Semiconductor Devices

Abstract

To provide a semiconductor device with a high numerical aperture and a semiconductor device with a low power consumption, and provide a manufacturing method of them.SOLUTION: In a semiconductor device, a transistor 150a includes: an oxide semiconductor layer 103a provided onto a substrate 100 having an insulation front surface; a gate insulation film 104 covering the oxide semiconductor layer; a gate wiring containing a gate electrode 109a in which a first conductive layer and a second conductive layer provided onto the gate insulation film are laminated in this order; an insulation film 112 covering the gate wiring that contains the oxide semiconductor layer and the gate electrode; and a source wiring that is provided onto the insulation film, is electrically connected with the oxide semiconductor layer, and contains source electrodes 117a and 117b in which a third conductive layer and a fourth conductive layer are laminated in this order.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] A thin film transistor (hereinafter referred to as TFT) using an oxide semiconductor film in the channel formation region The present invention relates to a semiconductor device having a circuit configured therein and a manufacturing method thereof. The components include electro-optical devices, such as LEDs, and light-emitting display devices with organic light-emitting elements. Regarding electronic devices. [Background technology]

[0002] As typified by liquid crystal display devices, thin film transistors formed on flat plates such as glass substrates are , amorphous silicon, and polycrystalline silicon. Thin film transistors using silicon have low field effect mobility, but are suitable for enlarging the area of ​​glass substrates. On the other hand, thin film transistors using crystalline silicon have high field effect mobility. However, a crystallization process such as laser annealing is required, and enlarging the glass substrate is essential. However, it has the characteristic of not being adaptable.

[0003] In response to this, thin film transistors are being fabricated using oxide semiconductors, and they are being used in electronic devices and optical devices. For example, zinc oxide and In-G Thin film transistors were fabricated using a-Zn-O oxide semiconductors and used as switches for image display devices. The technology used for the gate element is disclosed in Patent Document 1 and Patent Document 2. By using a light-transmitting electrode for the gate electrode, source electrode, or drain electrode, Techniques for improving the rate of speech are being studied (Patent Documents 3 and 4). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-123861 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-096055 [Patent Document 3] Japanese Patent Application Laid-Open No. 2007-123700 [Patent Document 4] Japanese Patent Application Laid-Open No. 2007-81362 Summary of the Invention [Problem to be solved by the invention]

[0005] Normally, the wiring that connects elements, for example, transistors, is The conductive layer that constitutes the electrode, source electrode, or drain electrode is stretched as it is, and the same island (i Therefore, the gate of a transistor is connected to the gate of another transistor. The wiring that connects the gate electrode and the transistor (called the gate wiring) has the same layer structure and the same It is made of the same material and connects the source of one transistor to the source of another. The wiring (called source wiring) is made of the same layer structure and material as the source electrode of the transistor. Therefore, the gate electrode and the source or drain electrode When the electrode is formed using a light-transmitting material, the gate wiring and the source wiring are The gate electrode and the source or drain electrode are formed using a light-transmitting material. This will be accomplished.

[0006] However, usually, a material having optical transparency, such as indium tin oxide, indium Zinc oxide, indium tin zinc oxide, etc. are materials having light blocking and reflecting properties, e.g. , compared to aluminum, molybdenum, titanium, tungsten, neodymium, copper, silver, etc. Therefore, when a wiring is formed using a light-transmitting material, the wiring resistance is low. For example, when manufacturing a large display device, the wiring becomes long, and the wiring When the line resistance becomes very high and the wiring resistance becomes high, the waveform of the signal propagating through the wiring becomes unstable. This causes a blockage, and the voltage drop across the wiring resistance reduces the supplied voltage. It becomes difficult to supply accurate voltage and current, and normal display and operation cannot be achieved. It becomes difficult.

[0007] In addition, from the perspective of display performance, pixels are required to have large capacitance elements and a high aperture ratio. Each pixel has a high aperture ratio, which improves light utilization efficiency and reduces the energy consumption of the display device. In recent years, pixel size has become smaller, allowing for higher resolution images. The miniaturization of pixel size requires the size of the transistors and wiring that each pixel occupies. The pixel aperture ratio is reduced as the pixel area increases. To obtain a high aperture ratio for a pixel, it is necessary to efficiently lay out the circuit elements required for the pixel circuit configuration. It is essential to

[0008] In view of the above problems, an object of the present invention is to provide a semiconductor device with a high aperture ratio and a manufacturing method thereof. Another object of the present invention is to provide a semiconductor device with low power consumption or a manufacturing method thereof. It is considered one of the targets. [Means for solving the problem]

[0009] An example of the disclosed invention is a semiconductor device including an oxide semiconductor layer provided over a substrate having an insulating surface and an oxide semiconductor layer. A gate insulating film covering the semiconductor layer, a first conductive layer and a second conductive layer provided on the gate insulating film, a gate wiring including a gate electrode, in which a layer, an oxide semiconductor layer, and a gate electrode are stacked in this order; an insulating film covering a gate wiring including the oxide semiconductor layer; and a source wiring including a source electrode formed by laminating a third conductive layer and a fourth conductive layer in this order. The gate electrode is formed of a first conductive layer, and the gate wiring is formed of a first conductive layer and a second conductive layer. The source electrode is formed of a third conductive layer, and the source wiring is formed of the third conductive layer. The semiconductor device includes a fourth conductive layer.

[0010] Another example of the disclosed invention is a semiconductor device including an oxide semiconductor layer provided over a substrate having an insulating surface and an oxide semiconductor layer. a gate insulating film covering the nitride semiconductor layer; a first conductive layer and a second conductive layer provided on the gate insulating film; The gate wiring includes a gate electrode formed by stacking a conductive layer in this order, an oxide semiconductor layer, and a gate electrode. an insulating film covering a gate wiring including a electrode; and a gate electrode provided on the insulating film and electrically connected to the oxide semiconductor layer. a source wiring including a source electrode connected to the first conductive layer and the second conductive layer stacked in this order; The gate electrode is formed of a first conductive layer, and the gate wiring is formed of a first conductive layer. The source electrode is formed of a third conductive layer, and the source wiring is formed of a second conductive layer. The capacitor wiring is formed by the third conductive layer and the fourth conductive layer, and the capacitor wiring is formed by the fifth conductive layer and the sixth conductive layer. The semiconductor device includes a semiconductor device formed thereon.

[0011] Another example of the disclosed invention is a semiconductor device including an oxide semiconductor layer provided over a substrate having an insulating surface and an oxide semiconductor layer. a gate insulating film covering the nitride semiconductor layer; a first conductive layer and a second conductive layer provided on the gate insulating film; The gate wiring includes a gate electrode formed by stacking a conductive layer in this order, an oxide semiconductor layer, and a gate electrode. an insulating film covering a gate wiring including a electrode; and a gate electrode provided on the insulating film and electrically connected to the oxide semiconductor layer. a source wiring including a source electrode connected to the first conductive layer and the second conductive layer stacked in this order; The gate electrode is formed of a first conductive layer, and the gate electrode is formed of a second conductive layer. The line is formed of a first conductive layer and a second conductive layer, and the source electrode is formed of a third conductive layer. The source wiring is formed of the third conductive layer and the fourth conductive layer, and the capacitance wiring is formed of the fifth conductive layer and The storage capacitor is formed of the oxide semiconductor layer, the third conductive layer, the fifth conductive layer, and the sixth conductive layer. , a gate insulating film, and an insulating film.

[0012] In the above, the first conductive layer and the third conductive layer preferably have light-transmitting properties. The second conductive layer and the fourth conductive layer preferably have a light-blocking property.

[0013] In the above, the oxide semiconductor layer contains indium, gallium, or zinc. It is preferable.

[0014] An example of an oxide semiconductor that can be used in this specification is InMO3(ZnO). m (m>0), where M is gallium (Ga), iron (Fe), nickel (Ni), and One metal element selected from nickel (Ni), manganese (Mn) and cobalt (Co), or It shows multiple metal elements. For example, when Ga is selected as M, it means that only Ga is selected. Other examples include combinations of Ga and Ni, Ga and Fe, and other metal elements other than Ga. In addition to the metal element contained as M in the oxide semiconductor, Some contain Fe, Ni or other transition metal elements, or oxides of these transition metals. In this specification, among the above oxide semiconductors, those containing at least gallium as M are The material is called an In-Ga-Zn-O oxide semiconductor, and a thin film made of this material is called an In-Ga- It is sometimes called a Zn-O-based non-single crystal film.

[0015] Furthermore, by using a multi-tone mask in the above, it is possible to achieve the following with a single mask (reticle): , a light-transmitting region (a region with high light transmittance) and a light-shielding region (a region with low light transmittance) This allows the formation of a transparent region without increasing the number of masks. and a light-shielding region (a region with low light transmittance). can be formed.

[0016] In this specification, a semiconductor device is a device that can function by utilizing semiconductor characteristics. This refers to semiconductor circuits, display devices, electro-optical devices, light-emitting display devices, and electronic devices. Included in the conductor device.

[0017] In this specification, the term "display device" refers to an image display device, a light-emitting device, or a light It also refers to connectors, such as FPC (Flexible Printed Circuit) integrated circuit) or TAB (Tape Automated Bon ding) tape or TCP (Tape Carrier Package) Modules with printed wiring boards attached to the end of TAB tape or TCP or the display element is mounted on an IC (integrated circuit) by the COG (Chip On Glass) method. The display device also includes all modules in which the display device (circuit) is directly mounted. [Effects of the Invention]

[0018] In the disclosed invention, a light-transmitting transistor or a light-transmitting capacitor is formed. Therefore, even when a transistor or a capacitor is disposed in a pixel, Since light can be transmitted through the area where the transistor and the capacitor are formed, Therefore, the aperture ratio can be improved. A wiring that connects a capacitor to another capacitor, or a wiring that connects a capacitor to another capacitor The wiring can be made of materials with low resistivity and high conductivity, so the signal This reduces waveform distortion and voltage drop due to wiring resistance. [Brief explanation of the drawings]

[0019] [Figure 1] 1A and 1B are a top view and a cross-sectional view illustrating a semiconductor device. [Figure 2] 1A to 1C illustrate a method for manufacturing a semiconductor device. [Figure 3] 1A to 1C illustrate a method for manufacturing a semiconductor device. [Figure 4] 1A to 1C illustrate a method for manufacturing a semiconductor device. [Figure 5] 1A to 1C illustrate a method for manufacturing a semiconductor device. [Figure 6] 1 is a cross-sectional view illustrating a semiconductor device. [Figure 7] 1A and 1B are a top view and a cross-sectional view illustrating a semiconductor device. [Figure 8] 1A and 1B are a top view and a cross-sectional view illustrating a semiconductor device. [Figure 9] 1A and 1B are top views illustrating a semiconductor device. [Figure 10] 1A and 1B are a top view and a cross-sectional view illustrating a semiconductor device. [Figure 11] 1A and 1B are a top view and a cross-sectional view illustrating a semiconductor device. [Figure 12] 1A and 1B are top views illustrating a semiconductor device. [Figure 13] 1A and 1B are a top view and a cross-sectional view illustrating a semiconductor device. [Figure 14] 1A to 1C illustrate a method for manufacturing a semiconductor device. [Figure 15] 1A to 1C illustrate a method for manufacturing a semiconductor device. [Figure 16] 1A to 1C illustrate a method for manufacturing a semiconductor device. [Figure 17] 1A to 1C illustrate a method for manufacturing a semiconductor device. [Figure 18] 1A to 1C illustrate a method for manufacturing a semiconductor device. [Figure 19] FIG. 10 is a diagram illustrating a multi-tone mask. [Figure 20] 1A and 1B are a top view and a cross-sectional view illustrating a semiconductor device. [Figure 21] 1A to 1C illustrate a semiconductor device. [Figure 22] 1A to 1C illustrate a semiconductor device. [Figure 23] 1A and 1B are diagrams illustrating pixel equivalent circuits of a semiconductor device. [Figure 24] 1 is a cross-sectional view illustrating a semiconductor device. [Figure 25] 1A and 1B are a top view and a cross-sectional view illustrating a semiconductor device. [Figure 26] 1A and 1B are a top view and a cross-sectional view illustrating a semiconductor device. [Figure 27] 1A to 1C illustrate a semiconductor device. [Figure 28] 1A to 1C illustrate a semiconductor device. [Figure 29] 1A to 1C illustrate electronic devices. [Figure 30] 1A to 1C illustrate electronic devices. [Figure 31] 1A to 1C illustrate electronic devices. DETAILED DESCRIPTION OF THE INVENTION

[0020] The embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the description of the embodiment, and various changes in form and details are possible without departing from the spirit of the invention. It is obvious to those skilled in the art that the configurations according to the different embodiments can be combined as appropriate. In the configuration of the invention described below, the same parts Alternatively, parts having similar functions will be designated by the same reference numerals, and repeated explanations thereof will be omitted.

[0021] In this specification, the term "film" refers to a film formed over the entire surface and not patterned. And, a "layer" is something that has been patterned into a desired shape using a resist mask or the like. The distinction between "membrane" and "layer" as mentioned above is made for convenience, and the distinction between membrane and layer is not made for convenience. In addition, the terms "film" and "layer" are sometimes used without any distinction between them. They are sometimes used without distinction.

[0022] In addition, in this specification, terms with numerals such as "first," "second," or "third" refer to elements. It is given for convenience to distinguish elements, and is not limited to a specific number. The arrangement and order of steps are not limited to those shown.

[0023] (Embodiment 1) In this embodiment mode, a semiconductor device and a manufacturing process thereof will be described with reference to FIGS. do.

[0024] 1A and 1B show a semiconductor device according to this embodiment. FIG. 1A is a plan view, and FIG. 1B is a side view. 1(A) is a cross-sectional view taken along line AB in FIG.

[0025] The semiconductor device shown in FIG. 1A has a gate wiring and a capacitance wiring arranged in one direction, and a gate The source wiring is arranged in the direction 2, which intersects with the gate wiring and the capacitance wiring. It includes a pixel portion having a transistor 150a near the intersection of the wiring. In the above, the pixel portion refers to a region surrounded by a plurality of gate wirings and a plurality of source wirings. Point.

[0026] The transistor 150a shown in FIG. 1 includes an oxide semiconductor layer 150a formed on a substrate 100 having an insulating surface. 103a, a gate insulating film 104 covering the oxide semiconductor layer 103a, and the gate insulating film 104 a conductive layer 109a functioning as a gate electrode and an oxide semiconductor layer 103a provided thereover; An insulating film 112 covering the conductive layer 109a, and an oxide semiconductor layer 10 a conductive layer 117a electrically connected to the first insulating film 3a and functioning as a source electrode or a drain electrode; 117b, which is a so-called top-gate transistor.

[0027] The transistor 150a includes an oxide semiconductor layer 103a and a conductive layer serving as a gate electrode. the conductive layer 109a and the conductive layers 117a and 117b functioning as a source electrode and a drain electrode, respectively. In this way, the transistor 150a is formed of an oxide The semiconductor layer 103a, the gate electrode, the source electrode, and the drain electrode are made of a light-transmitting material. By forming the material, light can be transmitted even in the area where the transistor is formed. Therefore, the aperture ratio of the pixel can be improved.

[0028] The gate wiring electrically connected to the gate electrode of the transistor 150a is made of a light-transmitting material. A conductive layer 109a having a light-shielding property and a conductive layer 111a having a light-shielding property are laminated in this order. The source wiring electrically connected to the source electrode or the drain electrode of the transistor 150a is transparent. A conductive layer 117a having a light-shielding property and a conductive layer 119a having a light-shielding property are laminated in this order. That is, the gate electrode of the transistor 150a is a light-transmitting layer that forms a gate wiring. The source electrode or the drain electrode is formed of a part of the conductive layer 109a. The light-transmitting conductive layer 117a is formed as a part of the conductive layer 117a.

[0029] The gate wiring and the source wiring are formed by stacking a light-transmitting conductive layer and a light-shielding conductive layer in this order. By layering the gate, the wiring resistance can be reduced, and power consumption can be reduced. The wiring and source wiring are made of a conductive layer with light-shielding properties, so there is no light between the pixels. In other words, the gate wiring arranged in the row direction and the By using source wiring, the gaps between pixels can be shielded from light without using a black matrix. can be done.

[0030] In addition, the capacitance wiring is arranged in the same direction as the gate wiring. It is preferable that the light-transmitting conductive layer 109b is formed in the region overlapping with the source wiring. In the region, a light-transmitting conductive layer 109b and a light-shielding conductive layer 111b are stacked in this order. In addition, a storage capacitor 151a is formed on the capacitance wiring. 151a is connected to either the source electrode or the drain electrode of the transistor 150a. The storage capacitor 151a has the gate insulating film 104 and the insulating film 112 as dielectrics. The oxide semiconductor layer 103b, the conductive layer 109b, and the conductive layer 117b function as electrodes. It has been completed.

[0031] In this embodiment, an example is shown in which the width of the capacitance wiring and the width of the gate wiring are formed to be the same. However, the width of the capacitance wiring may be different from the width of the gate wiring. It is preferable that the width of the capacitance wiring is wider than that of the storage wiring. The area of ​​the capacitance portion 151a can be increased.

[0032] In this way, the storage capacitor 151a is connected to the oxide semiconductor layer 103b and the light-transmitting conductive layer 104b. The storage capacitor 151a is formed by the layer 109b and the conductive layer 117b. Since light can be transmitted through the thin film, the aperture ratio can be improved. In addition, by forming the storage capacitor 151a from a conductive layer having light transmission properties, the aperture ratio can be reduced. Since the storage capacitor 151a can be enlarged without causing a problem, the transistor is turned off. Even when the pixel electrode is turned on, the potential retention characteristics of the pixel electrode are improved, and the display quality is improved. The through potential can be reduced.

[0033] The transistor 150a shown in FIG. 1A can be used in a liquid crystal display device or an EL display device. The present invention can be applied to a pixel transistor provided in a pixel portion of a light-emitting display device shown in FIG. Therefore, in the illustrated example, a contact hole 126 is provided in the insulating film 120, and the insulating film A pixel electrode layer (a light-transmitting conductive layer 122b) is provided on the insulating film 120. The pixel electrode layer (the light-transmitting conductive layer 122b) is connected to the substrate 100 through the contact hole 126. ) is connected to the conductive layer 117b.

[0034] Next, an example of a manufacturing process of a semiconductor device will be described with reference to FIGS.

[0035] First, an oxide semiconductor film 101 is formed on a substrate 100 having an insulating surface (FIG. 2(A)). ), see (B)).

[0036] The substrate 100 having an insulating surface may be, for example, a visible light transparent substrate used in a liquid crystal display device or the like. The glass substrate may be a non-alkali glass substrate. The alkali-free glass substrate is preferably an aluminosilicate glass substrate. Glass materials such as aluminum borosilicate glass and barium borosilicate glass are used. Other examples of the substrate 100 having an insulating surface include a ceramic substrate, a quartz substrate, and a surface The surface of an insulating substrate made of an insulator such as a fiber substrate, or a semiconductor substrate made of a semiconductor material such as silicon The surface is covered with an insulating material, and the surface of a conductive substrate made of a conductor such as metal or stainless steel It is also possible to use one coated with an insulating material.

[0037] An insulating film serving as a base film may be provided on the substrate 100 having an insulating surface. Alkali metals (Li, Cs, Na, etc.) and alkaline earth metals (Ca, Mg, etc.) from 00 It has the function of preventing the diffusion of impurities such as other metal elements. 19 / cm 3 Less than 1 × 10 18 / cm 3 The insulating film is a silicon nitride film. , silicon oxide film, silicon nitride oxide film, silicon oxynitride film, aluminum oxide film, nitride an aluminum nitride film, an aluminum oxynitride film, an aluminum nitride oxide film, or Alternatively, it can be formed by a laminated structure of a plurality of films.

[0038] The oxide semiconductor film 101 can be formed of an In—Ga—Zn—O-based non-single-crystal film. For example, an oxide semiconductor target containing In, Ga, and Zn (In2O3:Ga2O3 The oxide semiconductor film 101 is formed by sputtering using a SiO 2 film (SiO 3 = 1:1:1). The conditions for the target are, for example, a distance between the substrate 100 and the target of 30 mm to 500 mm. , pressure 0.1Pa~2.0Pa, direct current (DC) power 0.25kW~5.0kW (diameter When using an 8-inch target, the atmosphere can be argon, oxygen, or argon. The oxide semiconductor film may be formed in a mixed atmosphere with oxygen. The oxide semiconductor film 101 may have a thickness of 5 nm to 200 nm. It should be about that level.

[0039] The sputtering method mentioned above includes RF sputtering, which uses a high frequency power supply for the sputtering power supply, and D C sputtering method, pulse DC sputtering method that applies a DC bias in a pulsed manner, etc. The RF sputtering method is mainly used to form insulating films, while the DC sputtering method is It is mainly used when forming metal films.

[0040] When an insulating film is formed, a proton is applied to the surface of the insulating film before the oxide semiconductor film 101 is formed. Plasma treatment may be performed. By performing plasma treatment, the metal particles adhering to the surface of the insulating film can be removed. This can remove any debris that may be present.

[0041] The use of a pulsed direct current (DC) power supply is preferable because it reduces dust and makes the film thickness distribution uniform. After the above-described plasma treatment, the oxide semiconductor film 101 is deoxidized without being exposed to the air. By forming the insulating film, dust and moisture are prevented from adhering to the interface between the insulating film and the oxide semiconductor film 101. This can suppress the above.

[0042] Alternatively, a multi-target sputtering device capable of installing multiple targets of different materials may be used. In sputtering equipment, different films can be stacked in the same chamber, or It is also possible to simultaneously sputter multiple types of materials to form a single film. - A method using a magnetron sputtering device equipped with a magnetic field generating mechanism inside (magnetron sputtering method) and ECR sputtering method using plasma generated by microwaves. Alternatively, a chemical reaction may be caused between the target material and the sputtering gas components during film formation. Reactive sputtering, which forms compounds from these, and vias, which apply voltage to the substrate during film formation. A sputtering method or the like may also be used.

[0043] Next, resist masks 102a and 102b are formed over the oxide semiconductor film 101. The oxide semiconductor film 101 is selectively etched using the masks 102a and 102b. Then, island-shaped oxide semiconductor layers 103a and 103b are formed (see FIGS. 2C and 2D). When using spin coating to form a resist mask, in order to improve the uniformity of the resist film, A large amount of resist material and developer is used, resulting in a large amount of wasted material. As the size of the substrate increases, the spin coating method requires a mechanism to rotate the large substrate. It is disadvantageous for mass production because it requires a large scale, and there is a large amount of loss of liquid material and waste liquid. When spin-coating a substrate of this shape, circular irregularities centered on the axis of rotation tend to occur in the coating film. Therefore, a droplet ejection method such as an inkjet method or a screen printing method is used to selectively It is preferable to form a resist material film and then expose it to light to form a resist mask. By forming a resist material film on the substrate, the amount of resist material used can be reduced. Achieve significant cost reductions with 1000mm x 1200mm, 1100mm x 1250mm It can also accommodate large area substrates such as 1150mm x 1300mm.

[0044] In this case, wet etching or dry etching may be used as the etching method. Here, wet etching using a mixture of acetic acid, nitric acid, and phosphoric acid is performed. Unnecessary portions of the oxide semiconductor film 101 are removed to form island-shaped oxide semiconductor layers 103a and 103b. After the etching, the resist masks 102a and 102b are removed. The etchant used in the wet etching is sufficient to etch the oxide semiconductor film 101. Any material that can be dry-etched is acceptable, and is not limited to the above. The gas used must be chlorine-containing or chlorine-containing gas with oxygen added. It is preferable that a gas containing chlorine and oxygen is used to form an insulating film that functions as a base film. The etching selectivity with respect to the oxide semiconductor film 101 is easily ensured, and damage to the insulating film is sufficiently prevented. This is because the

[0045] The etching equipment used for dry etching is a reactive ion etching method ( Etching equipment using the RIE method and ECR (Electron Cyclotron Resonance) and ICP (Inductively Coupled Plas) A dry etching apparatus using a high density plasma source such as SiO2 can be used. In addition, compared to ICP etching equipment, dry etching equipment allows for a uniform discharge over a wide area. The etching device is a device in which the upper electrode is grounded and the lower electrode is powered by a 13.56MHz high frequency power source. The lower electrode was connected to an ECCP (Enhanced Ceramic Plate) with a 3.2MHz low frequency power supply grounded. Etching in the (Coupled Capacitively Coupled Plasma) mode In the case of this ECCP mode etching equipment, for example, It can also accommodate substrates with a side length of more than 3m.

[0046] After that, it is advisable to carry out a heat treatment at 200 to 600°C, typically 300 to 500°C. Here, heat treatment is performed at 350°C for 1 hour in a nitrogen atmosphere. The In-Ga-Zn-O oxide semiconductor constituting the layers 103a and 103b is This heat treatment (including photo-annealing) is performed on the oxide semiconductor layers 103a and 103b. This is important in that it can release the distortion that inhibits the movement of carriers in the O3b. The heat treatment can be performed after the oxide semiconductor layers 103a and 103b are formed. Not limited to.

[0047] Next, after forming the gate insulating film 104 on the island-shaped oxide semiconductor layers 103a and 103b, A conductive film 105 is formed over the gate insulating film 104 (see FIGS. 2(E) and 2(F)).

[0048] The gate insulating film 104 may be a silicon oxide film, a silicon oxynitride film, a silicon nitride film, or a nitride oxide film. silicon oxide film, aluminum oxide film, aluminum nitride film, aluminum oxynitride film, nitride The gate electrode can be formed as a single layer or a multilayer of an aluminum oxide film or a tantalum oxide film. The gate insulating film 104 is formed to a thickness of 50 nm or more and 250 nm or less by using a sputtering method or the like. For example, the gate insulating film 104 can be formed by sputtering a silicon oxide film. Alternatively, aluminum oxide can be formed by sputtering to a thickness of 100 nm. The gate insulating film 104 can be formed to a thickness of 100 nm. It is preferable that the compound has the following structure:

[0049] By forming the gate insulating film 104 as a dense film, the oxide semiconductor layer It is possible to prevent moisture and oxygen from entering the substrates 103a and 103b. Alkali metals (Li, Cs, Na, etc.) and alkaline earth metals (Ca, Mg, etc.) contained in 00 ) or other impurities such as metal elements can be prevented from entering the oxide semiconductor layer. In addition, Na is 5 × 10 19 / cm 3 Less than 1 × 10 18 / cm 3 The following Therefore, it is possible to suppress fluctuations in the semiconductor characteristics of a semiconductor device using an oxide semiconductor. Furthermore, the reliability of the semiconductor device can be improved.

[0050] The conductive film 105 is made of indium tin oxide (ITO), Indium tin oxide with silicon oxide (ITSO), organoindium, organotin, zinc oxide (ZnO), titanium nitride, etc. can be used. Indium zinc oxide containing zinc oxide can also be used. Oxide (Indium Zinc Oxide: IZO), zinc oxide with gallium (Ga) doped with tin oxide (SnO2), indium oxide containing tungsten oxide, Indium zinc oxide with tungsten oxide, indium oxide with titanium oxide, acid Indium tin oxide containing titanium oxide may also be used. However, when a laminated structure is used, For this purpose, it is desirable that the light transmittance of all of the multiple films is sufficiently high.

[0051] Next, resist masks 107a and 107b are formed over the conductive film 105. The conductive film 105 is selectively etched using the etching masks 107a and 107b to form the conductive layer 109a. After the etching, a resist pattern 109b is formed (see FIGS. 2(G) and 2(H)). The masks 107a and 107b are removed. At this time, the masks 107a and 107b are removed to prevent the insulating film 112 from being covered. To improve the performance and prevent breakage, the edge of the gate electrode is tapered. It is preferable to form the gate electrode using the conductive film described above, such as a gate wiring. This includes electrodes and wiring.

[0052] Next, a conductive film 106 is formed on the gate insulating film 104 and the conductive layers 109a and 109b (FIG. (See 3(A) and (B)).

[0053] The conductive film 106 is made of aluminum (Al), tungsten (W), titanium (Ti), tantalum (Ta), or the like. Ta (Ta), Molybdenum (Mo), Nickel (Ni), Platinum (Pt), Copper (Cu), Gold ( Metallic materials such as Au, silver (Ag), manganese (Mn), neodymium (Nd), or The alloy material mainly composed of these metal materials or the nitrides composed of these metal materials are used. It can be formed as a single layer or a multilayer. It is made of a low-resistance conductive material such as aluminum. It is desirable to achieve this.

[0054] When the conductive film 106 is formed on the conductive film 105 (or the conductive layers 109a and 109b), For example, if ITO is used for the conductive film 105, If aluminum is used for the film 106, a chemical reaction may occur. In order to prevent a chemical reaction from occurring, a high melting point For example, examples of high melting point materials include molybdenum, titanium, Examples include tungsten, tantalum, and chromium. In particular, it is preferable to use a material with high conductivity to form the conductive film 106 as a multi-layer film. Examples of materials with high conductivity include aluminum, copper, and silver. When forming a laminated structure, the first layer is molybdenum, the second layer is aluminum, and the third layer is Layers of molybdenum, or aluminum with a molybdenum first layer and a trace of neodymium in the second layer. The first layer can be made of aluminum, and the third layer can be made of molybdenum.

[0055] Next, a resist mask 110 is formed over the conductive film 106. The conductive film 106 is etched using the etching method (see FIGS. 3(C) and 3(D)). As a result, the conductive film 106 is left unremoved by the resist mask 110. The conductive layer 109a is exposed by removing the conductive layer 109a except for the portion where the conductive layer 109a is formed. The surface area of ​​the conductive layer 111a is different from that of the conductive layer 109a. The surface area of ​​the conductive layer 111a is larger than the surface area of ​​the conductive layer 111a. The conductive layer 111a and the conductive layer 109a are overlapped with each other in the region where the conductive layer 111a and the conductive layer 109a overlap. and a region where the conductive layer 111a and the conductive layer 109a do not overlap.

[0056] At least in the region where the conductive layer 111a having the light-shielding property is present, it functions as a gate wiring and is transparent. The region where the conductive layer 109a having optical properties is present functions as a gate electrode. The conductive layer 109a, which functions as a gate electrode, is formed of a light-transmitting material. Since light can be transmitted through the areas where the In addition, the conductive layer 111a functioning as the gate wiring can be formed by a conductive layer having a light-shielding property. By forming the wiring layer from an insulating layer, it is possible to reduce wiring resistance and power consumption. The gate wiring is made of a conductive layer having a light-shielding property, and therefore, light is shielded between pixels. In addition, the contrast can be improved.

[0057] After the conductive layers 109a and 109b are formed, the conductive layer 111a having a light-shielding property is formed. However, the order of forming the gate wiring may be reversed. After forming the conductive layer 111a having a light-shielding property that functions as a gate electrode, It is also possible to form conductive layers 109a and 109b having a high conductivity (see FIGS. 8(A) and 8(C)). ).

[0058] In addition, as shown in Figures 3(C) and (D), the capacitance wiring is arranged in the same direction as the gate wiring. In the pixel region, the capacitor wiring is preferably formed using the light-transmitting conductive layer 109b. However, in the region overlapping with the source wiring to be formed later, the conductive layer 109b having light transmitting properties is formed. The conductive layer 111b having a light-blocking property may be stacked in this order (see FIG. 1A). With such a configuration, the resistance can be reduced.

[0059] In this embodiment, an example is shown in which the width of the capacitance wiring and the width of the gate wiring are formed to be the same. However, the width of the capacitance wiring may be different from the width of the gate wiring. It is preferable to make the surface area of ​​the storage capacitor 151a larger than the width of the port wiring. It is possible.

[0060] After the oxide semiconductor layers 103a and 103b are formed, the gate insulating film 104 is formed. After the formation of the electrode, a part of the oxide semiconductor layers 103a and 103b or Alternatively, a process for increasing the conductivity of the entire region may be performed. For example, the process for increasing the conductivity may be The silicon nitride containing hydrogen is formed on the upper surface of the oxide semiconductor layer 103b. The oxide semiconductor layer can be subjected to hydrogenation treatment by being placed in a heated state and heated. Alternatively, hydrogenation can be achieved by applying heat in a hydrogen atmosphere. As shown in FIG. 1, a channel protection layer is formed in a region overlapping with a channel formation region of the oxide semiconductor layer 103a. By forming the protective layer 127, the conductivity of the oxide semiconductor layer 103a is selectively increased. A recessed area can be formed.

[0061] The channel protection layer 127 is preferably made of silicon oxide. This can reduce the amount of hydrogen entering the channel portion of the conductor layer 103a. The channel protection layer 127 may be removed after a treatment to increase the conductivity. The protective layer 127 can also be formed of a resist. In that case, after the hydrogenation treatment, It is preferable to remove the resist. On the other hand, by performing a process to increase conductivity, it becomes easier for the transistor current to flow and the capacitance The resistance of the electrodes of the element can be reduced.

[0062] In FIG. 6, the channel protection layer 127 is provided in contact with the oxide semiconductor layer 103a. However, it may be provided on the gate insulating film 104. The shape of the conductive layer 109a functioning as an electrode is adjusted to make the channel protection layer 109b thicker than the conductive layer 109a. Layer 127 can be made larger to form an offset region.

[0063] Next, a film is formed on the conductive layers 109a and 109b and the gate insulating film 104 to serve as an interlayer insulating film. After forming the insulating film 112, a contact hole is formed in the insulating film 112 so as to reach the oxide semiconductor layer. A hole is formed on the oxide semiconductor layer to expose a part of the surface of the oxide semiconductor layer (see FIGS. 3E and 3F).

[0064] The insulating film 112 is formed of a material containing oxygen or nitrogen, such as silicon oxide, silicon nitride, silicon oxynitride, or silicon nitride oxide. insulating films, carbon-containing films such as DLC (diamond-like carbon), epoxy, Polyimide, polyamide, polyvinylphenol, benzocyclobutene, acrylic, etc. A film made of a siloxane material such as a polymeric material or a siloxane resin is provided in a single layer or laminate structure. Note that the insulating film 112 preferably has a light-transmitting property.

[0065] Next, a conductive film 113 is formed over the insulating film 112 (see FIGS. 3G and 3H).

[0066] The conductive film 113 is preferably formed of substantially the same material as the conductive film 105. "Almost the same material" means that the main element is the same, and there is no difference in the impurity level. In this way, the types and concentrations of elements used may differ. By this, when the conductive film 113 is formed by sputtering or vapor deposition, the conductive film 105 and the material The advantage of being able to share materials is that the same manufacturing equipment can be used. This allows the manufacturing process to run smoothly and improves throughput. This makes it possible to reduce costs.

[0067] Next, resist masks 115a and 115b are formed over the conductive film 113. The conductive film 113 is selectively etched using the etching masks 115a and 115b to form a conductive layer 117a. and a conductive layer 117b are formed (see FIGS. 4A and 4B). The resist masks 115a and 115b are subsequently removed.

[0068] Next, a conductive film 114 is formed on the conductive layers 117a and 117b and the insulating film 112 (FIG. 4(C) ), see (D)).

[0069] The conductive film 114 is made of aluminum (Al), tungsten (W), titanium (Ti), tantalum (Ta), or the like. Ta (Ta), Molybdenum (Mo), Nickel (Ni), Platinum (Pt), Copper (Cu), Gold ( Metallic materials such as Au, silver (Ag), manganese (Mn), neodymium (Nd), or The alloy material mainly composed of these metal materials or the nitrides composed of these metal materials are used. It can be formed as a single layer or a multilayer. It is made of a low-resistance conductive material such as aluminum. It is desirable to achieve this.

[0070] The conductive film 114 may be formed of a material different from that of the conductive film 106. Alternatively, the conductive film 114 may be formed to have a different layer structure from that of the conductive film 106. This is because the temperature applied in the manufacturing process of the semiconductor device is This is because the conductive film 106 is often different from the conductive film 106. Therefore, the conductive film 106 is preferably made of a material having a higher melting point or a laminated structure. Alternatively, the conductive film 106 may be made of a material that is less likely to cause hillocks. Alternatively, the conductive film 114 may be a signal layer to which a video signal is supplied. Since the conductive film 106 may be formed as a wiring, a material or a laminated structure having a lower wiring resistance than the conductive film 106 is used. It is preferable to use

[0071] The same as when the conductive film 106 is formed on the conductive film 105 (or the conductive layers 109a and 109b). Similarly, the conductive film 114 was formed on the conductive film 113 (or the conductive layers 117a and 117b). In this case, the two films may react with each other. When forming the conductive film 114, a high melting point material is also formed between the conductive film 113 and the conductive film 114. For example, examples of high melting point materials include molybdenum, titanium, and titanium. Examples of high melting point materials include tantalum, chromium, etc. Then, on top of the film made of high melting point material, It is preferable to form the conductive film 114 as a multilayer film using a material with high conductivity. High-yield materials include aluminum, copper, and silver.

[0072] Next, a resist mask 118 is formed over the conductive film 114. The conductive film 114 is etched using the etching method (see FIGS. 4(E) and 4(F)). As a result, the conductive film 114 is left unremoved by the resist mask 118. The conductive layer 117a is exposed by removing the conductive layer 117a except for the portion where the conductive layer 117a is formed. The surface area of ​​the conductive layer 119a is different from that of the conductive layer 117a. The surface area of ​​the conductive layer 117a is larger than the surface area of ​​the conductive layer 119a. The conductive layers 119a and 117a are formed in an area where the conductive layers 119a and 117a overlap each other and in an area where the conductive layers 119a and 117a overlap each other. The conductive layer 119a and the conductive layer 117a do not overlap each other.

[0073] At least in the region where the conductive layer 119a having the light-shielding property is present, it functions as a source wiring and is transparent. The region where the conductive layer 117a having optical properties is provided functions as a source electrode or a drain electrode. The conductive layers 117a and 117b serving as source and drain electrodes are formed by a light-transmitting By forming the conductive layer having the above structure, the conductive layer can be formed in the portion where the source electrode or the drain electrode is formed. Since light can be transmitted even when the film is thin, the aperture ratio of the pixel can be improved. The conductive layer 119a functioning as a source wiring is formed of a conductive layer having a light-shielding property. This reduces the wiring resistance and power consumption. Since the conductive layer 119a has a high conductivity, light can be shielded between the pixels. That is, the gate wiring arranged in the row direction and the source wiring arranged in the column direction Therefore, the gaps between pixels can be shielded from light without using a black matrix.

[0074] After the conductive layers 117a and 117b are formed, the conductive layer 119a having a light-shielding property is formed. However, the order of forming the source wiring may be reversed. After forming the conductive layer 119a having a light-shielding property, a source electrode or a drain electrode is formed. It is also possible to form conductive layers 109a and 109b having light-transmitting properties that function as a conductive layer (FIG. 8( (See A), (B)).

[0075] In addition, in FIGS. 4(E) and 4(F), the conductive layer 117b serves as an electrode of the storage capacitor 151a. The capacitance wiring has a storage capacitance portion 151a formed between the gate insulating film 104 and the insulating film 11. 2 is used as a dielectric, and the oxide semiconductor layer 103b, which functions as an electrode, and the conductive layer 109b and the conductive This structure allows the resistance to be reduced. do.

[0076] In this way, by forming the storage capacitor 151a with a light-transmitting conductive layer, Since light can be transmitted through the portion where the storage capacitor 151a is formed, the opening In addition, the storage capacitor 151a is made of a light-transmitting material. By doing so, the storage capacitor 151a can be made larger, so that the transistor Even when the pixel electrode is turned off, the potential retention characteristics of the pixel electrode are improved, improving the display quality. The feed-through potential can be reduced.

[0077] Through the above steps, the transistor 150a and the storage capacitor portion 151a can be manufactured. The transistor 150a and the storage capacitor 151a can be light-transmitting elements. The oxide semiconductor layer 103b is used as a storage capacitor, and the gate insulating film 104 is used as a dielectric. When forming a capacitor, the potential of the capacitor wiring formed by the conductive layer 109b is set to the potential of the counter electrode. The potential of the oxide semiconductor layer 103b can be set higher than the potential of the common line. Charge can be induced, and the oxide semiconductor layer 103b functions as an electrode of a storage capacitor. On the other hand, when a storage capacitor portion is formed without using the oxide semiconductor layer 103b, or the oxide semiconductor layer 103b is subjected to treatment for increasing the conductivity by hydrogenation or the like. If the wiring is connected to the opposite electrode (common electrode), the potential may be the same as that of the opposing electrode (common electrode). The number can be reduced.

[0078] Next, after forming the insulating film 120, a resist mask (not shown) is formed on the insulating film 120. Then, the insulating film 120 is etched using the resist mask, and a contact is formed on the insulating film 120. The insulating film 120 is formed in the transistor 150. a, which functions as an insulating film for flattening the surface on which the storage capacitor 151a or wiring is formed The transistor 150a and the storage capacitor 151a can be formed using a light-transmitting Since they can be formed as elements, the area where they are arranged can also be used as an opening area. Therefore, the transistor 150a, the storage capacitor 151a, or the It is beneficial to smooth out the unevenness caused by lines and make the top surface on which these elements are formed flat. be.

[0079] The insulating film 120 also functions as an insulating film to protect the transistor 150a from impurities and the like. The insulating film 120 can be formed of, for example, a film containing silicon nitride. A film containing silicon nitride is suitable because it has a high effect of blocking impurities. Alternatively, the insulating film 120 can be formed of a film containing an organic material. Examples of organic materials include: Acrylic, polyimide, polyamide, etc. are suitable as the organic material. Therefore, the insulating film 120 is preferably made of a material containing silicon nitride. When a laminated structure is formed by a film containing silicon nitride and a film containing an organic material, the film containing silicon nitride on the lower side It is preferable to place an insulating film 120 on the insulating film 120 and place a film containing an organic material on the insulating film 120. When forming the light-transmitting layer in a laminated structure, it is desirable that each film has a sufficiently high light transmittance. In this case, the insulating film 120 is etched. Therefore, no contact holes are formed.

[0080] The insulating film 120 can also function as a color filter. By providing a color filter on the 00 side, it is not necessary to provide a color filter on the opposing substrate side. This eliminates the need for margins to adjust the positions of the two boards, allowing for a The insulating film 120 may not be formed. Alternatively, the pixel electrode may be located on the same layer as the source wiring.

[0081] Next, a conductive film 121 is formed on the insulating film 120 and the contact holes (FIG. 5(C), ( The conductive film 121 is made of substantially the same material as the conductive films 105 and 113. In this way, by using roughly the same material, When the conductive film 121 is formed by sputtering or vapor deposition, the conductive film 105 and the conductive film 113 are formed of the same material. The advantage of being able to share materials is that the same manufacturing equipment can be used. This allows the manufacturing process to run smoothly and improves throughput. This makes it possible to reduce costs.

[0082] Next, a resist mask (not shown) is formed over the conductive film 121. The conductive film 121 is selectively etched to form conductive layers 122a and 122b (FIG. 5). (See (E) and (F)). After the etching, the resist mask is removed.

[0083] The conductive layers 122a and 122b can function as pixel electrodes. 22a and 122b are connected to the source wiring, the source electrode, and the gate wiring through contact holes. The gate electrode, pixel electrode, capacitance wiring, electrodes of the storage capacitance section, etc. can be connected to each other. Therefore, the conductive layers 122a and 122b can be used as wiring for connecting conductors. It can be made to function as such.

[0084] In this manner, a semiconductor device can be manufactured. A light-transmitting transistor 150a and a light-transmitting storage capacitor 151a are formed. Therefore, even when a transistor or a storage capacitor is disposed in a pixel, Light can be transmitted through the area where the transistor and storage capacitor are formed. Therefore, the aperture ratio can be improved. The wiring connecting the transistors should be made of a material with low resistivity and high conductivity. This reduces distortion of the signal waveform and voltage drop due to wiring resistance. Cut.

[0085] Next, another example of the semiconductor device will be described with reference to FIG. 7. The semiconductor device shown in FIG. The device has many parts in common with that of Figure 1. Therefore, in the following, the overlapping parts will be 7(A) is a plan view, and FIG. 7(B) is a perspective view. is a cross-sectional view taken along line AB in FIG. 7(A), and FIG. 7(C) is a cross-sectional view taken along line C in FIG. 7(A). -D is a cross-sectional view.

[0086] In FIG. 1, the gate wiring and the source wiring are formed by forming a light-shielding conductive layer on a light-transmitting conductive layer. However, the order of the light-shielding conductive layer and the light-transmitting conductive layer may be omitted. A light-transmitting conductive layer that functions as a gate electrode can also be formed (see FIG. 7). 109a is connected to a conductive layer 111a having a light-shielding property and functioning as a gate wiring. Similarly to the gate wiring, a light-transmitting material that functions as a source electrode or a drain electrode may be used. The conductive layer 117a is connected to a conductive layer 119a having a light-shielding property and functioning as a source wiring. It is fine as long as it is.

[0087] Next, another example of the semiconductor device will be described with reference to FIG. 8. The semiconductor device shown in FIG. The device has many parts in common with that of Figure 1. Therefore, in the following, the overlapping parts will be 8A is a plan view, and FIG. 8B is a perspective view. is a cross-sectional view taken along line AB in FIG. 8(A), and FIG. 8(C) is a cross-sectional view taken along line C in FIG. 8(A). -D is a cross-sectional view.

[0088] In FIG. 1, the gate wiring and the source wiring are formed by a light-transmitting conductive layer and a light-shielding conductive layer. However, the gate wiring and the source wiring are made of a conductive layer having a light-shielding property. A light-transmitting conductive layer 1 that functions as a gate electrode can also be formed (see FIG. 8). The conductive layer 111a having a light-shielding property and functioning as a gate wiring is connected to the conductive layer 111a. Similarly to the gate wiring, a light-transmitting material that functions as a source electrode or a drain electrode may be used. The conductive layer 117a is connected to the conductive layer 119a having a light-shielding property and functions as a source wiring. It would be good if it was done.

[0089] In addition, when a transistor is fabricated on a gate wiring, the size of the transistor is determined by the Although it depends on the gate wiring width of the transistor, in this embodiment, a transistor is formed in the pixel. For example, as shown in Figure 9, As shown in the figure, the transistor channel width W is longer than the gate wiring width, or the channel length L is By making the transistor larger, Its current capacity can be increased sufficiently, and the time it takes to write signals to pixels can be shortened. Alternatively, the off-state current can be reduced, and flickering and the like can be reduced. This makes it possible to provide a high-definition display device.

[0090] The pixel configuration is not limited to that shown in FIG. 1. For example, as shown in FIG. First, the pixel electrodes are overlapped with the gate wiring and insulating film of the adjacent pixels via the gate insulating film. A quantity can be set.

[0091] Next, another example of the semiconductor device will be described with reference to FIG. 11. The conductor arrangement is largely the same as that of FIG. 1. Therefore, in the following, the overlapping 11A is a plan view, and the same parts as those in FIG. 1 are omitted. 1(B) is a cross-sectional view taken along line AB in FIG. 11(A).

[0092] The difference between FIG. 11 and FIG. 1 is that an oxide semiconductor layer is not used as an electrode of the storage capacitor 151c. a light-transmitting conductive layer 109c which forms a capacitor wiring, and a source electrode or a drain electrode Therefore, the capacitance wiring is formed by using the conductive layer 117c which functions as a counter electrode. In addition, the storage capacitor 151c can be formed using an oxide semiconductor layer. Since the conductive layer 109c and the conductive layer 109d shown in FIG. The surface area of ​​the conductive layer 117c can be made larger than that of the conductive layer 109b and the conductive layer 117b shown in FIG. It is preferable that the size of the storage capacitor 151c is 70% or more, or 80% or more of the pixel pitch. It is also preferable that the contact of the pixel electrode is formed on the conductive layer 119b on the conductive layer 117c. Since the configuration is the same as that shown in FIG. 1, detailed explanation will be omitted below. .

[0093] By adopting such a configuration, the storage capacitor 151c having high light transmittance is formed large. By increasing the capacitance of the storage capacitor 151c, the transistor can be turned off. Even when the pixel electrode is turned on, the potential retention characteristics of the pixel electrode are improved, and the display quality is improved. The through potential can be reduced. Even if the storage capacitor 151c is formed, light can be transmitted through the portion where the storage capacitor 151c is formed. Therefore, the aperture ratio can be increased and power consumption can be reduced. Even if the liquid crystal alignment is disturbed by the unevenness caused by the contact holes, the light-shielding conductive film The conductive layer 119b can prevent light leakage.

[0094] Next, another example of the semiconductor device will be described with reference to FIG. 12. The conductor arrangement is largely the same as that of FIG. 1. Therefore, in the following, the overlapping The parts are omitted and only the differences are explained. Also, Fig. 12 is a plan view.

[0095] FIG. 12 shows an example of an EL display device as an example of a pixel configuration. The gate wiring is formed by stacking the layer 109a and the conductive layer 111a in this order, and the conductive layers 117a and 119a The source wiring, the switching transistor 150a, and the driving transistor 150b are stacked in this order. The capacitor 150c, the storage capacitor 151d, the conductive layer 117e and the conductive layer 119c are stacked in this order. It has a power line that is connected to the power supply.

[0096] The transistor 150a shown in FIG. 12 is similar to the transistor 150a shown in FIG. an oxide semiconductor layer 103a and an oxide semiconductor layer 103b over a substrate having an insulating surface; a gate insulating film covering the gate electrode; and a conductive layer 1 functioning as a gate electrode provided on the gate insulating film. an insulating film covering the oxide semiconductor layer 103a and the conductive layer 109a; The oxide semiconductor layer 103a is electrically connected to the oxide semiconductor layer 103b and functions as a source electrode or a drain electrode. The driving transistor 15 is made up of conductive layers 117a and 117b. 0c is a substrate having an insulating surface, an oxide semiconductor layer 103c, and an oxide semiconductor layer 103c. a gate insulating film covering the gate electrode and a conductive layer 10 functioning as a gate electrode provided on the gate insulating film. 9d, an insulating film 112 covering the oxide semiconductor layer 103c and the conductive layer 109d, and the insulating film 112 and a source electrode or a drain electrode. The storage capacitor 151d has conductive layers 117e and 117f that function as electrodes. The insulating film and the insulating film are used as a dielectric to form the oxide semiconductor layer 103d, which functions as an electrode, and the conductive film It is composed of layer 109d and conductive layer 117e.

[0097] The semiconductor device shown in FIG. 12 includes a switching transistor 150a, a driving transistor 150b, and a Although the case where a pixel has two transistors, i.e., 150c, has been described, it is also possible to use three transistors in one pixel. The above transistors may also be provided.

[0098] In this way, even when two or more transistors are provided in one pixel, the transistor Since light can be transmitted through the area where the capacitor is formed, the aperture ratio can be increased. Cut.

[0099] In addition, in the peripheral driving circuits such as the protection circuit, gate driver, and source driver, Therefore, the pixel area does not need to have a transparent transistor or capacitor. The transistors in the peripheral driver circuit are made of a material with light blocking properties. It may also be formed by

[0100] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0101] (Embodiment 2) In this embodiment mode, an example of a manufacturing process of a semiconductor device will be described with reference to FIGS. Note that the semiconductor device and the manufacturing process thereof in this embodiment mode are mostly the same as those of the conventional semiconductor device. This is common to Form 1. Therefore, in the following, we will omit the overlapping parts and focus on the differences. will be explained in detail.

[0102] 13A and 13B show a semiconductor device according to this embodiment. FIG. 13A is a plan view, and FIG. 13B is a plan view. 13B) is a cross-sectional view taken along line AB in FIG. 13A.

[0103] 13 is different from FIG. 1 in that the oxide semiconductor layer for the transistor 150a is 103a for the storage capacitor portion 151a and an oxide semiconductor layer 103b for the storage capacitor portion 151a are formed. In the example shown in FIG. 13, the oxide semiconductor layer of the transistor 250 and the oxide semiconductor layer of the storage capacitor 251 are The point is that it is an island.

[0104] With such a structure, the layout for forming the oxide semiconductor layer can be easily In addition, the number of contact holes can be reduced, which reduces the contact resistance. Furthermore, contact failures can be reduced.

[0105] Next, an example of a manufacturing process of a semiconductor device will be described with reference to FIGS. In this embodiment mode, a case where a semiconductor device is manufactured using a multi-tone mask will be described. .

[0106] First, oxide semiconductor layers 203a and 203b are formed on a substrate 200 having an insulating surface. (See Figures 14(A) and (B)).

[0107] The material of the substrate 200 and the materials and manufacturing methods of the oxide semiconductor layers 203a and 203b are described in detail in the following. The substrate 100 and the oxide semiconductor layers 103a and 103b shown in the first embodiment can be referred to. In addition, an insulating film that functions as a base film may be provided over the substrate 200 having an insulating surface. .

[0108] Next, a gate insulating film 204, a conductive film 205, and a conductive film 206 are formed on the oxide semiconductor layers 203a and 203b. A film 206 is formed (see FIGS. 14(C) and (D)).

[0109] The materials and manufacturing methods of the gate insulating film 204, the conductive film 205, and the conductive film 206 are as follows: The gate insulating film 104, the conductive film 105, and the conductive film 106 shown in Embodiment 1 can be referred to. do.

[0110] Next, resist masks 207a and 207b are formed over the conductive film 206. 207a and 207b are patterns having regions of different thicknesses by using a multi-tone mask. By using a multi-tone mask, it is possible to form a resist mask. This is preferable because the number of sheets of the conductive film is reduced and the manufacturing process is also reduced. A process of forming patterns of the films 205 and 206 and a process of forming patterns of the conductive films 213 and 214 In this step, a multi-tone mask can be used.

[0111] A multi-tone mask is a mask that can perform exposure with multiple levels of light intensity. Representative examples include: Exposure is performed at three levels of light intensity: exposed area, semi-exposed area, and unexposed area. By doing so, a single exposure and development process can be performed to produce a film having multiple (typically two) thicknesses. A resist mask can be formed. Therefore, by using a multi-tone mask, This allows reducing the number of masks required.

[0112] 19(A-1) and 19(B-1) show cross sections of a typical multi-tone mask. (A-1) shows a gray-tone mask 403, and (B-1) shows a half-tone mask. The mask 414 is shown.

[0113] The gray-tone mask 403 shown in FIG. 19(A-1) is a light-shielding mask on a light-transmitting substrate 400. The light-shielding portion 401 is formed by a light-shielding layer, and the diffraction grating portion 4 is formed by a pattern of the light-shielding layer. It consists of 02.

[0114] The diffraction grating section 402 is made up of slits and dots spaced at intervals equal to or less than the resolution limit of the light used for exposure. The diffraction grating portion 402 has a groove or a mesh, and thereby the transmittance of light is controlled. The slits, dots or meshes provided may be periodic or non-periodic. It may also be something.

[0115] The light-transmitting substrate 400 may be made of quartz or the like. The light-shielding layer constituting the grating portion 402 may be formed using a metal film, preferably chromium. Alternatively, it may be made of chromium oxide or the like.

[0116] When the gray-tone mask 403 is irradiated with light for exposure, the pattern shown in FIG. 19(A-2) is formed. In this way, the light transmittance in the area overlapping the light-shielding portion 401 is 0%, and the light transmittance in the area overlapping the light-shielding portion 401 or the The light transmittance in the area where the diffraction grating portion 402 is not provided is 100%. The transmittance of the sub-portion 402 is generally in the range of 10% to 70%, and the slits of the diffraction grating, This can be adjusted by adjusting the spacing of the dots or meshes.

[0117] The halftone mask 414 shown in FIG. 19(B-1) is a semi-transparent mask formed on a light-transmitting substrate 411. It is composed of a semi-transparent portion 412 formed by a transparent layer and a light-shielding portion 413 formed by a light-shielding layer. It has been done.

[0118] The semi-transparent portion 412 is a layer of MoSiN, MoSi, MoSiO, MoSiON, CrSi, etc. The light-shielding portion 413 can be formed using the same material as the light-shielding layer of the gray-tone mask. It may be formed using a metal film, preferably chromium or chromium oxide.

[0119] When the halftone mask 414 is irradiated with light for exposure, the pattern shown in FIG. 19(B-2) is formed. In this way, the light transmittance in the area overlapping the light-shielding portion 413 is 0%, and the light transmittance in the area overlapping the light-shielding portion 413 or the semi-transparent portion is 0%. The light transmittance in the area where the light transmitting portion 412 is not provided is 100%. The light transmittance of 412 is generally in the range of 10% to 70%, and the type or shape of the forming material It can be adjusted by the thickness of the film formed.

[0120] By using a multi-tone mask, three exposure areas, exposed area, intermediate exposed area, and unexposed area, can be obtained. A light level mask can be formed, and multiple (typically It is possible to form a resist mask having regions of different thicknesses (two types in total). By using a multi-tone mask, the number of photomasks can be reduced.

[0121] The halftone masks shown in FIGS. 14(E) and 14(F) are formed by depositing a semi-transparent layer on a light-transmitting substrate 300. The conductive film 206 is composed of layers 301a and 301b and a light-shielding layer 301c. On the top, a resist mask 2 is applied to the portions that will later become the electrodes and gate electrodes of the storage capacitor 251. A resist mask 207 is formed on the area that will later become the gate wiring. a is formed thickly (see 14(E) and (F)).

[0122] Using resist masks 207a and 207b, unnecessary portions of the conductive films 205 and 206 are selected. The conductive layers 208a, 209a and the conductive layers 208b, 209b are formed by selectively etching and removing the conductive layers. (See Figures 15(A) and (B)).

[0123] Next, the resist masks 207a and 207b are ashed with oxygen plasma. The resist masks 207a and 207b are ashed with oxygen plasma. As a result, the resist mask 207b is removed and the conductive layer 208b is exposed. The resist mask 207a shrinks and remains as a resist mask 210 (FIG. 15(C), ( D). In this way, by using a resist mask formed with a multi-tone mask, Since an additional resist mask is not required, the process can be simplified.

[0124] Next, the conductive layers 208a and 208b are etched using the resist mask 210. (See FIGS. 16(A) and 16(B)). After the etching, the resist mask 210 is removed. do. As a result, the conductive layer 208b is removed, and the conductive layer 209b is exposed. a is removed except for the portion where the resist mask 210 is formed, and the conductive layer 209a is As a result, the conductive layers 208a and 209a are exposed to the outside. That is, the surface area of ​​the conductive layer 209a is much larger than that of the conductive layer 208a. Alternatively, the conductive layer 208a and the conductive layer 209a may have a surface area larger than that of the conductive layer 208a. and the conductive layer 209a overlap, and the conductive layer 208a and the conductive layer 209a overlap. It has areas where there is no

[0125] At least in the region where the conductive layer 211a having the light-shielding property is present, it functions as a gate wiring and is transparent. The region where the conductive layer 209a having optical properties is present functions as a gate electrode. The conductive layer 209a, which functions as a light-transmitting layer, is formed of a light-transmitting material. In addition, the conductive layer 209a and the conductive layer 209b functioning as gate wirings can be formed. 211a, a light-transmitting conductive layer and a light-shielding conductive layer are laminated in this order. This reduces wiring resistance and power consumption. Since the conductive layer is configured using the conductive layer having the above structure, light can be shielded between pixels.

[0126] In addition, capacitance wiring is arranged in the same direction as the gate wiring. It is preferable to form the conductive layer 209b having light-transmitting properties. In the overlapping region, the light-transmitting conductive layer 209b and the light-blocking conductive layer 211b They may be laminated in this order.

[0127] In this way, by using a multi-tone mask, it is possible to obtain a transparent region ( By forming a light-shielding area (area with high light transmittance) and a light-shielding area (area with low light transmittance), This allows the area having light transmittance (light transmittance) to be increased without increasing the mask. It is possible to form a light-shielding region (a region with high light transmittance) and a light-shielding region (a region with low light transmittance). .

[0128] Next, a film is formed on the conductive layers 209a, 209b and the gate insulating film 204 to serve as an interlayer insulating film. After forming the insulating film 212, a contact hole is formed in the insulating film 212 so as to reach the oxide semiconductor layer. A hole is formed on the insulating film 212 to expose part of the surface of the oxide semiconductor layer. For a method thereof, the description of the insulating film 112 in Embodiment 1 can be referred to.

[0129] Next, a conductive film 213 and a conductive film 214 are formed on the insulating film 212 (FIGS. 16(C) and 16(D)). )). Materials and manufacturing methods of the conductive films 213 and 214 are the same as those in Embodiment 1. 1 and 2. The conductive films 113 and 114 shown in FIG.

[0130] Next, resist masks 215a and 215b are formed on the conductive film 214 using a half-tone mask. b is formed (see Figures 17(A) and (B)). The half-tone mask is a light-transmitting substrate. The conductive film 302 is composed of a semi-transparent layer 303b and a light-shielding layer 303a. On the portion 214 that will later become a source electrode or a drain electrode, a thin resist mask 21 is formed. 5b, a thick resist mask 215a is formed on the portion that will later become the source wiring.

[0131] Using resist masks 215a and 215b, unnecessary portions of the conductive films 213 and 214 are selected. The conductive layers 216a, 217a and the conductive layers 216b, 217b are selectively etched away. (See Figures 17(C) and (D)).

[0132] Next, the resist masks 215a and 215b are ashed with oxygen plasma. The resist masks 215a and 215b are ashed with oxygen plasma. As a result, the resist mask 215b is removed and the conductive layer 217b is exposed. The resist mask 215a is shrunk and remains as a resist mask 218. By using a resist mask formed by a masking mask, an additional resist mask can be used. This eliminates the need for a separate process, thereby simplifying the process.

[0133] Next, the conductive layers 216a and 216b are etched using the resist mask 218. As a result, the conductive layer 216b is removed, and the conductive layer 217 is b is exposed. In addition, the conductive layer 216a is exposed in the area where the resist mask 218 is formed. The conductive layer 219a is then removed, leaving only the conductive layer 219a. The surface area of ​​each layer is significantly different from that of the conductive layer 217a. The surface area of ​​the conductive layer 219a is larger than the surface area of ​​the conductive layer 219a. The conductive layer 217a is a region where the conductive layer 219a and the conductive layer 217a overlap, and a region where the conductive layer 219a and the conductive layer 217a overlap. 9a and the conductive layer 217a do not overlap. Then, the resist mask 218 is removed.

[0134] At least in the region where the conductive layer 219a having the light-shielding property is present, it functions as a source wiring and is transparent. The region where the conductive layer 217a having optical properties is present functions as a source electrode or a drain electrode. The conductive layers 217a and 217b serving as source and drain electrodes are formed by a light-transmitting By forming the conductive layer having the above structure, the aperture ratio of the pixel can be improved. The conductive layers 217a and 219a functioning as source wirings are formed by a light-transmitting conductive layer. By laminating a conductive layer having a light-shielding property in this order, the wiring resistance is reduced, and power consumption is reduced. In addition, the source wiring is formed using a conductive layer 219a having a light-shielding property. In other words, the gate arrays arranged in the row direction The line and the source wiring arranged in the column direction allow for the The gaps between pixels can be shielded from light.

[0135] The conductive layer 217a also functions as an electrode of the storage capacitor 251. The capacitance portion 251 functions as an electrode with the gate insulating film 204 and the insulating film 212 as dielectrics. The insulating film 201 includes an oxide semiconductor layer 203a, a conductive layer 209b, and a conductive layer 217b.

[0136] In this way, by forming the storage capacitor 251 with a light-transmitting conductive layer, Since light can be transmitted through the portion where the storage capacitor 251 is formed, the aperture ratio can be increased. Furthermore, by forming the storage capacitor 251 from a light-transmitting material, This allows the storage capacitor 251 to be increased, so that the transistor is turned off. Even when the voltage is high, the potential retention characteristics of the pixel electrode are improved, improving the display quality. The loop potential can be reduced.

[0137] In this manner, the transistor 250 and the storage capacitor portion 251 can be manufactured. The transistor 250 and the storage capacitor 251 can be light-transmitting elements.

[0138] Next, after forming the insulating film 220, a resist mask (not shown) is formed on the insulating film 220. Then, the insulating film 220 is etched using the resist mask, and a contact is formed on the insulating film 220. Next, a conductive film 221 is formed on the insulating film 220 and the contact hole. The materials and manufacturing methods of the insulating film 220 and the conductive film 221 are the same as those of the insulating film 120 in Embodiment 1. For details, refer to the conductive film 121. Note that the insulating film 220 is not necessarily formed. The pixel electrode may be located on the same layer as the source electrode and source wiring.

[0139] Next, a resist mask (not shown) is formed over the conductive film 221. The conductive film 221 is selectively etched to form conductive films 222a and 222b (FIG. 1 (See 8(C) and (D)). After the above etching, the resist mask is removed.

[0140] In this manner, a semiconductor device can be manufactured. It is possible to create a mask with three exposure levels: exposed, intermediately exposed, and unexposed. A single exposure and development process can produce a multi-thickness region (typically two types). A resist mask can be formed. Therefore, by using a multi-tone mask, In addition, the manufacturing method shown in this embodiment mode can reduce the number of transparent masks. The transistor 250 having a light-transmitting property and the storage capacitor portion 251 having a light-transmitting property are formed. Therefore, it is possible to connect a transistor and an element (for example, another transistor) within a pixel. The wiring that connects the signal can be formed using a material with low resistivity and high conductivity. This reduces waveform distortion and voltage drop due to wiring resistance. The semiconductor layer of the resistor 250 and the oxide semiconductor layer of the storage capacitor 251 are integrated into one island. Therefore, the layout for forming the oxide semiconductor layer is easy. Since the number of contacts can be reduced, the contact resistance can be reduced. In this embodiment, the gate wiring is formed by This section explains the case where a multi-tone mask is used in both the process of forming the source wiring and the process of forming the semiconductor substrate. However, it is possible to use the same in either the process of forming the gate wiring or the process of forming the source wiring. It's fine.

[0141] Next, another example of the semiconductor device will be described with reference to FIG. The semiconductor device has many parts in common with those in FIG. 1. Therefore, in the following, overlapping parts will be omitted. The parts that are different from the above will be omitted and only the differences will be explained. 20(B) is a cross-sectional view taken along line AB in FIG. 20(A).

[0142] 20 is different from FIG. 1 in that the light-transmitting conductive layer 109b and the light-shielding conductive layer 109c are 1 and the conductive layer 111c having a light-shielding property are laminated in this order, and the conductive layer 111c having a light-shielding property is laminated in this order. The area is increased. In addition, the contact between the pixel electrode and the conductive layer 117b is made capacitive. The wiring was formed on the conductive layer 111c having a light-shielding property. Since the details are different, a detailed description will be omitted.

[0143] By adopting such a configuration, the capacitance wiring can be formed using a material with low resistivity and high conductivity. This reduces signal waveform distortion and voltage drop due to wiring resistance. In addition, the unevenness caused by the contact holes of the pixel electrodes can cause the liquid crystal alignment to become disordered. Even if there is a problem, the light leakage can be prevented by the conductive layer 111c having the light-shielding property of the capacitance wiring. This can be done.

[0144] In addition, in the peripheral driving circuits such as the protection circuit, gate driver, and source driver, Therefore, the pixel area does not need to have a transparent transistor or capacitor. The transistors in the peripheral driver circuit are made of a material with light blocking properties. It may also be formed by

[0145] This embodiment mode can be implemented in appropriate combination with other embodiment modes.

[0146] (Embodiment 3) In this embodiment, in the display device, at least a part of the driver circuit and a pixel An example of fabricating a thin film transistor disposed in a portion will be described below.

[0147] FIG. 21 shows an example of a block diagram of an active matrix liquid crystal display device, which is an example of a display device. The display device shown in FIG. 21A has a pixel structure including a display element on a substrate 5300. a pixel portion 5301 having a plurality of pixels, a scanning line driver circuit 5302 for selecting each pixel, and a It also has a signal line driver circuit 5303 that controls input of a video signal to the pixel.

[0148] The light-emitting display device shown in FIG. 21B has a plurality of pixels each having a display element over a substrate 5400. A pixel portion 5401 for selecting each pixel, a first scanning line driver circuit 5402 for selecting each pixel, and a second scanning line driver circuit 5403 for selecting each pixel. A driver circuit 5404 and a signal line driver circuit 5405 for controlling the input of a video signal to a selected pixel 403 and

[0149] When a video signal input to a pixel of the light-emitting display device shown in FIG. 21(B) is in a digital format, When a pixel is turned on, it emits light or does not emit light by switching the transistor on or off. Therefore, gray scale display can be performed using area gray scale or time gray scale. The stacked gray scale method divides one pixel into multiple sub-pixels, and each sub-pixel is independently driven based on a video signal. The time gray scale method is a driving method that displays gray scales by moving the pixel. This is a driving method that displays gradation by controlling the period during which the light is turned on.

[0150] Light-emitting elements have a higher response speed than liquid crystal elements, making them more suitable for time gray scale modulation than liquid crystal elements. When displaying using the time gray scale method, one frame period is divided into multiple sub-frame periods. Then, in accordance with the video signal, the light emitting element of the pixel emits light in each sub-frame period. By dividing the period into multiple subframes, one frame can be The total length of the period during which the pixel emits light during the frame period can be controlled by a video signal, It is possible to display gradations.

[0151] In the light-emitting display device shown in FIG. 21B, two switching TFTs are provided for one pixel. In the case where the first scanning line which is the gate wiring of one of the switching TFTs is arranged, The signal to be input to the first scanning line driver circuit 5402 is generated by the first scanning line driver circuit 5402, and the other switching TFT A signal input to the second scanning line, which is the gate wiring of the second scanning line, is generated by a second scanning line driver circuit 5404. The example shows a signal input to the first scanning line and a signal input to the second scanning line. The signal may be generated by one scanning line driving circuit. The operation of the switching element is controlled by the number of switching TFTs that each pixel has. In this case, multiple scan lines may be provided for each pixel. The signals input to the scanning lines may all be generated by one scanning line driving circuit, or may be generated by a plurality of scanning line driving circuits. It may also be generated by the scan line driver circuit.

[0152] The thin film transistors arranged in the pixel portion of the liquid crystal display device are formed according to the first and second embodiments. In addition, since the thin film transistors shown in Embodiments 1 and 2 are n-channel TFTs, Among the driver circuits, a part of the driver circuit that can be configured with n-channel TFTs is It is formed on the same substrate as the thin film transistor.

[0153] In addition, in the light-emitting display device, the driver circuit may be configured with an n-channel TFT. A part of the driver circuit can be formed on the same substrate as the thin film transistor of the pixel portion. In addition, the signal line driver circuit and the scanning line driver circuit are formed by the n-channel TF shown in Embodiments 1 and 2. It is also possible to make it using only T.

[0154] In addition, in the peripheral driving circuits such as the protection circuit, gate driver, and source driver, Therefore, the pixel part is made of transistors and capacitors. In the peripheral drive circuit section, light is transmitted through the transistor. It's not necessary.

[0155] FIG. 22(A) shows the case where a thin film transistor is formed without using a multi-tone mask, and FIG. 22(B) shows the case where a thin film transistor is formed without using a multi-tone mask. ) is the case where a multi-tone mask is used. When a gate electrode is formed, the conductive layer 111a functions as a gate electrode, and the conductive layer 111b functions as a source electrode or a drain electrode. The conductive layers 119a and 119b, which function as inner electrodes, are formed of a conductive layer having a light-shielding property. (See FIG. 22(A)). A thin film transistor is formed using a multi-tone mask. In this case, the gate electrode, the source electrode, and the drain electrode are each a light-transmitting conductive layer. The insulating layer can be formed by laminating a conductive layer having a light-blocking property and a light-blocking conductive layer.

[0156] The above-mentioned driving circuit is not limited to liquid crystal display devices and light-emitting display devices, but may also be used in It may also be used in electronic paper, which uses electrically connected elements to drive electronic ink. Electronic paper is also called an electrophoretic display (electrophoretic display) and has the same properties as paper. It achieves the same readability, consumes less power than other display devices, and is thin and lightweight. It is possible to do this.

[0157] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0158] (Fourth embodiment) Next, a structure of a display device, which is one embodiment of a semiconductor device, will be described. As a display device, a light-emitting display device having a light-emitting element that utilizes electroluminescence The light-emitting element that utilizes electroluminescence is made of an organic compound as the light-emitting material. Generally, the former is an organic EL element, and the latter is an inorganic compound. These are called inorganic EL elements.

[0159] In an organic EL element, electrons and holes are released from a pair of electrodes by applying a voltage to the light-emitting element. are injected into the layers containing the light-emitting organic compounds, causing a current to flow. The recombination of the electrons and holes creates an excited state in the light-emitting organic compound. The excited state is then converted to the ground state, at which point light is emitted. Such a light-emitting element is called a current-excited light-emitting element.

[0160] Inorganic EL elements are divided into dispersion-type inorganic EL elements and thin-film-type inorganic EL elements depending on the element structure. Dispersion-type inorganic EL elements have a light-emitting layer in which particles of a light-emitting material are dispersed in a binder. The emission mechanism is a donor-acceptor interaction that utilizes the donor and acceptor levels. Thin-film inorganic EL devices sandwich the light-emitting layer between dielectric layers. Furthermore, this structure is sandwiched between electrodes, and the light emission mechanism utilizes the inner-shell electron transition of metal ions. In this example, the light-emitting element is an organic EL element. do.

[0161] Next, a pixel configuration and pixel operation to which digital time gray scale driving can be applied will be described. 23 is a diagram showing an example of a pixel configuration to which digital time gray scale driving can be applied. n-channel semiconductor layer (In-Ga-Zn-O non-single crystal film) is used for the channel formation region. An example in which two panel-type transistors are used in one pixel is shown.

[0162] The pixel 6400 includes a switching transistor 6401, a driving transistor 6402, It has a light emitting element 6404 and a capacitor element 6403. 01 has a gate connected to a scanning line 6406 and a first electrode (one of the source and drain electrodes) The first electrode (the other of the source electrode and the drain electrode) is connected to a signal line 6405, and the second electrode (the other of the source electrode and the drain electrode) is connected to a drive The driving transistor 6402 is connected to the gate of the driving transistor 6402. The gate is connected to a power supply line 6407 via a capacitor element 6403, and the first electrode is connected to a power supply line 640 7, and the second electrode is connected to the first electrode (pixel electrode) of the light emitting element 6404. The second electrode of the light emitting element 6404 corresponds to the common electrode 6408 .

[0163] A low power supply potential is set to the second electrode (common electrode 6408) of the light emitting element 6404. The low power supply potential is a low power supply potential with respect to the high power supply potential set to the power supply line 6407. Potential < High power supply potential. For example, GND, 0V, etc. are set as low power supply potential. The potential difference between the high power supply potential and the low power supply potential is applied to the light emitting element 6404. Then, in order to make the light emitting element 6404 emit light by passing a current through the light emitting element 6404, a high power supply potential and the low power supply potential is set to be equal to or greater than the forward threshold voltage of the light emitting element 6404. Each potential is set.

[0164] The capacitor element 6403 is omitted by substituting the gate capacitance of the driving transistor 6402. The gate capacitance of the driving transistor 6402 is determined by the channel region A capacitance may be formed between the gate electrode and the transistor.

[0165] In the case of a voltage input voltage driving method, the gate of the driving transistor 6402 is connected to The driving transistor 6402 is either fully on or off. A video signal is input, that is, the driving transistor 6402 is operated in a linear region. The driving transistor 6402 is operated in a linear region, so that the voltage of the driving transistor 6402 is higher than the voltage of the power supply line 6407. A high voltage is applied to the gate of the driving transistor 6402. The signal line 6405 is connected to A voltage equal to or greater than (power supply line voltage+Vth of the driving transistor 6402) is applied.

[0166] Furthermore, when analog grayscale driving is performed instead of digital time grayscale driving, the input of the signal is different. By doing so, the same pixel configuration as in FIG. 23 can be used.

[0167] When analog gradation driving is performed, a light emitting element 6404 is connected to the gate of a driving transistor 6402. A voltage equal to or greater than the forward voltage of the light emitting element 64 and the Vth of the driving transistor 6402 is applied. The forward voltage in 04 refers to the voltage required to achieve the desired brightness, and It should be noted that the driving transistor 6402 is designed to operate in the saturation region. By inputting an optical signal, a current can be passed through the light emitting element 6404. In order to operate the transistor 6402 in the saturation region, the potential of the power supply line 6407 is The potential of the light emitting element is made higher than the gate potential of the capacitor 6402. A current corresponding to a video signal is passed through 6404, enabling analog gradation driving.

[0168] Note that the pixel configuration shown in Fig. 23 is not limited to this. For example, A switch, a resistor, a capacitor, a transistor, a logic circuit, or the like may be added.

[0169] Next, the configuration of the light emitting element will be explained with reference to FIGS. 24(A), 24(B), and 24(C). Here, the case where the driving TFT is the transistor 150c shown in FIG. The cross-sectional structure of the pixel will be explained below. The TFTs 7001, 7011, and 7021, which are driving TFTs used in semiconductor devices, are implemented It can be fabricated in the same way as the transistors shown in Forms 1 and 2, and is an In-Ga-Zn-O based non-single crystal film. The thin film transistor has excellent electrical properties and includes a semiconductor layer.

[0170] The light emitting element only needs to have at least one of the anode and cathode transparent in order to extract light. Then, a thin film transistor and a light emitting element are formed on the substrate, and light is taken from the surface opposite to the substrate. Top emission, bottom emission, and top emission. There are light-emitting devices with a double-sided emission structure in which light is emitted from the side surface. The present invention can also be applied to a light emitting element with an injection structure.

[0171] A light emitting element with a top emission structure will be described with reference to FIG.

[0172] 24A, a TFT 7001, which is a driving TFT, is the transistor 150 shown in FIG. c, and the pixel when the light emitted from the light emitting element 7002 passes through the anode 7005 side. 24(A) shows a cross-sectional view of a cathode 7003 of a light-emitting element 7002 and a driving TFT. The TFT 7001 is electrically connected to the cathode 7003, and the light-emitting layer 7004 and the anode 7005 are connected to the cathode 7003. The cathode 7003 has a small work function and reflects light. Various conductive materials can be used, such as Ca, Al, CaF, and MgA. The light-emitting layer 7004 may be composed of a single layer or multiple layers. It can be configured so that several layers are stacked. In this case, an electron injection layer, an electron transport layer, a light-emitting layer, a hole transport layer, and a hole injection layer are formed on the cathode 7003. It is not necessary to provide all of these layers. The anode 7005 is a light-transmitting layer. The insulating film is formed using a light-transmitting conductive material, for example, indium oxide containing tungsten oxide. Indium oxide, indium zinc oxide with tungsten oxide, indium titanium oxide oxide, indium tin oxide containing titanium oxide, indium tin oxide (hereinafter referred to as ITO) ), indium zinc oxide, indium tin oxide doped with silicon oxide, etc. A conductive film having the above structure may be used.

[0173] The region where the light-emitting layer 7004 is sandwiched between the cathode 7003 and the anode 7005 is the light-emitting element 7002. In the case of the pixel shown in FIG. 24(A), the light emitted from the light emitting element 7002 is The light is emitted toward the anode 7005 as shown by the mark.

[0174] Note that the gate electrode provided over the oxide semiconductor layer in the driver circuit is made of the same material as the cathode 7003. Forming the film from a material is preferable because it simplifies the process.

[0175] Next, a light emitting element with a bottom emission structure will be described with reference to FIG. 12, and the light emitted from the light-emitting element 7012 is 24(B) shows a cross-sectional view of a pixel when the driving T The light-emitting element 701 is formed on a light-transmitting conductive film 7017 electrically connected to the FT 7011. A cathode 7013 of the second type is formed, and a light-emitting layer 7014 and an anode 7015 are formed on the cathode 7013. In addition, when the anode 7015 is light-transmitting, the anode 7015 is covered with the A shielding film 7016 for reflecting or blocking light may be formed. As in the case of FIG. 24(A), various materials can be used as long as they are conductive films with small work functions. However, the film thickness should be such that light can be transmitted (preferably about 5 nm to 30 nm). For example, an aluminum film having a thickness of 20 nm is used as the cathode 7013. The light-emitting layer 7014 can be formed of a single layer, as in FIG. The anode 701 may be formed by laminating a plurality of layers. 5 does not need to transmit light, but similar to FIG. 24(A), a conductive material having light-transmitting properties can be used. The shielding film 7016 can be formed by using, for example, a metal that reflects light. However, it is not limited to a metal film. For example, a resin containing a black pigment can be used. You can also be there.

[0176] The region where the light-emitting layer 7014 is sandwiched between the cathode 7013 and the anode 7015 is the light-emitting element 7012. In the case of the pixel shown in FIG. 24B, the light emitted from the light-emitting element 7012 corresponds to The light is emitted toward the cathode 7013 as shown by the arrow.

[0177] Note that the gate electrode provided over the oxide semiconductor layer in the driver circuit is made of the same material as the cathode 7013. Forming the film from a material is preferable because it simplifies the process.

[0178] Next, a light emitting element with a dual emission structure will be described with reference to FIG. Then, on the conductive film 7027 having light-transmitting properties and electrically connected to the driving TFT 7021, A cathode 7023 of the light-emitting element 7022 is formed as a film. A light-emitting layer 7024 is formed on the cathode 7023. The cathode 7023 is laminated in the same manner as in FIG. Various materials can be used as long as the conductive film has a small electrical conductivity. For example, Al having a thickness of 20 nm is used as the cathode 7023. The light-emitting layer 7024 can be formed of a single layer, as in FIG. The anode 7025 may be a single layer or may be a laminate of multiple layers. 24A, the light-transmitting conductive material can be used.

[0179] The overlapping portion of the cathode 7023, the light-emitting layer 7024, and the anode 7025 is the light-emitting element 70. In the case of the pixel shown in FIG. 24(C), the light emitted from the light emitting element 7022 is emitted to both the anode 7025 side and the cathode 7023 side as shown by the arrows.

[0180] Note that the gate electrode provided over the oxide semiconductor layer in the driver circuit has the same structure as the conductive film 7027. It is preferable to use oxide semiconductor materials in the driver circuit because this simplifies the manufacturing process. The gate electrode provided on the conductive layer is laminated using the same material as the conductive film 7027 and the cathode 7023. This not only simplifies the process but also reduces wiring resistance by stacking. This is preferable.

[0181] Although organic EL elements have been described as light-emitting elements here, inorganic EL elements can also be used as light-emitting elements. It is also possible to provide an L element.

[0182] In this embodiment, a thin film transistor (driving TFT) for controlling the driving of a light emitting element is used. In the example shown, the light emitting element is electrically connected to the driving TFT. A current control TFT may be connected.

[0183] The semiconductor device described in this embodiment mode has the same structure as that shown in FIGS. The present invention is not limited to the configuration shown, and various modifications based on the disclosed technical idea are possible. be.

[0184] Next, the upper surface and the lower surface of a light-emitting display panel (also referred to as a light-emitting panel), which corresponds to one mode of a semiconductor device, The cross section will be explained using Figures 25(A) and 25(B). Figure 25(A) shows the first The thin film transistor and the light emitting element formed on the substrate are sandwiched between the second substrate and the substrate by a sealing material. 25(B) is a top view of the panel sealed by the HI in FIG. 25(A). This corresponds to a cross-sectional view.

[0185] A pixel portion 4502, a signal line driver circuit 4503a, and a signal line driver circuit 4504 are provided on a first substrate 4501. 3b and the scanning line driver circuits 4504a and 4504b. In addition, a pixel portion 4502, signal line driver circuits 4503a and 4503b, and A second substrate 4506 is provided on the scanning line driver circuits 4504a and 4504b. The pixel portion 4502, the signal line driver circuits 4503a and 4503b, and the scanning line driver circuit 45 4504a and 4504b are a first substrate 4501, a sealing material 4505, and a second substrate 4506. The seal is sealed together with the filler 4507 by the sealant. Highly airtight protective film with little outgassing (lamination film, UV curable resin film) It is preferable to package (enclose) the product in a protective film (such as a film) or a cover material.

[0186] In addition, a pixel portion 4502, a signal line driver circuit 4503a, 4503b and the scanning line driver circuits 4504a and 4504b have a plurality of thin film transistors. In FIG. 25B, a thin film transistor 4510 included in a pixel portion 4502 and A thin film transistor 4509 included in the signal line driver circuit 4503a is shown as an example. The transistors 4509 and 4510 use an In-Ga-Zn-O non-single crystal film as a semiconductor layer. The highly reliable thin film transistors described in Embodiments 1 to 3 can be applied.

[0187] In addition, in the peripheral driving circuits such as the protection circuit, gate driver, and source driver, Therefore, in the pixel portion 4502, the transistor The transistors and capacitors in the peripheral driver circuit are formed using a light-transmitting material. It may be formed of a material having light blocking properties.

[0188] Further, 4511 corresponds to a light-emitting element, and a first electrode which is a pixel electrode of the light-emitting element 4511 is The electrode layer 4517 is electrically connected to the source electrode layer or the drain electrode layer of the thin film transistor 4510. The light-emitting element 4511 is configured by a first electrode layer 4517, an electric field generating layer 4518, and a second electrode layer 4519. The structure shown in this embodiment is a stacked structure of the light emitting layer 4512 and the second electrode layer 4513. The light emitting element 4511 may be arranged in accordance with the direction of light to be extracted from the light emitting element 4511. The configuration of 1 can be changed as needed.

[0189] The partition wall 4520 is formed using an organic resin film, an inorganic insulating film, or organic polysiloxane. In particular, a photosensitive material is used to form an opening on the first electrode layer 4517, and the sidewall of the opening It is preferable to form the inclined surface so that the inclined surface has a continuous curvature.

[0190] The electroluminescent layer 4512 may be composed of a single layer or a plurality of layers stacked. It doesn't matter whether it's done or not.

[0191] The second electrode layer is formed to prevent oxygen, hydrogen, moisture, carbon dioxide, and the like from entering the light-emitting element 4511. A protective film may be formed on the partition wall 4513 and the partition wall 4520. The protective film may be a silicon nitride film, A silicon nitride oxide film, a DLC film, or the like can be formed.

[0192] In addition, signal line driver circuits 4503a and 4503b, scanning line driver circuits 4504a and 4504b Various signals and potentials applied to the pixel portion 4502 are transmitted through the FPC 4518a, 4518b, and It is supplied by b.

[0193] In this embodiment, the connection terminal electrode 4515 is connected to the first electrode layer 4 The terminal electrode 4516 is formed from the same conductive film as the thin film transistors 4509 and 517. The source electrode layer and the drain electrode layer 510 are formed from the same conductive film.

[0194] The connection terminal electrode 4515 is connected to the terminal of the FPC 4518a via the anisotropic conductive film 4519. are electrically connected to each other.

[0195] The second substrate is not transparent to light, and is positioned in the direction of light extraction from the light emitting element 4511. In this case, glass plates, plastic plates, polyester films or A light-transmitting material such as an acrylic film is used.

[0196] In addition to inert gases such as nitrogen and argon, filler 4507 can also be used as UV-curable resin. It can be made of oil or thermosetting resin, and PVC (polyvinyl chloride), acrylic, Polyimide, epoxy resin, silicone resin, PVB (polyvinyl butyral) or EV A (ethylene vinyl acetate) can be used.

[0197] If necessary, a polarizing plate or a circular polarizing plate (including an elliptical polarizing plate) may be provided on the light-emitting surface of the light-emitting element. Optical films such as retardation plates (λ / 4 plates, λ / 2 plates) and color filters may be provided as appropriate. In addition, an anti-reflection film may be provided on the polarizing plate or the circular polarizing plate. Anti-glare treatment can be applied to diffuse reflected light and reduce glare.

[0198] The signal line driver circuits 4503a and 4503b and the scanning line driver circuits 4504a and 4504b are A single crystal semiconductor substrate or a polycrystalline semiconductor film is formed on an insulating substrate. Alternatively, the signal line driver circuit may be implemented as a drive circuit formed by a thin film. Alternatively, only a part of the scanning line driver circuit or only a part of the scanning line driver circuit may be separately formed and mounted. This embodiment is not limited to the configurations of FIGS. 25(A) and 25(B).

[0199] Through the above steps, a light-emitting display device can be manufactured at reduced costs.

[0200] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0201] (Embodiment 5) Next, another structure of a display device, which is one embodiment of a semiconductor device, will be described. A liquid crystal display device having a liquid crystal element will be described as a display device.

[0202] First, the top and cross-sectional views of a liquid crystal display panel (also called a liquid crystal panel), which is one type of liquid crystal display device, will be described. The surface will be explained using Figures 26(A1), 26(A2), and 26(B). 26(A1) and 26(A2) show the structure shown in the first to third embodiments formed on a first substrate 4001. Thin film transistor 4010 including an In-Ga-Zn-O based non-single crystal film as a semiconductor layer 4011 and a liquid crystal element 4013 are disposed between a second substrate 4006 and a sealant 4005. 26(A1), 26(A2), and 26(B) are top views of the sealed panel. 2) corresponds to the cross section at MN.

[0203] A pixel portion 4002 and a scanning line driver circuit 4004 are provided on a first substrate 4001. In this way, a sealing material 4005 is provided. A second substrate 4006 is provided on the path 4004. The line driver circuit 4004 is made up of a first substrate 4001, a sealing material 4005, and a second substrate 4006. The first substrate 4001 is sealed together with the liquid crystal layer 4008. In a region different from the region surrounded by the material 4005, a single crystal is formed on a separately prepared substrate. A signal line driver circuit 4003 formed of a semiconductor film or a polycrystalline semiconductor film is mounted.

[0204] The method of connecting the separately formed drive circuit is not particularly limited, and may be a COG method, Wire bonding or TAB method can be used. is an example of mounting a signal line driver circuit 4003 by the COG method, and FIG. 26(A2) shows This is an example in which a signal line driver circuit 4003 is mounted by the TAB method.

[0205] In addition, a pixel portion 4002 and a scanning line driver circuit 4004 are provided on a first substrate 4001. 26(B), the thin film transistor included in the pixel portion 4002 a thin film transistor 4010 and a thin film transistor 401 included in a scanning line driver circuit 4004 An insulating layer 4021 is provided on the thin film transistors 4010 and 4011. The thin film transistors 4010 and 4011 are made of In-Ga-Zn-O based non-single crystal The thin film transistors shown in Embodiments 1 to 3 including the film as a semiconductor layer can be applied. do.

[0206] In addition, in the peripheral driving circuits such as the protection circuit, gate driver, and source driver, Therefore, in the pixel portion 4002, the transistor does not need to transmit light. The transistors and capacitors in the peripheral driver circuit are formed using a light-transmitting material. It may be formed of a material having light blocking properties.

[0207] The pixel electrode 4030 of the liquid crystal element 4013 is electrically connected to the thin film transistor 4010. The counter electrode layer 4031 of the liquid crystal element 4013 is electrically connected to the second substrate 400. The pixel electrode 4030, the counter electrode layer 4031, and the liquid crystal layer 4008 are overlapped. The portion where the pixel electrode 4030 and the counter electrode layer 4031 are formed corresponds to the liquid crystal element 4013. The insulating layers 4032 and 4033 functioning as alignment films are provided on the insulating layer 4031. A liquid crystal layer 4008 is sandwiched between 4032 and 4033 .

[0208] In the pixel section 4002, the grid-like wiring portion does not transmit light, but the other portions transmit light. Furthermore, the gap between each pixel electrode can be increased. A gap is necessary, and no electric field is applied to the liquid crystal in the gap. Therefore, the grid-like wiring part is made into a black matrix. It can be used.

[0209] The first substrate 4001 and the second substrate 4006 may be made of glass or metal (typically, stainless steel). Stainless steel, ceramics, and plastics can be used. , FRP (Fiberglass-Reinforced Plastics) board, PV F (polyvinyl fluoride) film, polyester film or acrylic resin film Aluminum foil can also be used with PVF film or polyester film. A sheet sandwiched between films can also be used.

[0210] 4035 is a columnar spacer obtained by selectively etching the insulating film. In order to control the distance (cell gap) between the pixel electrode 4030 and the counter electrode layer 4031 A spherical spacer may be used. The counter electrode layer 4031 is , which is electrically connected to a common potential line provided on the same substrate as the thin film transistor 4010. The common connection portion is used to connect the counter electrode layer 403 via conductive particles disposed between the pair of substrates. The conductive particles can electrically connect the sealing material 400 to the common potential line. Include in 5.

[0211] Alternatively, a liquid crystal that exhibits a blue phase without using an alignment film may be used. The blue phase is one of the liquid crystal phases. When the temperature of cholesteric liquid crystal is increased, the phase immediately transitions from the cholesteric phase to the isotropic phase. The blue phase appears only in a narrow temperature range, so the temperature range needs to be improved. In order to achieve this, a liquid crystal composition containing 5% by weight or more of a chiral agent is used for the liquid crystal layer 4008. The liquid crystal composition containing the liquid crystal exhibiting the blue phase and the chiral agent has a response speed of 10 μs to It is optically isotropic, requiring no alignment treatment, and has little viewing angle dependency. stomach.

[0212] Although the liquid crystal display device shown in this embodiment is an example of a transmissive liquid crystal display device, a reflective liquid crystal display device may also be used. The present invention can be applied to both display devices and semi-transmissive liquid crystal display devices.

[0213] In addition, in the liquid crystal display device described in this embodiment mode, a polarizing plate is provided on the outer side (viewing side) of the substrate, and In the example shown in Fig. 1, a colored layer and an electrode layer used for a display element are provided in this order, but the polarizing plate is provided on the inner side of the substrate. The laminated structure of the polarizing plate and the colored layer is not limited to the present embodiment, and the polarizing plate and the colored layer may be provided. The black matrix may be appropriately set depending on the material of the colored layer and the manufacturing process conditions. A light-shielding film that functions as a light-shielding film may be provided.

[0214] In this embodiment, in order to reduce the surface unevenness of the thin film transistor, In order to improve the reliability of the thin film transistors obtained in the first to third embodiments, The insulating layer 402 is covered with an insulating layer 4021 which functions as a planarization insulating film. The protective film 1 can be formed in a single layer or a laminated structure of two or more layers. It is designed to prevent the intrusion of polluting impurities such as floating organic matter, metals, and water vapor. The protective film is preferably a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or the like, which is formed by sputtering. Bare film, silicon nitride oxide film, aluminum oxide film, aluminum nitride film, aluminum oxynitride film The insulating film may be formed of a single layer or a stack of aluminum nitride oxide films. Although the protective film is formed by sputtering, it is not limited to this and may be formed by other methods such as plasma CVD. The film may be formed by various methods.

[0215] The protective film can be formed of an insulating layer having a laminated structure. In this case, a silicon oxide film is formed as the first layer of the protective film by, for example, sputtering. When a silicon oxide film is used as the source electrode layer and the drain electrode layer, the aluminum film used as the source electrode layer and the drain electrode layer It is effective in preventing hillocks on rubber films.

[0216] Furthermore, as the second layer of the protective film, a silicon nitride film is formed by, for example, sputtering. When a silicon nitride film is used as the gate electrode, mobile ions such as sodium ions penetrate into the semiconductor region, and the T It is possible to suppress changes in the electrical characteristics of the FT.

[0217] After forming the protective film, the semiconductor layer may be annealed (at 300°C to 400°C). In addition, the back gate is formed after the protective film is formed.

[0218] An insulating layer 4021 is formed as a planarization insulating film. Heat-resistant organic compounds such as amide, acrylic, benzocyclobutene, polyamide, and epoxy. In addition to the above organic materials, low-k materials can also be used. , siloxane resin, PSG (phosphorus glass), BPSG (borophosphorus glass), etc. In addition, by stacking multiple insulating films made of these materials, it is possible to obtain an insulating layer. 4021 may be formed.

[0219] Siloxane-based resin is a Si-OS compound formed using siloxane-based materials as starting materials. Siloxane resins contain hydrogen as a substituent, as well as fluorine and alkyl groups. The alkyl group may have at least one of an alkyl group, an alkyl group, an alkyl group, and an aryl group.

[0220] The method for forming the insulating layer 4021 is not particularly limited, and may be a sputtering method, an SOG method, or the like, depending on the material. , spin coating, dip coating, spray coating, droplet ejection method (inkjet method, screen printing, offset printing, etc.), doctor knife, roll coater, curtain coater, knife When the insulating layer 4021 is formed using a material liquid, The semiconductor layer may be annealed (at 300°C to 400°C) at the same time as the step of annealing. By combining the firing process of the edge layer 4021 with the annealing of the semiconductor layer, semiconductor devices can be efficiently manufactured. It becomes possible to do this.

[0221] The pixel electrode 4030 and the counter electrode layer 4031 are made of indium oxide containing tungsten oxide. Indium zinc oxide with tungsten oxide, indium oxide with titanium oxide, acid Indium tin oxide containing titanium dioxide, indium tin oxide (hereinafter referred to as ITO), Translucent conductive materials such as indium zinc oxide and indium tin oxide doped with silicon oxide Conductive materials can be used.

[0222] The pixel electrode 4030 and the counter electrode layer 4031 are made of a conductive polymer ( The conductive composition may be used to form the conductive layer. The pixel electrode has a sheet resistance of 10000Ω / □ or less and a light transmittance of 550nm. It is preferable that the resistivity of the conductive polymer contained in the conductive composition is 70% or more. It is preferable that the resistivity is 0.1 Ω·cm or less.

[0223] As the conductive polymer, a so-called π-electron conjugated conductive polymer can be used. For example, polyaniline or its derivatives, polypyrrole or its derivatives, polythiophene or or a derivative thereof, or a copolymer of two or more of these.

[0224] A signal line driver circuit 4003 and a scanning line driver circuit 4004 or a pixel section 4 Various signals and potentials applied to 002 are supplied from FPC4018.

[0225] In this embodiment, the connection terminal electrode 4015 is connected to the pixel electrode 403 of the liquid crystal element 4013. The terminal electrode 4016 is formed from the same conductive film as the thin film transistors 4010 and 401. The source electrode layer and the drain electrode layer are formed of the same conductive film as the source electrode layer and the drain electrode layer of the first transistor.

[0226] The connection terminal electrode 4015 is connected to the terminal of the FPC 4018 via the anisotropic conductive film 4019. are electrically connected.

[0227] In addition, in FIG. 26(A1) and FIG. 26(A2), a signal line driver circuit 4003 is separately formed. 10, an example in which the first substrate 4001 is mounted is shown, but this embodiment is not limited to this configuration. The scanning line driver circuit may be formed separately and mounted, or may be mounted as part of the signal line driver circuit or Alternatively, only a part of the scanning line driving circuit may be separately formed and mounted.

[0228] FIG. 27 shows a liquid crystal display module constructed as a semiconductor device using a TFT substrate 2600. An example is shown.

[0229] FIG. 27 shows an example of a liquid crystal display module, in which a TFT substrate 2600 and an opposing substrate 2601 are connected. The substrate is fixed by a bonding material 2602, and a pixel portion 2603 including a TFT and the like and a liquid crystal layer are disposed between the substrate and the bonding material 2602. A display element 2604 and a colored layer 2605 are provided to form a display area. is required for color display, and in the case of the RGB method, it corresponds to each color of red, green, and blue. A colored layer is provided corresponding to each pixel. On the outside, a polarizing plate 2606, a polarizing plate 2607, and a diffusion plate 2613 are arranged. It is composed of a cathode ray tube 2610 and a reflector 2611, and a circuit board 2612 is a flexible wiring board. The wiring board 2609 is connected to the wiring circuit section 2608 of the TFT substrate 2600, and the controller It also incorporates external circuits such as a polarizing plate and a power supply circuit. The layers may be laminated with a retardation film interposed therebetween.

[0230] The LCD module is available in TN (Twisted Nematic) mode, IPS (In-Plane Switching) mode, n-Plane-Switching mode, FFS (Fringe Field Switching) Switching mode, MVA (Multi-domain Vertical A alignment) mode, PVA(Patterned Vertical Alignment) mode, PVA(Patterned Vertical Alignment) mode nment), ASM(Axially Symmetric aligned Mic ro-cell) mode, OCB(Optical Compensated Bire) fringence mode, FLC (Ferroelectric Liquid Crystal Crystal mode, AFLC (AntiFerroelectric Liquid Crystal) can be used.

[0231] Through the above steps, a liquid crystal display device can be manufactured at reduced manufacturing costs.

[0232] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0233] (Embodiment 6) Next, we will explain electronic paper, which is one type of semiconductor device. Achieve the same readability while consuming less power than other display devices, and being thinner and lighter. It is possible.

[0234] FIG. 28 shows an active matrix electronic paper as one mode of a semiconductor device. The thin film transistor 581 used in the pixel portion of the semiconductor device is the same as that shown in the above embodiment. It can be fabricated in the same way as the thin-film transistor in the pixel section, and the In-Ga-Zn-O system non-single crystal film is used as a semiconductor. The thin film transistor includes a gate insulating layer.

[0235] The electronic paper shown in FIG. 28 is an example of a display device that uses a twisting ball display method. The istball display method is an electrode layer that uses spherical particles painted in black and white as display elements. and a first electrode layer and a second electrode layer, This is a method of displaying by controlling the orientation of spherical particles by creating a potential difference.

[0236] The thin film transistor 581 is a thin film transistor with a bottom gate structure, and the source electrode layer The drain electrode layer is in contact with the first electrode layer 587 through an opening formed in the insulating layer 585. The first electrode layer 587 and the second electrode layer 588 are electrically connected to each other. 0a and white area 590b, and includes a cavity 594 filled with liquid therearound. Spherical particles 589 are provided, and the periphery of the spherical particles 589 is filled with a filler 595 such as resin. (See Figure 28.)

[0237] Also, instead of the twist ball, an electrophoretic display element can be used. A liquid containing positively charged white particles and negatively charged black particles, with a diameter of 10 μm or more. Microcapsules of about 200 μm are used. When an electric field is applied to the microcapsules by the first and second electrode layers, The white particles and the black particles move in opposite directions, allowing the display to be white or black. The display element that applies this principle is the electrophoretic display element. It has a higher reflectivity than other light sources, so auxiliary lights are not required, and it consumes less power and is suitable for use in dimly lit areas. The display can be recognized even when there is no power supply to the display. Even if the image is displayed, it can be maintained, so the power supply source (e.g., radio wave Even if you move the e-paper away from the source, you can still save the displayed image. It becomes possible.

[0238] Through the above steps, electronic paper can be produced at reduced manufacturing costs.

[0239] This embodiment mode can be implemented by being appropriately combined with the configurations described in other embodiments. is.

[0240] (Embodiment 7) The semiconductor device according to the disclosed invention can be applied to various electronic devices (including gaming machines). The electronic device can be, for example, a television device (television or television receivers), computer monitors, digital cameras, digital video cameras digital photo frames, mobile phones (also called mobile phones or mobile phone devices), portable Examples include game machines, mobile information terminals, sound reproduction devices, and large game machines such as pachinko machines. do.

[0241] 29(A) shows an example of a mobile information terminal device 9200. The 00 has a built-in computer and is capable of performing various data processing. Such portable information terminal devices 9200 include PDAs (Personal Digital Assistants) Assistance).

[0242] The mobile information terminal device 9200 is composed of two housings, a housing 9201 and a housing 9203. The housing 9201 and the housing 9203 are foldably connected to each other at a connecting portion 9207. A display unit 9202 is incorporated in a housing 9201, and a keyboard 9203 is incorporated in a housing 9203. Of course, the configuration of the mobile information terminal device 9200 is not limited to the above. It is sufficient that the thin film transistor has a back gate electrode. The drive circuit and other auxiliary equipment can be mounted on the same board. By forming a pixel section, manufacturing costs are reduced and thin film transistors with high electrical properties can be used. It is possible to realize a portable information terminal device having such a function.

[0243] FIG. 29B shows an example of a digital video camera 9500. The META 9500 has a display unit 9503 built into a housing 9501, and various operation units are also installed. The configuration of the digital video camera 9500 is not particularly limited, and at least It is sufficient that the device has a thin film transistor having a back gate electrode, and other auxiliary equipment The driving circuit and the pixel section are formed on the same substrate. This reduces manufacturing costs and allows for the development of digital video devices with thin film transistors with excellent electrical properties. This makes it possible to realize a video camera.

[0244] FIG. 29C shows an example of a mobile phone 9100. The mobile phone 9100 has a housing It consists of two housings, 9102 and housing 9101, and is foldable by connecting part 9103. The display unit 9104 is incorporated in the housing 9102. The body 9101 is provided with operation keys 9106. The mobile phone 9100 is configured as follows: There is no particular limitation, but the configuration includes at least a thin film transistor having a back gate electrode. Other auxiliary equipment may be provided as appropriate. By forming the operating circuit and pixel section, manufacturing costs are reduced, and thin film transistors with high electrical properties are used. It is possible to realize a mobile phone having a register.

[0245] FIG. 29(D) shows an example of a portable computer 9800. The device 800 includes a housing 9801 and a housing 9804 that are connected in an openable and closable manner. The display unit 9802 is built into the housing 9801, and the housing 9801 is equipped with a keyboard 9803, etc. The configuration of the computer 9800 is not particularly limited, and at least the back gate electrode Any configuration is possible as long as it includes a thin film transistor having the above structure, and other auxiliary equipment is appropriately provided. By forming the driver circuit and the pixel portion on the same substrate, the manufacturing cost can be reduced. This makes it possible to realize a computer having thin film transistors with reduced noise and high electrical properties.

[0246] FIG. 30(A) shows an example of a television device 9600. The display unit 9603 is incorporated in the housing 9601. In this case, the housing 9601 is supported by a stand 9605. This shows a configuration in which the above is supported.

[0247] The television device 9600 can be operated using an operation switch on the housing 9601 or a separate remote control. This can be done by the remote control operation device 9610. The channel and volume can be controlled by the 9609, and the information displayed on the display 9603 is In addition, the remote control operation device 9610 can operate the video. A display portion 9607 for displaying information output from 9610 may be provided.

[0248] The television device 9600 is configured to include a receiver, a modem, and the like. It can receive more general TV broadcasts and can also receive them via wired or wireless modems. By connecting to a communication network, it can be one-way (sender to receiver) or two-way. It is also possible to communicate information (between a sender and a receiver, or between receivers).

[0249] FIG. 30(B) shows an example of a digital photo frame 9700. The photo frame 9700 has a display unit 9703 built into a housing 9701. The unit 9703 is capable of displaying various images, for example, images taken with a digital camera. By displaying the image data, it can function like a normal photo frame.

[0250] The Digital Photo Frame 9700 has an operation panel, external connection terminals (USB terminal, US A terminal that can be connected to various cables such as B cable, etc., and a recording medium insertion section. These components may be incorporated on the same surface as the display unit, but they may be incorporated on the side or back. It is preferable to have a recording medium for a digital photo frame as it improves the design. A memory that stores image data taken with a digital camera is inserted into the body insertion section. The image data can be captured and the captured image data can be displayed on the display portion 9703 .

[0251] The digital photo frame 9700 may also be configured to be capable of transmitting and receiving information wirelessly. It is also possible to configure the device so that desired image data can be wirelessly acquired and displayed.

[0252] FIG. 31(A) shows an example of a mobile phone 1000 different from the mobile phone of FIG. 29(C). The mobile phone 1000 includes a display unit 1002 built into a housing 1001, an operation unit 1003, a display unit 1004, a display unit 1005, a display unit 1006, a display unit 1007, a display unit 1008, a display unit 1009, a display unit 1010, a display unit 1011, a display unit 1012, a display unit 1013, a operation button 1003, external connection port 1004, speaker 1005, microphone 1006, etc. It is prepared.

[0253] The mobile phone 1000 shown in FIG. 31(A) displays information by touching the display unit 1002 with a finger or the like. In addition, operations such as making a phone call or sending an email can be performed using the display unit 1. This can be done by touching 002 with a finger or the like.

[0254] The screen of the display unit 1002 has three main modes. The first is a display mode that mainly displays images. The first mode is a display mode, and the second mode is an input mode that mainly inputs information such as characters. This is a display + input mode that combines two modes: display mode and input mode.

[0255] For example, when making a call or creating an email, the display unit 1002 is used to input characters. This is the main character input mode, and you can input characters displayed on the screen. It is preferable to display a keyboard or number buttons on most of the screen of the display unit 1002. Desirable.

[0256] In addition, the mobile phone 1000 may include a sensor for detecting tilt, such as a gyro or an acceleration sensor. By providing a detection device having the above configuration, the orientation of the mobile phone 1000 (portrait or landscape) can be determined and the display The screen display of the display unit 1002 can be automatically switched.

[0257] The screen mode can be switched by touching the display unit 1002 or by operating the housing 1001. This is done by operating the button 1003. Also, depending on the type of image displayed on the display unit 1002, For example, if the image signal to be displayed on the display unit is a video signal, If it is data, the display mode is switched to, and if it is text data, the input mode is switched to.

[0258] In the input mode, the optical sensor of the display unit 1002 detects a signal and displays it. If there is no input by touch operation of the part 1002 for a certain period of time, the screen mode is changed to the input mode. Alternatively, the display mode may be switched from the normal mode to the display mode.

[0259] The display unit 1002 can also function as an image sensor. By touching the palm or fingers to the sensor 02, the palm print, fingerprint, etc. can be captured and identity authentication can be performed. In addition, the display unit may be equipped with a backlight that emits near-infrared light or a sensor that emits near-infrared light. By using a scanning light source, it is also possible to capture images of finger veins, palm veins, etc.

[0260] FIG. 31B is also an example of a mobile phone. The mobile phone in FIG. 31B has a housing 9411. A display device 9410 including a display portion 9412 and an operation button 9413 is mounted on a housing 9401. An operation button 9402, an external input terminal 9403, a microphone 9404, a speaker 9405, and The communication device 9400 includes a light emitting unit 9406 that emits light when an incoming call is received, and has a display function. The display device 9410 can be attached to and detached from the communication device 9400 having a telephone function in two directions as shown by the arrows. Therefore, the display device 9410 and the communication device 9400 can be attached to each other with their short axes facing each other. The display device 9410 and the communication device 9400 can be attached to each other with their long axes facing each other. When only the function is required, the display device 9410 is removed from the communication device 9400. The communication device 9400 and the display device 9410 can be used independently. Images or input information can be sent and received via wired or wireless communication, and each can be recharged with a battery. Having Terry. [Explanation of symbols]

[0261] 100 boards 101 Oxide semiconductor film 102 Gate insulating film 102a Resist mask 103a Oxide semiconductor layer 103b Oxide semiconductor layer 103c Oxide semiconductor layer 103d Oxide semiconductor layer 103e Oxide semiconductor layer 104 Gate insulating film 105 Conductive film 106 Conductive film 107a Resist mask 107b Resist mask 108a conductive layer 108b Conductive layer 109a conductive layer 109b Conductive layer 109c Conductive layer 109d conductive layer 110 Resist mask 111a Conductive layer 111b Conductive layer 111c conductive layer 112 insulating film 113 Conductive film 114 Conductive film 115 Conductive film 115a Resist mask 115b resist mask 116a conductive layer 1116b Conductive layer 116b Conductive layer 117a Conductive layer 117b Conductive layer 117c conductive layer 117d conductive layer 117e conductive layer 117f conductive layer 117g conductive layer 118 Resist Mask 119a Conductive layer 119b Conductive layer 119c conductive layer 120 insulating film 121 Conductive film 122a conductive layer 122b Conductive layer 126 Contact Hole 127 Channel Protection Layer 150 transistors 150a transistor 150b transistor 150c transistor 151a Holding capacity section 151b Holding capacity section 151c Holding capacity section 151d Holding capacity section 180 Gray Tone Mask 185 Halftone Mask 200 boards 203a Oxide semiconductor layer 204 Gate insulating film 205 Conductive Film 206 Conductive Film 207a Resist mask 207b Resist mask 208a conductive layer 208b Conductive layer 209a Conductive layer 209b Conductive layer 210 Resist mask 211 Conductive layer 211a conductive layer 211b Conductive layer 212 insulating film 213 Conductive Film 214 Conductive film 215a Resist mask 215b Resist mask 216a conductive layer 216b Conductive layer 217a Conductive layer 217b Conductive layer 218 Resist mask 219a Conductive layer 220 insulating film 221 Conductive Film 222a Conductive film 250 transistors 251 Holding capacity section 300 boards 301a Semi-transparent layer 301b Semi-transparent layer 301c light shielding layer 302 Substrate 303a Light shielding layer 303b Semi-transparent layer 307 Oxide semiconductor layer 308 Oxide semiconductor layer 310a conductive layer 310b conductive layer 311a Oxide semiconductor layer 311b Oxide semiconductor layer 313 Barrier Film 314 Transparent conductive layer 315 Channel Protection Layer 323 Conductive Film 350 Thin-Film Transistors 400 boards 401 Light blocking part 402 Diffraction grating section 403 Gray Tone Mask 411 Substrate 412 Semi-transparent part 413 Light blocking part 414 Halftone Mask 581 Thin-film transistor 585 Insulation Layer 587 Electrode layer 588 Electrode layer 589 Spherical particles 594 Cavity 595 Filling material 1000 mobile phones 1001 Case 1002 Display section 1002 Display section 1003 Operation button 1004 External connection port 1005 Speaker 1006 Mike 2600 TFT substrate 2601 Opposing substrate 2602 Sealing material 2603 Pixel section 2604 Display element 2605 Colored layer 2606 Polarizing plate 2607 Polarizing plate 2608 Wiring circuit section 2609 Flexible wiring board 2610 cold cathode tube 2611 Reflector 2612 Circuit Board 2613 Diffuser 301a Semi-transparent layer 301c light shielding layer 303a Light shielding layer 303b Semi-transparent layer 590a black area 590b White area 4001 board 4002 Pixel section 4003 Signal line driver circuit 4004 Scanning line driver circuit 4005 Sealing material 4006 board 4008 Liquid crystal layer 4010 Thin Film Transistor 4011 Thin-film transistor 4013 Liquid crystal element 4015 Connection terminal electrode 4016 Terminal electrode 4018 FPC 4019 Anisotropic conductive film 4020 Insulation layer 4021 Insulation layer 4030 pixel electrode 4031 Counter electrode layer 4032 Insulation layer 4501 Circuit Board 4502 Pixel section 4503a Signal line driver circuit 4504a Scanning line driver circuit 4505 Sealing material 4506 board 4507 Filling material 4509 Thin-film transistor 4510 Thin-film transistor 4511 Light-emitting element 4512 Electroluminescent layer 4513 Electrode layer 4515 Connection terminal electrode 4516 Terminal electrode 4517 Electrode layer 4518a FPC 4519 Anisotropic conductive film 4520 Bulkhead 5300 board 5301 Pixel unit 5302 Scanning line driver circuit 5303 Signal line driver circuit 5400 board 5401 Pixel unit 5402 Scanning line driver circuit 5403 Signal line driver circuit 5404 Scanning line driver circuit 6400 pixels 6401 Switching transistor 6402 Drive transistor 6403 Capacitor element 6404 Light-emitting element 6405 signal line 6406 scan lines 6407 Power line 6408 Common electrode 7001 TFT 7002 Light-emitting element 7003 Cathode 7004 Light-emitting layer 7005 Anode 7011 Driving TFT 7012 Light-emitting element 7013 Cathode 7014 Light-emitting layer 7015 Anode 7016 Shielding membrane 7017 Conductive film 7021 Driving TFT 7022 Light-emitting element 7023 Cathode 7024 Light-emitting layer 7025 Anode 7027 Conductive film 9100 Mobile Phone 9101 Housing 9102 Housing 9103 Connection section 9104 Display section 9106 Operation key 9200 Portable information terminal equipment 9201 Case 9202 Display section 9203 Housing 9205 keyboard 9207 Connection section 9400 Communication Equipment 9401 Housing 9402 Operation button 9403 External input terminal 9404 Microphone 9405 Speaker 9406 Light-emitting part 9410 Display device 9411 Housing 9412 Display section 9413 Operation button 9500 Digital Video Camera 9501 Housing 9503 Display section 9600 Television Equipment 9601 Housing 9603 Display section 9605 Stand 9607 Display section 9609 Operation Key 9610 Remote Controlled Machine 9700 Digital Photo Frame 9701 Housing 9703 Display section 9800 Computer 9801 Case 9802 Display section 9803 keyboard 9804 Case

Claims

[Claim 1] an oxide semiconductor layer over a substrate having an insulating surface; a gate wiring having a region overlapping with the oxide semiconductor layer and including a stack of a first conductive layer and a second conductive layer on the first conductive layer; a source wiring electrically connected to the oxide semiconductor layer and including a third conductive layer and a fourth conductive layer stacked on the third conductive layer; a part of the gate wiring functions as a gate electrode, and the gate electrode is formed of the first conductive layer; a part of the source wiring functions as a source electrode, and the source electrode is formed of the third conductive layer; each of the first conductive layer and the third conductive layer has a light-transmitting property and includes indium tin oxide, indium tin oxide containing silicon oxide, organic indium, organic tin, zinc oxide, titanium nitride, indium zinc oxide containing zinc oxide, zinc oxide doped with gallium, tin oxide, indium oxide containing tungsten oxide, indium zinc oxide containing tungsten oxide, indium oxide containing titanium oxide, or indium tin oxide containing titanium oxide; each of the second conductive layer and the fourth conductive layer comprises aluminum, molybdenum, titanium, tungsten, neodymium, copper, or silver; In the extending portion of the gate wiring, the first conductive layer has a portion that does not overlap with the second conductive layer, In the extending portion of the source wiring, the third conductive layer has a portion that does not overlap with the fourth conductive layer.

Images