Analysis revealed a peak around 31° for 2θ, but no peak around 36° for 2θ.

[0152] On the other hand, for CAAC-OS, X-rays are incident from a direction approximately perpendicular to the c-axis in an in-plan configuration. Structural analysis using the e method reveals a peak near 2θ = 56°. This peak corresponds to In It is attributed to the (110) plane of the GaZnO4 crystal. In the case of CAAC-OS, 2θ is 56 The sample is fixed in the vicinity of °, and the analysis is performed while rotating the sample around the normal vector of the sample surface as the axis (φ axis). Even after performing a φ scan, no clear peak appears, as shown in Figure 12(B). Furthermore, if it is a single-crystal oxide semiconductor of InGaZnO4, then fixing 2θ to around 56°, φs If this occurs, the crystal plane is assigned to the equivalent of the (110) plane, as shown in Figure 12(C). Six lines are observed. Therefore, structural analysis using XRD indicates that CAAC-OS is It can be confirmed that the orientation of the a-axis and b-axis is irregular.

[0153] Next, we will explain CAAC-OS analyzed by electron diffraction. For example, InGaZ For CAAC-OS having nO4 crystals, a probe with a diameter of 300 nm is placed parallel to the sample surface. When an electron beam is incident, a diffraction pattern like the one shown in Figure 13(A) (limited field transmission electron diffraction) is observed. Sometimes a pattern (also called a diffraction pattern) may appear. This diffraction pattern is indicative of InGaZnO4. The spot originates from the (009) plane of the crystal. Therefore, electron diffraction also reveals... The pellets contained in CAAC-OS have c-axis orientation, and the c-axis is approximately aligned with the surface to be formed or the upper surface. It can be seen that it is oriented in a vertical direction. On the other hand, for the same sample, the probe is oriented perpendicular to the sample surface. Figure 13(B) shows the diffraction pattern when an electron beam with a diameter of 300 nm is incident on the surface. Figure 13 (B) shows a ring-shaped diffraction pattern. Therefore, electron diffraction also shows that It can be seen that the a-axis and b-axis of the pellets contained in CAAC-OS do not have any orientation. Note that the first ring in Figure 13(B) is the (010) plane of the InGaZnO4 crystal. This is thought to be caused by the (100) surface, etc. Also, the second ring in Figure 13(B) is (110) This is thought to be caused by the surface, etc.

[0154] Furthermore, CAAC-OS is an oxide semiconductor with a low defect level density. Examples include defects caused by impurities and oxygen deficiencies. Therefore, CAA C-OS can also be described as an oxide semiconductor with a low impurity concentration. Also, CAAC-OS It can also be described as an oxide semiconductor with few oxygen vacancies.

[0155] Impurities contained in oxide semiconductors can act as carrier traps or carrier sources. In some cases, oxygen vacancies in oxide semiconductors can act as carrier traps, or water Capturing a primal can sometimes create a source of carriers.

[0156] Impurities are elements other than the main components of oxide semiconductors, such as hydrogen, carbon, silicon, and transition metals. There are elements, for example. For instance, oxygen is more abundant than the metallic elements that make up oxide semiconductors such as silicon. Elements with strong bonding forces can alter the atomic arrangement of oxide semiconductors by removing oxygen from them. It disrupts the crystallinity and causes a decrease in its properties. Also, heavy metals such as iron and nickel, argon, and nickel... Because carbon oxides and other elements have a large atomic radius (or molecular radius), they affect the atomic arrangement of oxide semiconductors. This disrupts the crystallinity and reduces its properties.

[0157] Furthermore, oxide semiconductors with a low defect level density (few oxygen vacancies) have a low carrier density. Such oxide semiconductors can be processed using high-purity intrinsic or substantially high-purity intrinsic acid. It is called a monoxide semiconductor. CAAC-OS has a low impurity concentration and a low defect level density. That is, It is likely to become a high-purity intrinsic or substantially high-purity intrinsic oxide semiconductor. Therefore, CAA Transistors using C-OS exhibit an electrical characteristic where the threshold voltage is negative (normally). Also called "on." ) It rarely becomes [unclear]. Also, high-purity intrinsic or substantially high-purity intrinsic acid. Ion semiconductors have fewer carrier traps. Carriers are trapped in the carrier traps of oxide semiconductors. The charged particles take a long time to release, behaving almost like fixed charges. Yes, there is. Therefore, transients using oxide semiconductors with high impurity concentrations and high defect level densities are used. The sta may have unstable electrical characteristics. On the other hand, the transistor using CAAC-OS This results in a transistor with minimal fluctuations in electrical characteristics and high reliability.

[0158] Furthermore, because CAAC-OS has a low defect level density, it is less susceptible to defects generated by light irradiation, etc. The rear is rarely captured by the defect level. Therefore, the tracer using CAAC-OS The radiator exhibits minimal changes in electrical properties due to irradiation with visible or ultraviolet light.

[0159] <Microcrystalline oxide semiconductor> Next, we will explain microcrystalline oxide semiconductors.

[0160] Microcrystalline oxide semiconductors are regions where crystalline parts can be observed in high-resolution TEM images. It has regions where a clear crystalline structure cannot be identified. It is contained in microcrystalline oxide semiconductors. The crystalline portion is between 1 nm and 100 nm in size, or between 1 nm and 10 nm in size. This is often the case. In particular, microcrystals between 1 nm and 10 nm, or between 1 nm and 3 nm. An oxide semiconductor having nanocrystals is called nc-OS (nanocrystalline It is called Oxide Semiconductor. nc-OS is, for example, high resolution. In TEM images, grain boundaries may not be clearly visible. Note that the nanocrystals are CAAC. -It may share the same origin as pellets in OS. Therefore, nc-O The crystalline portion of S is sometimes called a pellet.

[0161] nc-OS is used in minute regions (for example, regions between 1 nm and 10 nm, especially between 1 nm and 3 nm). The atomic arrangement has periodicity in the region of less than nm. In addition, nc-OS has different pellets. No regularity in crystal orientation is observed between the layers. Therefore, no orientation is observed throughout the entire film. Therefore, depending on the analysis method, nc-OS may be indistinguishable from amorphous oxide semiconductors. For example, an XRD device that uses X-rays with a larger diameter than pellets compared to nc-OS. When structural analysis is performed using this method, the out-of-plane method shows that the crystal planes are visible. No peak is detected. Also, for nc-OS, the probe diameter is larger than the pellet (e.g. For example, when electron diffraction (also called limited-field electron diffraction) is performed using an electron beam of 50 nm or more, A diffraction pattern resembling a halo pattern is observed for nc-OS. Nanobeam electron diffraction using an electron beam with a probe diameter close to or smaller than the pellet size. When this is done, a spot is observed. Also, when nanobeam electron diffraction is performed on nc-OS In some cases, a region of high brightness can be observed in a circular (ring-shaped) pattern. Furthermore, phosphorus Multiple spots may be observed within a circular area.

[0162] Thus, since there is no regularity in the crystal orientation between pellets (nanocrystals), nc- The OS has RANC (Random Aligned nanocrystals) Oxide semiconductors, or NANCs (Non-Aligned nanocrystals) It can also be called an oxide semiconductor having ).

[0163] nc-OS is an oxide semiconductor with higher orderliness than amorphous oxide semiconductors. Therefore, nc-OS has a lower defect level density than amorphous oxide semiconductors. However, nc-OS There is no regularity in crystal orientation between different pellets. Therefore, nc-OS is CA Compared to AC-OS, the defect level density is higher.

[0164] <Amorphous oxide semiconductor> Next, we will explain amorphous oxide semiconductors.

[0165] Amorphous oxide semiconductors are oxides in which the atomic arrangement in the film is irregular and which do not have crystalline regions. It is a semiconductor. One example is an oxide semiconductor that has an amorphous state, such as quartz.

[0166] In amorphous oxide semiconductors, crystalline regions cannot be observed in high-resolution TEM images.

[0167] When structural analysis of amorphous oxide semiconductors is performed using an XRD device, out-of-pl Analysis using the ANE method does not detect any peaks indicating crystal planes. Furthermore, amorphous oxide semiconductors... When electron diffraction is performed on a material, a halo pattern is observed. Furthermore, amorphous oxide semiconductors... In contrast, when nanobeam electron diffraction is performed, no spots are observed, and only a halo pattern is visible. It is measured.

[0168] Various views have been expressed regarding amorphous structures. For example, some argue that the atomic arrangement has absolutely no order. A structure that does not have a completely amorphous structure It is sometimes called a cture. Also, although it does not have long-range order, it does not have a nearest neighbor atom. When a structure exhibits order within the range of atoms or up to the second nearest neighbor atoms, it is called an amorphous structure. There are also those. Therefore, according to the strictest definition, an oxidation that has at least a slight order in its atomic arrangement. It is not possible to call a material semiconductor an amorphous oxide semiconductor. Furthermore, at least long-range order Oxide semiconductors having a crystalline portion cannot be called amorphous oxide semiconductors. Therefore, having a crystalline portion Therefore, for example, CAAC-OS and nc-OS are amorphous oxide semiconductors or It cannot be called a perfectly amorphous oxide semiconductor.

[0169] <Amorphous-like oxide semiconductor> Furthermore, oxide semiconductors may have a structure between nc-OS and amorphous oxide semiconductors. Such an oxide semiconductor having such a structure is called an amorphous-like oxide semiconductor (a-li ke OS:amorphous-like Oxide Semiconductor ) is called.

[0170] a-like OS exhibits porosity (also called voids) in high-resolution TEM images. In some cases, the crystalline region can be clearly identified in high-resolution TEM images. It has a region where the crystalline part cannot be identified, and a region where the crystalline part cannot be identified.

[0171] Because it has porosity, a-like OS has an unstable structure. Below, a-like To demonstrate that the OS has a less stable structure compared to CAAC-OS and nc-OS. This shows the structural changes caused by electron irradiation.

[0172] The samples to be irradiated with electrons are a-like OS (referred to as sample A) and nc-OS ( Prepare Sample B (referred to as Sample B) and CAAC-OS (referred to as Sample C). The sample is also an In-Ga-Zn oxide.

[0173] First, high-resolution cross-sectional TEM images are obtained for each sample. It can be seen that all of them have crystalline parts.

[0174] The determination of which part should be considered a single crystal can be made as follows. For example, The unit cell of an InGaZnO4 crystal has three In-O layers and a Ga-Zn-O layer. It is known to have a structure in which 6 layers, totaling 9 layers, are stacked in layers along the c-axis. The spacing between adjacent layers is approximately the same as the spacing between grid planes (also called the d value) of the (009) plane. Yes, and its value has been determined to be 0.29 nm from crystal structure analysis. Therefore, the lattice fringes Areas with a spacing of 0.28 nm or more and 0.30 nm or less are considered to be the crystalline regions of InGaZnO4. This can be done. Note that the lattice patterns correspond to the ab-plane of the InGaZnO4 crystal.

[0175] Figure 14 shows an example of investigating the average size of the crystalline regions (22 to 45 locations) in each sample. However, the length of the lattice fringes mentioned above is used as the size of the crystal portion. From Figure 14, a-lik It can be seen that the crystalline portion of eOS increases in proportion to the cumulative amount of electron irradiation. As shown in (1) in Figure 14, the initial TEM observation is approximately 1.2 nm. The crystal region (also called the initial nucleus), which was initially 4.2 × 10¹⁶ in size, changed when the cumulative irradiation dose reached 4.2 × 10¹⁶. 8 e - / nm 2 In this case, it can be seen that it has grown to a size of about 2.6 nm. On the other hand, nc-OS And CAAC-OS has a cumulative electron dose of 4.2 × 10⁻⁶ from the start of electron irradiation. 8 e - / nm 2 Within this range, it can be seen that there is no change in the size of the crystal portion. Specifically, Figure As shown in (2) and (3) of 14, regardless of the cumulative dose of electrons, nc-OS and The size of the crystalline portion of CAAC-OS is approximately 1.4 nm and 2.1 nm, respectively. It becomes clear that...

[0176] Thus, in a-like OS, crystalline growth can sometimes be observed upon electron irradiation. On the other hand, nc-OS and CAAC-OS show almost no crystal growth due to electron irradiation. It can be seen that it cannot be seen. That is, a-like OS is nc-OS and CAAC-O Compared to S, it is clear that it has an unstable structure.

[0177] Furthermore, because it has porosity, a-like OS is superior to nc-OS and CAAC-OS. It has a low-density structure. Specifically, the density of a-like OS is the same as that of a single crystal of the same composition. The density will be between 78.6% and 92.3%. Also, the density of nc-OS and CAAC - The density of OS is between 92.3% and 100% of the density of a single crystal of the same composition. Oxide semiconductors with a density of less than 78% are difficult to deposit into film.

[0178] For example, in an oxide semiconductor satisfying In:Ga:Zn=1:1:1 [atomic ratio], The density of single-crystal InGaZnO4 with a faceted crystal structure is 6.357 g / cm³. 3 That's how it is. For example, in an oxide semiconductor satisfying In:Ga:Zn=1:1:1 [atomic ratio] The density of a-like OS is 5.0 g / cm³. 3 More than 5.9g / cm 3 It will be less than. For example, in an oxide semiconductor satisfying In:Ga:Zn=1:1:1 [atomic ratio], The density of nc-OS and CAAC-OS is 5.9 g / cm³. 3 More than 6.3g / cm 3 It will be less than.

[0179] Note that single crystals with the same composition may not exist. In that case, crystals with different compositions in arbitrary proportions may be found. By combining single crystals, the density equivalent to that of a single crystal at a desired composition can be estimated. This is possible. The density corresponding to a single crystal of the desired composition can be obtained by combining single crystals of different compositions. The proportion can be estimated using a weighted average. However, the density should be as small as possible. It is preferable to estimate by combining different types of single crystals.

[0180] As described above, oxide semiconductors can take on various structures, each possessing a variety of properties. Oxide semiconductors include, for example, amorphous oxide semiconductors, a-like OS, and microcrystalline oxides. The film may be a multilayer film containing two or more types of semiconductors and CAAC-OS.

[0181] (Embodiment 2) In this embodiment, the transistor has a slightly different shape from the transistor shown in Embodiment 1. I will now explain how to make the Ta.

[0182] <Transistor 2> Figures 15(A), 16(A), 17(A), 18(A), 19(A), 20(A) Figures 21(A) and 21(A) are top views illustrating the method for fabricating a transistor. The diagram shows dashed lines F1-F2 and F3-F4, and the corresponding cross-sectional diagrams. Figures 15(B), 16(B), 17(B), 18(B), 19(B), and 20(B) And as shown in Figure 21(B).

[0183] First, prepare circuit board 500. Refer to the description for circuit board 400 for information on circuit board 500.

[0184] Next, a conductive film is deposited. The conductive film is deposited by sputtering, CVD, MBE, or This can be done using methods such as the PLD method and ALD method.

[0185] Next, a resist is formed on the conductor, and the conductor 513 is formed by processing using the resist. To accomplish.

[0186] Next, an insulator is deposited. The insulator can be deposited by sputtering, CVD, MBE, or This can be done using methods such as the PLD method and ALD method.

[0187] Next, from the top surface of the insulator toward the bottom surface, the edge is made parallel to the bottom surface of the substrate 500. By performing chipping, the conductor 513 is exposed and the insulator 503 is formed (Figure 15(A)). See also Figure 15(B). By forming the insulator 503 in this manner, the conductor The height of the top surface of 513 and the height of the top surface of the insulator 503 can be made to be approximately the same. Therefore, shape defects in subsequent processes can be suppressed.

[0188] Next, the insulator 502 is deposited (see Figures 16(A) and 16(B)). Insulator 50 For film deposition in step 2, sputtering, CVD, MBE, PLD, ALD, etc. are used. This can be done. Refer to the description for insulator 402 for insulator 502.

[0189] Next, semiconductor 536a is deposited. The semiconductor 536a is deposited using sputtering and CVD. This can be done using methods such as the MBE method, PLD method, or ALD method. Semiconductor 536a Refer to the description of the semiconductor that will become semiconductor 406a.

[0190] Next, by adding oxygen, excess oxygen may be introduced into semiconductor 536a. Addition is performed, for example, by ion implantation, with an acceleration voltage of 2kV to 10kV, and the dose Quantity 5 x 10 14 ions / cm 2 The above 1 x 10 17 ions / cm 2 If you do the following: good.

[0191] Next, fluorine may be added to semiconductor 536a. The order of adding fluorine to semiconductor 536a can be reversed.

[0192] Fluorine addition is performed, for example, by ion implantation, with an accelerating voltage of 1kV to 200kV. Preferably, the voltage should be between 5kV and 100kV, and the dose should be 5 × 10⁻¹⁰ 19 ions / cm 3 Below top 5×10 22 ions / cm 3 The following is preferably 1 × 10 20 ions / cm 3 The above 1 ×10 22 ions / cm 3 You can do it as follows:

[0193] Next, semiconductor 536b is deposited. The semiconductor 536b is deposited using sputtering and CVD. This can be done using methods such as the MBE method, PLD method, or ALD method. Semiconductor 536b For semiconductor 406b, refer to the description of the semiconductor. By performing the film formation and semiconductor 536b deposition in succession without exposure to the atmosphere, the film contains approximately This reduces the incorporation of impurities into the interface.

[0194] Next, it is preferable to perform a heat treatment. The heat treatment is preferably performed at a temperature of 250°C to 650°C. It is preferable to carry it out at a temperature of 450°C to 600°C, and more preferably at 520°C to 570°C. The heat treatment is performed in an inert gas atmosphere, or with an oxidizing gas at a concentration of 10 ppm or more, or 1% or more. The process should be carried out in an atmosphere containing 10% or more of the substance. Heat treatment may also be carried out under reduced pressure. Alternatively, The principle is to heat-treat the material in an inert gas atmosphere, and then use an oxidizing gas to replenish the desorbed oxygen. Heat treatment may be carried out in an atmosphere containing 0 ppm or more, 1% or more, or 10% or more. By this principle, the crystallinity of semiconductors 536a and 536b is increased, and hydrogen and water It can remove various impurities.

[0195] Next, fluorine may be added to semiconductors 536a and 536b. Heat treatment of semiconductor 536a and semiconductor 536b, and The order in which the fluorine is added can be reversed.

[0196] Fluorine addition is performed, for example, by ion implantation, with an accelerating voltage of 1kV to 200kV. Preferably, the voltage should be between 5kV and 100kV, and the dose should be 5 × 10⁻¹⁰ 19 ions / cm 3 Below top 5×10 22 ions / cm 3 The following is preferably 1 × 10 20 ions / cm 3 The above 1 ×10 22 ions / cm 3 You can do it as follows:

[0197] Next, a conductive film is deposited. The conductive film is deposited by sputtering, CVD, MBE, or This can be done using methods such as the PLD method and the ALD method. The conductor is conductor 416a and Refer to the description of the conductor that will become conductor 416b.

[0198] Next, a resist is formed on the conductive material, and the conductive material 516a is processed using the resist. This forms the conductive material 516b (see Figures 17(A) and 17(B)).

[0199] Next, fluorine may be added to semiconductors 536a and 536b. The addition of fluorine is This can be done using conductors 516a and 516b as masks. In semiconductors 536a and 536b, conductors 516a and 516b are Fluorine can be selectively added to areas that do not overlap.

[0200] Furthermore, by reducing the thickness of the conductors 516a and 516b, for example, half In the conductor 536a and semiconductor 536b, the conductor 516a and conductor 516b overlap Fluorine may also be added to the area to be covered. This will result in conductor 516a and conductor 51 Semiconductor 536a having different fluorine concentrations in the region overlapping with 6b and the region not overlapping with 6b. And semiconductor 536b can be formed. For example, semiconductor 536a and semiconductor 5 In 36b, the region that overlaps with the conductors 516a and 516b is the conductor 516 The fluorine concentration is lower in regions that do not overlap with a and conductor 516b.

[0201] Fluorine addition is performed, for example, by ion implantation, with an accelerating voltage of 1kV to 200kV. Preferably, the voltage should be between 5kV and 100kV, and the dose should be 5 × 10⁻¹⁰ 19 ions / cm 3 Below top 5×10 22 ions / cm 3 The following is preferably 1 × 10 20 ions / cm 3 The above 1 ×10 22 ions / cm 3 You can do it as follows:

[0202] Next, a resist and the like are formed on the semiconductor 536b, and the resist, conductor 516a and conductor The semiconductor 506b and semiconductor 506a are formed by processing using the electrode 516b (Figure 18). See (A) and Figure 18(B).

[0203] Furthermore, the formation of conductor 516a, conductor 516b, semiconductor 506a, and semiconductor 506b is Alternatively, after forming the conductive material, the process may be carried out by the method described below.

[0204] First, a resist is formed on a conductive material, and the resist is used for processing, resulting in a conductive material 516, semi-conductive material. The conductor 506b and semiconductor 506a are formed (see Figures 21(A) and 21(B)). ). At this time, semiconductors 506b and 506a are subjected to the removal of the resist and then the conductor Processing may also be done using 516.

[0205] Next, a resist or the like is formed on the conductive material 516, and the conductive material 51 is processed using the resist. Forms 6a and the conductor 516b (see Figures 18(A) and 18(B)).

[0206] Next, the semiconductor 536c is deposited. The semiconductor 536c is deposited using sputtering or CVD. This can be done using methods such as the MBE method, PLD method, or ALD method. Semiconductor 536c See the description for semiconductor 436c.

[0207] Next, the insulator 542 is deposited. The insulator 542 is deposited by sputtering, CVD, This can be done using methods such as MBE, PLD, or ALD. Insulator 542 is an insulator. Refer to the description of edge body 442.

[0208] Next, through the insulator 542, semiconductors 506a, 506b, and 536c Fluorine may be added. Note that semiconductors 506a, 506b and 536 It is not necessary to add fluorine to all of c; fluorine can be added to any one or two layers. It may be added. Also, fluorine may be added to the insulator 542.

[0209] Fluorine addition is performed, for example, by ion implantation, with an accelerating voltage of 1kV to 200kV. Preferably, the voltage should be between 5kV and 100kV, and the dose should be 5 × 10⁻¹⁰ 19 ions / cm 3 Below top 5×10 22 ions / cm 3 The following is preferably 1 × 10 20 ions / cm 3 The above 1 ×10 22 ions / cm 3 You can do it as follows:

[0210] Next, the conductive material 534 is deposited (see Figures 19(A) and 19(B)). Conductive material 53 For film deposition in step 4, sputtering, CVD, MBE, PLD, ALD, etc. are used. This can be done. For conductor 534, refer to the description for conductor 434.

[0211] Next, a resist or the like is formed on the conductive material 534, and the conductive material 50 is processed using the resist. 4 is formed. Also, the insulator 542 is processed using the resist or conductor 504, and A marginal body 512 is formed. Also, the resist, conductor 504 or insulator 542 is used to form a semi-semi The conductor 536c is processed to form the semiconductor 506c (see Figures 20(A) and 20(B)). (Illuminate.) Note that here, the semiconductor 506c, the insulator 512, and the conductor 504 are viewed from above. While we sometimes process them to achieve a similar shape, this is not the only shape we are allowed to achieve. Alternatively, the insulator 512 and the conductor 504 may be processed using a different resist. For example, After forming the edge 512, a conductive film that will become the conductive 504 may be deposited, or the conductive 50 After forming 4, a resist or the like may be formed separately on the insulator that will become the insulator 512. For example, the semiconductor 506c may be connected to an adjacent transistor or other component.

[0212] Next, an insulator may be deposited. The insulator can be deposited by sputtering, CVD, or MBE. This can be done using methods such as the PLD method or ALD method.

[0213] Examples of insulators include boron, carbon, nitrogen, oxygen, fluorine, magnesium, and aluminum. Um, silicon, phosphorus, chlorine, argon, gallium, germanium, yttrium, zirconium An insulator containing conium, lanthanum, neodymium, hafnium, or tantalum, in a single layer, Alternatively, it can be used in a laminated configuration. The insulator is preferably aluminum oxide, silicon nitride, Silicon nitride, gallium oxide, yttrium oxide, zirconium oxide, lanthanum oxide, acid Insulators containing neodymium oxide, hafnium oxide, or tantalum oxide, in single layers or multilayered Use it.

[0214] The insulator preferably functions as a barrier layer. The insulator may, for example, contain oxygen or It has the function of blocking hydrogen. Or, the insulator is, for example, insulator 502 Alternatively, it is preferable that the insulator 512 has a higher ability to block oxygen and / or hydrogen. It seems so.

[0215] By following the above steps, a transistor according to one aspect of the present invention can be manufactured.

[0216] As described above, by adding fluorine to the channel formation region of the semiconductor, It can compensate for oxygen deficiency. Furthermore, fluorine forms a stable bond, thus compensating for oxygen deficiency. To provide a transistor with stable and good electrical characteristics by compensating for this. It is possible.

[0217] As shown in Figure 20(B), the transistor has an s-channel structure. The electric field from the electric body 504 and the conductor 513 is transmitted to the side surface of the semiconductor 506b. This structure is less susceptible to interference from 6a and conductor 516b, etc.

[0218] Note that the conductive material 513 does not need to be formed (see Figure 22(A)). Also, the insulator 512 Alternatively, the semiconductor 506c may be in a shape that protrudes from the conductor 504 (see Figure 22(B)). Furthermore, it is not necessary to process the insulator 542 and semiconductor 536c (see Figure 22(C)). Furthermore, even if the width of the conductor 513 in the F1-F2 cross section is greater than that of the semiconductor 506b Good (see Figure 23(A)). Also, the conductor 513 and the conductor 504 are in contact through the opening. It is also possible to do so (see Figure 23(B)). Furthermore, it is not necessary to provide the conductor 504 (Figure 23 See (C). ).

[0219] (Embodiment 3) In this embodiment, a semiconductor device circuit using a transistor or the like according to one aspect of the present invention is shown. Let me explain an example.

[0220] <CMOSインバータ> The circuit diagram shown in Figure 24(A) is a p-channel type transistor 2200 and an n-channel type transistor. This is a so-called CMO (Continuously Multi-Motorized) configuration, where two Rangitar 2100s are connected in series, with each gate connected. This shows the configuration of an S-inverter. The n-channel transistor 2100 contains an oxide semiconductor It is preferable to use a transistor having a conductor. This allows for a CMOS inverter. This can reduce power consumption in the circuit.

[0221] <CMOSアナログスイッチ> Furthermore, the circuit diagram shown in Figure 24(B) is for transistors 2100 and 2200. This shows a configuration where the source and drain are connected. It can function as a so-called CMOS analog switch. n-channel transistor It is preferable to use a transistor having an oxide semiconductor in the ZISTA 2100.

[0222] <Structure of a semiconductor device 1> Figure 25 is a cross-sectional view of the semiconductor device corresponding to Figure 24(A). The semiconductor device shown in Figure 25 It has transistor 2200 and transistor 2100. Also, transistor 2100 is placed above transistor 2200. The example shown in Figure 20 uses a transistor, but the semiconductor according to one aspect of the present invention The body apparatus is not limited to this. For example, see Figures 6, 7, 8, 22 or Figure You may use transistors such as those shown in 23 as transistor 2100. Therefore, for transistor 2100, the description of the transistor mentioned above should be applied as appropriate. To drink.

[0223] The transistor 2200 shown in Figure 25 is a transistor that uses a semiconductor substrate 450. Transistor 2200 is located in region 472a of the semiconductor substrate 450 and in the semiconductor substrate 450 It has a region 472b, an insulator 462, and a conductor 454.

[0224] In transistor 2200, regions 472a and 472b are the source region and It functions as a drain region. In addition, insulator 462 functions as a gate insulator. It has. In addition, the conductor 454 has the function of a gate electrode. Therefore, it is conductive The resistance of the channel formation region can be controlled by the potential applied to body 454. The potential applied to the conductor 454 causes conduction between region 472a and region 472b. Non-conductivity can be controlled.

[0225] The semiconductor substrate 450 can be, for example, a single semiconductor substrate such as silicon or germanium, or Other materials include silicon carbide, silicon germanium, gallium arsenide, indium phosphide, and zinc oxide. A compound semiconductor substrate made of gallium oxide or the like may be used. Preferably, a semiconductor A single-crystal silicon substrate is used as substrate 450.

[0226] The semiconductor substrate 450 uses a semiconductor substrate having impurities that impart an n-type conductivity. Furthermore, as the semiconductor substrate 450, a semiconductor substrate having impurities that impart a p-type conductivity is used. It is acceptable to do so. In that case, the region that becomes transistor 2200 should be given an n-type conductivity. Alternatively, even if the semiconductor substrate 450 is i-type That's fine.

[0227] The upper surface of the semiconductor substrate 450 preferably has a (110) plane. This allows the This can improve the ON characteristics of the Rangista 2200.

[0228] Regions 472a and 472b are regions containing impurities that impart a p-type conductivity. In this way, transistor 2200 constitutes a p-channel transistor.

[0229] Furthermore, transistor 2200 is isolated from adjacent transistors by region 460, etc. Region 460 is an insulating region.

[0230] The semiconductor device shown in Figure 25 comprises an insulator 464, an insulator 466, an insulator 468, and a conductor. 480a, conductor 480b, conductor 480c, conductor 478a, conductor 478b And, conductor 478c, conductor 476a, conductor 476b, conductor 474a, conductive Body 474b, conductor 474c, conductor 496a, conductor 496b, conductor 496 c, conductor 496d, conductor 498a, conductor 498b, conductor 498c, It has a rim 490, an insulator 492, and an insulator 494.

[0231] Insulator 464 is placed on transistor 2200. Also, insulator 466 is insulator 4 It is placed on 64. Also, insulator 468 is placed on insulator 466. Also, insulator 4 90 is placed on the insulator 468. Also, transistor 2100 is placed on the insulator 490. Place them. Also, the insulator 492 is placed on the transistor 2100. Also, insulator 4 94 is placed on the insulator 492.

[0232] The insulator 464 has an opening that reaches region 472a and an opening that reaches region 472b, and a conductive It has an opening that reaches the body 454, and a conductive material 480a in the opening, and a conductive material A conductive material 480b or conductor 480c is embedded within it.

[0233] Furthermore, the insulator 466 has an opening that reaches the conductor 480a and an opening that reaches the conductor 480b. It has a section and an opening that reaches a conductor 480c. 478a, conductor 478b, or conductor 478c are embedded.

[0234] Furthermore, the insulator 468 has an opening that reaches the conductor 478b and an opening that reaches the conductor 478c. It has a section and a conductor 476a or a conductor 476b embedded in the openings, respectively. It's embedded.

[0235] Furthermore, the insulator 490 has an opening that overlaps with the channel formation region of the transistor 2100, and a guide It has an opening that reaches the electric body 476a and an opening that reaches the conductor 476b. A conductor 474a, conductor 474b, or conductor 474c is embedded in each opening. It is.

[0236] The conductor 474a may also function as the gate electrode of the transistor 2100. Alternatively, for example, by applying a constant potential to the conductor 474a, the transistor 210 You may also control electrical characteristics such as a threshold voltage of 0. Or, for example, conductor 474 a and the conductor 404 which functions as the gate electrode of transistor 2100 are electrically connected. It is acceptable to connect it. Doing so will increase the on-current of transistor 2100. This can be done. Also, because the punch-through phenomenon can be suppressed, transistor 210 The electrical characteristics in the saturation region at 0 can be stabilized.

[0237] Furthermore, the insulator 492 is located on either the source electrode or the drain electrode of the transistor 2100. An opening that passes through a certain conductor 516b and reaches conductor 474b, and transistor 2100 An opening that reaches the conductor 516a, which is the other of the source electrode or drain electrode, and An opening that reaches the conductor 504, which is the gate electrode of the ZISTA 2100, and an opening that reaches the conductor 474c It has an opening and a conductor 496a and a conductor 496b. , a conductor 496c or conductor 496d is embedded. However, each opening This may also occur via one of the components, such as transistor 2100.

[0238] Furthermore, the insulator 494 has an opening that reaches the conductor 496a, and the conductor 496b and the conductor It has an opening that reaches 496d and an opening that reaches the conductor 496c. Each of these has a conductor 498a, conductor 498b, or conductor 498c embedded in it. ru.

[0239] Insulator 464, insulator 466, insulator 468, insulator 490, insulator 492 and insulator Examples of 494 include boron, carbon, nitrogen, oxygen, fluorine, magnesium, and aluminum. Um, silicon, phosphorus, chlorine, argon, gallium, germanium, yttrium, zirconium An insulator containing conium, lanthanum, neodymium, hafnium, or tantalum, in a single layer, Alternatively, they can be used in a laminated configuration. For example, as the insulator 401, aluminum oxide, magnesium oxide, etc. Nesium, silicon oxide, silicon oxide nitride, silicon nitride oxide, silicon oxide, gas Yttrium, germanium oxide, yttrium oxide, zirconium oxide, lanthanum oxide, oxide Neodymium, hafnium oxide, or tantalum oxide can be used.

[0240] Insulator 464, insulator 466, insulator 468, insulator 490, insulator 492 or insulator One or more of 494 have an insulator that has the function of blocking impurities such as hydrogen and oxygen. It is preferable to have impurities such as hydrogen and oxygen near transistor 2100. By arranging an insulator that has a locking function, the electrical characteristics of transistor 2100 It can stabilize sexuality.

[0241] Examples of insulators that have the function of blocking impurities such as hydrogen and oxygen include boron. Element, carbon, nitrogen, oxygen, fluorine, magnesium, aluminum, silicon, phosphorus, chlorine, Argon, gallium, germanium, yttrium, zirconium, lanthanum, neodymium An insulator containing hafnium or tantalum may be used in a single layer or in a multilayer structure.

[0242] Conductor 480a, conductor 480b, conductor 480c, conductor 478a, conductor 478b, Conductor 478c, conductor 476a, conductor 476b, conductor 474a, conductor 474b, Conductor 474c, conductor 496a, conductor 496b, conductor 496c, conductor 496d, Examples of conductors 498a, 498b, and 498c include boron and nitrogen. Oxygen, fluorine, silicon, phosphorus, aluminum, titanium, chromium, manganese, cobalt Nickel, copper, zinc, gallium, yttrium, zirconium, molybdenum, ruthenium A single layer of a conductive material containing one or more elements: luminous, silver, indium, tin, tantalum, and tungsten. Alternatively, it can be used in a laminated configuration. For example, it can be an alloy or compound, such as aluminum. Conductors containing copper and titanium, conductors containing copper and manganese, indium Conductors containing tin and oxygen, conductors containing titanium and nitrogen, etc., may also be used.

[0243] Note that the semiconductor device shown in Figure 26 is the same as the semiconductor device shown in Figure 25, but with transistor 2200. The only difference is the structure. Therefore, the semiconductor device shown in Figure 26 is the same as the one shown in Figure 25. Refer to the description of the semiconductor device. Specifically, the semiconductor device shown in Figure 26 has two transistors. This indicates that transistor 200 is of the Fin type. The transistor 2200 is of the Fin type. This increases the effective channel width, thereby improving the on-characteristics of transistor 2200. This can be increased. Also, the contribution of the electric field of the gate electrode can be increased, This can improve the off-road characteristics of the Rangista 2200.

[0244] Furthermore, the semiconductor device shown in Figure 27 has the same transistor 2200 as the semiconductor device shown in Figure 25. The only difference is the structure. Therefore, the semiconductor device shown in Figure 27 is the same as the one shown in Figure 25. Refer to the description of the semiconductor device. Specifically, the semiconductor device shown in Figure 27 has two transistors. Figure 27 shows the case where 200 is provided on a semiconductor substrate 450 which is an SOI substrate. This shows a structure in which region 456 is separated from the semiconductor substrate 450 by an insulator 452. By using an SOI substrate as the conductive substrate 450, phenomena such as punch-through can be suppressed. This allows for an improvement in the off-peak characteristics of transistor 2200. The insulator 452 is formed by insulating a portion of the semiconductor substrate 450. Yes, it is possible. For example, silicon oxide can be used as the insulator 452.

[0245] The semiconductor device shown in Figures 25 to 27 uses a semiconductor substrate to produce a p-channel transistor. To fabricate this and then fabricate an n-channel transistor above it, the occupied area of ​​the element is reduced. This can be done. In other words, the integration density of semiconductor devices can be increased. Also, n-channel A p-channel transistor and a p-channel transistor were fabricated using the same semiconductor substrate. Compared to other methods, the process can be simplified, thus increasing the productivity of semiconductor devices. This can be done. Furthermore, the yield of semiconductor devices can be increased. Also, p-channel type Langista is used in the LDD (Lightly Doped Drain) area and shallow training. In some cases, complex processes such as n-channel structure and strain design can be omitted. Compared to fabricating transistors using semiconductor substrates, this method offers higher productivity and yield. It may be possible to do so.

[0246] <Storage device 1> A transistor according to one aspect of the present invention is used to retain stored data even when power is not supplied. Figure 28 shows an example of a semiconductor device (memory device) that can be stored and has no limit on the number of write cycles. This will be shown.

[0247] The semiconductor device shown in Figure 28(A) consists of a transistor 3200 using a first semiconductor and a second semiconductor It has a semiconductor transistor 3300 and a capacitive element 3400. The transistors mentioned above can be used as the Rangista 3300.

[0248] Transistor 3300 is preferably a transistor with a low off-current. Transistor 33 For example, 00 can use a transistor made of an oxide semiconductor. Due to the low off-current of the TA3300, it is possible to write to specific nodes of a semiconductor device over a long period of time. It is possible to retain the stored content. In other words, it does not require a refresh operation, or Because the refresh operation frequency can be made extremely low, low power consumption semiconductors It becomes a body device.

[0249] In Figure 28(A), the first wiring 3001 is electrically connected to the source of transistor 3200. The second wire 3002 is connected and electrically connected to the drain of transistor 3200. Furthermore, the third wire 3003 is electrically connected to one of the source and drain of transistor 3300. The fourth wire 3004 is connected to the gate of transistor 3300 and is electrically connected to the gate of transistor 3300. And the gate of transistor 3200, and the source of transistor 3300, The other end of the drain is electrically connected to one of the electrodes of the capacitive element 3400 and to the fifth wiring 30 05 is electrically connected to the other electrode of the capacitive element 3400.

[0250] The semiconductor device shown in Figure 28(A) is capable of maintaining the gate potential of transistor 3200. Having these characteristics, it is possible to write, hold, and read information as shown below. ru.

[0251] This section will explain how to write and retain information. First, the potential of the fourth wiring 3004 is set to the traction control. The potential is set so that transistor 3300 becomes conductive, and transistor 3300 becomes conductive. This causes the potential of the third wiring 3003 to be the gate of transistor 3200, and the capacitance It is supplied to node FG, which is electrically connected to one of the electrodes of the quantitative element 3400. That is, A predetermined charge is applied (written) to the gate of the ZISTA 3200. Here, different A charge that gives two potential levels (hereinafter referred to as low-level charge and high-level charge). One of the following is given. Then, the potential of the fourth wiring 3004 is set by the transistor The potential is set so that transistor 3300 becomes non-conductive, thereby causing transistor 3300 to become non-conductive. As a result, charge is retained at node FG.

[0252] Because the off-current of transistor 3300 is small, the charge at node FG is maintained over a long period of time. It is held.

[0253] Next, we will explain how to read the information. A predetermined potential (constant potential) is applied to the first wiring 3001. In this state, when an appropriate potential (readout potential) is applied to the fifth wiring 3005, the second wiring 3002 takes on a potential corresponding to the amount of charge held at node FG. This is the transistor. If 3200 is an n-channel type, then a high-level charge will be applied to the gate of transistor 3200. The apparent threshold voltage V when given th_H This is the transistor 3200 Apparent threshold voltage V when a low level charge is applied to the gate th_L Yo This is because it becomes lower. Here, the apparent threshold voltage is defined as the transistor 3200 This refers to the potential of the fifth wiring 3005 necessary to achieve a "conductive state". Then, set the potential of the fifth wiring 3005 to V th_H and V th_L By setting the potential V0 between these points, Therefore, the charge applied to node FG can be determined. For example, in writing, node FG If a high-level charge is applied, the potential of the fifth wiring 3005 will be V0(> V th_H ) In that case, transistor 3200 will be in a "conducting state". On the other hand, node FG If a low-level charge is applied, the potential of the fifth wiring 3005 is V0( <V th_L Even in this state, transistor 3200 remains in a "non-conductive state". By determining the potential of the second wiring 3002, the information held in node FG can be read. It can be released.

[0254] Furthermore, when memory cells are arranged in an array, the information of the desired memory cell is read. The data must be read. In order to avoid reading information from other memory cells, the node Regardless of the charge applied to FG, the potential at which transistor 3200 becomes "non-conductive" , in other words, V th_H A lower potential should be applied to the fifth wiring 3005. Or, no The potential at which transistor 3200 becomes "conductive" regardless of the charge applied to FG. , in other words, V th_L A higher potential should be applied to the fifth wiring 3005.

[0255] <Storage device 2> The semiconductor device shown in Figure 28(B) is different from the one in Figure 28(A) in that it does not have transistor 3200. This is different from the semiconductor device shown. In this case, it operates similarly to the semiconductor device shown in Figure 28(A). It allows for more efficient information writing and retention.

[0256] The information readout process in the semiconductor device shown in Figure 28(B) will be explained. When terminal 3300 becomes conductive, the floating third wiring 3003 and the capacitive element 3400 The two circuits become conductive, and charge is redistributed between the third wiring 3003 and the capacitive element 3400. As a result, the potential of the third wiring 3003 changes. The amount of change in the potential of the third wiring 3003 is the capacitance. The potential of one electrode of element 3400 (or the charge accumulated in the capacitive element 3400) They take on different values.

[0257] For example, let V be the potential of one electrode of the capacitive element 3400, C be the capacitance of the capacitive element 3400, and the third The capacitance component of wiring 3003 is CB, and the charge of the third wiring 3003 before redistribution is CB If the potential is VB0, then the potential of the third wiring 3003 after the charge has been redistributed is (CB × VB0 + C × V) / (CB + C). Therefore, the state of the memory cell is the capacity element If one of the electrodes of the child 3400 takes on two states, V1 and V0 (V1 > V0), then , the potential of the third wiring 3003 when the potential V1 is maintained (=(CB×VB0+C×V 1) / (CB+C)) is the potential of the third wiring 3003 when the potential V0 is maintained (= It can be seen that this is higher than (CB × VB0 + C × V0) / (CB + C)).

[0258] Then, by comparing the potential of the third wiring 3003 with a predetermined potential, the information is read out. It is possible.

[0259] In this case, the first semiconductor is applied to the drive circuit for driving the memory cell. Using a transistor, a second semiconductor was applied to the transistor 3300. The components should be stacked and arranged on top of the drive circuit.

[0260] The semiconductor device described above utilizes an oxide semiconductor transistor with a low off-current. This makes it possible to retain memory content over a long period of time. In other words, refresh This eliminates the need for refresh operations or makes it possible to significantly reduce the frequency of refresh operations. Therefore, it is possible to realize semiconductor devices with low power consumption. Also, in situations where there is no power supply... Even if the potential is fixed (however, it is preferable that the potential remains fixed), the memory will not be stored for a long period of time. It is possible to maintain the volume.

[0261] Furthermore, since this semiconductor device does not require high voltage for writing information, element degradation does not occur. It is difficult. For example, unlike conventional non-volatile memory, the concentration of electrons on the floating gate Because electrons are not drawn in or out from the floating gate, the insulator does not deteriorate. The problem does not arise. That is, the semiconductor device according to one aspect of the present invention is a conventional non-volatile memory The semiconductor device has no limit on the number of rewrite cycles, which is a problem, and its reliability has been dramatically improved. Furthermore, information is written depending on whether the transistor is in a conductive or non-conductive state. This allows for high-speed operation.

[0262] <Structure of a semiconductor device 2> Figure 29 is a cross-sectional view of the semiconductor device corresponding to Figure 28(A). Semiconductor device shown in Figure 29 It comprises a transistor 3200, a transistor 3300, and a capacitive element 3400. Furthermore, transistor 3300 and capacitive element 3400 are located above transistor 3200. It is placed in the following location. Note that transistor 3300 is the same as transistor 2100 mentioned above. Refer to the description below. Also, as transistor 3200, the transistor shown in Figure 25 Refer to the description of transistor 2200. Note that in Figure 25, transistor 2200 is p We have explained the case of a channel-type transistor, but transistor 3200 is an n-channel type transistor. A Nell-type transistor would also be acceptable.

[0263] The transistor 3200 shown in Figure 29 is a transistor that uses a semiconductor substrate 450. Transistor 3200 is located in region 472a of the semiconductor substrate 450 and in the semiconductor substrate 450 It has a region 472b, an insulator 462, and a conductor 454.

[0264] The semiconductor device shown in Figure 29 comprises an insulator 464, an insulator 466, an insulator 468, and a conductor. 480a, conductor 480b, conductor 480c, conductor 478a, conductor 478b And, conductor 478c, conductor 476a, conductor 476b, conductor 474a, conductive Body 474b, conductor 474c, conductor 496a, conductor 496b, conductor 496 c, conductor 496d, conductor 498a, conductor 498b, conductor 498c, conductor It has an electric body 498d, an insulator 490, an insulator 492, and an insulator 494.

[0265] Insulator 464 is placed on transistor 3200. Also, insulator 466 is insulator 4 It is placed on 64. Also, insulator 468 is placed on insulator 466. Also, insulator 4 90 is placed on the insulator 468. Also, transistor 3300 is placed on the insulator 490. Place them. Also, the insulator 492 is placed on the transistor 3300. Also, insulator 4 94 is placed on the insulator 492.

[0266] The insulator 464 has an opening that reaches region 472a and an opening that reaches region 472b, and a conductive It has an opening that reaches the body 454, and a conductive material 480a in the opening, and a conductive material A conductive material 480b or conductor 480c is embedded within it.

[0267] Furthermore, the insulator 466 has an opening that reaches the conductor 480a and an opening that reaches the conductor 480b. It has a section and an opening that reaches a conductor 480c. 478a, conductor 478b, or conductor 478c are embedded.

[0268] Furthermore, the insulator 468 has an opening that reaches the conductor 478b and an opening that reaches the conductor 478c. It has a section and a conductor 476a or a conductor 476b embedded in the openings, respectively. It's embedded.

[0269] Furthermore, the insulator 490 has an opening that overlaps with the channel formation region of the transistor 3300, and a conductor It has an opening that reaches the electric body 476a and an opening that reaches the conductor 476b. A conductor 474a, conductor 474b, or conductor 474c is embedded in each opening. It is.

[0270] The conductor 474a may also function as the bottom gate electrode of the transistor 3300. No. Or, for example, by applying a constant potential to the conductor 474a, a transistor can be formed. You may also control electrical characteristics such as the threshold voltage of 3300. Or, for example, a conductor 474a and the conductor 404, which is the top gate electrode of transistor 3300, are electrically connected. You can continue doing this. Doing so will increase the on-current of transistor 3300. This is possible. Furthermore, because the punch-through phenomenon can be suppressed, the transistor 3300 The electrical characteristics in the saturation region can be stabilized.

[0271] Furthermore, the insulator 492 is located on either the source electrode or the drain electrode of the transistor 3300. An opening that passes through a certain conductor 516b and reaches conductor 474b, and transistor 3300 The conductor 516a and the insulator 511, which are the other of the source electrode or drain electrode, are connected by a heavy An opening that reaches the conductive material 514 and the conductive material 5 which is the gate electrode of the transistor 3300 An opening reaching 04 and the other of the source electrode or drain electrode of transistor 3300 It has an opening that passes through a conductor 516a and reaches a conductor 474c. Each part contains a conductor 496a, conductor 496b, conductor 496c, or conductor 496 d is embedded. However, each opening is further occupied by transistor 3300, etc. It may be done through one of the components.

[0272] Furthermore, the insulator 494 has an opening that reaches the conductor 496a and an opening that reaches the conductor 496b. It has a section, an opening that reaches the conductor 496c, and an opening that reaches the conductor 496d. Furthermore, the openings are each fitted with a conductor 498a, conductor 498b, conductor 498c, or a conductor The 498d battery is embedded.

[0273] Insulator 464, insulator 466, insulator 468, insulator 490, insulator 492 or insulator One or more of 494 have an insulator that has the function of blocking impurities such as hydrogen and oxygen. It is preferable to have impurities such as hydrogen and oxygen near transistor 3300. By arranging an insulator that has a locking function, the electrical characteristics of transistor 3300 It can stabilize sexuality.

[0274] Examples of conductors 498d include boron, nitrogen, oxygen, fluorine, silicon, phosphorus, and aluminum. Titanium, chromium, manganese, cobalt, nickel, copper, zinc, gallium, t Thorium, zirconium, molybdenum, ruthenium, silver, indium, tin, tantalum A conductor containing one or more types of tungsten can be used in a single layer or in a multilayer structure. For example They may be alloys or compounds, including conductors containing aluminum, copper and titanium. Conductors containing copper and manganese, conductors containing indium, tin and oxygen, titanium And conductors containing nitrogen may also be used.

[0275] The source or drain of transistor 3200 is connected to conductor 480b and conductor 478b. , via conductor 476a, conductor 474b, and conductor 496c, transistor 33 It is electrically connected to the conductor 516b, which is either the source electrode or the drain electrode of 00. Furthermore, the conductor 454, which is the gate electrode of transistor 3200, is made of conductor 480c and Through the conductive body 478c, conductive body 476b, conductive body 474c, and conductive body 496d, The conductor 516a, which is the source electrode or the other drain electrode of the lampistor 3300, and electricity Connect to the target.

[0276] The capacitive element 3400 is connected to the source electrode or the other of the drain electrode of the transistor 3300. It has electrodes that are connected by gas, a conductor 514, and an insulator 511. 1 undergoes the same process as insulator 512, which functions as a gate insulator for transistor 3300. Since it can be formed in this way, productivity can be increased, which is preferable in some cases. Also, the conductor 51 As for 4, the same process as the conductor 504 which functions as the gate electrode of transistor 3300 Using layers formed through this process can be preferable in some cases, as it can increase productivity.

[0277] For other structural details, please refer to the descriptions in Figure 25 and other relevant documents as appropriate.

[0278] Note that the semiconductor device shown in Figure 30 is the same as the semiconductor device shown in Figure 29, but with transistor 3200. The only difference is the structure. Therefore, the semiconductor device shown in Figure 30 is the same as the one shown in Figure 29. Refer to the description of the semiconductor device. Specifically, the semiconductor device shown in Figure 30 has three transistors. This indicates that 200 is of the Fin type. Regarding transistor 3200, which is of the Fin type... For details, please refer to the description of transistor 2200 shown in Figure 26. Note that in Figure 26, We have explained the case where the transistor 2200 is a p-channel type transistor, but The STA3200 can be an n-channel transistor.

[0279] Furthermore, the semiconductor device shown in Figure 31 has transistor 3200 of the semiconductor device shown in Figure 29. The only difference is the structure. Therefore, the semiconductor device shown in Figure 31 is the same as the one shown in Figure 29. Refer to the description of the semiconductor device. Specifically, the semiconductor device shown in Figure 31 has three transistors. This shows the case where 200 is provided on a semiconductor substrate 450 which is an SOI substrate. The transistor 3200 provided on the semiconductor substrate 450 is shown in Figure 27. Refer to the description of transistor 2200. Note that in Figure 27, transistor 2200 is p We have explained the case of a channel-type transistor, but transistor 3200 is an n-channel type transistor. A Nell-type transistor would also be acceptable.

[0280] <Imaging device> The following describes an imaging device according to one aspect of the present invention.

[0281] Figure 32(A) is a plan view showing an example of an imaging device 200 according to one aspect of the present invention. The unit 200 includes a pixel unit 210, a peripheral circuit 260 for driving the pixel unit 210, and a peripheral circuit It has a path 270, a peripheral circuit 280, and a peripheral circuit 290. The pixel section 210 has p rows and q columns. It has multiple pixels 211 arranged in a matrix (where p and q are integers greater than or equal to 2). Peripheral circuits 260, 270, 280, and 290 are each multiple It has the function of connecting to a number of pixels 211 and supplying signals to drive multiple pixels 211. Furthermore, in this specification, peripheral circuits 260, 270, and 280 are used. The term "peripheral circuit" or "drive circuit" is sometimes used to refer to all of these components, including peripheral circuitry 290. For example, peripheral circuit 260 can be considered part of the peripheral circuitry.

[0282] Furthermore, it is preferable that the imaging device 200 has a light source 291. The light source 291 is a detection light P It can emit 1.

[0283] Furthermore, the peripheral circuits include at least logic circuits, switches, buffers, amplification circuits, or converters. It has one of the circuits. Furthermore, the peripheral circuits may be fabricated on the substrate forming the pixel section 210. Furthermore, semiconductor devices such as IC chips may be used in part or all of the peripheral circuits. The peripheral circuits are peripheral circuit 260, peripheral circuit 270, peripheral circuit 280 and peripheral circuit 290. You may omit one or more of the following:

[0284] Furthermore, as shown in Figure 32(B), in the pixel section 210 of the imaging device 200, Pixels 211 may be arranged at an angle. By arranging pixels 211 at an angle, the row direction and The pixel spacing (pitch) in the column direction can be shortened. This allows the imaging device 200 to This allows for a further improvement in the quality of the images being captured.

[0285] <Example of pixel configuration 1> The imaging device 200 has one pixel 211 which is composed of multiple sub-pixels 212, and each sub A filter (color filter) that transmits light in a specific wavelength range is combined with pixel 212. This allows us to obtain the information necessary to display color images.

[0286] Figure 33(A) is a plan view showing an example of pixels 211 for acquiring a color image. Pixel 211 shown in 33(A) is equipped with a color filter that transmits light in the red (R) wavelength band. The sub-pixel 212 (hereinafter also referred to as "sub-pixel 212R") emits light in the green (G) wavelength band. Sub-pixel 212 (hereinafter also referred to as "sub-pixel 212G") is provided with a color filter that transmits light. Sub-pixel 212 is provided with a color filter that transmits light in the wavelength bands of (u) and blue (B). It has (hereinafter also referred to as "sub-pixel 212B"). The sub-pixel 212 is a photosensor It can be made to work.

[0287] Sub-pixels 212 (sub-pixels 212R, 212G, and 212B) are connected to wiring 23 1. It is electrically connected to wires 247, 248, 249, and 250. Pixel 212R, sub-pixel 212G, and sub-pixel 212B are each connected by independent wiring 25 It is connected to 3. Also, in this specification, for example, the nth row (where n is an integer between 1 and p). Wirings 248 and 249 connected to pixel 211 of ) are respectively wired 248[n] And it is written as wiring 249[n]. Also, for example, the mth column (where m is an integer between 1 and q) The wiring 253 connected to pixel 211 is denoted as wiring 253[m]. Note that in Figure 33(A In this case, wiring 253 is connected to the sub-pixel 212R of the m-th pixel 211. Wiring 253[m]G connects to sub-pixel 212G, and sub-pixel 53[m]R, wiring 253[m]G, and sub-pixel The wiring 253 connected to element 212B is described as wiring 253[m]B. Sub-pixel 212 is It is electrically connected to the surrounding circuitry via the above wiring.

[0288] Furthermore, the imaging device 200 transmits light of the same wavelength band to adjacent pixels 211. The sub-pixels 212, each equipped with a filter, are electrically connected to each other via a switch. Figure 33(B) shows the sub-pixels 212 of the pixel 211 arranged in n rows and m columns, and the pixel 2 This shows an example of the connection of subpixels 212 of pixel 211, which is located in row n+1 and column m adjacent to pixel 11. In Figure 33(B), subpixels 212R are arranged in row n and column m, and subpixels are arranged in row n+1 and column m. The sub-pixels 212R are connected via switch 201. Also, arranged in n rows and m columns The sub-pixel 212G placed and the sub-pixel 212G arranged in row n+1 and column m are switched 202 They are connected via [a certain method]. Also, the subpixels 212B are located in n rows and m columns, and the subpixels are located in n+1 rows and m columns. The sub-pixel 212B located there is connected via switch 203.

[0289] Furthermore, the color filters used for sub-pixel 212 are limited to red (R), green (G), and blue (B). Color film that transmits cyan (C), yellow (Y), and magenta (M) light respectively. A LUTA may be used. A sub-pixel detects light of three different wavelength bands in one pixel 211. By adding 212, it is possible to acquire a full-color image.

[0290] Alternatively, color filters that transmit red (R), green (G), and blue (B) light, respectively, are provided. In addition to the sub-pixels 212 that have been cut off, a sub-pixel with a color filter that transmits yellow (Y) light is provided. A pixel 211 having pixel 212 may be used. Alternatively, cyan (C) and yellow (Y) may be used, respectively. In addition to sub-pixels 212 equipped with a color filter that transmits ) and magenta (M) light, A pixel 21 has a sub-pixel 212 that is provided with a color filter that transmits blue (B) light. 1 may be used. Sub-pixels 2 detect light of four different wavelength bands in one pixel 211. By adding 12, the color reproduction accuracy of the acquired image can be further improved.

[0291] Furthermore, for example, in Figure 33(A), sub-pixel 212 detects the red wavelength band, and the green wavelength The ratio of the number of sub-pixels 212 that detect the bandwidth and the sub-pixels 212 that detect the blue wavelength bandwidth ( The pixel ratio (or light-receiving area ratio) does not have to be 1:1:1. For example, the pixel ratio (light-receiving area ratio) Alternatively, a Bayer array with red:green:blue = 1:2:1 may be used. Or, the pixel ratio (received The light area ratio can also be set to red:green:blue = 1:6:1.

[0292] Note that while one sub-pixel 212 may be provided in pixel 211, two or more are preferable. By providing two or more sub-pixels 212 that detect the same wavelength band, redundancy is increased, and the imaging device This can improve the reliability of the 200 unit.

[0293] Furthermore, IR (Infrared) absorbs or reflects visible light and transmits infrared light. By using a filter, an imaging device 200 that detects infrared light can be realized.

[0294] Also, an ND (Neutral Density) filter (light-reducing filter) is used. This is because when a large amount of light is incident on a photoelectric conversion element (light-receiving element), the output saturation occurs. This can prevent this. By using a combination of ND filters with different light reduction amounts, the imaging device This allows for a wider dynamic range in the image.

[0295] In addition to the filter mentioned above, a lens may also be provided at pixel 211. Here, Figure 34 An example of the arrangement of pixels 211, filter 254, and lens 255 will be explained using a cross-sectional diagram. By providing the 255 element, the photoelectric conversion element can efficiently receive incident light. Specifically, as shown in Figure 34(A), a lens 255 and a filter 25 are formed on the pixel 211. 4 (filters 254R, 254G, and 254B), and pixel circuit 2 The structure can be configured to allow light 256 to be incident on the photoelectric conversion element 220 through 30, etc.

[0296] However, as shown in the area enclosed by the dashed line, a portion of the light 256 indicated by the arrow is connected to wiring 257. It may be partially blocked by something. Therefore, as shown in Figure 34(B), the photoelectric The lens 255 and filter 254 are placed on the side of the conversion element 220, and the photoelectric conversion element 220 A structure that efficiently receives light 256 is preferred. Light 256 is received from the photoelectric conversion element 220 side. By injecting light into the photoelectric conversion element 220, an imaging device 200 with high detection sensitivity is provided. It is possible.

[0297] As shown in Figure 34, the photoelectric conversion element 220 has a pn-type junction or a pin-type junction formed on it. Photoelectric conversion elements may also be used.

[0298] Furthermore, the photoelectric conversion element 220 uses a material that has the function of absorbing radiation and generating electric charge. It may be formed by absorbing radiation and generating an electric charge. Len, lead iodide, mercury iodide, gallium arsenide, cadmium telluride, cadmium zinc alloy These include:

[0299] For example, if selenium is used in the photoelectric conversion element 220, in addition to visible light, ultraviolet light, and infrared light, Photoelectric conversion element 2 having an optical absorption coefficient across a wide wavelength range, including X-rays and gamma rays. We can achieve 20.

[0300] Here, one pixel 211 of the imaging device 200 is, in addition to the sub-pixel 212 shown in Figure 33, Furthermore, it may have a sub-pixel 212 having a first filter.

[0301] <Example of pixel configuration 2> Below, we will discuss transistors using silicon and transistors using oxide semiconductors. An example of how pixels are constructed using this method will be explained.

[0302] Figures 35(A) and 35(B) are cross-sectional views of the elements constituting the imaging device. Figure 35(A) The imaging device shown has a silicon transistor 35 provided on a silicon substrate 300. 1. Transistor 35 using oxide semiconductors stacked on top of transistor 351 2 and transistor 353, and photodiode provided on silicon substrate 300 Includes 360 transistors and photodiodes 360. Each transistor and photodiode 360 ​​is plugged into various plugs 370. and has electrical connections with wiring 371. Also, the anode 3 of photodiode 360 61 has an electrical connection with the plug 370 via the low-resistance region 363.

[0303] The imaging device also includes a transistor 351 and a photodie provided on the silicon substrate 300. A layer 310 having an ore 360, and a layer 3 provided in contact with the layer 310 and having wiring 371 20 is provided in contact with layer 320 and has transistors 352 and 353. A layer 330, and a layer 330 provided in contact with the layer 330, having wiring 372 and wiring 373. It has 40.

[0304] In the example cross-sectional view in Figure 35(A), the transistor 35 is located on the silicon substrate 300. The configuration includes a photodiode 360 ​​with a light-receiving surface on the side opposite to the surface on which 1 is formed. This configuration ensures that the optical path is not affected by various transistors, wiring, etc. This allows for the formation of pixels with a high aperture ratio. The 360-degree light-receiving surface can also be the same as the surface on which transistor 351 is formed.

[0305] Furthermore, when constructing pixels using only transistors made of oxide semiconductors, layer 31 Layer 0 can be a layer containing a transistor made of oxide semiconductor. Alternatively, layer 310 can be omitted. In short, pixels may be constructed using only transistors made of oxide semiconductors.

[0306] Furthermore, when constructing pixels using only silicon transistors, layer 330 can be omitted. It can be omitted. An example of a cross-sectional view with layer 330 omitted is shown in Figure 35(B).

[0307] Furthermore, the silicon substrate 300 may be an SOI substrate. Replace with germanium, silicon germanium, silicon carbide, gallium arsenide, arsenide Using a substrate having gallium dioxide, indium phosphide, gallium nitride, or an organic semiconductor. It is possible to stay there.

[0308] Here, a layer 310 having a transistor 351 and a photodiode 360, and An insulator 380 is provided between the layer 330 having the diast 352 and the transistor 353. It can be kicked. However, the position of the insulator 380 is not limited.

[0309] The hydrogen in the insulator located near the channel formation region of transistor 351 is a silicon d This terminates the ring bond and improves the reliability of transistor 351. , hydrogen in an insulator provided near transistors 352 and 353 This is one of the factors that generate carriers in oxide semiconductors. Therefore, transistor 3 This can be a factor that reduces the reliability of transistors such as 52 and 353. So, a transistor using an oxide semiconductor on top of a silicon-based semiconductor transistor... When stacking the elements, an insulator 380 having the function of blocking hydrogen is placed between them. It is preferable to provide it. By confining hydrogen in the layer below the insulator 380, the transistor The reliability of 351 can be improved. Furthermore, from below the insulator 380, the insulator Because hydrogen diffusion to the layer above 380 can be suppressed, transistors 352 and 380 This can improve the reliability of devices such as the 353.

[0310] As the insulator 380, for example, an insulator having the function of blocking oxygen or hydrogen is used. Yes, they are.

[0311] Furthermore, in the cross-sectional view of Figure 35(A), the photodiode 360 ​​provided in layer 310 and layer The transistors provided at 330 can be formed to overlap with the pixels. This allows for an increase in the integration density, that is, an increase in the resolution of the imaging device.

[0312] Furthermore, as shown in Figures 36(A1) and 36(B1), part or all of the imaging device It may be curved. Figure 36(A1) shows the imaging device in the direction of the dashed line X1-X2 in the figure. This shows the curved state. Figure 36(A2) is the same as the dashed line X1-X in Figure 36(A1). This is a cross-sectional view of the area indicated in 2. Figure 36(A3) is the dashed line Y1- in Figure 36(A1). This is a cross-sectional view of the area indicated by Y2.

[0313] Figure 36(B1) shows the imaging device curved in the direction of the dashed line X3-X4 in the figure, and The diagram shows the curved state in the direction of the dashed line Y3-Y4. Figure 36(B2) is a diagram. This is a cross-sectional view of the area indicated by the dashed line X3-X4 in 36(B1). Figure 36(B3) is This is a cross-sectional view of the area indicated by the dashed line Y3-Y4 in Figure 36(B1).

[0314] By curving the imaging device, image field curvature and astigmatism can be reduced. This facilitates the optical design of lenses and other components used in combination with imaging devices. For example, This allows for a reduction in the number of lenses required for aberration correction, thus enabling miniaturization of electronic devices using imaging equipment. This allows for weight reduction and improves the quality of captured images. .

[0315] <cpu> The following describes a CPU that includes semiconductor devices such as the transistors and memory devices mentioned above. I will explain.

[0316] Figure 37 is a block diagram showing an example configuration of a CPU that uses the transistors described above in part. be.

[0317] The CPU shown in Figure 37 is an ALU1191 (ALU: Arithmet) mounted on board 1190. IC logic unit, arithmetic circuit, ALU controller 1192, instruction Timing decoder 1193, interrupt controller 1194, timing controller 1195, Register 1196, Register Controller 1197, Bus Interface 1 It has 198, a rewritable ROM 1199, and a ROM interface 1189. The substrate 1190 uses semiconductor substrates, SOI substrates, glass substrates, etc. ROM1 199 and the ROM interface 1189 may be provided on a separate chip. Of course, The CPU shown in Figure 37 is merely one example of a simplified configuration; an actual CPU is different. They have a wide variety of configurations depending on the application. For example, the CPU or arithmetic circuit shown in Figure 37. A configuration including this is considered one core, and there are multiple such cores, with each core operating in parallel. This configuration is also acceptable. Furthermore, the number of bits that the CPU can handle in its internal arithmetic circuits and data bus is: For example, it can be 8-bit, 16-bit, 32-bit, 64-bit, etc.

[0318] Instructions input to the CPU via the bus interface 1198 are instructions The signal is input to decoder 1193, decoded, and then processed by ALU controller 1192, interface Raptor controller 1194, register controller 1197, timing controller It is entered into 1195.

[0319] ALU controller 1192, interrupt controller 1194, register controller R1197 and timing controller 1195 control various commands based on the decoded instructions. To perform the operation. Specifically, the ALU controller 1192 controls the operation of the ALU 1191. It generates a signal for that purpose. Also, the interrupt controller 1194 is the CPU programmer. During execution, interrupt requests from external input / output devices and peripheral circuits are prioritized and masked. The state is judged and processed. The register controller 1197 adds register 1196 It generates a response and reads or writes to register 1196 depending on the CPU state.

[0320] Furthermore, the timing controller 1195 is connected to the ALU 1191 and the ALU controller 119 2. Instruction decoder 1193, interrupt controller 1194, and It generates signals to control the timing of the operation of the register controller 1197. For example, The timing controller 1195 generates an internal clock signal based on the reference clock signal. It is equipped with an internal clock generation unit that supplies the internal clock signal to the various circuits mentioned above.

[0321] In the CPU shown in Figure 37, a memory cell is located in register 1196. The transistors and memory devices mentioned above can be used as 1196 memory cells. ru.

[0322] In the CPU shown in Figure 37, the register controller 1197 receives information from the ALU 1191. Following the instructions, select the hold operation in register 1196. That is, register 1196 In the memory cell it possesses, data is held by a flip-flop, or capacitive elements Choose whether to retain data using flip-flops. Selecting to retain data using flip-flops is selected. If so, power voltage is supplied to the memory cell in register 1196. If data retention is selected for the quantitative element, data will be rewritten to the capacitive element. We can stop supplying power voltage to the memory cell in register 1196.

[0323] Figure 38 shows an example of a circuit diagram of a memory element 1200 that can be used as register 1196. The memory element 1200 has a circuit 1201 in which the stored data volatilizes when the power is cut off, and Circuit 1202 that prevents data from volatilizing when disconnected, switch 1203, switch 1204 It has a logic element 1206, a capacitive element 1207, and a circuit 1220 having a selection function. Circuit 1202 consists of a capacitive element 1208, a transistor 1209, and a transistor 12 It has 10 and. The memory element 1200 may also have a diode, a resistor, if necessary. It may further include other elements such as inductors.

[0324] Here, the memory device described above can be used in circuit 1202. Memory element 1200 When the power supply voltage to is cut off, the gate of transistor 1209 in circuit 1202 is G The configuration is such that ND (0V) or a potential that turns off transistor 1209 is continuously input. For example, the gate of transistor 1209 is grounded via a load such as a resistor. .

[0325] Switch 1203 uses a single-conductivity (e.g., n-channel) transistor 1213. The switch 1204 is configured to have a conductivity type opposite to that of a single-conductivity type (for example, a p-channel type). An example using transistor 1214 is shown. Here, the first terminal of switch 1203 The child corresponds to one of the source and drain of transistor 1213, and the second of switch 1203. The terminals correspond to the source and drain of transistor 1213, and switch 1203 is The control signal RD input to the gate of transistor 1213 controls the first terminal and the second terminal. Conductivity or non-conductivity between terminals (i.e., the conductive or non-conductive state of transistor 1213) The state is selected. The first terminal of switch 1204 is connected to the source and dot of transistor 1214. Corresponding to one side of the rain, the second terminal of switch 1204 is the source of transistor 1214. Corresponding to the other side of the drain, switch 1204 is input to the gate of transistor 1214. The control signal RD determines whether the first terminal and the second terminal are conductive or non-conductive (i.e., The conduction or non-conduction state of transistor 1214 is selected.

[0326] One of the sources and drains of transistor 1209 is connected to the pair of electrodes of capacitive element 1208. One side of this is electrically connected to the gate of transistor 1210. Here, the connection part Let the minute be node M2. One of the sources and drains of transistor 1210 is at a low power supply potential. It is electrically connected to a wire (e.g., a GND wire) that can supply power, and the other is a switch. The first terminal of 1203 (one of the source and drain of transistor 1213) is electrically connected. The second terminal of switch 1203 (source and drain of transistor 1213) On the other hand, the first terminal of switch 1204 (the source and drain of transistor 1214) is the first terminal of switch 1204. It is electrically connected to the second terminal of switch 1204 (the terminal of transistor 1214). The other end of the drain is electrically connected to wiring that can supply the power potential VDD. The second terminal of switch 1203 (the other terminal of the source and drain of transistor 1213) ) and the first terminal of switch 1204 (one of the source and drain of transistor 1214) ) and the input terminal of logic element 1206 and one of the pair of electrodes of capacitive element 1207, These are electrically connected. Here, the connection point is called node M1. A pair of capacitive elements 1207. The other electrode can be configured to receive a constant potential. For example, a low potential The system can be configured to receive either a source potential (such as GND) or a high power supply potential (such as VDD) as input. The other of the pair of electrodes of the capacitive element 1207 is a distribution capable of supplying a low power supply potential. It is electrically connected to a wire (for example, a GND wire). This configuration allows for a constant potential to be input. For example, a low power supply potential (such as GND). ) or a high power supply potential (VDD, etc.) can be input. Capacitive element 120 The other of the pair of electrodes (8) is connected to a wire capable of supplying a low power potential (e.g., GND). It is electrically connected to a wire.

[0327] Capacitive elements 1207 and 1208 are used to absorb parasitic capacitance from transistors and wiring. It was possible to omit it by actively using it.

[0328] The gate of transistor 1209 is input with the control signal WE. Switch 1203 and Switch 1204 is controlled by a control signal RD, which is different from the control signal WE, between the first and second terminals. A conductive or non-conductive state is selected between the terminals of one switch and the second terminal of the other switch. When there is conductivity between the terminals of one switch, there is no conductivity between the first and second terminals of the other switch. This is the result.

[0329] The source and drain of transistor 1209 are connected to the data held in circuit 1201. A signal corresponding to this is input. In Figure 38, the signal output from circuit 1201 is transmitted to the transistor. An example is shown where the source and drain of switch 1203 are input. The signal output from the second terminal (the other end of the source and drain of transistor 1213) is: The logic element 1206 inverts its logic value, resulting in an inverted signal, which is then transmitted via circuit 1220. This is then input to circuit 1201.

[0330] Note that in Figure 38, the second terminal of switch 1203 (source and terminal of transistor 1213) The signal output from the other side of Rain is routed through logic element 1206 and circuit 1220. An example of input to path 1201 is shown, but it is not limited to this. The second terminal of switch 1203 The signal output from (the other side of the source and drain of transistor 1213) is the inverse of the logic value. It may be input to circuit 1201 without being converted. For example, within circuit 1201, If there is a node that holds a signal that is the inverted logical value of the signal input from the input terminal The second terminal of switch 1203 (the other of the source and drain of transistor 1213) The signal output from this node can be input to the node in question.

[0331] Furthermore, in Figure 38, among the transistors used in the memory element 1200, Transistors other than TA1209 are made of a layer or substrate 119 made of a semiconductor other than an oxide semiconductor. A transistor can be formed where a channel is formed at 0. For example, a silicon film or It can be a transistor in which a channel is formed on a silicon substrate. Also, a memory element. All transistors used in the 1200 are transistors whose channels are formed from oxide semiconductors. It can also be a zista. Alternatively, the memory element 1200 may be a transistor other than the transistor 1209. However, it may also include a transistor whose channel is formed of an oxide semiconductor, and the remaining transistor The radiator has channels formed in a layer or substrate 1190 made of a semiconductor other than an oxide semiconductor. It can also be used as a transistor.

[0332] In Figure 38, circuit 1201 can be, for example, a flip-flop circuit. Furthermore, logic elements such as inverters and clocked inverters can be used as logic elements 1206. It is possible.

[0333] In a semiconductor device according to one aspect of the present invention, while the memory element 1200 is not supplied with a power supply voltage, The data stored in circuit 1201 is transferred to the capacitive element 1208 provided in circuit 1202. It can be held by.

[0334] Furthermore, transistors with channels formed in oxide semiconductors exhibit extremely low off-currents. For example, the off-current of a transistor in which a channel is formed in an oxide semiconductor is crystalline. It is significantly lower than the off-current of a transistor in which a channel is formed in silicon. By using the transistor as transistor 1209, the memory element 120 The signal held by the capacitive element 1208 is maintained for a long period of time even when no power supply voltage is supplied to 0. It drips. In this way, the memory element 1200 retains its stored contents (data) even when the power supply voltage is interrupted. It is possible to hold ).

[0335] Furthermore, by providing switches 1203 and 1204, pre-charge action Since it is a memory element characterized by performing an operation, after the power supply voltage is restored, the circuit 1201 This can shorten the time it takes to restore the original data.

[0336] Furthermore, in circuit 1202, the signal held by the capacitive element 1208 is transmitted to the transistor The signal is input to gate 1210. As a result, the power supply voltage to memory element 1200 is restored. After that, the signal held by the capacitive element 1208 is controlled by the state of transistor 1210 ( It can be converted to a conductive or non-conductive state and read from circuit 1202. Therefore, even if the potential corresponding to the signal held in the capacitive element 1208 fluctuates slightly, the original signal remains. It is possible to read the issue number accurately.

[0337] Such memory elements 1200 are stored in registers and cache memory of the processor. By using it in a storage device, it prevents the loss of data in the storage device due to a power supply interruption. This is possible. Furthermore, after the power supply voltage is restored, the system will quickly return to the state it was in before the power supply was interrupted. Therefore, the entire processor, or one of the components of the processor, This allows for power-off even for short periods in multiple logic circuits, thus reducing power consumption. It can be suppressed.

[0338] Although the memory element 1200 was explained as an example of being used in a CPU, the memory element 1200 is a DSP ( Digital Signal Processor), Custom LSI, PLD (Pr LSIs such as grammable logic devices, RF (Radio Frequency) It can also be applied to requency devices.

[0339] <Display device> In the following, a display device according to one aspect of the present invention will be described with reference to Figures 39 and 40. ru.

[0340] Display elements used in display devices include liquid crystal elements (also called liquid crystal display elements) and light-emitting elements. (Also called light-emitting display elements) can be used. Light-emitting elements respond to current or voltage. Therefore, elements whose brightness is controlled are included in that category, specifically inorganic EL (Electric Light). This includes luminescence (OLED), organic EL, etc. The following is an example of a display device. Display devices using EL elements (EL display devices) and display devices using liquid crystal elements (liquid crystal display devices) This section will explain the display device.

[0341] The display device described below comprises a panel in which the display elements are sealed, and a panel with This includes modules with ICs, controllers, and other components mounted on them.

[0342] Furthermore, the display devices described below refer to image display devices or light sources (including lighting devices). Also, a connector, such as an FPC, a module with TCP attached, and a preamplifier at the end of the TCP. A module or display element having a display substrate is directly connected to an IC (integrated circuit) using the COG method. All implemented modules are also included in the display device.

[0343] Figure 39 shows an example of an EL display device according to one aspect of the present invention. Figure 39(A) shows an EL display The circuit diagram of the device's pixels is shown. Figure 39(B) is a top view showing the entire EL display device. Furthermore, Figure 39(C) is a cross-section of MN, which corresponds to a portion of the dashed line MN in Figure 39(B). .

[0344] Figure 39(A) is an example of a circuit diagram of a pixel used in an EL display device.

[0345] In this specification, active elements (transistors, diodes, etc.), passive elements ( For all terminals of capacitive elements, resistive elements, etc., the destination of their connection is not specified. However, a person skilled in the art may be able to constitute one aspect of the invention. In other words, connection Even without specifying the destination, one aspect of the invention can be said to be clear. And the connection destination is specified. If the content is described in this specification, etc., then one aspect of the invention that does not specify the connection destination is described in this specification. In some cases, it can be determined that this is stated in the document or other documentation. In particular, multiple terminals are used as connection destinations. If multiple locations are anticipated, it is not necessary to limit the connection destination of the terminal to a specific location. Therefore, active elements (transistors, diodes, etc.), passive elements (capacitors, resistive elements) By specifying the connection destination for only some of the terminals that children (etc.) have, In some cases, it may be possible to constitute one aspect of clarity.

[0346] Furthermore, in this specification, etc., if a certain circuit is specified, then at least the connection destination is identified, and this applies to our business. If you are an expert, you may be able to identify the invention. Or, regarding a certain circuit, However, if the function is specified, a person skilled in the art may be able to specify the invention. In other words, if the function is specified, it can be said that one aspect of the invention is clear. It may be possible to determine that one aspect of the invention is described in this specification, etc. Therefore, even without specifying the function of a certain circuit, if the connection destination is specified, it constitutes an invention. It is disclosed as such and can constitute one aspect of the invention. Regarding a certain circuit, even if the connection destination is not specified, if the function is specified, it can be considered as one aspect of the invention. This has been disclosed and can constitute one aspect of the invention.

[0347] The EL display device shown in Figure 39(A) includes a switch element 743, a transistor 741, and It has a light-emitting element 742 and a light-emitting element 719.

[0348] Note that Figure 39(A), etc., is just one example of a circuit configuration, and further transistors can be added. It is possible to do so. Conversely, at each node in Figure 39(A), a transistor, a switch It is also possible to avoid adding passive components, etc.

[0349] The gate of transistor 741 is connected to one end of switch element 743 and one end of capacitive element 742. The electrodes are electrically connected. The source of transistor 741 is connected to the other electrode of capacitive element 742. It is electrically connected to and electrically connected to one electrode of the light-emitting element 719. The drain of 741 is supplied with the power supply potential VDD. The other end of the switch element 743 is connected to signal line 7 It is electrically connected to 44. A constant potential is applied to the other electrode of the light-emitting element 719. The constant potential is set to the ground potential (GND) or a potential lower than that.

[0350] It is preferable to use a transistor as the switching element 743. This allows for a reduction in pixel area, resulting in a high-resolution EL display device. As the switching element 743, a transistor was manufactured using the same process as transistor 741. Using transistor 74 can increase the productivity of EL display devices. 1 and / or, as the switching element 743, for example, the transistor described above can be applied. It is possible.

[0351] Figure 39(B) is a top view of the EL display device. The EL display device consists of a substrate 700 and a substrate 7 50, seal material 734, drive circuit 735, drive circuit 736, pixel 737, FP C732 and, have, the sealing material 734, pixel 737, drive circuit 735 and drive circuit It is positioned between circuit boards 700 and 750 so as to surround 736. Note that the drive circuit 735 Alternatively, the drive circuit 736 may be placed outside the sealant 734.

[0352] Figure 39(C) is a cross-sectional view of an EL display device corresponding to a portion of the dashed line MN in Figure 39(B). That is the case.

[0353] Figure 39(C) shows that transistor 741 is made of a conductive material 704a on substrate 700 and a conductive material Insulator 712a on body 704a, insulator 712b on insulator 712a, and insulator 712 semiconductors 706a and 706b located on b and overlapping with the conductor 704a, and semiconductor 70 Conductors 716a and 716b that are in contact with 6a and semiconductor 706b, and semiconductor 70 On 6b, on the conductor 716a, and the insulator 718a on the conductor 716b, and the insulator 718a The upper insulator 718b, the insulator 718c on the insulator 718b, and the insulator 718c The structure shows a semiconductor 706b overlapping with a conductor 714a. Note that transistor 7 Structure 41 is just one example, and may differ from the structure shown in Figure 39(C).

[0354] Therefore, in the transistor 741 shown in Figure 39(C), the conductor 704a is the gate Having the function of an electrode, insulators 712a and 712b function as gate insulators. It has a function, with conductor 716a functioning as a source electrode and conductor 716b being a drain It functions as an electrode, and insulators 718a, 718b, and 718c are The electrode has the function of an insulator, and the conductor 714a has the function of a gate electrode. Oh, semiconductors 706a and 706b may exhibit changes in their electrical properties when exposed to light. Therefore, the conductors 704a, 716a, 716b, and 714a It is preferable that one or more of them have light-shielding properties.

[0355] Note that the interface between insulator 718a and insulator 718b is shown with a dashed line; this represents the boundary between the two. This indicates that there may be cases where it is not clear. For example, consider insulator 718a and insulator 718b. Therefore, when using the same type of insulator, it may be impossible to distinguish between the two depending on the observation method.

[0356] Figure 39(C) shows a capacitance element 742, consisting of a conductor 704b on the substrate and a conductor 704b The upper insulator 712a, the insulator 712b on the insulator 712a, and the insulator 712b A conductor 716a overlapping with the conductor 704b, an insulator 718a on the conductor 716a, and an insulating Insulator 718b on body 718a, insulator 718c on insulator 718b, and insulator 718 It has a conductor 714b that is on c and overlaps with the conductor 716a, and the conductor 716a and the conductor In the overlapping region of the electric body 714b, a portion of the insulator 718a and insulator 718b is removed. This shows the structure.

[0357] In the capacitive element 742, the conductors 704b and 714b function as one of the electrodes. The conductor 716a functions as the other electrode.

[0358] Therefore, the capacitive element 742 is fabricated using a film common to the transistor 741. This is possible. Furthermore, it is preferable to use the same type of conductor for conductors 704a and 704b. In that case, the conductor 704a and the conductor 704b can be formed through the same process. It is possible. Furthermore, it is preferable to use the same type of conductor for conductors 714a and 714b. In this case, the conductor 714a and the conductor 714b can be formed through the same process. .

[0359] The capacitive element 742 shown in Figure 39(C) is a capacitive element with a large capacitance per unit area. Therefore, Figure 39(C) is an EL display device with high display quality. The capacitive element 742 shown is designed to thin the overlapping region of the conductors 716a and 714b. Therefore, although it has a structure in which a portion of the insulators 718a and 718b are removed, the present invention Capacitive elements relating to one embodiment are not limited thereto. For example, conductor 716a and In order to thin the overlapping region of the conductor 714b, a structure was created in which a portion of the insulator 718c was removed. It's okay to have it.

[0360] An insulator 720 is placed on the transistor 741 and the capacitive element 742. Here, The insulator 720 reaches the conductor 716a, which functions as the source electrode of the transistor 741. It may have an opening. A conductor 781 is placed on the insulator 720. 1 may be electrically connected to transistor 741 through an opening in the insulator 720.

[0361] A partition wall 784 having an opening that reaches the conductor 781 is placed on the conductor 781. A light-emitting layer 782 is positioned on the wall 784, in contact with the conductor 781 at the opening of the partition wall 784. A conductor 783 is placed on the light-emitting layer 782. Conductor 781, light-emitting layer 782 and The overlapping region of the conductor 783 becomes the light-emitting element 719.

[0362] Up to this point, we have explained examples of EL displays. Next, we will explain examples of liquid crystal displays. do.

[0363] Figure 40(A) is a circuit diagram showing an example of the pixel configuration of a liquid crystal display device. The pixels shown in Figure 40 are , a transistor 751, a capacitive element 752, and an element (liquid crystal) filled between a pair of electrodes. It has a crystal element 753.

[0364] In transistor 751, either the source or the drain is electrically connected to the signal line 755. The gate is electrically connected to scan line 754.

[0365] In the capacitive element 752, one electrode supplies electricity to the source and the other to the drain of the transistor 751. They are connected to each other, and the other electrode is electrically connected to a wiring that supplies a common potential.

[0366] In the liquid crystal element 753, one electrode supplies electricity to the source and the other to the drain of the transistor 751. They are connected to each other, and the other electrode is electrically connected to a wiring that supplies a common potential. The common potential applied to the wiring to which the other electrode of the capacitive element 752 described above is electrically connected, The common potential applied to the other electrode of the liquid crystal element 753 may be at a different potential.

[0367] Furthermore, the top view of the liquid crystal display device will be explained in the same way as that of the EL display device. Figure 39(B) Figure 40(B) shows a cross-sectional view of the liquid crystal display device corresponding to the dashed line MN. Furthermore, FPC732 is connected to wiring 733a via terminal 731. 3a is a conductor of the same type as either a conductor or semiconductor that constitutes transistor 751. Alternatively, semiconductors may be used.

[0368] Transistor 751 refers to the description of transistor 741. Also, capacitive elements Reference 752 refers to the description of the capacitive element 742. Note that Figure 40(B) is shown in Figure 39. The structure of the capacitance element 752 corresponding to the capacitance element 742 in (C) is shown, but it is not limited to this. stomach.

[0369] Furthermore, when an oxide semiconductor is used for the semiconductor of transistor 751, the off-current is extremely small. It can be made into a transistor. Therefore, the charge held in the capacitive element 752 It is less prone to cracking and can maintain the voltage applied to the liquid crystal element 753 over a long period of time. Therefore, when displaying videos or still images with little movement, transistor 751 is turned off. This eliminates the need for power to operate transistor 751, resulting in a low-power liquid crystal. It can be used as a crystal display device. Also, the occupied area of ​​the capacitive element 752 can be reduced, This makes it possible to provide liquid crystal display devices with a high aperture ratio or high-resolution liquid crystal display devices.

[0370] An insulator 721 is placed on the transistor 751 and the capacitive element 752. Here, The insulator 721 has an opening that reaches the transistor 751. On the insulator 721, The conductive body 791 is positioned. The conductive body 791 is connected to the transistor through the opening of the insulator 721. Connect electrically to 751.

[0371] An insulator 792, which functions as an alignment film, is placed on the conductor 791. A liquid crystal layer 793 is placed there. An insulator 7 that functions as an alignment layer is placed on top of the liquid crystal layer 793. 94 is placed. Spacer 795 is placed on insulator 794. Spacer 795 And a conductor 796 is placed on the insulator 794. On the conductor 796, a substrate 79 7 is placed.

[0372] The above-described structure provides a display device having a capacitive element with a small occupied area. It is possible to do so, or to provide a display device with high display quality. Or, high definition A display device can be provided.

[0373] For example, in this specification, etc., display element, display device having a display element, light-emitting element A light-emitting device, which is a device having a sub-element and a light-emitting element, can be used in various forms or It can have various elements. Display elements, display devices, light-emitting elements, or light-emitting devices are, for example, Light-emitting diodes (LEDs) come in various colors such as white, red, green, or blue. ting diode), transistor (a transistor that emits light in response to current), electron emission Output elements, liquid crystal elements, electronic ink, electrophoretic elements, grating light bulbs (GLV) Plasma displays (PDPs), MEMS (Micro-Electro-Mechanical Systems) Display elements using a stem, digital micromirror devices (DMD), DMS (digital micromirror devices) (Tal Micro-Shutter), IMOD (Interference Modulation) Elements, shutter-type MEMS display elements, optical interference type MEMS display elements, electro Wetting element, piezoelectric ceramic display, display using carbon nanotubes It has at least one element, etc. In addition to these, it is affected by electrical or magnetic forces The display medium may have properties such as contrast, brightness, reflectance, and transmittance that change.

[0374] An example of a display device using EL elements is an EL display. An example of a display device using this is a field emission display (FED). This is a SED type flat-panel display (SED: Surface-conduction E Examples include lectron-emitter displays. Examples of devices include liquid crystal displays (transmissive liquid crystal displays, semi-transmissive liquid crystal displays). (Play, reflective LCD display, direct-view LCD display, projection LCD display) Examples include electronic ink or electrophoretic elements, which are used in display devices. There are also transflective and reflective liquid crystal displays. In such cases, some or all of the pixel electrodes should function as reflective electrodes. For example, some or all of the pixel electrodes may be made of aluminum, silver, etc. This would be a good approach. Furthermore, in that case, a memory circuit such as an SRAM should be placed below the reflective electrode. This is also possible. This will further reduce power consumption.

[0375] Furthermore, when using LEDs, graphene or graphite is placed under the LED electrodes or nitride semiconductor. Threads may be placed. Graphene and graphite can be layered to form multilayer films. This is also good. In this way, by providing graphene or graphite, nitrides can be placed on top of it. Semiconductors, such as n-type GaN semiconductors having a crystalline structure, can be easily deposited as thin films. Furthermore, an LED can be constructed by providing a p-type GaN semiconductor with crystals on top of it. Yes, it is possible. Furthermore, between graphene or graphite and the crystalline n-type GaN semiconductor, An AlN layer may be provided. The GaN semiconductor in the LED is deposited by MOCVD. This is also acceptable. However, by providing graphene, the GaN semiconductor of the LED becomes spa It is also possible to deposit the film using the tarting method.

[0376] <Electronic equipment> A semiconductor device according to one aspect of the present invention comprises a display device, a personal computer, and a recording medium. Image playback devices (typically DVDs: Digital Versatile Discs) To be used in a device that has a display capable of playing back recording media such as the above and displaying the images thereof. This is possible. In addition, electronic devices that can use a semiconductor device according to one aspect of the present invention This includes mobile phones, game consoles including portable models, mobile data terminals, e-readers, and video cameras. , cameras such as digital still cameras, goggle-type displays (head-mounted displays) (Ray), navigation systems, sound reproduction devices (car audio, digital audio) Players, photocopiers, fax machines, printers, multifunction printers, ATMs Examples include ATMs and vending machines. Specific examples of these electronic devices are shown in Figure 41. vinegar.

[0377] Figure 41(A) shows a portable game console, consisting of a casing 901, casing 902, display unit 903, and display unit. 904, Microphone 905, Speaker 906, Control Keys 907, Stylus 908 It has the following features. The portable game console shown in Figure 41(A) has two display units 903 and a display unit. Although it has part 904, the number of display units that a portable game console has is not limited to this. .

[0378] Figure 41(B) shows a portable data terminal, comprising a first housing 911, a second housing 912, and a first display unit 9 13. It has a second display unit 914, a connection unit 915, an operation key 916, etc. First display unit 913 The first housing 911 is provided, and the second display unit 914 is provided in the second housing 912. Furthermore, the first housing 911 and the second housing 912 are connected by a connecting part 915. The angle between the first housing 911 and the second housing 912 can be changed by the connecting part 915. The video in the first display unit 913 is connected to the first housing 911 and the second housing 9 in the connection unit 915. The configuration may be such that it switches according to the angle between 12 and 12. Also, the first display unit 913 and a display in which at least one of the second display unit 914 is provided with a function as a position input device. A display device may be used. Note that the function as a position input device is provided by the display device. It can be added by providing a control panel. Alternatively, the function as a position input device can be... By installing a photoelectric conversion element, also called a photosensor, in the pixel section of the display device, additional features can be added. It is possible.

[0379] Figure 41(C) shows a notebook personal computer, comprising a casing 921, a display unit 922, and a keyboard. It includes a board 923, a pointing device 924, and the like.

[0380] Figure 41(D) shows an electric refrigerator-freezer, consisting of a casing 931, a refrigerator door 932, and a freezer door 93 It has a third-class rating.

[0381] Figure 41(E) shows a video camera, comprising a first housing 941, a second housing 942, a display unit 943, It has an operation key 944, a lens 945, a connecting part 946, etc. Operation key 944 and lens 945 is provided in the first housing 941, and the display unit 943 is provided in the second housing 942. And the first housing 941 and the second housing 942 are connected by a connecting part 946. The angle between the first housing 941 and the second housing 942 can be changed by the connecting part 946. The video on the display unit 943 is connected to the first housing 941 and the second housing 94 in the connection unit 946. The configuration may also be configured to switch according to the angle between 2 and 3.

[0382] Figure 41(F) is an automobile, consisting of a body 951, wheels 952, dashboard 953, and lights. It has 954, etc.

[0383] As described above, one aspect of the present invention has been explained in this embodiment. However, the present invention One aspect is not limited to these. For example, a semiconductor such as semiconductor 406b contains fluorine. The above is just one example; it is not limited to this. In some cases, semiconductors such as 406b may be used. The semiconductor may contain elements other than fluorine. Or, in some cases, semiconductor 406 Semiconductors such as b do not necessarily need to contain fluorine. [Examples]

[0384] In this example, fluorine was added to an oxide semiconductor film, and the fluorine concentration in the oxide semiconductor film was investigated. I will explain the results.

[0385] The sample was prepared by forming a 100 nm thick silicon oxide on a silicon substrate using a thermal oxidation method, and Afterwards, as an oxide semiconductor film, In-Ga-Zn-O (atomic ratio In:Ga:Zn=1:1 1) Using a target-based sputtering method, the IGZO film is made to a thickness of 100 nm. It was formed and manufactured.

[0386] The prepared sample was subjected to ion implantation, resulting in a value of 1.0 × 10⁻⁶. 15 ions / cm 2 and 1 .0 × 10 16 ions / cm 2 Fluoride ions at this dose ( 19 F + ) was added. The acceleration voltage was set to 20kV. The amount of fluorine added in the depth direction at this time was determined by SIMS. The results of the investigation are shown in Figure 42.

[0387] As shown in Figure 42, the result of fluorine is 1.0 × 10 15 ions / cm 2 If added, IG 3.0 × 10 on the ZO film 20 atoms / cm 3 It was found to be included to a certain extent. Also, The base is 1.0 × 10 16 ions / cm 2 When added, the IGZO film contains 3.0 × 10 21 a toms / cm 3 It was found to be included to some extent. [Examples]

[0388] In this example, fluorine was added to an oxide semiconductor film, and the sheet resistance of the oxide semiconductor film was investigated. I will explain the results.

[0389] The sample consists of an oxide semiconductor film made of In-Ga-Zn-O (atomic ratio In:G) on a quartz substrate. By sputtering using a target (a:Zn=1:1:1), the IGZO film was 1 It was fabricated by forming it to a thickness of 00 nm.

[0390] The prepared sample was subjected to ion implantation, resulting in a value of 1.0 × 10⁻⁶. 14 ions / cm 2 , 1.0 ×10 15 ions / cm 2 and 1.0 × 10 16 ions / cm 2 With this dose elementary ions ( 19 F + ) was added. The acceleration voltage was set to 20kV. Figure 43 shows the results of measuring the sheet resistance of the prepared sample. The upper limit of measurement is 1 × 10⁻⁶. 6 It is Ω / □.

[0391] As shown in Figure 43, the sheet resistance increases as more fluorine is added to the IGZO film. This was confirmed. Also, fluorine was 1.0 × 10 16 ions / cm 2 If added, IG The sheet resistance of the ZO film is 1 × 10⁻⁶. 6 The value was greater than Ω / □. From this, IGZO Adding fluorine to the film reduces the carrier concentration of the IGZO film, bringing it closer to a type i semiconductor. That's what I found out. [Examples]

[0392] In this embodiment, fluorine is added to the oxide semiconductor film, and defects in the oxide semiconductor film are detected by ESR. I will now explain the results of the investigation.

[0393] The sample consists of an oxide semiconductor film made of In-Ga-Zn-O (atomic ratio In:G) on a quartz substrate. By sputtering using a target (a:Zn=1:1:1), the IGZO film was 1 It was fabricated by forming it to a thickness of 00 nm.

[0394] The prepared sample was subjected to ion implantation, resulting in a value of 1.0 × 10⁻⁶. 14 ions / cm 2 , 1.0 ×10 15 ions / cm 2 or 1.0 × 10 16 ions / cm 2 With this dose elementary ions ( 19 F + ) was added. The acceleration voltage was set to 20kV. Figure 44 shows the results of ESR measurements performed on the prepared samples.

[0395] Figure 44(A) shows the ESR spectrum. From the results shown in Figure 44(A), the IGZO film... It was found that the more fluorine is added, the smaller the signal becomes around a g value of 1.93. Furthermore, Figure 44(B) compares the spin densities of signals where the g-value is around 1.93. The results are shown below. From Figure 44(B), the more fluorine is added to the IGZO film, the higher the g value becomes (1.93). It was found that the spin density of the signals observed in the vicinity was low.

[0396] In IGZO films, signals observed with a g value of around 1.93 are due to oxygen deficiency. Therefore, by adding fluorine to the IGZO film, the oxygen deficiency in the IGZO film is eliminated. It was found that this can be reduced. [Explanation of symbols]

[0397] 100 transistors 200 Imaging device 201 Switch 202 Switch 203 Switch 210 pixel section 211 pixels 212 subpixels 212B subpixels 212G sub-pixels 212R sub-pixels 220 Photoelectric conversion element 230-pixel circuit 231 Wiring 247 Wiring 248 Wiring 249 Wiring 250 Wiring 253 Wiring 254 filters 254B filter 254G filter 254R filter 255 lens 256 light 257 Wiring 260 Peripheral Circuits 270 Peripheral Circuits 280 Peripheral Circuits 290 Peripheral Circuits 291 Light source 300 silicon substrates 310 layers 320 layers 330 layers 340 layers 351 transistors 352 transistors 353 transistors 360 Photodiodes 361 Anodes 363 Low resistance region 370 plug 371 Wiring 372 Wiring 373 Wiring 380 Insulator 400 circuit boards 401 Insulator 402 Insulator 404 Conductors 406a Semiconductor 406b Semiconductor 406c semiconductor 412 Insulator 413 Conductors 416a Conductor 416b Conductor 434 Conductors 436c semiconductor 442 Insulator 450 Semiconductor substrates 452 Insulator 454 Conductors 456 areas 460 areas 462 Insulator 464 Insulator 466 Insulator 468 Insulator 472a area 472b area 474a Conductor 474b Conductor 474c conductor 476a Conductor 476b Conductor 478a Conductor 478b Conductor 478c Conductor 480a Conductor 480b Conductor 480c conductor 490 Insulator 492 Insulator 494 Insulator 496a Conductor 496b Conductor 496c conductor 496d Conductor 498a Conductor 498b Conductor 498c conductor 498d Conductor 500 circuit boards 502 Insulator 503 Insulator 504 Conductors 506a Semiconductor 506b Semiconductor 506c semiconductor 511 Insulator 512 Insulator 513 Conductors 514 Conductors 516 Conductors 516a Conductor 516b Conductor 534 Conductors 536a Semiconductor 536b Semiconductor 536c semiconductor 542 Insulator 700 circuit boards 704a Conductor 704b Conductor 706a Semiconductor 706b Semiconductor 712a Insulator 712b Insulator 714a Conductor 714b Conductor 716a Conductor 716b Conductor 718a Insulator 718b Insulator 718c insulator 719 Light-emitting element 720 Insulator 721 Insulator 731 terminal 732 FPC 733a Wiring 734 Sealant 735 Drive Circuit 736 Drive Circuit 737 pixels 741 transistors 742 Capacitive elements 743 Switching element 744 signal line 750 circuit boards 751 transistors 752 Capacitive element 753 Liquid crystal elements 754 scan lines 755 signal line 781 Conductors 782 Emitting layer 783 Conductors 784 Bulkhead 791 Conductors 792 Insulator 793 Liquid crystal layer 794 Insulator 795 Spacer 796 Conductors 797 circuit board 901 cabinet 902 cabinet 903 Display section 904 Display section 905 Microphone 906 Speakers 907 Operation Keys 908 Stylus 911 cabinet 912 cabinet 913 Display section 914 Display section 915 Connection part 916 Operation Keys 921 cabinet 922 Display section 923 Keyboard 924 Pointing Devices 931 cabinet 932 Refrigerator door 933 Freezer door 941 cabinet 942 cabinets 943 Display section 944 Operation Keys 945 lens 946 Connection part 951 Body 952 wheels 953 Dashboard 954 Light 1189 ROM Interface 1190 circuit board 1191 ALU 1192 ALU Controller 1193 Instruction Decoder 1194 Interrupt Controller 1195 Timing Controller 1196 Register 1197 Register Controller 1198 Bus Interface 1199 ROM 1200 memory elements 1201 Circuit 1202 Circuit 1203 Switch 1204 Switch 1206 Logic Element 1207 Capacitive element 1208 Capacitive element 1209 Transistors 1210 Transistors 1213 Transistor 1214 Transistors 1220 Circuit 2100 transistors 2200 transistors 3001 Wiring 3002 Wiring 3003 Wiring 3004 Wiring 3005 Wiring 3200 transistors 3300 transistors 3400 Capacitive element 5100 pellets 5120 circuit board 5161 area< / cpu>

Claims

[Claim 1] It comprises a gate electrode, a gate insulator, and an oxide semiconductor, The aforementioned oxide semiconductor is characterized by having fluorine in the channel-forming region.

Images