Semiconductor and display devices

Abstract

To satisfy the need for a protection circuit which has an appropriate composition and a smaller occupied area in order to utilize characteristics of a display device using an oxide semiconductor which is excellent in operating characteristics and which can be manufactured at a low temperature.SOLUTION: A semiconductor device comprises a protection circuit which is composed of a nonlinear element 170a including a gate insulation layer 102 which covers a gate electrode 111, a first oxide semiconductor layer 113 which overlaps the gate electrode 111 on the gate insulation layer 102, and a first wiring layer 117a and a second wiring layer 117b which have ends overlapping the gate electrode on the first oxide semiconductor layer 113 and in each of which a conductive layer and a second oxide semiconductor layer are laminated. By connecting the gate electrode of the nonlinear element with a scan line or a signal line, and by directly connecting the first wiring layer or the second wiring layer of the nonlinear element for applying potential of the gate electrode with the connection of the gate electrode layer, a stable operation due to reduction in connection resistance and a reduced occupied area of a connection part are achieved.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] This invention relates to a display device using an oxide semiconductor. [Background technology]

[0002] Thin-film transistors, such as those formed on a flat plate like a glass substrate, are exemplified by liquid crystal displays. They are made from amorphous silicon and polycrystalline silicon. Thin-film transistors using glass have low field-effect mobility, but are suitable for large-area applications of glass substrates. It can respond to this, while thin-film transistors using polycrystalline silicon have a field-effect mobility of Although expensive, it requires crystallization processes such as laser annealing, and is essential for large-area glass substrates. It has the characteristic of not being adaptable to sushi.

[0003] In contrast, thin-film transistors are fabricated using oxide semiconductors, and these transistors are used in electronic devices and optical devices. The technology is attracting attention for its application in various applications. For example, zinc oxide (ZnO) as an oxide semiconductor film. Alternatively, thin-film transistors can be made using oxide semiconductors containing indium, gallium, and zinc. The technology for manufacturing and using it in switching elements of image display devices is described in Patent Documents 1 and 2. It has been disclosed. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2007-123861 [Patent Document 2] Japanese Patent Publication No. 2007-96055 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Thin-film transistors using oxide semiconductors as channel formation regions utilize amorphous silicon. It operates faster than thin-film transistors, and uses polycrystalline silicon. It has the characteristic of being easier to manufacture than other materials. In other words, it uses oxide semiconductors. By doing so, even at low temperatures ranging from room temperature to below 300°C, the field effect transfer can be controlled. It is possible to fabricate thin-film transistors with high precision.

[0006] Leveraging the characteristics of oxide semiconductors, which have excellent operating characteristics and can be manufactured at low temperatures, this device offers high reliability. To guarantee this, a protective circuit with an appropriate configuration is required. Furthermore, miniaturization of the display device is also necessary. In order to achieve this, it becomes necessary to reduce the area occupied by the protection circuit.

[0007] One aspect of the present invention aims to provide a structure suitable as a protective circuit.

[0008] One aspect of the present invention relates to various applications where an oxide semiconductor is fabricated by laminating an insulating film and a conductive film. In the display device, the function of the protection circuit is enhanced to stabilize operation and reduce the footprint of the protection circuit. One of its objectives is to promote this goal. [Means for solving the problem]

[0009] One aspect of the present invention is a protection circuit formed by a nonlinear element made of an oxide semiconductor. This is a display device. This nonlinear element is constructed by combining oxide semiconductors with different oxygen content. This is achieved. Furthermore, at least one of the first and second wiring layers of this nonlinear element This is directly connected to the gate electrode or a conductive film formed in the same process as the gate electrode. .

[0010] In an exemplary aspect of the present invention, scanning lines and signal lines are provided intersecting each other on a substrate having an insulating surface , a pixel portion in which pixel electrodes are arranged in a matrix, and an oxide semiconductor is provided in a region outside the pixel portion The display device includes a non-linear element formed as described above. In the pixel portion, a channel is formed in the first oxide semiconductor layer It includes a thin film transistor in which a channel formation region is formed. The thin film transistor in the pixel portion includes a scanning a gate electrode connected to the line, a first wiring layer connected to the signal line and in contact with the first oxide semiconductor layer, and a second wiring layer connected to the pixel electrode and in contact with the first oxide semiconductor layer. The non-linear element is arranged between the signal input terminal provided along the peripheral portion of the substrate and the pixel portion A non-linear element is provided between the signal input terminal and the pixel portion. The non-linear element includes a gate a gate electrode and a gate insulating layer covering the gate electrode, and the gate insulating layer is provided on the gate insulating layer a first oxide semiconductor layer overlapping with the gate electrode, and the gate is provided on the first oxide semiconductor layer an end portion overlaps the gate electrode, and the first wiring layer and the second wiring layer are formed by laminating a conductive layer and a second oxide semiconductor layer It includes a wiring layer. Further, the gate electrode of the non-linear element is connected to the scanning line or the signal line, and the first wiring layer or the second wiring layer of the non-linear element is connected to the gate electrode such that the potential of the gate electrode is applied and is directly connected to the layer.

[0011] In an exemplary aspect of the present invention, scanning lines and signal lines are provided intersecting each other on a substrate having an insulating surface , a pixel portion in which pixel electrodes are arranged in a matrix, and a protection circuit is provided in a region outside the pixel portion The display device according to claim 1. In the pixel portion, a thin film in which a channel formation region is formed in the first oxide semiconductor layer It includes a transistor. The thin film transistor in the pixel portion has a gate electrode connected to the scanning line , a first wiring layer connected to the signal line and in contact with the first oxide semiconductor layer, and a first oxide connected to the pixel electrode and a second wiring layer in contact with the oxide semiconductor layer. In a region outside the pixel portion, the scanning line and a common A protective circuit is provided for connecting the wiring, and another protective circuit is provided for connecting the signal line and the common wiring. The protective circuit comprises a gate electrode and a gate insulating layer covering the gate electrode, and the gate insulating layer A first oxide semiconductor layer superimposed on the gate electrode, and on the first oxide semiconductor layer In this configuration, the gate electrode and the end are superimposed, and the conductive layer and the second oxide semiconductor layer are stacked. It has a nonlinear element having a wiring layer and a second wiring layer. The gate electrode of the linear element is directly connected to the first or second wiring layer.

[0012] The ordinal numbers "1st" and "2nd" are used for convenience only and do not represent the order of processes or stacking. This does not indicate that the invention is uniquely named. This does not indicate anything. [Effects of the Invention]

[0013] According to one aspect of the present invention, a protection circuit is configured using a nonlinear element made of an oxide semiconductor. A display device with a structure more suitable as a protection circuit can be obtained. In a connection structure between a monooxide semiconductor layer and a wiring layer, the electrical conductivity is higher than that of the monooxide semiconductor layer. By providing a region that bonds with a high-performance second oxide semiconductor layer, stable operation can be achieved. This enhances the functionality of the protection circuit and stabilizes its operation.

[0014] Furthermore, a contact hole reaching the first or second wiring layer, and the gate or gate A contact hole is provided that reaches the wiring formed in the same layer as the electrode, and the first wiring is made in a different wiring layer. A method for connecting a layer or a second wiring layer to a gate electrode or wiring formed on the same layer as the gate electrode. However, using this method, one connection results in two interfaces and two contact holes. It is formed.

[0015] A nonlinear element constituting a protective circuit according to one aspect of the present invention is a conductive layer of the first wiring layer or the second wiring layer. Because it connects directly to the gate electrode or wiring formed on the same layer as the gate electrode, one contact Only one interface and one contact hole are formed during the connection. Because there is only one interface, contact resistance is suppressed compared to methods that connect via another wiring layer. This is possible. As a result, the protection circuit using nonlinear elements operates stably. Also, the connection is necessary Because there is only one contact hole, the connection is easier compared to connecting via another wiring layer. This reduces the area occupied by each part, and as a result, reduces the area occupied by the protection circuit. This allows for miniaturization of display devices. [Brief explanation of the drawing]

[0016] [Figure 1] A diagram illustrating the positional relationship between the signal input terminals, scan lines, signal lines, protection circuits including nonlinear elements, and pixel sections that constitute a display device. [Figure 2] A diagram showing an example of a protection circuit. [Figure 3] A diagram showing an example of a protection circuit. [Figure 4] A plan view showing an example of a protection circuit. [Figure 5] A cross-sectional view showing an example of a protection circuit. [Figure 6] A cross-sectional diagram illustrating the manufacturing process of a protective circuit. [Figure 7] A cross-sectional diagram illustrating the manufacturing process of a protective circuit. [Figure 8] A plan view showing an example of a protection circuit. [Figure 9] A plan view showing an example of a protection circuit. [Figure 10] Cross-section of an electronic paper display. [Figure 11] A diagram illustrating the block diagram of a semiconductor device. [Figure 12] A diagram illustrating the configuration of a signal line drive circuit. [Figure 13] A timing chart illustrating the operation of a signal line drive circuit. [Figure 14] A timing chart illustrating the operation of a signal line drive circuit. [Figure 15] A diagram illustrating the configuration of a shift register. [Figure 16] Figure 14 illustrates the connection configuration of the flip-flops shown. [Figure 17] A top view and a cross-sectional view illustrating the semiconductor device of the embodiment. [Figure 18] A cross-sectional view illustrating the semiconductor device of the embodiment. [Figure 19] A diagram illustrating the pixel equivalent circuit of the semiconductor device according to the embodiment. [Figure 20] A diagram illustrating a semiconductor device according to an embodiment. [Figure 21] A top view and a cross-sectional view illustrating the semiconductor device of the embodiment. [Figure 22] A diagram illustrating examples of how electronic paper can be used. [Figure 23] An external view showing an example of an e-book. [Figure 24] External view showing examples of television equipment and digital photo frames. [Figure 25] An external view showing an example of a gaming machine. [Figure 26] An external view showing an example of a mobile phone. [Modes for carrying out the invention]

[0017] Embodiments of the present invention will be described below with reference to the drawings. However, the present invention will not be described below. The present invention is not limited to, and its form and details may vary without departing from the spirit and scope of the present invention. Those skilled in the art will readily understand that it can be modified in various ways. Therefore, the present invention is as follows: The present invention is not limited to the descriptions of the embodiments. In this context, symbols that refer to the same thing are used consistently across different drawings.

[0018] (Embodiment 1) In this embodiment, a display device is provided in which a protection circuit including a nonlinear element is formed around the pixel portion and its surroundings. One embodiment will be described with reference to the drawings.

[0019] Figure 1 shows a protection circuit that constitutes a display device, including signal input terminals, scan lines, signal lines, and nonlinear elements. This is a diagram illustrating the positional relationship of the pixel portion. Scan lines 13 and The signal lines 14 intersect to form the pixel section 17.

[0020] The pixel section 17 is composed of multiple pixels 18 arranged in a matrix. The pixels 18 are scanned The pixel transistor 19, retaining capacitance unit 20, and pixel electrode 21 are connected to line 13 and signal line 14. It is composed of including these elements.

[0021] In the pixel configuration illustrated here, the holding capacitance unit 20 has one electrode connected to the pixel transistor 19 This shows the case where one electrode is connected to the other electrode, and the other electrode is connected to the capacitance line 22. Also, the pixel electrode 21 is While driving the display elements (liquid crystal elements, light-emitting elements, contrast media (electronic ink), etc.) These form the electrodes. The other electrode of these display elements is connected to the common terminal 23.

[0022] The protection circuit is disposed between the pixel unit 17 and the scan line input terminal 11 and the signal line input terminal 12. In this embodiment, multiple protection circuits are provided for the scan line 13, signal line 14 and capacitance. A surge voltage is applied to the bus line 27 due to static electricity, etc., causing damage to the pixel transistor 19, etc. It is designed to prevent this from happening. Therefore, when a surge voltage is applied to the protection circuit, The common wiring 29 or common wiring 28 is configured to allow electric charge to escape.

[0023] In this embodiment, protection circuits 24, 25, and 26 are arranged within the display device. An example is shown. However, the configuration of the protection circuit is not limited to this.

[0024] Figure 2 shows an example of a protection circuit. This protection circuit is connected in parallel between scan line 13 and common wiring 29. It is composed of arranged nonlinear elements 30 and nonlinear elements 31. The nonlinear element 31 is a two-terminal element such as a diode or a three-terminal element such as a transistor. It is composed of elements. For example, it can be formed using the same process as the pixel transistors in the pixel section. Therefore, by connecting the gate terminal and drain terminal, for example, it exhibits characteristics similar to a diode. It can be given to hold.

[0025] The first terminal (gate) and third terminal (drain) of the nonlinear element 30 are connected to the scan line 13. The second terminal (source) is connected to the common wiring 29. Also, the first terminal of the nonlinear element 31 is connected to the common wiring 29. The gate and the third terminal (drain) are connected to the common wiring 29, and the second terminal (source) is connected to the running It is connected to line 13. In other words, the protection circuit shown in Figure 2 is connected to the two transistors. Each of them connects the scan line 13 and the common wiring 29 with the rectification direction facing in opposite directions. Yes, there is. In other words, between scan line 13 and common wiring 29, the rectification direction is from scan line 13 to common wiring 29. The transistor heading towards wiring 29 and the transistor whose rectification direction is from common wiring 29 towards scan line 13 This configuration involves connecting the ZISTA.

[0026] The protection circuit shown in Figure 2 is configured such that when the scan line 13 is positively or negatively charged with static electricity, etc., the common wiring 29 When an electric charge is applied, a current flows in the direction that cancels out that charge. For example, if scan line 13 is positively charged If this occurs, current flows in the direction that releases the positive charge into the common wiring 29. This action causes the band Electrostatic discharge or threshold voltage failure of the pixel transistor 19 connected to the charged scan line 13 This prevents the scan line 13 from intersecting with the charged scan line 13 via the insulating layer. This prevents dielectric breakdown of the insulating film between the wiring and other wiring.

[0027] Figure 2 shows a nonlinear element 30 with the first terminal (gate) connected to the scan line 13, and a common wiring 2 A nonlinear element 31 with the first terminal (gate) connected to 9, that is, two elements with opposite rectification directions. Using a set of nonlinear elements, a common distribution is made between the second terminal (source) and the third terminal (drain) of each element. Line 29 and scan line 13 are connected in parallel. That is, nonlinear element 30 and nonlinear element 31 They are parallel.

[0028] Another configuration involves adding nonlinear elements connected in parallel to improve the operational stability of the protection circuit. It may be increased. For example, Figure 3 shows a nonlinear circuit provided between scan line 13 and common wiring 29. It is composed of element 30a and nonlinear element 30b and nonlinear element 31a and nonlinear element 31b The protection circuit is shown. This protection circuit has two terminals (gates) connected to the common wiring 29. The nonlinear elements (30b, 31b) and two terminals (gates) connected to scan line 13. A total of four nonlinear elements (30a, 31a) are used. That is, in the rectification direction A pair of two nonlinear elements connected so that their directions are opposite to each other is connected to the common wiring 29 and scan line 1 There are two sets connected between 3. In other words, between scan line 13 and common wiring 29, the rectification direction Two transistors are connected from scan line 13 to common wiring 29, and the rectification direction is common wiring 29 This configuration connects two transistors from to scan line 13. By connecting line 29 and scan line 13 with four nonlinear elements, a surge voltage is imprinted on scan line 13. Not only when electricity is added, but also when the common wiring 29 becomes charged due to static electricity, etc. This prevents the charge from flowing directly into scan line 13. Note that Figure 9 shows... Figure 9(B) shows one configuration in which four nonlinear elements are arranged on a substrate, along with an equivalent circuit diagram. The equivalent circuit diagram shown in Figure 3 is equivalent to the equivalent nonlinear circuit diagram shown in Figure 9(B). The element corresponds to the nonlinear element shown in Figure 3. Specifically, the nonlinear element 740a is a nonlinear element. The nonlinear element 740b corresponds to the nonlinear element 31b, and the nonlinear element 7 40c corresponds to nonlinear element 30a, and nonlinear element 740d corresponds to nonlinear element 31a. Furthermore, scan line 651 in Figure 9 corresponds to scan line 13, and common wiring 650 corresponds to common wiring 29. Corresponds. Therefore, the four nonlinear elements exemplified in Figure 9(A) are arranged on a substrate to form a retaining wall. One embodiment of the protection circuit is the embodiment of the protection circuit illustrated in Figure 3.

[0029] Furthermore, as an example of a protection circuit using an odd number of nonlinear elements, an example of the arrangement of nonlinear elements on a substrate is shown. Figure 8(A) shows the equivalent circuit diagram, and Figure 8(B) shows the equivalent circuit diagram. In this circuit, for the nonlinear element 730c Nonlinear elements 730b and 730a are connected as switching elements. By connecting nonlinear elements in series as shown, the instantaneous reaction applied to the nonlinear elements constituting the protection circuit It can distribute the load across different systems.

[0030] Figure 2 shows an example of a protection circuit installed on the scan line 13 side, but a similar protection circuit can be installed on the signal line 14 It can also be applied to the other side.

[0031] Figure 4(A) is a plan view showing an example of a protection circuit, and (B) shows its equivalent circuit diagram. Figure 5 shows a cross-sectional view corresponding to the Q1-Q2 cutting line shown in Figure 4(A). The following explanation is provided below. Now, let's explain an example of a protection circuit configuration with reference to Figures 4 and 5.

[0032] The nonlinear elements 170a and 170b are gates formed in the same layer as the scan line 13. It has an electrode 111 and a gate electrode 16. On the gate electrode 111 and gate electrode 16 A gate insulating film 102 is formed thereon. A first oxide semiconductor layer is formed on the gate insulating film 102. 113 is formed and faces the gate terminal 111 via the first oxide semiconductor layer 113. A first wiring layer 117a and a second wiring layer 117b are provided. 70a and the nonlinear element 170b have the same configuration in their main parts.

[0033] In one aspect of the present invention, through a contact hole 128 provided in the gate insulating film 102, The scan line 13 is formed in the same layer as electrode 111, and the third terminal (Dream) of the nonlinear element 170a. By directly connecting the input, not only can the formation of an interface associated with the connection be suppressed, This can suppress the formation of contact holes associated with the connection to just one.

[0034] The first oxide semiconductor layer 113 is located beneath the opposing first wiring layer 117a and second wiring layer 117b. It is provided so as to cover the gate electrode 111 via a gate insulating film. That is, The oxide semiconductor layer 113 is superimposed on the gate electrode 111 and on the upper surface of the gate insulating film 102 It is provided so as to be in contact with the lower surfaces of the second oxide semiconductor layers 114a and 114b. Here, the first wiring layer 117a is connected to the second oxide semiconductor layer 11 from the first oxide semiconductor layer 113 side. It has a structure in which 4a and conductive layer 115a are laminated. Similarly, the second wiring layer 117b The oxide semiconductor layer 114b and the conductive layer 115b are stacked from the oxide semiconductor layer 113 side. It has the following configuration.

[0035] The second oxide semiconductor layer (114a and 114b) is composed of the first oxide semiconductor layer 113 and the conductive layer (1 It is in contact with and provided between 15a and 115b), and the first oxide semiconductor layer 113 and the first oxide The second oxide semiconductor layer (114a and 114b) has higher electrical conductivity than the monocrystalline semiconductor layer 113. A junction is formed between oxide semiconductor layers with different physical properties, where they come into contact. By providing this to the nonlinear element 170a and the nonlinear element 170b, stable operation is achieved. This becomes possible. In other words, thermal stability increases, and stable operation becomes possible. This enhances the function of the protection circuit and stabilizes its operation. Furthermore, it reduces junction leakage. This reduces the characteristics of the nonlinear element 170a and the nonlinear element 170b.

[0036] In this specification, the oxide semiconductor used for the first oxide semiconductor layer is InMO3(ZnO) m (m A thin film is formed as indicated by >0), and this thin film is used as a semiconductor layer in a nonlinear element and a thin film. A film transistor will be fabricated. Note that M is selected from Ga, Fe, Ni, Mn, and Co. It indicates one or more metallic elements. For example, M may be Ga, It may also contain other metal elements besides Ga, such as Ga and Ni or Ga and Fe. In the above oxide semiconductor, in addition to the metal element M, Fe is included as an impurity element. Some products contain Ni or other transition metal elements, or oxides of such transition metals. In this book, this thin film is also called an In-Ga-Zn-O non-single-crystal film.

[0037] Inductively coupled plasma mass spectrometry (ICP-MS) Representative measurement examples are shown using (ed Plasma Mass Spectrometry). As shown in 1, indium oxide (In2O3), gallium oxide (Ga2O3), and zinc oxide (Z A target with a composition ratio of nO) of 1:1:1 (=In2O3:Ga2O3:ZnO) Using In:Ga:Zn=1:1:0.5, the argon gas flow rate in the sputtering method was set to 40s. The oxide semiconductor film obtained under condition 1 with ccm is InGa 0.95 Zn 0.41 O 3. 33 Furthermore, the argon gas flow rate in the sputtering method was 10 sccm, and the oxygen flow rate was 5 sccm. The oxide semiconductor film obtained under condition 2 is InGa 0.94 Zn 0.40 O 3.31 in be.

[0038] [Table 1]

[0039] Furthermore, the measurement method is Rutherford backscattering analysis (RBS). The results quantified using (scalculating spectrometry) are shown in the table. As shown in 2.

[0040]

Table 2

[0041] As a result of measurement of the sample under Condition 1 by RBS analysis, the oxide semiconductor film is InGa 0.93 Zn0 .44 O 3.49 . Further, as a result of measurement of the sample under Condition 2 by RBS analysis, the oxide semiconduc tor film is InGa 0.92 Zn 0.45 O 3.86 .

[0042] In the crystal structure of the In-Ga-Zn-O-based non-single-crystal film, an amorphous structure is observed in X-ray diffraction (XRD : X-ray diffraction) analysis. After film formation by sputtering, heat treatment is performed at 200°C to 500°C, typically 300°C to 400°C, for 10 minutes to 100 minutes . In addition, for the electrical characteristics of a thin film transistor at a gate voltage of ±20 V, a transistor with an on-off ratio of 10 or more and a mobility of 10 cm 9 / V·S or more can be manufactured. 2

[0043] The second oxide semiconductor layers (114a and 114b) have higher electrical conductivity than the first oxide semiconductor layer 113 . Therefore, in the non-linear element 170a and non-linear element 170b of the present embodiment, the second oxide semiconductor layers (114a and 114b) exhibit the same function as the source region and drain region of a transistor. The second oxide semiconductor layers (114a and 114b) that serve as the source region and drain region have n-type conductivity, and the activation energy (ΔE) is 0.01 eV or more and 0.1 eV or less, and can also be called an n region. In addition + ​​​The second oxide semiconductor layer is a non-single-crystal oxide semiconductor layer containing In, Ga, Zn, and O. In some cases, nanocrystals may be present within the non-single-crystal structure.

[0044] An interlayer insulating film 107 is provided on the first oxide semiconductor layer 113. It is formed from oxides such as silicon oxide or aluminum oxide. Or silicon nitride, aluminum nitride, silicon oxide nitride or oxide on aluminum oxide By layering aluminum nitride, the protective film's functionality can be further enhanced.

[0045] In any case, the interlayer insulating film 107 in contact with the first oxide semiconductor layer 113 is made of oxide. As a result, oxygen is extracted from the first oxide semiconductor layer 113, causing it to degrade into an oxygen-deficient type. This can prevent the above. Also, the first oxide semiconductor layer 113 is directly connected to the nitride insulating layer. By creating a configuration that does not come into contact with the first oxide semiconductor layer 113, hydrogen in the nitride diffuses into the first oxide semiconductor layer 113. This can prevent the formation of defects caused by acid groups and other factors.

[0046] Thus, according to this embodiment, a table having a protection circuit made of an oxide semiconductor A device can be obtained. A second oxide semiconductor layer has higher electrical conductivity than the first oxide semiconductor layer. By providing a region where the conductive layer and the first oxide semiconductor layer are joined via a body layer, stable operation is achieved. This makes it possible to enhance the function of the protection circuit and stabilize its operation. It can. Also, through the contact hole 128 provided in the gate insulating film 102, the gate electrode The scan line 13 formed in the same layer as 111, and the third terminal (drain) of the nonlinear element 170a By directly connecting them, not only can the formation of an interface associated with the connection be suppressed, but the connection This allows for the formation of a single contact hole, thereby improving the function of the protection circuit. In addition to improving operational stability, it also reduces the footprint of the protection circuit, and the display device This allows for miniaturization. In particular, the number of nonlinear elements constituting the protection circuit can be increased to three or four. The more this is done, the greater the effect of suppressing the number of interfaces and contact holes.

[0047] Figures 4 and 5 show an example of a protection circuit provided on scan line 13, but similar protection circuits... The road can be applied to signal lines, capacity bus lines, and so on.

[0048] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments. That is the case.

[0049] (Embodiment 2) In this embodiment, the process for manufacturing the protection circuit shown in Figure 4(A) in Embodiment 1 is the same as the process for manufacturing the protection circuit in Embodiment 1. The state will be explained with reference to Figures 6 and 7. Figures 6 and 7 show the Q1-Q2 cutting line in Figure 4(A). This shows a corresponding cross-sectional view.

[0050] In Figure 6(A), the translucent substrate 100 is made of commercially available barium borosilicate Using glass substrates such as glass, aluminoborosilicate glass, and aluminosilicate glass. It is possible. For example, in terms of component ratio, barium oxide (Ba) is better than boric acid (B2O3). It is preferable to use a glass substrate that contains a large amount of O) and has a strain point of 730°C or higher. This is because the glass substrate does not become distorted even when the layer is heat-treated at a high temperature of around 700°C. .

[0051] Next, gate wiring including gate electrode 111 and scan line 13, capacitive wiring and terminal ends A conductive film is deposited on the entire surface of the substrate 100. The conductive film is made of aluminum (Al) or copper (C). It is preferable to form it with a low-resistance conductive material such as u), but Al alone has poor heat resistance, Furthermore, because it has problems such as being prone to corrosion, it is formed in combination with a heat-resistant conductive material. Examples of conductive materials include titanium (Ti), tantalum (Ta), tungsten (W), and molybdenum. Selected from butene (Mo), chromium (Cr), Nd (neodymium), and Sc (scandium). The element, or an alloy containing the above-mentioned elements, or an alloy film combining the above-mentioned elements, Alternatively, it may be formed from a nitride containing the aforementioned elements.

[0052] The conductive film that forms the wiring layer including the gate electrode 111 is formed with a thickness of 50 nm to 300 nm. By making the thickness of the conductive film that forms the wiring layer including the gate electrode 111 300 nm or less, It is possible to prevent step breaks in the semiconductor film and wiring that are formed later. Also, the gate electrode 111 is included. By making the thickness of the conductive film that forms the wiring layer 150 nm or more, the resistance of the gate electrode is reduced. It is possible to do so, and it can be scaled up to cover a large area.

[0053] In this case, a conductive film mainly composed of aluminum and a titanium film are applied to the entire surface of the substrate 100. The film is formed by layering these materials using a sputtering method.

[0054] Next, the resist mask formed using the first photomask in this embodiment is used The unnecessary parts of the conductive film formed on the substrate are etched and removed to create wiring and electrodes ( Gate wiring, capacitive wiring, and terminals including electrode 111 are formed. At this time, at least The gate electrode 111 is also etched so that a tapered shape is formed at its end. A cross-sectional view is shown in Figure 6(A).

[0055] Next, the gate insulating film 102 is formed. As an insulating film that can be used as the gate insulating film 102... This includes silicon oxide film, silicon nitride film, silicon oxide nitride film, silicon oxide nitride film, aluminum oxide film, Magnesium oxide film, aluminum nitride film, yttrium oxide film, hafnium oxide film, acid Tantalum oxide films can be cited as an example.

[0056] Here, a silicon oxide nitride film is defined as a film whose composition has a higher oxygen content than nitrogen. The concentration ranges are 55-65 atomic percent for oxygen, 1-20 atomic percent for nitrogen, and 25- This refers to materials containing 35 atomic percent of hydrogen, with hydrogen in the range of 0.1 to 10 atomic percent. It also refers to silicon nitride oxide. A film is a material whose composition contains more nitrogen than oxygen, and whose concentration range is It contains 15-30 atomic percent oxygen, 20-35 atomic percent nitrogen, 25-35 atomic percent silicon, and hydrogen. This refers to substances that are present in an amount ranging from 15 to 25 atomic percent.

[0057] The gate insulating film may be a single layer, or it may be formed by stacking two or three insulating films. For example If so, the gate insulating film in contact with the substrate is formed using a silicon nitride film or a silicon oxide nitride film. As a result, the adhesion between the substrate and the gate insulating film is increased, and when a glass substrate is used as the substrate, It is possible to prevent impurities from diffusing into the oxide semiconductor layer, and furthermore, gate This prevents oxidation of the wiring layer including electrode 111. In other words, it prevents film peeling. This can improve the electrical characteristics of the thin-film transistors that are formed later.

[0058] Furthermore, the thickness of the gate insulating film 102 is set to 50-250 nm. A value of 1 nm or greater is preferable because it can cover the irregularities of the wiring layer including the gate electrode 111. Here, the gate insulating film 102 is made by plasma CVD or sputtering. A silicon oxide film with a thickness of 0 nm is deposited.

[0059] Next, the resist mask formed using the second photomask in this embodiment is used The gate insulating film 102 is etched to create a contact hole 128 that reaches the scan line 13. To form.

[0060] Next, the gate insulating film 102 is subjected to plasma treatment before the formation of the first oxide semiconductor film. Here, inverse sputtering is performed by introducing oxygen gas and argon gas to generate plasma, and exposure The gate insulating layer is irradiated with oxygen radicals or oxygen. In this way, the surface is coated with Remove the debris.

[0061] Furthermore, the plasma treatment of the gate insulating film 102, the first oxide semiconductor film, and the second oxide semiconductor The membrane is formed by sputtering, and the gas introduced into the chamber or the target placed there is switched as needed. This allows for continuous film deposition without exposure to the atmosphere. Continuous film deposition prevents the inclusion of impurities. In such cases, it is preferable to use a multi-chamber type manufacturing apparatus.

[0062] In particular, the plasma treatment of the gate insulating film 102 in contact with the first oxide semiconductor film and the first oxide semiconductor It is desirable to perform the deposition of body membranes continuously without exposure to the atmosphere. By performing continuous deposition, A layered interface free from contamination by atmospheric components such as water vapor, and by impurities and dust suspended in the atmosphere. Because it can be formed in this way, variations in the characteristics of nonlinear elements and thin-film transistors can be reduced.

[0063] In this specification, continuous film deposition refers to the process from the first processing step performed by sputtering to the sputtering process. During the series of processes up to the second processing step, the atmosphere in which the substrate to be processed is placed is such as air. Always in a vacuum or inert gas atmosphere (nitrogen atmosphere or dilute gas atmosphere) without exposure to contaminated atmospheres. This refers to the control of the atmosphere (gas atmosphere). By performing continuous film deposition, the cleaned surface It is possible to perform film deposition while keeping moisture and other substances from adhering to the processing substrate. Plasma processing, such as tuttering, is also included in continuous film deposition.

[0064] Next, without exposing the plasma-treated gate insulating film 102 to the atmosphere, the first oxide semiconductor A film is formed. The plasma-treated gate insulating film 102 is subjected to a first oxide without being exposed to the atmosphere. By forming a semiconductor film, dust is deposited at the interface between the gate insulating film 102 and the first oxide semiconductor film. This prevents problems such as moisture adhesion. Furthermore, the deposition of the first oxide semiconductor film is performed first. The same chamber used for reverse sputtering may be used, or it may be done without exposure to the atmosphere. If film deposition is possible, deposit the film in a different chamber than the one where reverse sputtering was performed earlier. That's fine.

[0065] Here, we have an 8-inch diameter oxide semiconductor target containing In, Ga, and Zn (composition ratio). As such, using In2O3:Ga2O3:ZnO=1:1:1, the substrate and target Distance between them: 170 mm, pressure: 0.4 Pa, DC power supply: 0.5 kW, argon or The film is deposited under an oxygen atmosphere. Furthermore, using a pulsed DC power supply can reduce dust. This is preferable because it results in a uniform film thickness distribution. The film thickness of the first oxide semiconductor film is 5 nm to 200 nm. Let m be the thickness of the first oxide semiconductor film. In this embodiment, the thickness of the first oxide semiconductor film is 100 nm.

[0066] The first oxide semiconductor film is formed by using different deposition conditions than those for the second oxide semiconductor film. It has a different composition from semiconductor films. For example, it has a higher oxygen concentration than that in a dioxide semiconductor film. A certain amount of oxygen is incorporated into the first oxide semiconductor film. For example, the deposition conditions for the second oxide semiconductor film are The ratio of oxygen gas flow rate to argon gas flow rate is more important than the film deposition conditions for the first oxide semiconductor film. The condition is that the proportion of oxygen gas flow rate is large. Specifically, the deposition of a second oxide semiconductor film. The conditions are: under a noble gas atmosphere (argon or helium, etc.) (or oxygen gas at 10% or less), The argon gas concentration should be 90% or higher, and the deposition conditions for the first oxide semiconductor film should be under an oxygen atmosphere (or Assume the oxygen gas flow rate is equal to or greater than the argon gas flow rate.

[0067] By incorporating a large amount of oxygen into the first oxide semiconductor film, it becomes possible to create a film that is more oxygen-rich than the second oxide semiconductor film. The conductivity can be lowered. Also, a large amount of oxygen can be incorporated into the first oxide semiconductor film. This allows for a reduction in off-current, making it possible to use thin-film transistors with a high on / off ratio. You can obtain the item.

[0068] Next, a second oxide semiconductor film is deposited on the first oxide semiconductor film by sputtering. Here, An 8-inch diameter oxide semiconductor target containing In, Ga, and Zn (In2O3:Ga Using 2O3:ZnO=1:1:1, the distance between the substrate and the target was 170mm. Pressure 0.4 Pa, DC power supply 0.5 kW, film deposition temperature at room temperature, argon gas flow rate A 40 sccm sputtering process is performed. This results in a second oxide semiconductor film. A semiconductor film composed of In, Ga, Zn, and oxygen is formed. (In2O3:Ga2O3) Despite intentionally using a target with ZnO=1:1:1, immediately after film deposition... Oxide semiconductor films containing crystal grains with a size of 1 nm to 10 nm are often formed. - Component ratio of the film, deposition pressure (0.1 Pa ~ 2.0 Pa), power (250 W ~ 3000 W) Adjust the following as appropriate: (8-inch diameter), temperature (room temperature to 100°C), and reactive sputtering film deposition conditions. This allows you to determine the presence or absence of crystal grains, their density, and their diameter size within a range of 1 nm to 10 nm. It can be said that it can be restricted. The thickness of the oxide semiconductor film is set to 5 nm to 20 nm. Of course, the film If crystal grains are present, the size of the included crystal grains must not exceed the thickness of the film. In this embodiment, the thickness of the second oxide semiconductor film is set to 5 nm.

[0069] Next, a third photolithography process is performed to form a resist mask, and the first oxide semiconductor is formed. The conductive film and the second oxide semiconductor film are etched. Here, ITO07N (Kanto Chemical Co., Ltd.) is used. By wet etching using (manufactured), unwanted parts are removed to form the first oxide semiconductor layer 11 3 and the second oxide semiconductor layer 114 are formed. Note that etching here is wet etching. Etching is not the only method; dry etching may also be used. A cross-sectional view at this stage is shown in Figure 6. This is shown in B).

[0070] Next, a conductive film made of a metallic material is placed on the second oxide semiconductor layer 114 and the gate insulating film 102. 105 is formed by sputtering or vacuum deposition. The material for the conductive film 105 is Al, Cr , elements selected from Ta, Ti, Mo, W, or alloys containing the above elements, Examples include alloy films combining the elements described above.

[0071] Furthermore, when heat treatment is performed at 200°C to 600°C, the conductive film must have sufficient heat resistance to withstand this heat treatment. It is preferable to have it in place. Al alone has problems such as poor heat resistance and susceptibility to corrosion. Therefore, it is formed in combination with a heat-resistant conductive material. Heat-resistant conductive material to be combined with Al The materials used are titanium (Ti), tantalum (Ta), tungsten (W), and molybdenum (M). o), an element selected from chromium (Cr), Nd (neodymium), Sc (scandium), or an alloy composed of the above-mentioned elements, or an alloy film made up of the above-mentioned elements, or the above-mentioned It is formed from a nitride composed of the specified elements.

[0072] Here, the conductive film 105 is a Ti film, and an aluminum film containing Nd is layered on top of the Ti film. A three-layer structure is formed by stacking (Al-Nd) films and then depositing a Ti film on top of them. The film 105 may have a two-layer structure, or a titanium film may be laminated on an aluminum film. Furthermore, the conductive film 105 may be a single-layer structure of an aluminum film containing silicon, or a single-layer structure of a titanium film. It may also be called a structure. A cross-sectional view at this stage is shown in Figure 6(C).

[0073] Furthermore, since a contact hole 128 is formed in the gate insulating film 102, the source electric The conductive film that forms the polar layer and drain electrode layer is scanned through the contact hole 128 during deposition. Connect to line 13.

[0074] Next, a fourth photolithography step is performed to form the resist mask 131, and etching is performed. The conductive film 105 is removed by a process called a smear to form conductive layers 115a and 115b. (See Figure 7(A)). The etching method used in this case is either wet etching or dry etching. A mixing process is used. Here, a mixed gas of SiCl4, Cl2, and BCl3 is used as the reaction gas. By dry etching, the conductive film, which consists of a laminated Al-Nd film and a Ti film, is etched to create a conductive film. Layers 115a and 115b are formed.

[0075] Next, using the same resist mask 131 as for etching the conductive film 105, the second oxide semiconductor The body membrane is etched. Here, wet etching is performed using ITO07N (manufactured by Kanto Chemical Co., Ltd.). By rinsing, unnecessary parts are removed to form the second oxide semiconductor layers 114a and 114b. Note that etching here is not limited to wet etching, but also uses dry etching. It is also possible. However, depending on the etching conditions, in the etching process of the second oxide semiconductor film Therefore, the exposed region of the first oxide semiconductor layer 113 is also partially etched. The channel region of the first oxide semiconductor layer 113 between the conductive layers 114a and 114b is shown in Figure 7(A). As shown, this is a region with a thin film thickness.

[0076] Next, the resist mask 131 is removed. Also, the exposed first oxide semiconductor layer 11 Plasma treatment may be performed on the surface of 3. By performing plasma treatment, the first oxide semi-oxide Damage caused by etching of the conductive layer 113 can be repaired. Plasma treatment is O2 The process is carried out in an atmosphere containing N2O, preferably oxygen. The oxygen-containing atmosphere may include N2O, He An example of this is an atmosphere in which oxygen is added to Ar, etc. Also, C The procedure may also be carried out in an atmosphere with added l2 and CF4. Note that the plasma treatment is performed without bias. This is preferable. A cross-sectional view at this stage is shown in Figure 7(B).

[0077] Next, it is preferable to perform heat treatment at 200°C to 600°C, typically 300°C to 500°C. Here, it is placed in a furnace and heat-treated at 350°C for 1 hour under a nitrogen or atmospheric environment. This heat treatment causes atomic-level rearrangement of the In-Ga-Zn-O non-single crystal film. This heat treatment releases the strain that hinders carrier movement, thus the heat treatment here The principles (including photo-annealing) are important. Furthermore, the timing of heat treatment is crucial for oxide semiconductors. The process is not particularly limited after film deposition; for example, it may be performed after pixel electrode formation. This allows for the fabrication of a nonlinear element 170a with the first oxide semiconductor layer 113 as the channel formation region. .

[0078] Next, an interlayer insulating film 107 is formed to cover the nonlinear element 170a. Silicon nitride film, silicon oxide film, silicon oxide nitride film, obtained using methods such as the putter method. Aluminum oxide film, tantalum oxide film, etc. can be used. The lithography process uses four photomasks to create multiple nonlinear elements. (In this embodiment, the protection circuit has two nonlinear elements, 170a and 170b) It can be completed. A cross-sectional view at this stage is shown in Figure 7(C).

[0079] Following the formation of the protection circuit, the pixels of the display device were integrally formed using the same process as the nonlinear elements. Pixel electrodes are formed on a portion of the thin-film transistor. First, a fifth resist (not shown) is formed. Using a mask, the drain electrode layer of the thin-film transistor in the pixel area, which is not shown in the diagram, A contact hole is formed in the interlayer insulating film 107.

[0080] Next, after removing the resist mask, a transparent conductive film is deposited. The material for the transparent conductive film is... These include indium oxide (In2O3) and indium oxide tin oxide alloy (In2O3-SnO3). 2. Form materials such as ITO (abbreviated as ITO) using sputtering or vacuum deposition methods. Etching of materials is performed using hydrochloric acid-based solutions. However, etching of ITO in particular is Because residue is easily generated, indium oxide zinc oxide is used to improve etching processability. Gold (In2O3-ZnO) may also be used.

[0081] Next, a sixth photolithography step is performed to form a resist mask, followed by etching. Unnecessary portions of the more transparent conductive film are removed to form the pixel electrodes. Also, the gauge in the capacitance section The insulating film 102 and the interlayer insulating film 107 are used as dielectrics, and the capacitance is maintained between the capacitive wiring and the pixel electrode. It forms a transparent conductive film on the terminal portion, which is used for electrodes or wiring to connect to the FPC. Alternatively, it forms terminal electrodes for connection that function as input terminals for source wiring.

[0082] In this way, multiple thin-film transistors, integrally formed using the same process as the nonlinear element, are used to generate pixel electricity. When the poles are formed, the pixel section having an n-channel TFT and the protection circuit are fabricated simultaneously. This can be done. The second oxide semiconductor layer has higher electrical conductivity than the first oxide semiconductor layer. By creating a bonding area, stable operation becomes possible. This allows for protection circuits. This enhances the functionality and stabilizes the operation. In addition, the gate insulating film 102 is equipped with Through the tact hole 128, the scan line 13, which is formed in the same layer as the gate electrode 111, and the non By directly connecting the third terminal (drain) of the linear element 170a, the shape of the interface associated with the connection Not only can the formation be suppressed to one, but the formation of contact holes for connection can also be suppressed to one. This allows for improved protection circuit functionality and more stable operation, as well as the maintenance By reducing the area occupied by the protection circuit, it is possible to miniaturize the display device. By following the steps shown in the implementation diagram, the function of the protection circuit can be enhanced and its operation stabilized. In addition, it is for active-matrix display devices equipped with a small footprint protection circuit. It can manufacture circuit boards.

[0083] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments. That is the case.

[0084] (Embodiment 3) In this embodiment, as a display device to which one aspect of the present invention is applied, a protection circuit and The following is an example of electronic paper having thin-film transistors arranged in the pixel area.

[0085] Figure 10 shows an example of an active-matrix electronic display device to which one aspect of the present invention is applied. The paper shows the thin-film transistor 581 used in the semiconductor device, in the embodiment. It can be fabricated in the same way as the nonlinear element shown in 2, and uses an oxide semiconductor containing In, Ga, and Zn. This is a thin-film transistor with high electrical properties used in the body layer.

[0086] The electronic paper in Figure 10 is an example of a display device using a twist ball display method. The Toball display method is an electrode layer that uses spherical particles painted in white and black as display elements. It is placed between the first electrode layer and the second electrode layer, and a potential difference is applied between the first electrode layer and the second electrode layer. This method of display is achieved by controlling the orientation of spherical particles by generating a phenomenon.

[0087] Thin-film transistor 581 is a thin-film transistor with a bottom gate structure, and the insulating layer 585 Through the opening formed, the source electrode layer or drain electrode layer has electrical contact with the first electrode layer 587. It is connected to the first electrode layer 587 and the second electrode layer 588. There is a black region 590a and a sphere having a white region 590b and a cavity 594 filled with liquid around it. Particles 589 are provided, and the area around the spherical particles 589 is filled with a filler material 595 such as resin. (See Figure 10.)

[0088] Alternatively, an electrophoretic element can be used instead of a twist ball. (Transparent liquid) And, positively charged white particles and negatively charged black particles are enclosed in a diameter of 10 μm to 20 Microcapsules of approximately 0 μm are used. They are placed between the first electrode layer and the second electrode layer. The microcapsules, when an electric field is applied, are formed by the first electrode layer and the second electrode layer, and white The white and black particles move in opposite directions, allowing for the display of either white or black. An electrophoretic display element, commonly known as electronic paper, is a display element that applies this principle. Electrophoretic display elements have a higher reflectivity than liquid crystal display elements, so auxiliary lights are not required. Furthermore, it consumes little power and the display can be seen even in dimly lit places. Even if power is not supplied to the display unit, it is possible to retain the image that has been displayed. Yes. Therefore, for example, from a radio wave source that serves as a power supply to a semiconductor device with a display function (simply display) Even when a display device (also called a semiconductor device equipped with a display device) is moved away, the display It becomes possible to save the created image.

[0089] The protection circuit installed in the electronic paper manufactured through the above process is a contact for connection. In addition to reducing the occupied area by decreasing the number of occupants, it has higher electrical conductivity than the first oxide semiconductor layer. A high-efficiency second oxide semiconductor layer is provided between the first oxide semiconductor layer and the wiring layer, and the function The power is high and the operation is stable. Therefore, the power of this embodiment equipped with such a protection circuit The sub-paper is highly reliable.

[0090] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments. That is the case.

[0091] (Embodiment 4) In this embodiment, in a display device which is an example of a semiconductor device according to one aspect of the present invention, the same base The board includes at least a protection circuit, part of a drive circuit, and thin-film transistors arranged in the pixel area. Examples of the fabrication process are described below using Figures 11 to 16.

[0092] The thin-film transistors placed in the pixel area on the same substrate as the protection circuit are nonlinear as shown in Embodiment 2. It is formed in the same way as a shape element. Furthermore, the formed thin-film transistor is an n-channel type TFT. Therefore, a portion of the drive circuit that can be constructed with n-channel TFTs is defined. It is formed on the same substrate as the thin-film transistor component.

[0093] Block of an active matrix liquid crystal display device, which is an example of a semiconductor device according to one aspect of the present invention An example of the diagram is shown in Figure 11(A). The display device shown in Figure 11(A) is mounted on a substrate 5300. A pixel section 5301 having multiple pixels equipped with display elements, and a scanning line driving circuit 5 that selects each pixel. 302 and a signal line drive circuit 5303 that controls the input of the video signal to the selected pixel To possess.

[0094] The pixel section 5301 is arranged in a column direction extending from the signal line drive circuit 5303, and contains multiple signals The signal line drive circuit 5303 is connected by lines S1 to Sm (not shown), and the scan line drive circuit Multiple scan lines G1 to Gn (not shown) are arranged extending in the row direction from 5302. It is connected to the scan line drive circuit 5302 and corresponds to the signal lines S1 to Sm and scan lines G1 to Gn. It has multiple pixels (not shown) arranged in a matrix. And each pixel is Signal line Sj (one of signal lines S1 to Sm), scan line Gi (one of scan lines G1 to Gn) It will be connected to either one of the following.

[0095] Furthermore, thin-film transistors that can be formed in the same manner as the nonlinear element shown in Embodiment 2 are The diagram shows an n-channel TFT and a signal line driving circuit composed of n-channel TFTs. Let's explain using 12.

[0096] The signal line drive circuit shown in Figure 12 consists of driver IC 5601 and switch group 5602_1~56 02_M, first wiring 5611, second wiring 5612, third wiring 5613 and wiring 56 It has 21_1~5621_M. Each of the switch groups 5602_1~5602_M is, First thin-film transistor 5603a, second thin-film transistor 5603b and third thin film It has a 5603c transistor.

[0097] Driver IC 5601 has the first wire 5611, the second wire 5612, and the third wire 5613 And it is connected to wiring 5621_1~5621_M. And the switch group 5602_1~ Each of the 5602_M components is the first wiring 5611, the second wiring 5612, and the third wiring 561 Wiring 5621_1~5 corresponding to 3 and switch groups 5602_1~5602_M It is connected to 621_M. And each of the wires 5621_1~5621_M is the first Thin-film transistor 5603a, second thin-film transistor 5603b and third thin-film transistor It is connected to three signal lines via the ZISTA 5603c. For example, wiring 5621 in column J. _J (any one of the wirings 5621_1 to 5621_M) is for switch group 5602 _J has a first thin-film transistor 5603a, a second thin-film transistor 5603b and And via the third thin-film transistor 5603c, signal line Sj-1, signal line Sj, signal line S Connects to j+1

[0098] Furthermore, the first wiring 5611, the second wiring 5612, and the third wiring 5613 are each connected to a signal The number is entered.

[0099] Furthermore, it is preferable that the driver IC 5601 be formed on a single-crystal substrate. The switch groups 5602_1 to 5602_M are formed on the same substrate as the pixel section. This is desirable. Therefore, the driver IC 5601 and the switch group 5602_1~5602_ It is best to connect to M via an FPC or similar device.

[0100] Next, regarding the operation of the signal line drive circuit shown in Figure 12, please refer to the timing chart in Figure 13. Let me explain. Note that in the timing chart of Figure 13, the scan line Gi of the i-th row is selected. The timing chart shows the case where this is the case. Furthermore, the selection period of scan line Gi in row i. This is divided into a first sub-selection period T1, a second sub-selection period T2, and a third sub-selection period T3. It is divided. Furthermore, the signal line driving circuit in Figure 12 is in the case when a scan line of another row is selected. Even in combination, it operates in the same way as in Figure 13.

[0101] Note that in the timing chart of Figure 13, wiring 5621_J in column J is the first thin-film transient. Transistor 5603a, second thin-film transistor 5603b, and third thin-film transistor 560 Regarding the case where the signal lines Sj-1, Sj, and Sj+1 are connected via 3c: It is showing.

[0102] Note that the timing chart in Figure 13 shows the timing at which the scan line Gi of the i-th row is selected, and the On / off timing of 1 thin-film transistor 5603a, 5703a, 2 thin-film transistor On / off timing of transistor 5603b, 5703b, third thin-film transistor 56 The on / off timing of 03c is input to 5703c and the wiring in column J, 5621_J. This indicates signal 5721_J.

[0103] Note that wiring 5621_1 to wiring 5621_M have a first sub-selection period T1 and a second sub-selection period. During the selection period T2 and the third sub-selection period T3, different video signals are input. For example, the video signal input to wiring 5621_J during the first sub-selection period T1 is It is input to signal line Sj-1 and input to wiring 5621_J during the second sub-selection period T2. The video signal is input to signal line Sj, and during the third sub-selection period T3, wiring 5621 The video signal input to _J is input to signal line Sj+1. Furthermore, the first sub-selection period During interval T1, the second sub-selection period T2, and the third sub-selection period T3, wiring 5621_ The video signals input to J are Data_j-1, Data_j, and Data_j+ respectively. Let's set it to 1.

[0104] As shown in Figure 13, the first thin-film transistor 5603 in the first subselection period T1 When a is turned on, the second thin-film transistor 5603b and the third thin-film transistor 5603c It turns off. At this time, Data_j-1 input to wiring 5621_J is the first thin film The signal is input to the signal line Sj-1 via transistor 5603a. Second sub-selection period T2 Then, the second thin-film transistor 5603b turns on, and the first thin-film transistor 5603a And the third thin-film transistor 5603c turns off. At this time, input is input to wiring 5621_J. The data_j is input to the signal line Sj via the second thin-film transistor 5603b. During the third subselection period T3, the third thin-film transistor 5603c is turned on, and the first The thin-film transistor 5603a and the second thin-film transistor 5603b are turned off. At that time, Data_j+1 input to wiring 5621_J is transmitted to the third thin-film transistor 56 The signal is input to signal line Sj+1 via 03c.

[0105] From the above, the signal line drive circuit in Figure 12 divides the 1-gate selection period into three parts. During the 1-gate selection period, the video signal is input to three signal lines from one wiring 5621. Therefore, the signal line driving circuit in Figure 12 has the driver IC 5601 formed The number of connections between the substrate and the substrate on which the pixels are formed should be reduced to approximately 1 / 3 of the number of signal lines. This is possible. By reducing the number of connections to approximately 1 / 3, the signal line drive circuit in Figure 12 becomes reliable. It can improve performance, yield, and other factors.

[0106] Furthermore, as shown in Figure 12, the 1-gate selection period is divided into multiple sub-selection periods, and multiple sub-selection... In each selection period, video signals are input from one certain wiring to each of a plurality of signal lines If this can be done, there is no limitation on the arrangement and number of thin film transistors, the driving method, etc.

[0107] For example, in the case where video signals are input from one wiring to each of three or more signal lines in each of three or more sub selection periods respectively, thin film transistors and wirings for controlling the thin film transistors may be added. However, one gate selection period is divided into four or more sub selection periods by adding the wirings therefor. However, dividing one gate selection period into four or more sub selection periods shortens one sub selection period. Accordingly, it is preferable that one gate selection period be divided into two or three sub selection periods.

[0108] As another example, as shown in the timing chart of FIG. 14, one selection period is divided into a precharge period Tp, a first sub selection period T1, a second sub selection period T2, and a third sub selection period T 3. Further, in the timing chart of FIG. 14, the timing at which the i-th scanning line Gi is selected the on / off timing 58 03a of the first thin film transistor 5603a, the on / off timing 5803b of the second thin film transistor 5603b, and the third on / off timing 5803c of the third thin film transistor 5603c and the wiring 5 in the J-th column 621_J shows the signal 5821_J input to it. As shown in FIG. 14, in the precharge period Tp, the first thin film transistor 5603a, the second thin film transistor 56 03b and the third thin film transistor 5603c are turned on. At this time, the wiring 5621_J the precharge voltage Vp input to is supplied to the first thin film transistor 5603a and the second thin film transistor 5603b and the third thin film transistor 5603c to the signal lines S respectively through j-1, signal line Sj, and signal line Sj+1. In the first sub-selection period T1, the 1st thin film transistor 5603a is turned on, and the 2nd thin film transistor 5603b and the 3rd thin film transistor 5603c are turned off. At this time, D input to the wiring 5621_J ata_j-1 is input to the signal line Sj-1 via the first thin film transistor 5603a . In the second sub-selection period T2, the second thin film transistor 5603b is turned on, and the first thin film transistor 5603a and the third thin film transistor 5603c are turned off. This time, Data_j input to the wiring 5621_J is supplied to the second thin film transistor 5603 b and input to the signal line Sj. In the third sub-selection period T3, the third thin film transistor 5603c is turned on, and the first thin film transistor 5603a and the second thin film transistor 5603b are turned off. At this time, Data_j+1 input to the wiring 5621_J is input to the signal line Sj+1 via the third thin film transistor 5603c.

[0109] Based on the above, the signal line driving circuit of Fig.12, to which the timing chart of Fig.14 is applied, can precharge the signal lines by providing a precharge selection period before the sub-selection period, thus enabling high-speed writing of video signals to pixels. Note that in Fig.14, components similar to those in Fig.13 are denoted by the same reference numerals, and detailed description of the same portions or portions having similar functions is omitted.

[0110] Next, the configuration of a scanning line driving circuit will be described. The scanning line driving circuit includes a shift register and a buf fer. In some cases, it may also include a level shifter. The scanning line driving In the circuit, the shift register receives the clock signal (CLK) and the start pulse signal (SP). A selection signal is generated when the input ) is received. The generated selection signal is buffered It is buffered and amplified and supplied to the corresponding scan line. The scan line contains the pixels for one line. The gate electrode of the transistor is connected. And the transistor for one line of pixels Since they all need to be turned ON at once, the buffer must be capable of handling a large current. It is used.

[0111] Figures 15 and 16 illustrate one form of a shift register used in part of a scan line driving circuit. I will explain.

[0112] Figure 15 shows the circuit configuration of the shift register. It consists of multiple flip-flops, numbered 5701_1 to 5701_n. The first clock signal, the second clock signal, the start pulse signal, and the reset signal are input. It operates by being controlled.

[0113] The connection relationship of the shift register in Figure 15 will be explained. The shift register in Figure 15 is i-stage Flip-flop 5701_i (Flip-flop 5701_1~5701_n Either (i) is that the first wiring 5501 shown in Figure 16 connects to the seventh wiring 5717_i-1. The second wiring 5502 shown in Figure 16 is connected to the seventh wiring 5717_i+1. The third wiring 5503 shown in Figure 16 is connected to the seventh wiring 5717_i, as shown in Figure 16. The sixth wire 5506 is connected to the fifth wire 5715.

[0114] Furthermore, the fourth wiring 5504 shown in Figure 16 is the second wiring for odd-numbered flip-flops. connected to 5712, and in even-numbered flip-flops, connected to the third wiring 5713, the fifth wiring 5505 shown in FIG. 16 is connected to the fourth wiring 5714.

[0115] However, the first wiring 5501 shown in FIG. 16 of the first-stage flip-flop 5701_1 is the 1 wiring 5711, and the 2 wiring 5502 is connected to the sixth wiring 5716.

[0116] Note that the first wiring 5711, the second wiring 5712, the third wiring 5713, and the sixth wiring 57 16 may be referred to as a first signal line, a second signal line, a third signal line, and a fourth signal line, respectively . Further, the fourth wiring 5714 and the fifth wiring 5715 may be referred to as a first power supply line and a second power supply line, respectively.

[0117] Next, details of the flip-flop shown in FIG. 15 are illustrated in FIG. 16. The flip-flop shown in FIG. 16 includes a first thin film transistor 5571, a second thin film transistor 5572, a third thin film transistor 5573, a fourth thin film transistor 5574, a fifth thin film transisto r 5575, a sixth thin film transistor 5576, a seventh thin film transistor 5577, an d an eighth thin film transistor 5578. Note that the first thin film transistor 5571, the second thin film transistor 5572, the third thin film transistor 5573, the fourth thin film transisto r 5574, the fifth thin film transistor 5575, the sixth thin film transistor 5576, the seventh thin film transistor 5577 and the eighth thin film transistor 5578 are n-channel transistors, and are turned on when a gate-source voltage (Vgs) exceeds a threshold voltage (Vth) .

[0118] Next, the connection configuration of the flip-flops shown in Figure 16 is described below.

[0119] The first electrode (either the source electrode or the drain electrode) of the first thin-film transistor 5571 This is connected to the fourth wiring 5504 and the second electrode (saw) of the first thin-film transistor 5571. The other electrode (either the drain electrode or the other) is connected to the third wiring 5503.

[0120] The first electrode of the second thin-film transistor 5572 is connected to the sixth wiring 5506, and the second The second electrode of the thin-film transistor 5572 is connected to the third wiring 5503.

[0121] The first electrode of the third thin-film transistor 5573 is connected to the fifth wiring 5505, and the third The second electrode of thin-film transistor 5573 is the gate electrode of the second thin-film transistor 5572. The gate electrode of the third thin-film transistor 5573 is connected to the fifth wiring 5505. It will be done.

[0122] The first electrode of the fourth thin-film transistor 5574 is connected to the sixth wiring 5506, and the fourth The second electrode of thin-film transistor 5574 is connected to the gate electrode of the second thin-film transistor 5572. The gate electrode of the fourth thin-film transistor 5574 is connected to the first thin-film transistor 5 It is connected to the gate electrode of 571.

[0123] The first electrode of the fifth thin-film transistor 5575 is connected to the fifth wiring 5505, and the fifth The second electrode of thin-film transistor 5575 is the gate electrode of the first thin-film transistor 5571. The gate electrode of the fifth thin-film transistor 5575 is connected to the first wiring 5501. It will be done.

[0124] The first electrode of the sixth thin-film transistor 5576 is connected to the sixth wiring 5506, and the sixth The second electrode of thin-film transistor 5576 is the gate electrode of the first thin-film transistor 5571. The gate electrode of the sixth thin-film transistor 5576 is connected to the second thin-film transistor 5 It is connected to the gate electrode of 572.

[0125] The first electrode of the seventh thin-film transistor 5577 is connected to the sixth wiring 5506, and the seventh The second electrode of thin-film transistor 5577 is the gate electrode of the first thin-film transistor 5571. The gate electrode of the seventh thin-film transistor 5577 is connected to the second wiring 5502. The first electrode of the eighth thin-film transistor 5578 is connected to the sixth wiring 5506. The second electrode of the eighth thin-film transistor 5578 is connected to the second thin-film transistor 5572. The gate electrode of the eighth thin-film transistor 5578 is connected to the first wiring 550. It connects to 1.

[0126] Note that the gate electrode of the first thin-film transistor 5571 and the fourth thin-film transistor 5574 The gate electrode of the fifth thin-film transistor 5575, the second electrode of the sixth thin-film transistor The connection point between the second electrode of transistor 5576 and the second electrode of thin-film transistor 5577 is Let's call it code 5543. Furthermore, the gate electrode of the second thin-film transistor 5572, and the third thin-film transistor The second electrode of film transistor 5573, the second electrode of the fourth thin film transistor 5574, The gate electrode of the sixth thin-film transistor 5576 and the gate electrode of the eighth thin-film transistor 5578 The connection point of electrode 2 is designated as node 5544.

[0127] Furthermore, the first wiring 5501, the second wiring 5502, the third wiring 5503 and the fourth wiring 5 Even if we call 504 the first signal line, the second signal, the third signal line, and the fourth signal line, Good. Furthermore, connect the fifth wire 5505 to the first power line and the sixth wire 5506 to the second power line. You could call it that.

[0128] Furthermore, the signal line drive circuit and the scan line drive circuit are similarly configured together with the nonlinear elements shown in Embodiment 2. It is also possible to fabricate the TFTs using only n-channel TFTs that can be formed by this method. The n-channel TFT that can be formed in a similar manner with the nonlinear element shown in form 2 is transient Because the star's mobility is large, it becomes possible to increase the drive frequency of the drive circuit. For example, Using an n-channel TFT that can be formed in the same manner as the nonlinear element shown in Embodiment 2 The scan line drive circuit can be operated at high speed, thus increasing the frame frequency. This also allows for the insertion of black screens, among other things.

[0129] Furthermore, increasing the channel width of the transistors in the scan line driving circuit, and multiple scan lines By arranging the drive circuit and other factors, it is possible to achieve even higher frame frequencies. When multiple scan line drive circuits are arranged, a scan line drive circuit is required to drive the even-numbered scan lines. The circuitry is placed on one side, and the scan line drive circuitry for driving odd-numbered scan lines is placed on the opposite side. By placing multiple units, it is possible to increase the frame frequency. By using a scan line drive circuit, outputting signals on the same scan line is advantageous for increasing the size of the display device. ru.

[0130] Furthermore, an example of a semiconductor device to which one aspect of the present invention is applied is an active matrix type light-emitting table. When fabricating a display device, multiple thin-film transistors are arranged in at least one pixel. It is preferable to arrange multiple scan line driving circuits. Active matrix type light-emitting display device An example of a block diagram is shown in Figure 11(B).

[0131] The light-emitting display device shown in Figure 11(B) has multiple pixels equipped with display elements on a substrate 5400. A pixel section 5401, a first scan line driving circuit 5402 that selects each pixel, and a second scan line The drive circuit 5404 and the signal line drive circuit 5 control the input of the video signal to the selected pixel. It has 403.

[0132] In the case of converting the video signal input to the pixels of the light-emitting display device shown in Figure 11(B) into a digital format In total, pixels are either emitting or not emitting light by switching transistors on and off. Therefore, gradation can be displayed using area gradation or time gradation. The integrating method divides one pixel into multiple sub-pixels and drives each sub-pixel independently based on the video signal. This is a driving method that performs grayscale display by moving the pixels. Time-based grayscale display is also a method where pixels emit light... This is a driving method that performs grayscale display by controlling the duration of the operation.

[0133] Because light-emitting elements have a higher response speed compared to liquid crystal elements, they are more suitable for time-gradation methods than liquid crystal elements. Specifically, when displaying using time gradation, one frame period is divided into multiple subframes. The video signal is divided into subframes. Then, according to the video signal, the light-emitting element of each pixel in each subframe period To make the child emit light or not emit light. By dividing it into multiple subframe periods, The total length of time during which a pixel actually emits light during one frame is controlled by the video signal. It can be controlled and grayscale can be displayed.

[0134] In the light-emitting display device shown in Figure 11(B), each pixel has two switching TFTs. When arranging, the first scan line, which is the gate wiring of one of the switching TFTs, is input. The signal is generated by the first scan line drive circuit 5402, and the gate of the other switching TFT The signal input to the second scan line, which is a wire, is generated by the second scan line drive circuit 5404. The example shows the signal input to the first scan line and the signal input to the second scan line. The two may both be generated by a single scan line drive circuit. Also, for example, one image The number of switching TFTs that the element possesses determines how the operation of the switching element is controlled. It is possible that multiple scan lines may be provided for each pixel. In this case, multiple scan lines The signals input to the system may all be generated by a single scan line drive circuit, or multiple scan line drive circuits may be used to generate each scan line drive. It can also be generated using a dynamic circuit.

[0135] Furthermore, in light-emitting display devices, the drive circuit is composed of n-channel TFTs. A portion of the drive circuit can be formed on the same substrate as the thin-film transistors in the pixel section. Furthermore, the signal line drive circuit and the scan line drive circuit are the same as the nonlinear elements shown in Embodiment 2. It is also possible to fabricate the TFTs using only n-channel TFTs that can be formed by the standard method.

[0136] Furthermore, the above-mentioned drive circuit is not limited to liquid crystal displays or light-emitting displays, but also includes switching elements and It may also be used in electronic paper, which drives electronic ink using electrically connected elements. Electronic paper is also called an electrophoretic display device (electrophoretic display), and is the same as paper. Advantages include readability, lower power consumption compared to other display devices, and the ability to create a thin and light form factor. It has a point.

[0137] Electrophoretic displays can take various forms, but one involves a first particle with a positive charge. A microcapsule containing a child and a second particle having a negative charge is placed in a solvent or solute. It is a dispersed substance, and by applying an electric field to the microcapsules, micro Move the particles inside the capsule in opposite directions and display only the color of the particles that have gathered on one side. It is such that the first or second particle contains dye and, in the absence of an electric field, It does not move. Also, the color of the first particle and the color of the second particle are different (colorless). (Includes)

[0138] Thus, in electrophoretic displays, substances with high dielectric constants move to regions with high electric fields. This is a display that utilizes the so-called electrophoretic effect. Electrophoretic displays are liquid crystal displays. The polarizing plate and opposing substrate required for the display device are not needed for the electrophoresis display device, and the thickness and weight are halved. Reduce.

[0139] When the above microcapsules are dispersed in a solvent, it is called an electronic ink. This electronic ink can be printed on surfaces such as glass, plastic, fabric, and paper. Color display is also possible by using color filters or particles containing pigments.

[0140] Furthermore, the microphone is placed on the active matrix substrate, appropriately sandwiched between the two electrodes. By arranging multiple microcapsules, an active-matrix type display device can be completed. By applying an electric field to the cell, a display can be created. For example, the nonlinear element shown in Embodiment 2 Active matrices obtained by thin-film transistors that can be formed in a similar manner together with their children A stainless steel substrate can be used.

[0141] Furthermore, the first and second particles in the microcapsules are made of conductive material, insulating material, Semiconductor materials, magnetic materials, liquid crystal materials, ferroelectric materials, electroluminescent materials, electro A type of material selected from trochromic materials, magnetophoretic materials, or a composite material thereof Use it.

[0142] The protective circuit mounted on the display device manufactured through the above process has contacts for connection. In addition to reducing the number of holes and thus the occupied area, it has a higher electrical conductivity than the first oxide semiconductor layer. A high-performance oxide-second semiconductor layer is provided between the oxide-first semiconductor layer and the wiring layer. Furthermore, the operation is stable. Therefore, the display device of this embodiment equipped with such a protection circuit The placement is highly reliable.

[0143] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments. That is the case.

[0144] (Embodiment 5) In one embodiment of the present invention, a thin-film transistor is fabricated together with a nonlinear element, and the thin-film transistor A semiconductor device (also called a display device) that uses a star in the pixel section and further in the driving circuit to have a display function. (u) can be fabricated. In one embodiment of the present invention, a nonlinear element and a thin film transistor can be fabricated. The zista is used as part or all of the drive circuit and is integrally formed on the same substrate as the pixel section, and the system On-panel formation is possible.

[0145] A display device includes display elements. Display elements include liquid crystal elements (also called liquid crystal display elements) and light-emitting elements. A light-emitting element (also called a light-emitting display element) can be used. The light-emitting element is activated by current or voltage. This category includes elements whose brightness is controlled, specifically inorganic EL (Electrical LEDs). This includes Luminescence, organic EL, etc. Also, electronic inks, etc. Display media in which contrast changes due to the effect can also be applied.

[0146] Furthermore, the display device includes a panel in which the display elements are sealed, and a controller on the panel. The invention includes a module on which ICs and the like are mounted. Furthermore, one aspect of the present invention includes the table Regarding the element substrate, which is a form of the display element before it is completed in the process of manufacturing a display device. Furthermore, the element substrate is provided with means for supplying current to the display element in each of the multiple pixels. Specifically, the substrate may be in a state where only the pixel electrodes of the display element are formed, or the pixels This is the state after the conductive film that will serve as the electrode has been deposited, but before etching to form the pixel electrode. It's fine if it exists, and all forms are applicable.

[0147] In this specification, the term "display device" refers to an image display device, a display device, or an optical display device. This refers to the power source (including lighting equipment). It also refers to connectors, such as FPC (Flexible Printed Circuit). (inted circuit) or TAB (Tape Automated Bon (ding) tape or TCP (Tape Carrier Package) Modules that have a printed circuit board attached to the end of the TAB tape or TCP. The display element or IC (integrated circuit board) is integrated using the COG (Chip On Glass) method. All modules in which the road is directly implemented are also included in the display device.

[0148] In this embodiment, the appearance of a liquid crystal display panel corresponding to one form of the display device according to one aspect of the present invention. The cross-section will be explained using Figure 17. Figures 17(A1)(A2) show the nonlinear element and Similarly, an oxide semiconductor containing In, Ga, and Zn formed on the first substrate 4001 is semi-semi High electrical properties thin-film transistors 4010, 4011, and liquid crystal element 40 used in the conductive layer The top surface of the panel, 13 is sealed between it and the second substrate 4006 by a sealing material 4005. This is a diagram, and Figure 17(B) corresponds to the cross-sectional view at MN in Figures 17(A1) and (A2). .

[0149] The pixel section 4002 and the scanning line driving circuit 4004 are surrounded on the first substrate 4001. A sealing material 4005 is provided in this manner. Also, the pixel section 4002 and the scan line drive rotation A second substrate 4006 is provided on the path 4004. Therefore, the pixel section 4002 and the scanning The line drive circuit 4004 consists of the first substrate 4001, the sealing material 4005, and the second substrate 4006. It is sealed together with the liquid crystal layer 4008. Also, the seal on the first substrate 4001 A single crystal is placed on a separately prepared substrate in a region different from the area enclosed by material 4005. A signal line driving circuit 4003, formed from a semiconductor film or a polycrystalline semiconductor film, is mounted.

[0150] Furthermore, the method of connecting the separately formed drive circuit is not particularly limited, and COG method, Wire bonding methods or TAB methods can be used. Figure 17(A1) This is an example of implementing the signal line drive circuit 4003 using the COG method, and Figure 17(A2) shows that This is an example of implementing the signal line drive circuit 4003 using the TAB method.

[0151] Furthermore, the pixel section 4002 and the scanning line driving circuit 4004 provided on the first substrate 4001 are, It has multiple thin-film transistors, and in Figure 17(B), the thin film included in the pixel section 4002 Transistor 4010 and thin-film transistor 4011 included in scan line drive circuit 4004 The following is an example. On thin-film transistors 4010 and 4011 are insulating layers 4020 and 402 1 is provided.

[0152] Thin-film transistors 4010 and 4011 use an oxide semiconductor containing In, Ga, and Zn. This corresponds to a thin-film transistor with high electrical characteristics used in the conductive layer, and is a nonlinear element as shown in Embodiment 2. Thin-film transistors that can be formed in a similar manner can also be applied to the child. In this context, thin-film transistors 4010 and 4011 are n-channel thin-film transistors. .

[0153] Furthermore, the pixel electrode layer 4030 of the liquid crystal element 4013 is connected to the thin-film transistor 4010. They are electrically connected. And the counter electrode layer 4031 of the liquid crystal element 4013 is on the second substrate 40 Formed on 06. Pixel electrode layer 4030, counter electrode layer 4031, and liquid crystal layer 4008 The overlapping portion corresponds to the liquid crystal element 4013. Note that the pixel electrode layer 4030 and the opposite The electrode layer 4031 is provided with insulating layers 4032 and 4033, which function as alignment films. The liquid crystal layer 4008 is sandwiched between insulating layers 4032 and 4033.

[0154] The first substrate 4001 and the second substrate 4006 are made of glass, metal (typically, glass). Stainless steel, ceramics, and plastics can be used. , FRP (Fiberglass-Reinforced Plastics) board, PV F (polyvinyl fluoride) film, polyester film, polyester film Alternatively, acrylic resin film can be used. Also, aluminum foil can be used with PVF. It is also possible to use sheets with a structure that is sandwiched between films or polyester films.

[0155] Furthermore, 4035 is a columnar spacer obtained by selectively etching an insulating film. To control the distance (cell gap) between the pixel electrode layer 4030 and the counter electrode layer 4031 It is provided in [location]. A spherical spacer may also be used.

[0156] Alternatively, a liquid crystal exhibiting a blue phase without an alignment layer may be used. The blue phase is one of the liquid crystal phases. Yes, as the temperature of a cholesteric liquid crystal is increased, it transitions from the cholesteric phase to the isotropic phase. This is the phase that appears earlier. The blue phase only appears within a narrow temperature range, so improving the temperature range is necessary. To achieve this, a liquid crystal composition containing 5% or more by weight of a chiral agent is used in the liquid crystal layer 4008. It is used. A liquid crystal composition containing a liquid crystal exhibiting a blue phase and a chiral agent has a response speed of 10 μs~ With a short duration of 100 μs and optical isotropy, orientation processing is unnecessary, and it exhibits low field-of-view angle dependence. stomach.

[0157] Although this embodiment is an example of a transmissive liquid crystal display device, one aspect of the present invention relates to a reflective liquid crystal display device. It can be applied to both devices and semi-transmissive liquid crystal display devices.

[0158] Furthermore, in the liquid crystal display device of this embodiment, a polarizing plate is provided on the outside (viewing side) of the substrate, and on the inside An example is shown where the colored layer and the electrode layer used for the display element are arranged in that order, but the polarizing plate is placed on the inside of the substrate. It may also be done. Furthermore, the laminated structure of the polarizing plate and the colored layer is not limited to this embodiment, and the polarizing plate and The coloring layer and the manufacturing process conditions should be set appropriately. A light-shielding film that functions in this way may be provided.

[0159] Furthermore, in this embodiment, in order to reduce surface irregularities of the thin-film transistor, and thin-film transistor To improve the reliability of the zista, the nonlinear element shown in Embodiment 2, along with the nonlinear element, Thin-film transistors that can be formed in a similar manner can function as insulating layers that act as protective films or planarizing insulating films. The structure is covered with insulating layers (4020 and 4021). The protective film is in the atmosphere. It is designed to prevent the entry of contaminants such as floating organic matter, metallic substances, and water vapor. A dense film is preferred. The protective film is made using the sputtering method, consisting of a silicon oxide film, a silicon nitride film, and an oxidative nitride film. Silicon film, silicon nitride film, aluminum oxide film, aluminum nitride film, aluminum oxide nitride film This embodiment may be formed by a single layer or a stack of aluminum oxide or aluminum nitride films. Now, let's look at an example of forming a protective film using the sputtering method, but it is not limited to this method and can be formed using various other methods. good.

[0160] Here, a laminated insulating layer 4020 is formed as a protective film. As the first layer of 0, a silicon oxide film is formed using the sputtering method. Silicon oxide film as a protective layer. Using this method, hillock prevention of aluminum films used as source electrode layer and drain electrode layer is achieved. It is effective in stopping it.

[0161] Furthermore, an insulating layer is formed as the second layer of the protective film. Here, the second layer of the insulating layer 4020 is Then, a silicon nitride film is formed using the sputtering method. When a silicon nitride film is used as a protective film, This refers to the intrusion of mobile ions such as thorium into the semiconductor region, thereby altering the electrical properties of the TFT. It can be suppressed.

[0162] Furthermore, after forming the protective film, the oxide semiconductor layer is annealed (300°C to 400°C). That's fine.

[0163] Furthermore, an insulating layer 4021 is formed as a planar insulating film. The insulating layer 4021 is made of poly Heat-resistant organic materials such as mids, acrylics, benzocyclobutenes, polyamides, and epoxys. Materials can be used. In addition to the above organic materials, low dielectric constant materials (low-k materials) can also be used. Using siloxane-based resins, PSG (phosphorus glass), BPSG (phosphorus boron glass), etc. It is possible. Siloxane resins can have hydrogen, fluorine, alkyl groups, or other substituents. It may have at least one of the reel groups. Furthermore, the insulating material formed from these materials An insulating layer 4021 may be formed by laminating multiple edge films.

[0164] Siloxane-based resins are formed using siloxane-based materials as the starting material for Si-OS. This corresponds to a resin containing i-bonds. Siloxane resins have hydrogen as a substituent, as well as fluorine and alkyl It may have at least one of the following: a ru group or an aromatic hydrocarbon.

[0165] The method for forming the insulating layer 4021 is not particularly limited and can be sputtered or SOG depending on the material. Spin coating, dip coating, spray coating, droplet ejection (inkjet method, screen coating) Printing, offset printing, etc.), doctor knife, roll coater, curtain coater, knife A coater or the like can be used. When forming the insulating layer 4021 using a material liquid, During the machining process, the oxide semiconductor layer can also be annealed (300°C to 400°C). By combining the firing process of the insulating layer 4021 and the annealing of the oxide semiconductor layer, the semiconductor is efficiently manufactured. It becomes possible to fabricate a body device.

[0166] The pixel electrode layer 4030 and the counter electrode layer 4031 are made of indium oxide containing tungsten oxide. , indium zinc oxide containing tungsten oxide, indium oxide containing titanium oxide, Titanium oxide-containing indium tin oxide, indium tin oxide (hereinafter referred to as ITO), Translucent materials such as indium zinc oxide and indium tin oxide with added silicon dioxide. Conductive materials can be used.

[0167] Furthermore, conductive polymers are used as the pixel electrode layer 4030 and the counter electrode layer 4031. It can be formed using a conductive composition containing (also known as). The resulting pixel electrodes have a sheet resistance of 10,000 Ω / □ or less and a light transmittance at a wavelength of 550 nm. It is preferable that the ratio is 70% or more. Also, the resistance of the conductive polymer contained in the conductive composition The ratio is preferably 0.1 Ω·cm or less.

[0168] As the conductive polymer, so-called π-electron conjugated conductive polymers can be used. For example For example, polyaniline or its derivatives, polypyrrole or its derivatives, polythiophene Examples include derivatives thereof, or copolymers of two or more of these.

[0169] In addition, a separately formed signal line drive circuit 4003 and a scan line drive circuit 4004 or pixel unit 4 The various signals and potentials supplied to 002 are provided by the FPC4018.

[0170] In this embodiment, the connection terminal electrode 4015 is connected to the pixel electrode layer 40 of the liquid crystal element 4013. Formed from the same conductive film as 30, the terminal electrode 4016 is made of thin-film transistor 4010, 40 The source electrode layer and drain electrode layer are formed of the same conductive film.

[0171] The connecting terminal electrode 4015 is connected to the terminal of the FPC 4018 via the anisotropic conductive film 4019. They are electrically connected.

[0172] Furthermore, in Figure 17, a signal line drive circuit 4003 is formed separately and implemented on the first substrate 4001. Although an example of the configuration is shown, this embodiment is not limited to this configuration. Scan line drive circuit Alternatively, it may be formed and implemented separately, or it may be part of the signal line drive circuit or part of the scan line drive circuit. It is also acceptable to form and implement the component separately.

[0173] Figure 18 shows a semiconductor device using a TFT substrate 2600 manufactured by applying one aspect of the present invention. This shows an example of how a liquid crystal display module is configured.

[0174] Figure 18 shows an example of a liquid crystal display module, in which the TFT substrate 2600 and the opposing substrate 2601 are The pixel portion 2603, which includes a TFT and the like, is fixed in place by a material 2602, and the liquid crystal layer is also included between them. A display element 2604 and a colored layer 2605 are provided to form a display area. Colored layer 2605 This is necessary for color display, and in the case of the RGB method, it corresponds to red, green, and blue. A colored layer is provided corresponding to each pixel. The TFT substrate 2600 and the opposing substrate 2601 Polarizing plates 2606, 2607, and 2613 are arranged on the outside. The light source is cold It consists of a cathode tube 2610 and a reflector 2611, and the circuit board 2612 is flexible The wiring circuit section 2608 of the TFT board 2600 is connected by the wire board 2609, and the control External circuits such as polarizing circuits and power supply circuits are incorporated. Also, between the polarizing plate and the liquid crystal layer The layers may be stacked with a phase difference plate in place.

[0175] The LCD display module has TN (Twisted Nematic) mode and IPS (I n-Plane-Switching) mode, FFS (Fringe Field Switching) (witching) mode, MVA (Multi-domain Vertical A) 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 C (rystal) mode, AFLC (AntiFerroelectric Liquid) Crystals and other materials can be used.

[0176] The protection circuit mounted on the liquid crystal panel manufactured through the above process is a contact for connection In addition to reducing the number of holes and thus the occupied area, it has a higher electrical conductivity than the first oxide semiconductor layer. A high-performance second oxide semiconductor layer is provided between the first oxide semiconductor layer and the wiring layer, and the function High performance and stable operation. Therefore, the liquid crystal of this embodiment equipped with such a protection circuit. The panel is highly reliable.

[0177] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments. That is the case.

[0178] (Embodiment 6) In one embodiment of the present invention, a thin-film transistor is fabricated together with a nonlinear element, and the thin-film transistor A semiconductor device (also called a display device) that uses a star in the pixel section and further in the driving circuit to have a display function. It is possible to produce (u).

[0179] In this embodiment, an example of a light-emitting display device is shown as a display device according to one aspect of the present invention. As an example of a display element, here we will use a light-emitting element that utilizes electroluminescence. This demonstrates that light-emitting devices utilizing electroluminescence use organic compounds as their light-emitting material. They are distinguished by whether they are organic or inorganic compounds; generally, the former are organic EL elements, and the latter are inorganic. It is called an EL element.

[0180] Organic EL elements emit electrons and holes from a pair of electrodes when a voltage is applied to the light-emitting element. Each of these is injected into a layer containing a luminescent organic compound, and an electric current flows through it. Then, these... The recombination of electrons and holes causes the luminescent organic compound to form an excited state. And when that excited state returns to the ground state, it emits light. From this mechanism, Such light-emitting devices are called current-excited light-emitting devices.

[0181] Inorganic electroluminescent (EL) elements are classified into dispersed inorganic EL elements and thin-film inorganic EL elements based on their element configuration. They are classified as such. Dispersive inorganic EL elements have a light-emitting layer in which particles of light-emitting material are dispersed in a binder. The luminescence mechanism utilizes donor and acceptor levels, and the donor-acceptor level is the key to this process. This is a receptor recombination type light emission. Thin-film inorganic EL elements sandwich the light-emitting layer between dielectric layers. Furthermore, it has a structure where it is sandwiched between electrodes, and the light emission mechanism utilizes the inner-shell electron transition of metal ions. This is a localized light emission. Here, we will explain using an organic EL element as the light-emitting element. ru.

[0182] Figure 19 shows an example of a semiconductor device to which one aspect of the present invention is applied, specifically digital time-gradation driving. This figure shows an example of a possible pixel configuration.

[0183] This section describes the pixel configuration and operation to which digital time-based gradation driving can be applied. This is an oxide semiconductor layer that can be formed in a channel shape in the same way as the nonlinear element shown in Embodiment 2. This example shows the use of two n-channel transistors in a single pixel for the region being constructed.

[0184] Pixel 6400 consists of a switching transistor 6401, a driving transistor 6402, It has a light-emitting element 6404 and a capacitive element 6403. Switching transistor 64 01 has a gate connected to scan line 6406, and the first electrode (source electrode and drain electrode) The (side) is connected to signal line 6405, and the second electrode (the other of the source electrode and drain electrode) is driven It is connected to the gate of the drive transistor 6402. The drive transistor 6402 is The gate is connected to the power line 6407 via the capacitive element 6403, and the first electrode is connected to the power line 640 It is connected to 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.

[0185] Furthermore, a low power supply potential is set for the second electrode (common electrode 6408) of the light-emitting element 6404. The low power supply potential is defined as the low power supply potential set on power line 6407 relative to the high power supply potential. The potential is the potential that satisfies the high power supply potential, and low power supply potentials include, for example, GND and 0V. It may be fixed. The potential difference between this high power supply potential and the low power supply potential is applied to the light-emitting element 6404. Then, in order to pass current through the light-emitting element 6404 and make the light-emitting element 6404 emit light, a high power supply potential is used. The potential difference between the low power supply potential and the light-emitting element 6404 is set to be greater than or equal to the forward threshold voltage of the light-emitting element 6404. Set the potential for each.

[0186] Note that the capacitive element 6403 is omitted by substituting the gate capacitance of the drive transistor 6402. This is also possible. Regarding the gate capacitance of the drive transistor 6402, the channel region A capacitance may be formed between the gate electrode and the gate electrode.

[0187] In the case of a voltage input / voltage drive method, the gate of the drive transistor 6402 is: The drive transistor 6402 is either fully on or completely off. The video signal is input. In other words, the driver transistor 6402 is operated in the linear region. The driver transistor 6402 operates in the linear region, therefore the voltage of the power line 6407 is higher than A high voltage is applied to the gate of the drive transistor 6402. The signal line 6405 is connected to... Apply a voltage equal to or greater than (power line voltage + Vth of the drive transistor 6402).

[0188] Furthermore, when using analog gradation drive instead of digital time gradation drive, the signal input is different. By doing so, the same pixel configuration as in Figure 19 can be used.

[0189] When performing analog grayscale driving, the gate of the driving transistor 6402 is connected to the light-emitting element 6404 Apply a voltage equal to or greater than the forward voltage of the drive transistor 6402 + Vth. (Light-emitting element 64) The forward voltage of 04 refers to the voltage required to achieve the desired brightness, and at least the forward voltage is Includes key voltage. Note that the drive transistor 6402 operates in the saturation region. By inputting an O signal, current can be supplied to the light-emitting element 6404. The drive transistor... To operate the 6402 in the saturation region, the potential of the power line 6407 is set to the drive transistor The gate potential of the TA6402 is set higher. By making the video signal analog, the light-emitting element... By supplying current to the 6404 according to the video signal, analog grayscale driving can be performed.

[0190] Note that the pixel configuration shown in Figure 19 is not limited to this. For example, if new pixels are added to the pixels shown in Figure 19... Switches, resistors, capacitives, transistors, or logic circuits may be added to it.

[0191] Next, the configuration of the light-emitting element will be explained using Figure 20. Here, the driving TFT is n The cross-sectional structure of a pixel will be explained using the case of a type as an example. Figure 20(A)(B)(C) The TFT7001, 7011, and 7021, which are driver TFTs used in semiconductor devices, are actually This is a thin-film transistor that can be formed in the same manner as the nonlinear element shown in the second embodiment of the method, Thin film transients with high electrical properties using oxide semiconductors containing n, Ga, and Zn as semiconductor layers. He is a star.

[0192] A light-emitting element only needs to have at least one of its electrodes, either the anode or the 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 emitted from the side opposite to the substrate. This includes top-side emission, bottom-side emission which extracts light from the substrate side, and on the substrate side and the opposite side of the substrate. There is a light-emitting element with a double-sided emission structure that extracts light from the side surface, and the pixel configuration in one aspect of the present invention is It can be applied to any light-emitting element with an injection structure.

[0193] The light-emitting element with an upper surface injection structure will be explained using Figure 20(A).

[0194] Figure 20(A) shows that the driving TFT, TFT7001, is of n type, and the light-emitting element 7002 emits This shows a cross-sectional view of a pixel when the light being emitted passes through to the anode 7005 side. In Figure 20(A), The cathode 7003 of the light-emitting element 7002 and the driving TFT, TFT7001, are electrically connected. The cathode 7003 has a light-emitting layer 7004 and an anode 7005 stacked on top of it in that order. 7003 uses a variety of materials as long as the work function is small and the conductive film reflects light. This is possible. For example, Ca, Al, MgAg, AlLi, etc. are desirable. And the light-emitting layer 7 Whether 004 consists of a single layer or is configured with multiple layers stacked on top of each other Either is fine. If it consists of multiple layers, the electron injection layer is on the cathode 7003, and the electron transport layer is on top of the cathode 7003. The layers are stacked in the following order: transport layer, light-emitting layer, hole transport layer, and hole injection layer. There is no need to do so. The anode 7005 is formed using a conductive material that is translucent and transmits light. For example, indium oxide containing tungsten oxide, indium oxide containing tungsten oxide Lead oxide, indium oxide containing titanium oxide, indium tin oxide containing titanium oxide, Indium tin oxide (hereinafter referred to as ITO), indium zinc oxide, and silicon oxide are added. A transparent conductive film, such as an indium tin oxide, may also be used.

[0195] The region between the cathode 7003 and the anode 7005, which sandwiches the light-emitting layer 7004, is the light-emitting element 7002. It corresponds to the pixel shown in Figure 20(A), where the light emitted from the light-emitting element 7002 is the arrow. As indicated by the mark, inject towards the anode 7005 side.

[0196] Next, the light-emitting element with a bottom-extrusion structure will be explained using Figure 20(B). Driving TFT7 When 011 is n-type and the light emitted from the light-emitting element 7012 is directed toward the cathode 7013 side, Figure 20(B) shows a cross-sectional view of the pixel. In Figure 20(B), the driving TFT7011 is electrically connected to the pixel. The cathode 7013 of the light-emitting element 7012 is deposited on a light-transmitting conductive film 7017. The light-emitting layer 7014 and the anode 7015 are stacked in order on the cathode 7013. If 015 is translucent, a shielding material to reflect or block light should be used to cover the anode. A film 7016 may be formed. The cathode 7013 is as in the case of Figure 20(A). Various materials can be used if the conductivity function is small. However, the film thickness is The film should be transparent enough to transmit light (preferably around 5 nm to 30 nm). For example, a 20 nm film. A thick aluminum film can be used as the cathode 7013. And the light-emitting layer 7 014, as in Figure 20(A), consists of a single layer, but multiple layers are stacked on top of each other. Either configuration is acceptable. The anode 7015 does not need to transmit light, but as shown in the diagram... Similar to 20(A), it can be formed using a light-transmitting conductive material. The shielding film 7016 can be made of, for example, a light-reflecting metal, but is not limited to a metal film. It's not possible. For example, a resin with black pigment added can be used.

[0197] The region between the cathode 7013 and anode 7015, sandwiching the light-emitting layer 7014, is the light-emitting element 7012. This corresponds to the pixel shown in Figure 20(B), where the light emitted from the light-emitting element 7012 is As indicated by the arrow, the material is injected towards the cathode 7013.

[0198] Next, a light-emitting element with a double-sided injection structure will be explained using Figure 20(C). Figure 20(C) Then, on the light-transmitting conductive film 7027 electrically connected to the driving TFT 7021, The cathode 7023 of the light-emitting element 7022 is formed by depositing a film, and the light-emitting layer 7024 is on the cathode 7023. The anodes 7025 are stacked in order. The cathode 7023 is, as in the case of Figure 20(A), Various materials can be used if the conductivity function is small. However, the film thickness is ...to the extent that it transmits light. For example, Al with a film thickness of 20 nm is used as cathode 7023. It can be used. The light-emitting layer 7024 is composed of a single layer, as in Figure 20(A). It is acceptable whether it is configured as a single layer or as multiple layers stacked on top of each other. Anode 70 25 is formed using a light-transmitting conductive material, similar to Figure 20(A). It is possible.

[0199] The portion where the cathode 7023, the light-emitting layer 7024, and the anode 7025 overlap is the light-emitting element 70 This corresponds to 22. In the case of the pixel shown in Figure 20(C), the light emitted from the light-emitting element 7022 As indicated by the arrows, the material is injected into both the anode 7025 side and the cathode 7023 side.

[0200] Here, we have discussed organic EL elements as light-emitting elements, but inorganic EL elements can also be used as light-emitting elements. It is also possible to incorporate an L element.

[0201] In this embodiment, a thin-film transistor (driving TFT) controls the driving of the light-emitting element, An example of electrically connected light-emitting elements was shown, but current is currently flowing between the driving TFT and the light-emitting element. A configuration in which a control TFT is connected is also acceptable.

[0202] The semiconductor device shown in this embodiment is not limited to the configuration shown in Figure 20. Various modifications are possible based on the technical concept of one aspect of the present invention.

[0203] Next, a light-emitting display panel (also known as a light-emitting panel) corresponding to one form of the semiconductor device according to one aspect of the present invention. The appearance and cross-section of the invention will be explained using Figure 21. Figure 21(A) shows the invention Similar to the nonlinear element in the embodiment, an oxide semiconductor containing In, Ga, and Zn is used as the semiconductor layer. The thin-film transistors and light-emitting elements with high electrical properties used are placed between the second substrate and a sealing material. Therefore, Figure 21(B) is a top view of the sealed panel, and in Figure 21(A) HI This corresponds to a cross-sectional view.

[0204] Pixel section 4502, signal line driving circuit 4503a, 450 provided on the first substrate 4501 3b, and the scan line drive circuits 4504a and 4504b are surrounded by a sealing material 4505 A pixel unit 4502, signal line driving circuits 4503a, 4503b, and A second substrate 4506 is provided on top of the scan line driving circuits 4504a and 4504b. The pixel section 4502, signal line driving circuits 4503a, 4503b, and scan line driving circuit 45 04a and 4504b consist of a first substrate 4501, a sealing material 4505, and a second substrate 4506. It is sealed together with the filler 4507. Highly dense protective film with minimal degassing (laminated film, UV-curing resin film) It is preferable to package (seal) the product with a cover material such as a linoleum.

[0205] Also provided on the first substrate 4501 are the pixel section 4502, the signal line driving circuit 4503a, 4 503b, and the scan line driving circuits 4504a and 4504b have multiple thin-film transistors. In Figure 21(B), the thin-film transistor 4510 included in the pixel section 4502 and the signal The thin-film transistor 4509 included in the wire drive circuit 4503a is shown as an example.

[0206] Thin-film transistors 4509 and 4510 use an oxide semiconductor containing In, Ga, and Zn. This corresponds to a thin-film transistor with high electrical characteristics used in the conductive layer, and is a nonlinear element as shown in Embodiment 2. Thin-film transistors that can be formed in a similar manner to those used in this embodiment can be applied. In this state, thin-film transistors 4509 and 4510 are n-channel thin-film transistors. ru.

[0207] Furthermore, 4511 corresponds to a light-emitting element, and the first electrode is a pixel electrode of the light-emitting element 4511. Layer 4517 is electrically connected to the source electrode layer or drain electrode layer of the thin-film transistor 4510. It is connected to the following. The configuration of the light-emitting element 4511 is a first electrode layer 4517 and an electroluminescent layer The stacked structure consists of 4512 and a second electrode layer 4513, but is not limited to the configuration shown in this embodiment. It is not done. The direction of the light emitted from the light-emitting element 4511 is adjusted according to the direction of the light emitted from the light-emitting element 4511. The configuration can be changed as needed.

[0208] The partition wall 4520 is formed using an organic resin film, an inorganic insulating film, or an organic polysiloxane. In particular, using a photosensitive material, an opening is formed on the first electrode layer 4517, and the side wall of the opening It is preferable to form it so that it becomes an inclined surface with a continuous curvature.

[0209] Even if the electroluminescent layer 4512 consists of a single layer, it is configured to be stacked with multiple layers. It's fine either way.

[0210] To prevent oxygen, hydrogen, moisture, carbon dioxide, etc. from entering the light-emitting element 4511, the second electrode layer A protective film may be formed on 4513 and the partition wall 4520. The protective film may be a silicon nitride film. It can form silicon nitride oxide films, DLC films, and the like.

[0211] Also, signal line drive circuits 4503a, 4503b and scan line drive circuits 4504a, 4504b The various signals and potentials applied to the pixel section 4502 are FPC4518a, 4518 It is supplied by b.

[0212] In this embodiment, the connection terminal electrode 4515 is connected to the first electrode layer 4 of the light-emitting element 4511. Formed from the same conductive film as 517, terminal electrode 4516 is thin-film transistor 4509, 4 It is formed from the same conductive film as the source electrode layer and drain electrode layer of 510.

[0213] The connecting terminal electrode 4515 is connected to the terminal of FPC4518a via the anisotropic conductive film 4519. They are electrically connected.

[0214] The second substrate located in the direction of light extraction from the light-emitting element 4511 must be translucent. No. In that case, glass plate, plastic plate, polyester film or acrylic A light-transmitting material, such as a film, is used.

[0215] Furthermore, in addition to inert gases such as nitrogen and argon, UV-curable resin can also be used as the filler 4507. Oils or thermosetting resins can be used, such as PVC (polyvinyl chloride), acrylic, Polyimide, epoxy resin, silicone resin, PVB (polyvinyl butyral) or EV A (ethylene vinyl acetate) can be used. In this embodiment, nitrogen is used as a filler. I used a prime element.

[0216] Furthermore, if necessary, a polarizing plate or circular polarizing plate (including elliptical polarizing plate) may be placed on the emission surface of the light-emitting element. You may also appropriately incorporate optical films such as phase difference plates (λ / 4 plate, λ / 2 plate) and color filters. Furthermore, an anti-reflective coating may be provided on the polarizing plate or circular polarizing plate. For example, by the surface irregularities An anti-glare treatment can be applied to diffuse reflected light and reduce glare.

[0217] The signal line drive circuits 4503a and 4503b, and the scan line drive circuits 4504a and 4504b are Drive turns formed by a single-crystal semiconductor film or polycrystalline semiconductor film on a separately prepared substrate It may be implemented in the circuit. Also, only the signal line drive circuit, or part of it, or the scan line drive circuit The road may be formed separately or partially, and this embodiment is configured as shown in Figure 21. Not limited.

[0218] The protective circuit installed in the light-emitting display device (display panel) manufactured through the above process is connected In addition to reducing the number of contact holes and thus the occupied area, the first oxide semiconductor layer A second oxide semiconductor layer with higher electrical conductivity is placed between the first oxide semiconductor layer and the wiring layer. It is equipped with a protective circuit, has high functionality, and operates stably. Therefore, this book equipped with such a protective circuit The light-emitting display device (display panel) of this embodiment is highly reliable.

[0219] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments. That is the case.

[0220] (Embodiment 7) A display device according to one aspect of the present invention can be applied as electronic paper. It can be used in electronic devices in any field that display information. For example, using e-paper, you can display e-books, posters, and images on trains and other vehicles. This can be applied to in-vehicle advertising, displays on various cards such as credit cards, etc. Examples of sub-devices are shown in Figures 22 and 23.

[0221] Figure 22(A) shows poster 2631 made with electronic paper. In the case of printed materials, the exchange of advertisements is done manually, but one aspect of the present invention applies Using electronic paper, the advertisement display can be changed in a short amount of time. Also, the display does not break down. A stable image can be obtained without any issues. Furthermore, the poster is configured to transmit and receive information wirelessly. That is also acceptable.

[0222] Figure 22(B) also shows in-vehicle advertisements 2632 on trains and other vehicles. In the case of printed paper, advertisements are changed manually, but one aspect of the present invention is suitable By using electronic paper, it is possible to change the advertisement display in a short time without requiring much manpower. This is possible. Furthermore, a stable image can be obtained without any display distortion. Note that in-car advertising is wireless. It may also be configured to allow information to be sent and received.

[0223] Figure 23 also shows an example of eBook 2700. For example, eBook 2700 is, It consists of two enclosures, enclosure 2701 and enclosure 2703. Enclosure 2701 and enclosure The body 2703 is integrated with the shaft portion 2711, and opens and closes around the shaft portion 2711 as an axis. It is possible to perform operations. This configuration makes it possible to operate like a paper book. This is the result.

[0224] The display unit 2705 is incorporated into the housing 2701, and the display unit 2707 is incorporated into the housing 2703. It is included. Display units 2705 and 2707 are configured to display a continuation screen. Alternatively, a configuration that displays different screens is also acceptable. For example, text is displayed on the right-hand display unit (display unit 2705 in Figure 23), and the left-hand display unit An image can be displayed on the display unit 2707 in Figure 23.

[0225] Furthermore, Figure 23 shows an example in which the housing 2701 is equipped with an operating unit, etc. For example, housing 2 Unit 701 is equipped with a power supply 2721, operation keys 2723, speaker 2725, and the like. The page can be turned using operation key 2723. Note that the key is located on the same side as the display unit of the casing. It may also be configured to include a board or pointing device. Furthermore, the back of the enclosure or On the side, there are external connection terminals (earphone jack, USB terminal, or AC adapter and USB A configuration that includes terminals that can connect to various cables such as cables, a recording medium insertion section, and so on. It may also be done this way. Furthermore, the eBook 2700 is configured to have the functionality of an electronic dictionary. That's fine.

[0226] Furthermore, the e-book 2700 may be configured to transmit and receive information wirelessly. By wireless means, The system will be configured to allow users to purchase and download desired book data from an e-book server. It is also possible.

[0227] The protective circuit mounted in the display device of this embodiment reduces the number of contact holes for connection. In addition to reducing the occupied area, the second oxide has higher electrical conductivity than the first oxide semiconductor layer. The oxide semiconductor layer is placed between the first oxide semiconductor layer and the wiring layer, resulting in high functionality and stable operation. The display device of this embodiment, which is equipped with such a protection circuit, is highly reliable.

[0228] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments. That is the case.

[0229] (Embodiment 8) A semiconductor device according to one aspect of the present invention can be applied to various electronic devices (including amusement machines). This can be done. As for electronic devices, for example, television equipment (television, or television) (Also called a receiver), computer monitors, digital cameras, digital video cameras Camera, digital photo frame, mobile phone (also called mobile phone or mobile phone device), mobile Examples include small game consoles, portable information terminals, sound playback devices, and large game machines such as pachinko machines. It can be done.

[0230] Figure 24(A) shows an example of the television equipment 9600. In the case of 00, the display unit 9603 is incorporated into the housing 9601. The display unit 9603 displays It is possible to display an image. Also, here, the stand 9605 is used to display the housing 9601 This shows a configuration that supports this.

[0231] The television unit 9600 is operated using the control switches on the housing 9601 and a separate remote control. This can be done using the control unit 9610. The remote control unit 9610 has control keys The 9609 allows you to control the channel and volume, and the information is displayed on the display unit 9603. The video can be controlled. Furthermore, the remote control unit 9610 can be controlled by the remote control unit. A display unit 9607 may be provided to display the information output from 9610.

[0232] The television system 9600 will consist of a receiver, modem, and other components. It can receive more general television broadcasts, and furthermore, it can connect via a modem, either wired or wirelessly. By connecting to the communication network, one-way (sender to receiver) or two-way communication is possible. It is also possible to communicate information (between a sender and a receiver, or between receivers, etc.).

[0233] Figure 24(B) shows an example of the digital photo frame 9700. For example, The photo frame 9700 has a display unit 9703 integrated into the housing 9701. Section 9703 is capable of displaying various images, such as those captured by a digital camera. By displaying the image data, it can function just like a regular photo frame.

[0234] The Digital Photo Frame 9700 includes an operating unit and external connection terminals (USB terminal, USB port). A structure that includes terminals that can connect to various cables such as B cables, a recording medium insertion section, etc. These components may be incorporated on the same surface as the display unit, but may also be on the sides or back. It is desirable to include it as it improves the design. For example, the recording medium of a digital photo frame. A memory device containing image data captured by a digital camera is inserted into the body insertion site. The system can capture data and display the captured image data on the display unit 9703.

[0235] Furthermore, the 9700 digital photo frame may be configured to transmit and receive information wirelessly. It is also possible to configure the system to acquire and display desired image data wirelessly.

[0236] Figure 25(A) shows a portable gaming machine, which consists of two casings, casing 9881 and casing 9891. It is connected by a connecting part 9893 so that it can be opened and closed. The housing 9881 has a display unit The 9882 is incorporated, and the display unit 9883 is incorporated into the housing 9891. The portable gaming machine shown in 25(A) also includes a speaker section 9884 and a recording medium insertion section 988 6. LED lamp 9890, input means (operation key 9885, connection terminal 9887, sensor 9 888 (force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, Chemical substances, sound, time, hardness, electric field, electric current, voltage, power, radiation, flow rate, humidity, gradient, vibration Equipped with a function to measure motion, odor, or infrared radiation, a microphone (9889), etc. Of course, the configuration of portable gaming machines is not limited to those described above, and at least the present invention Any configuration that includes a semiconductor device according to one embodiment is acceptable, and other auxiliary equipment may be provided as appropriate. It can be made to be completed. The portable gaming machine shown in Figure 25(A) is recorded on a recording medium. Functions include reading programs or data and displaying them on the display unit, and wireless communication with other portable gaming machines. It has the function of communicating and sharing information. Furthermore, the portable gaming machine shown in Figure 25(A) has this function. The functions are not limited to these, and it can have a variety of functions.

[0237] Figure 25(B) shows an example of a large-scale gaming machine, the slot machine 9900. The machine 9900 has a display unit 9903 integrated into the casing 9901. The Machine 9900 also features other operating mechanisms such as a start lever and stop switch, and coins. It is equipped with an input slot, speaker, etc. Of course, the configuration of the slot machine 9900 is as described above. The invention is not limited to any particular type of semiconductor device, but any configuration comprising a semiconductor device according to at least one aspect of the present invention is acceptable. Furthermore, the configuration may include other auxiliary equipment as appropriate.

[0238] Figure 26 shows an example of a mobile phone 1000. The mobile phone 1000 has a housing 100 In addition to the display unit 1002 incorporated into 1, there are also operation buttons 1003, an external connection port 1004, It is equipped with speaker 1005, microphone 1006, etc.

[0239] The mobile phone 1000 shown in Figure 26 allows information to be entered by touching the display unit 1002 with a finger or the like. It can be powered. Also, operations such as making a phone call or sending an email are performed on the display unit 100. This can be done by touching step 2 with your finger or other object.

[0240] The display unit 1002 has three main modes. The first is a display that primarily displays images. The first mode is display mode, the second is input mode which is mainly for inputting information such as characters. The third is display mode. This is a display + input mode, which is a combination of two modes: display mode and input mode.

[0241] For example, when making a phone call or composing an email, the display unit 1002 is used for text input. In this case, the primary text input mode should be used, and you should perform the input operation for the 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. It seems so.

[0242] Furthermore, the mobile phone 1000 contains sensors that detect tilt, such as a gyroscope and an accelerometer. By providing a detection device, the orientation (vertical or horizontal) of the mobile phone 1000 can be determined, and the display The display on the display unit 1002 can be automatically switched.

[0243] Furthermore, the screen mode can be switched by touching the display unit 1002 or by operating the housing 1001. This is done by operating button 1003. Also, the type of image displayed on display unit 1002 Therefore, it is also possible to switch between them. For example, the image signal displayed on the display unit is a video signal. Switch to display mode if it's data, or to input mode if it's text data.

[0244] Furthermore, in input mode, the signal detected by the optical sensor of the display unit 1002 is detected and displayed If there is no input via touch operation on unit 1002 for a certain period of time, the screen mode will be changed to input mode. You may also control the system to switch from that display mode to a different mode.

[0245] The display unit 1002 can also function as an image sensor. For example, the display unit 10 By touching the palm or fingers to device 02, the device can capture palm prints, fingerprints, etc., to perform identity verification. It can also be used. In addition, the display unit has a backlight that emits near-infrared light or a sensor that emits near-infrared light. Using a light source designed for imaging, it is also possible to image finger veins, palmar veins, and other veins.

[0246] The protection circuit mounted in the electronic device of this embodiment reduces the number of contact holes for connection. In addition to reducing the occupied area, the second oxide has higher electrical conductivity than the first oxide semiconductor layer. The oxide semiconductor layer is placed between the first oxide semiconductor layer and the wiring layer, resulting in high functionality and stable operation. The electronic device of this embodiment, which is equipped with such a protection circuit, is highly reliable.

[0247] This embodiment can be implemented in appropriate combination with the configurations described in other embodiments. That is the case. [Explanation of Symbols]

[0248] 10 circuit boards 11 Scan line input terminal 12 Signal line input terminals 13 scan lines 14 signal lines 16 Guard Station 17 Pixel section 18 pixels 19 Pixel Transistors 20 Holding capacity section 21 Pixel electrodes 22 Capacity lines 23 Common terminals 24 Protection circuit 25 Protection circuit 26 Protection circuit 27 Capacity bus lines 28 Common Wiring 29 Common Wiring 30 Nonlinear elements 30a Nonlinear element 30b Nonlinear element 31 Nonlinear elements 31a Nonlinear element 31b Nonlinear element 100 circuit boards 102 Gate Insulator 105 Conductive film 107 Interlayer insulating film 111 Shuttle bus 113 Oxide semiconductor layer 114 Oxide semiconductor layer 114a Oxide semiconductor layer 114b Oxide semiconductor layer 115a conductive layer 115b Conductive layer 117a wiring layer 117b Wiring layer 128 contact holes 131 Resist Mask 170a Nonlinear element 170b Nonlinear element 581 Thin-film transistor 585 Insulating layer 587 Electrode layer 588 Electrode layer 589 Spherical particles 590a black area 590b White area 594 Cavity 595 Filling material 650 Common Wiring 651 scan lines 730a Nonlinear element 730b Nonlinear element 730c nonlinear element 740a Nonlinear element 740b nonlinear element 740c nonlinear element 740d Nonlinear element 1000 mobile phones 1001 enclosure 1002 Display section 1003 Operation Buttons 1004 External connection port 1005 Speaker 1006 Mike 2600 TFT substrate 2601 Opposing substrate 2602 Sealant 2603 pixel section 2604 display elements 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 2631 Poster 2632 In-car advertisement 2700 eBooks 2701 enclosure 2703 Casing 2705 ​​Display section 2707 Display section 2711 Shaft 2721 Power supply 2723 Operation Keys 2725 Speaker 4001 circuit board 4002 pixel section 4003 Signal Line Drive Circuit 4004 Scan Line Drive Circuit 4005 Sealant 4006 circuit 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 Insulating layer 4021 Insulating layer 4030 Pixel electrode layer 4031 Counter electrode layer 4032 Insulating layer 4501 circuit board 4502 pixel section 4503a Signal Line Drive Circuit 4504a Scan line drive circuit 4505 Sealant 4506 circuit 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 circuit boards 5301 pixel section 5302 Scan line drive circuit 5303 Signal Line Drive Circuit 5400 circuit boards 5401 pixel section 5402 Scan Line Drive Circuit 5403 Signal Line Drive Circuit 5404 Scan Line Drive Circuit 5501 Wiring 5502 Wiring 5503 Wiring 5504 Wiring 5505 Wiring 5506 Wiring 5543 nodes 5544 nodes 5571 Thin-film transistor 5572 Thin-film transistor 5573 Thin-film transistor 5574 Thin-film transistor 5575 Thin-film transistor 5576 Thin-film transistor 5577 Thin-film transistor 5578 Thin-film transistor 5601 Driver IC 5602 switch group 5603a Thin-film transistor 5603b Thin-film transistor 5603c Thin-Film Transistor 5611 Wiring 5612 Wiring 5613 Wiring 5621 Wiring 5701 Flip-flop 5703a Timing 5703b Timing 5703c Timing 5711 Wiring 5712 Wiring 5713 Wiring 5714 Wiring 5715 Wiring 5716 Wiring 5717 Wiring 5721 Signal 5803a Timing 5803b Timing 5803c Timing 5821 Signal 6400 pixels 6401 Switching Transistor 6402 drive transistor 6403 Capacitive 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 Emitting layer 7005 Anode 7011 Drive TFT 7012 Light-emitting element 7013 Cathode 7014 Emitting layer 7015 Anode 7016 Shielding membrane 7017 Conductive film 7021 Drive TFT 7022 Light-emitting element 7023 Cathode 7024 Emitting layer 7025 Anode 7027 Conductive film 9600 Television equipment 9601 enclosure 9603 Display section 9605 Stand 9607 Display section 9609 Operation Keys 9610 Remote Control Unit 9700 Digital Photo Frame 9701 enclosure 9703 Display section 9881 cabinet 9882 Display section 9883 Display section 9884 Speaker section 9885 Operation Keys 9886 Recording medium insertion section 9887 Connection terminal 9888 Sensor 9889 Microphone 9890 LED Lamp 9891 cabinet 9893 Connection section 9900 slot machines 9901 cabinet 9903 Display section

Claims

1. It has a first transistor and a second transistor, The gate electrode of the first transistor is electrically connected to one of the source electrode and drain electrode of the first transistor, and to one of the source electrode and drain electrode of the second transistor, respectively. The gate electrode of the second transistor is electrically connected to the other of the source electrode and drain electrode of the second transistor, and to the other of the source electrode and drain electrode of the first transistor, respectively, in a semiconductor device. A first conductive layer having the function of a gate electrode of the first transistor, A second conductive layer having the function of a gate electrode of the second transistor, A first insulating film having a region located on the first conductive layer and a region located on the second conductive layer, A first oxide semiconductor layer having a region that overlaps with the first conductive layer via the first insulating film, A second oxide semiconductor layer having a region that overlaps with the second conductive layer via the first insulating film, A third conductive layer having a region located on the first oxide semiconductor layer and a region located on the second oxide semiconductor layer, and having the function of one of the source electrode and drain electrode of the first transistor and the function of one of the source electrode and drain electrode of the second transistor, A fourth conductive layer having a region located on the first oxide semiconductor layer and a region located on the second oxide semiconductor layer, and having the function of the other of the source electrode and drain electrode of the first transistor and the function of the other of the source electrode and drain electrode of the second transistor, The invention comprises a second insulating film having a region in contact with the upper surface of the first oxide semiconductor layer, a region in contact with the upper surface of the second oxide semiconductor layer, a region in contact with the upper surface of the third conductive layer, and a region in contact with the upper surface of the fourth conductive layer. In a plan view, the first oxide semiconductor layer and the second oxide semiconductor layer are arranged separately from each other. The second conductive layer has a region that contacts the third conductive layer at the first opening of the first insulating film, The fourth conductive layer has a region that contacts the first conductive layer at the second opening of the first insulating film, In a plan view, the third conductive layer has a region that intersects with the first conductive layer. A semiconductor device in which, in a plan view, the third conductive layer has a region that extends in a direction that intersects the channel length direction of the first transistor and the channel length direction of the second transistor.

2. A display device having a circuit section and a pixel section on a substrate, The circuit section includes a first transistor and a second transistor, A first conductive layer having the function of a gate electrode of the first transistor, A second conductive layer having the function of a gate electrode of the second transistor, A first insulating film having a region located on the first conductive layer and a region located on the second conductive layer, A first oxide semiconductor layer having a region that overlaps with the first conductive layer via the first insulating film, A second oxide semiconductor layer having a region that overlaps with the second conductive layer via the first insulating film, A third conductive layer having a region located on the first oxide semiconductor layer and a region located on the second oxide semiconductor layer, and having the function of one of the source electrode and drain electrode of the first transistor and the function of one of the source electrode and drain electrode of the second transistor, A fourth conductive layer having a region located on the first oxide semiconductor layer and a region located on the second oxide semiconductor layer, and having the function of the other of the source electrode and drain electrode of the first transistor and the function of the other of the source electrode and drain electrode of the second transistor, The invention comprises a second insulating film having a region in contact with the upper surface of the first oxide semiconductor layer, a region in contact with the upper surface of the second oxide semiconductor layer, a region in contact with the upper surface of the third conductive layer, and a region in contact with the upper surface of the fourth conductive layer. In a plan view, the first oxide semiconductor layer and the second oxide semiconductor layer are arranged separately from each other. The second conductive layer has a region that contacts the third conductive layer at the first opening of the first insulating film, The fourth conductive layer has a region that contacts the first conductive layer at the second opening of the first insulating film, In a plan view, the third conductive layer has a region that intersects with the first conductive layer. In a plan view, the third conductive layer has a region that extends in a direction intersecting the channel length direction of the first transistor and intersecting the channel length direction of the second transistor. The pixel portion has a plurality of pixels arranged in a matrix, At least one of the plurality of pixels has a third transistor having a third oxide semiconductor layer, and a fifth conductive layer electrically connected to the third transistor and functioning as a pixel electrode. A display device wherein the fifth conductive layer has a region located above the second insulating film.

Images