Display device

Abstract

To provide a display device that is easy to design, and has a freedom degree of design improved.SOLUTION: A display device has a pixel circuit and a drive circuit which are provided in a display unit. The drive circuit has a plurality of pulse output circuits. The pulse output circuit has a function driving a gate line. The pixel circuit is electrically connected to the gate line. The pulse output circuit has a first transistor. The pixel circuit has a second transistor. A layer where the second transistor is provided is an upper layer of a layer where the first transistor is provided, and the display device is configured such that the first transistor and second transistor have an overlapping region.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an article, a method, or a manufacturing method. The present invention relates to a method, manufacture, or composition of matter. One embodiment of the present invention is a semiconductor device, a light-emitting device, a display device, an electronic device, a lighting device, or any of these devices. The present invention relates to a driving method thereof or a manufacturing method thereof, and in particular to a display device (display panel). Alternatively, the present invention relates to an electronic device, a light-emitting device, a lighting device, or a manufacturing method thereof that includes a display device. Regarding.

[0002] In this specification and the like, a semiconductor device is a device that can function by utilizing semiconductor characteristics. This refers to devices in general. Transistors, semiconductor circuits, arithmetic units, memory devices, etc. are all types of semiconductor devices. The light-emitting device, the display device, the electronic device, the lighting device, and the electronic device are also semiconductor devices. The following may be present: [Background technology]

[0003] Liquid crystal display devices used in electronic devices, EL (Electroluminescence ce) Display devices such as display devices are becoming increasingly narrow-framed in order to reduce size and improve design freedom. To achieve a narrower frame, it is necessary to integrate the pixel circuit and the driver circuit on the same substrate. It is effective to provide part or all of the above.

[0004] The driving circuit is a CMOS (Complementary Metal Oxide Generally, it is composed of a single-polarity transistor. For example, in Patent Document 1, a circuit such as a shift register is used. A technique is disclosed in which the transistors are configured to have the same conductivity type.

[0005] In order to narrow the frame, the area where the pixels are provided (pixel area) is provided with a shift register, etc. For example, in Patent Document 2, a gate driver is provided in the pixel region. The present invention discloses a configuration in which a lever is provided to improve design freedom. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2014-211621 A [Patent Document 2] WO 2014 / 69529 Summary of the Invention [Problem to be solved by the invention]

[0007] In the configuration described in Patent Document 2, gate drivers are distributed and arranged within the pixel region. Therefore, the pixel circuit in which the transistors constituting the gate driver are arranged and the gate In this case, there are pixel circuits in which the transistors that constitute the driver are not arranged. The pixel circuit in which the transistors that make up the gate driver are arranged is The pixel area is larger than that of a pixel circuit that does not have a transistor that forms a high-speed pixel. There is a problem that it becomes difficult to achieve precision.

[0008] Another problem is that the pixel transistors that make up the gate driver are The circuit is mixed with a pixel circuit that does not have a transistor that configures a gate driver. In this case, two types of pixel circuits exist, which complicates the circuit design. Similarly, there is a problem with the wiring that connects the transistors that make up the gate driver. The wires also have different wiring relationships, which complicates the circuit design and causes problems. .

[0009] An object of one embodiment of the present invention is to provide a display device with a narrow frame. One of the objectives is to provide a display device that improves the freedom of design. It is an object of the present invention to provide a display device having a pixel circuit capable of improving a display brightness. Another object is to provide a display device that can avoid the complication of circuit design. Another object of the present invention is to provide a display device with low power consumption. One of the objects of the present invention is to provide an electronic device having the above-mentioned display device (display panel). One of the objectives is to provide a new electronic device. It shall be one of the following.

[0010] The description of these problems does not preclude the existence of other problems. It is not necessary to solve all of these problems. Problems other than those mentioned above are not necessarily solved. It will become clear from the description of the specification, etc., and problems other than those mentioned above will not be identified from the description of the specification, etc. It is possible to extract [Means for solving the problem]

[0011] One embodiment of the present invention is a display portion including a layer having a transistor which constitutes a pixel circuit, A layer having a transistor that constitutes a driver circuit is laminated on the upper layer. The transistors that make up the gate driver, which is the driving circuit, are placed on the lower layer. By placing the gate driver in the frame area under the display area, This allows for greater freedom in design, such as narrowing the frame. By arranging different transistors, pixel circuits with the same circuit layout can be designed repeatedly. Therefore, it is possible to prevent the circuit design from becoming complicated.

[0012] One embodiment of the present invention includes a pixel circuit and a driver circuit provided in a display portion, The pixel includes a plurality of pulse output circuits, each of which has a function of driving a gate line. The circuit is electrically connected to the gate line, and the pulse output circuit has a first transistor; The pixel circuit has a second transistor, and the layer in which the second transistor is provided is a first The upper layer is a layer on which the transistors are provided. The first transistor and the second transistor are A display device having an overlapping area.

[0013] One embodiment of the present invention includes a pixel circuit and a driver circuit provided in a display portion, The pixel includes a plurality of pulse output circuits, each of which has a function of driving a gate line. The circuit is electrically connected to the gate line, and the pulse output circuit has a first transistor; The pixel circuit has a second transistor, and the layer in which the second transistor is provided is a first The upper layer is a layer on which the transistors are provided. The first transistor and the second transistor are The conductive layer having an overlapping region and functioning as a gate line is provided with a first transistor. The display device is provided on the same layer as the light emitting layer.

[0014] In one embodiment of the present invention, the first transistor and the second transistor are unipolar. Certain display devices are preferred.

[0015] In one embodiment of the present invention, the channel shapes of the first transistor and the second transistor are The display device preferably has a metal oxide-containing region.

[0016] In one aspect of the present invention, the pixel circuit has a first display element, and the first display element is A display device having a function of emitting visible light or a function of transmitting visible light is preferred.

[0017] In one embodiment of the present invention, the pixel circuit further comprises a second display element. In the present embodiment, the display device is preferably one having a function of reflecting visible light.

[0018] In one embodiment of the present invention, the pixel circuit further comprises a third transistor. In the display device, the first transistor is preferably provided in the same layer as the first transistor. stomach.

[0019] In this specification, a connector, such as an FPC (Flexible Printed Circuit) Printed Circuit) or TCP (Tape Carrier Pa A module with a printed wiring board at the end of the TCP. COG (Chip On Glass) method is applied to the substrate on which the module or display element is formed. Depending on the formula, a module on which an IC (integrated circuit) is directly mounted may also be included in the display device. Effect of the Invention

[0020] According to one embodiment of the present invention, a display device with a narrow frame can be provided. It is possible to provide a display device that improves the freedom of viewing or that improves the definition. It is possible to provide a display device having a pixel circuit that can achieve the above-mentioned display device. Alternatively, a display device with low power consumption can be provided. Alternatively, a novel display device can be provided. It is possible to provide an electronic device having a display panel. Alternatively, a novel electronic device can be provided. It is possible.

[0021] The description of these effects does not preclude the existence of other effects. An embodiment does not necessarily have to have all of these effects. The above will become apparent from the description in the specification, drawings, claims, etc. It is possible to extract other effects from the descriptions in the claims, etc. [Brief description of the drawings]

[0022] [Figure 1] 1A and 1B are diagrams illustrating a display device. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. 2 is a circuit diagram illustrating a pixel circuit. [Figure 6] 1A to 1C are a diagram illustrating a driver circuit, a circuit diagram, and a timing chart. [Figure 7] FIG. 4 is a circuit diagram illustrating a display unit. [Figure 8] FIG. 4 is a circuit diagram illustrating a display unit. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. [Figure 12] FIG. [Figure 13] FIG. 1 illustrates a structure of a display device. [Figure 14]FIG. [Figure 15] 1A and 1B are a block diagram illustrating a display device and a diagram illustrating electrodes included in a pixel. [Figure 16] FIG. 2 is a diagram illustrating a pixel circuit. [Figure 17] 1A and 1B are a diagram illustrating a pixel circuit and a top view of a pixel. [Figure 18] FIG. 1 illustrates a structure of a display device. [Figure 19] FIG. 1 is a cross-sectional view illustrating a structure of a display device. [Figure 20] 1A to 1C are diagrams illustrating electronic devices. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The embodiment will be described in detail with reference to the drawings. However, the present invention is not limited to the following description. The present invention is not limited to the above embodiment, and various modifications and variations in form and detail may be made without departing from the spirit and scope of the present invention. It will be readily understood by those skilled in the art that the present invention can be modified in various ways. It should not be construed as being limited to the description of the embodiments.

[0024] In the configuration of the invention described below, the same parts or parts having similar functions The same reference numerals are used in common between different drawings, and the repeated explanations are omitted. When referring to similar functions, the hatch pattern may be the same and no particular reference number may be used.

[0025] In each figure described in this specification, the size, layer thickness, or area of ​​each component is indicated by the following formula: The figures may be exaggerated for clarity and are not necessarily limited to scale. stomach.

[0026] In this specification, ordinal numbers such as "first" and "second" are used to avoid confusion of components. The numbers are added for the purpose of convenience and are not intended to be limiting.

[0027] (Embodiment 1) A display device according to one embodiment of the present invention has a transistor which constitutes a pixel circuit in a display portion. A layer having a gate insulating film and a layer having a transistor constituting a driver circuit are stacked. The transistors that make up the pixel circuit are arranged, and the gate driver, which is the driving circuit, is arranged on the lower layer. The gate driver for the frame is placed below the display. This allows for greater freedom in design, such as narrowing the frame. By arranging the transistors that make up the pixel circuits, pixel circuits with the same circuit layout can be repeated. Since the circuit can be designed with only one input, it is possible to avoid the circuit design from becoming complicated.

[0028] <Example of display device configuration> The configuration of the display device will be described with reference to the drawings.

[0029] FIG. 1A is a diagram for explaining the configuration of a display device. The display device 11 includes a driving circuit The display unit 92 includes a plurality of pixel circuits 94 and a display The pixel circuit 94 and the display element may be collectively referred to as a pixel.

[0030] The driving circuit 91 has a plurality of pulse output circuits. The driving circuit 91 receives a gate clock signal. A gate start pulse GCK and a gate start pulse GSP are input from a driving circuit 93. 1 has a function as a gate line driver circuit. In FIG. 1(A), a plurality of pulse output circuits As an example of the pulse output circuit 91, pulse output circuits 91_1 to 91_4 are illustrated. Gate lines GL_1 to GL_4 function as shift registers. A scanning signal is output to the pixel circuit 94 via the

[0031] The pulse output circuits 91_1 to 91_4 of the drive circuit 91 each include a plurality of transistors. The transistors included in the driver circuit 91 are used to form a single circuit such as a shift register. It is composed of polarity transistors.

[0032] The driver circuit 93 is an integrated circuit having functions as a source line driver circuit and a display controller. The driving circuit 93 outputs a gate clock signal GCK and a gate start pulse GSP to the driving circuit 91, and image data D V The pixel circuit 94 It has the function of outputting to.

[0033] The pixel circuit 94 controls the voltage or current applied to the display element according to the voltage of the image data. The display element is a circuit that displays voltage or current such as a liquid crystal element or an EL display element. It is an element that can control the gradation according to the current.

[0034] The pixel circuit 94 has a plurality of transistors. Like circuits such as photoresistors, they are made up of transistors of the same conductivity type.

[0035] FIG. 1B is a diagram for explaining the layered structure of the display device 11 of FIG. In the device 11, a layer 101 having transistors constituting a driving circuit 91 and a pixel circuit 94 A layer 102 having a transistor constituting the display element and a layer 103 having a display element are stacked. establish.

[0036] FIG. 1C shows a configuration of the display device 11 shown in FIG. 1A, with the laminated structure shown in FIG. 1B. In FIG. 1(C), the x-direction, the y-direction, and the z-direction are shown. The x direction corresponds to the gate lines GL_1 to GL_4 as shown in FIG. The y direction is parallel to the source line. The z direction is parallel to the As shown, this is a direction perpendicular to the plane defined by the x and y directions.

[0037] In FIG. 1C, a layer 101 having a transistor constituting a driver circuit 91 and a pixel circuit Layer 101 includes a transistor for forming a pulse output. The layer 102 includes the pixel circuits 94 and the gate lines GL_ 1 to GL_4. In FIG. 1C, the driver circuit 93 is illustrated, but the layers 101 and It is preferable that the layer is provided on a layer different from layer 102.

[0038] As described with reference to FIGS. 1A to 1C, in the display device 11 according to one embodiment of the present invention, a pixel circuit In the display section 92 having the pixel circuit 94, the layer 10 having the transistors constituting the pixel circuit 94 2 and a transistor constituting a driving circuit 91 having pulse output circuits 91_1 to 91_4. The layer 101 having the photoresist is laminated to the frame portion. A driving circuit 91 functioning as a gate driver for the display unit 92 is disposed under the display unit 92. This allows for greater freedom in design, such as narrowing the frame. By arranging transistors that form the circuit 94, pixel circuits 94 with the same circuit arrangement are repeated. Since the circuit can be designed by the above, it is possible to avoid the circuit design from becoming complicated.

[0039] In addition, in FIG. 1(A) and FIG. 1(C), the pulse output circuit of the driving circuit 91 is Although the pulse output circuits 91_1 to 91_4 are shown, other configurations may be used.

[0040] For example, as shown in FIG. 2A, a display unit 92 includes a driving circuit 91A. The driving circuit 91A includes pulse output circuits 91_1 to The driving circuit 91A has a gate clock signal GCK_ A, GCK_B, gate start pulse GSP, and potential VSS are given. Pulse output circuit The output signals of the circuits 91_1 to 91_n are respectively connected to the gate lines GL_1 to GL_n. The output signals of the pulse output circuits 91_n+1 and 91_n+2 are This signal serves as a reset signal for the pulse output circuit of the stage.

[0041] Alternatively, for example, as shown in FIG. 2B, a display unit 92 includes a driving circuit 91A, a driving A configuration may be adopted in which the driving circuit 91B has a different number of pulse output circuits from the circuit 91A. The driving circuits 91A and 91B are stacked on the pixel circuits (not shown) in the display section 92. can be done.

[0042] The driving circuit 91A receives gate clock signals GCK_A, GCK_B, and a gate start pulse The pulse output circuits 91_1 to 91_n are supplied with a potential GSP and a potential VSS. The pulses are output to the gate lines GLA_1 to GLA_n as scanning signals. The output signals of the circuits 91_n+1 and 91_n+2 reset the pulse output circuit of the preceding stage. This serves as a signal to

[0043] The driving circuit 91B includes pulse output circuits 91_1 to 91_s+2 (s is a natural number). The driving circuit 91B receives the gate clock signals GCK_A, GCK_B, the gate start pulse The pulse output circuits 91_1 to 91_s are supplied with a potential GSP and a potential VSS. The pulses are output to the gate lines GLB_1 to GLB_s as scanning signals. The output signals of the circuits 91_s+1 and 91_s+2 reset the pulse output circuit in the preceding stage. This serves as a signal to

[0044] FIG. 3 shows a configuration similar to that of FIG. 1C, in which the driving circuits 91A and 91B shown in FIG. 2B are included. 1B is reflected in the configuration of a display unit 92 shown in FIG.

[0045] In FIG. 3, the transistors and the pulse output circuits 91_1 to 91_n+2 are A layer 101 having transistors included in the input circuits 91_1 to 91_s+2, and a pixel A layer 102 having transistors that constitute the circuit 94 is shown. 1(C) is omitted.

[0046] As shown in FIG. 3, the pulses of the driving circuits 91A and 91B shown in FIG. By varying the number of output circuits, the number of pixels in the y direction can be varied. This allows for greater freedom in the shape of the display unit.

[0047] In the configuration shown in FIG. 1C, the gate lines GL_1 to GL_4 are provided on the layer 102. However, it may be arranged in layer 101 as shown in FIG. 4(A). In the configuration shown in FIG. 1C, the pixel circuit 94 is provided in the layer 102. As shown in FIG. 4B, a part of the pixel circuit, circuit 94B, is arranged on layer 101. This is also fine.

[0048] As described above, in the display device according to one embodiment of the present invention, a pixel circuit is formed in a display portion. A layer having a transistor constituting a driver circuit and a layer having a transistor constituting a driver circuit are stacked. The upper layer is provided with transistors that constitute the pixel circuits, and the lower layer is provided with the driver circuits. The transistors that make up the gate driver are placed. The gate driver is placed in the frame area. By placing it under the display unit, it is possible to increase the degree of freedom in design, such as by making the frame narrower. In addition, by arranging the transistors that form the pixel circuits on the upper layer of the display, pixels with the same circuit layout can be Since the circuit can be designed by repeating the circuit, it is possible to avoid the circuit design becoming complicated. do.

[0049] <Pixel circuit configuration example> 5A to 5C show an example of a pixel circuit. The pixel circuit is illustrated together with the display element.

[0050] FIG. 5A is an example of a pixel circuit in which the display element is a liquid crystal element. A transistor M1, a capacitance element C1, a liquid crystal element LC, a common electrode COM, a source line SL, and The gate lines GL are also shown.

[0051] FIG. 5B is an example of a pixel circuit in which a display element is a light-emitting element. Transistor M1, transistor M2, capacitance element C1, light-emitting element EL, anode line anod e, the cathode line, the source line SL, and the gate line GL are shown.

[0052] FIG. 5C is an example of a pixel circuit that uses a display element as a light-emitting element, which is different from FIG. 5B. In FIG. 5C, a transistor M1, a transistor M2, a transistor M3, a capacitance element C1, light-emitting element EL, anode line anode, cathode line cathode, monitor line ML, source lines SL, and gate lines GL are shown.

[0053] <Drive circuit configuration example> 6A to 6C are examples of a driving circuit, a pulse output circuit, and a timing chart. is illustrated.

[0054] FIG. 6A shows an example of a shift register included in a driver circuit. The gate output circuits SR_1 to SR_n+2, wiring for supplying the gate clock signal GCK_A, The wiring that supplies the gate clock signal GCK_B and the wiring that supplies the gate start pulse GSP The wiring between the pulse output circuits SR_1 and SR_2 is connected to the gate line GL. The output signals of the pulse output circuits SR_n+1 and SR_n+2 are connected to the This signal is used to reset the output circuit.

[0055] FIG. 6B is applicable to the pulse output circuits SR_1 to SR_n+2 shown in FIG. FIG. 6B shows an example of a circuit configuration of a pulse output circuit SR that can be used. The transistors M11 to M14 and the capacitor C11 are included. The signals and voltages given to each transistor are the gate clock signal GCK_A, the gate Clock signal GCK_B, output signal GL, gate start pulse GSP (or the previous pulse The output signal of the next pulse output circuit SR, Former GL, ext GL and voltage VSS are illustrated. Also, in FIG. 6B, transistor M11, The node connected to M12, M13 and the capacitive element C11 is illustrated as netA. .

[0056] FIG. 6C is a timing chart for explaining the operation of the pulse output circuit SR shown in FIG. 6B. At time T1 in FIG. 6(C), GCK_A is at a low level and GCK_B is at high level, and at this time GSP is set to high level, increasing the voltage of netA. Next, at time T2, since GSP is at a low level, netA becomes floating. At time T2, GCK_A is at high level and GCK_B is at low level, so the floating The voltage of netA, which is the input, rises due to the capacitive coupling of the capacitive element C11. The transistor M13 is turned on, and GL goes high. At time T3, Nex When GL goes high, netA goes low and GCK_B goes high. When this happens, GL goes low.

[0057] <Example of stacking of pixel circuits and driving circuits> FIG. 7 shows a structure in which the pixel circuit of FIG. 5(B) and the pulse output circuit of FIG. 6(B) are stacked. The circuit symbols are used to illustrate the configuration example. In FIG. 7, the x-axis direction is the same as in FIG. 1(C). In FIG. 7, the layer 10 described in FIG. 1(B) is A pulse output circuit, a pixel circuit, and a light-emitting element which is a display element are provided corresponding to layers 1 to 103. Illustrated.

[0058] The pixel circuits of the layer 102 provided above the layer 101 are arranged in the y direction as shown in FIG. That is, the gate lines GL are spaced apart (G Pitch), and the x-direction, i.e., the source line The wiring pitch (S pitch) of the layer 101 is SL. As shown in FIG. 7, the pitch (G Pitch) of the gate lines GL is set in the y direction. However, there is no restriction in the x direction. Therefore, the driver circuit including the pulse output circuit is arranged In addition, the pixel circuits provided in the layer 102 can be arranged in a The pixel circuits can also have the same circuit configuration, so there is no need to mix different types of circuit configurations. This makes it easier to design the circuit compared to the conventional method.

[0059] FIG. 8 shows a case where the pixel circuit of FIG. 5(C) and the pulse output circuit of FIG. 6(B) are stacked. The configuration example is illustrated using circuit symbols. In FIG. 8, as in FIG. 7, 8, the y direction and the z direction are illustrated. In FIG. 8, similarly to FIG. 7, the same as in FIG. 1(B) is illustrated. Corresponding to the layers 101 to 103, a pulse output circuit, a pixel circuit, and a display element are 1 illustrates a light emitting element.

[0060] The difference between the diagram in FIG. 8 and the diagram in FIG. 7 is that the transistor M3 and the The point is that the monitor line ML is provided in the layer 101. As described above, in the configuration of one embodiment of the present invention, The pulse output circuit of the layer 101 is arranged in the y direction, that is, the arrangement of the gate lines GL, as shown in FIG. The line spacing (G Pitch) is not limited in the x direction. It is also possible to provide circuits other than the input circuit, for example a part of the pixel circuit. The number of transistors can be reduced, which reduces the area of ​​the pixel circuit and allows for higher resolution. It may be a display device.

[0061] FIG. 9(A) shows a top view of the pulse output circuit of FIG. 6(B). FIG. 9(B) shows a top view of the pulse output circuit of FIG. 9(A) and (B) show top views of the pixel circuit shown in FIG. 5(B) and FIG. The configurations corresponding to those in FIG. 9(A) and (B) are illustrated with the same reference numerals. In (B), the x- and y-directions are shown which are labelled in FIG. 1(C).

[0062] In FIGS. 9A and 9B, a conductive layer 401 is provided in the same layer as the gate electrode of a transistor. The conductive layer 402 represents a source electrode or a drain electrode of a transistor. 9A and 9B, the semiconductor layer 40 is a layer provided in the same layer as the electrode. 3 represents a layer provided in the same layer as the semiconductor layer of the transistor. ), an opening 404 represents an opening for connecting the conductive layer 401 and the conductive layer 402. In FIG. 9B, the opening 405 is formed between the conductive layer 402 and the upper layer 103. It represents an opening for connecting to a certain light-emitting element EL.

[0063] In FIG. 10, a layer 1 having a top view of the pulse output circuit of FIG. 6(B) shown in FIG. 9B, a layer 102 having a top view of the pixel circuit of FIG. 5B is laid on the substrate 101. In FIG. 10, the configurations corresponding to those in FIG. 9(A) and (B) are denoted by the same reference numerals. In FIG. 10, the x-direction, y-direction, and z-direction indicated in FIG. 1(C) are also shown. The directions are illustrated.

[0064] As shown in FIG. 10, the pixel circuit in layer 102 includes openings 406A and 406B. At 406B, the gate line GL of the layer 101 is connected. Since the pixel circuit having the same circuit design, the wiring relationship is not complicated. As shown in FIG. 10, the pixel circuit in layer 102 can be designed without any problem. Each element such as a transistor included in the pulse output circuit in the layer 101 is a transistor included in the pulse output circuit in the layer 102. The capacitor and other elements are provided on top of each other.

[0065] <Example of the configuration of transistors provided in different layers> FIG. 11 shows transistors and pixel circuits included in a driver circuit 91, which are provided in different layers. FIG. 1 is a top view illustrating a stacked structure of a transistor in the semiconductor device according to the first embodiment. 2(A) is a cross-sectional view taken along the line Y1-Y2 in FIG. 11, and FIG. 12(B) is a cross-sectional view taken along the line X1-X2 in FIG. In order to clarify the structure, some insulating layers are omitted from the drawings or are not labeled with reference numerals. is.

[0066] The transistors included in the driver circuit 91 provided in the layer 101 are the transistor 61. The transistor 61 includes a gate electrode 63, a gate insulating film 69, a semiconductor The transistor 71a has a gate electrode 62, a source electrode 64, and a drain electrode 65. Electrode 73a, gate insulating film 79a, semiconductor layer 72a, source electrode 75a, drain electrode 7 Has 4a.

[0067] The pixel circuit 94 provided in the layer 102 includes a transistor The transistor 71b includes a gate electrode 73b, a gate insulating film 79b, It has a semiconductor layer 72b, a source electrode 75b, and a drain electrode 74b.

[0068] Although the transistors 71a and 71b are illustrated as being the same size, they are different. The transistor may have a different size.

[0069] The transistor is not limited to a bottom gate type, but may be a top gate type. A dual gate type in which gate electrodes are arranged above and below the conductor layer may be used. In the case of the transistor, the same potential may be applied to both gate electrodes. Different potentials, such as a potential for controlling the voltage or a potential for increasing the on-current, are used. The configuration may be such that the

[0070] The planarization film 25 provided between the transistors 71a and 71b was omitted. It may be a configuration.

[0071] The gate electrode 73a of the transistor 71a is connected to the gate electrode 61 of the transistor 61 at the connection 66. The drain electrode 65 is electrically connected to the gate electrode 73b of the transistor 71b. In FIG. 12B, the connection portion 66 is the same as the source electrode 75b and the drain electrode 74b. Although the structure having the conductive layer 77 that can be provided in one step is shown, the conductive layer 77 is not necessarily provided. It is also possible to adopt a configuration in which this is not necessary.

[0072] By using the above configuration, a display unit having a transistor constituting a pixel circuit can be A layer having a transistor included in a driver circuit and a layer having a transistor included in a driver circuit can be stacked. The upper layer is made up of transistors that make up the pixel circuits, and the lower layer is made up of gate drivers that drive the pixels. A transistor that constitutes a driver can be arranged. Since there is no restriction on the arrangement of the pixels, a display device with a narrow frame can be formed.

[0073] Semiconductor device such as a transistor used in a pixel circuit and a driver circuit of a display device For this purpose, it is preferable to use an oxide semiconductor using a metal oxide for the semiconductor layer. As an example of a semiconductor, there is CAC-OS (Cloud-Aligned Co-semiconductor) MPO-Oxide Semiconductor, etc. can be used. .

[0074] In particular, it is preferable to use an oxide semiconductor having a band gap larger than that of silicon. If a semiconductor material with a wider band gap and lower carrier density than silicon is used, Therefore, the current in the off state of the transistor can be reduced.

[0075] In addition, due to its low off-state current, the charge stored in the capacitance through the transistor can be released for a long period of time. By applying such a transistor to a pixel, It is also possible to stop the driving circuit while maintaining the grayscale of the image displayed on the display unit. As a result, it is possible to realize electronic devices with extremely reduced power consumption.

[0076] In addition, the pixels included in each display unit provided in the display device 11 and the transistors used in each drive circuit A polycrystalline semiconductor may be used for a semiconductor device such as a transistor. For example, polycrystalline silicon It is preferable to use polycrystalline silicon because it can be formed at a lower temperature than single crystal silicon. Moreover, it has higher field effect mobility and higher reliability than amorphous silicon. By applying such a polycrystalline semiconductor to a pixel, the aperture ratio of the pixel can be improved. Even in a case where there are a large number of pixels, the gate driver circuit and the source driver circuit are arranged in the same It is possible to form the components on a single substrate, and the number of components that make up the electronic device can be reduced. do.

[0077] This embodiment may be combined with other embodiments described in this specification, at least in part. It can be implemented in combination.

[0078] (Embodiment 2) In this embodiment, a display device that can be used in one embodiment of the present invention and a display device The driving method will be described.

[0079] A display device according to one embodiment of the present invention has a pixel provided with a first display element that reflects visible light. Alternatively, the display device may have a pixel provided with a second display element that emits visible light. Alternatively, the display device may have a pixel provided with a third display element that transmits visible light. Alternatively, a first display element and a second display element or a third display element may be provided. The pixel may have a pixel structure.

[0080] In this embodiment, a first display element that reflects visible light and a second display element that emits visible light are used. A display device having a display device and a display element is described.

[0081] The display device includes a first light reflected by a first display element and a second light emitted by a second display element. The device has a function to display an image by either one or both of the above. The device detects an amount of a first light reflected by a first display element and an amount of a second light emitted by a second display element. By controlling the amount of light of and , respectively, it has the function of expressing gradation.

[0082] The display device also expresses gradations by controlling the amount of reflected light from the first display element. The gradation is expressed by controlling the amount of light emitted from the first pixel and the second display element. It is preferable to have a configuration having a second pixel. The first pixel and the second pixel are, for example, A plurality of these are arranged in a matrix to form the display unit.

[0083] The first pixels and the second pixels are arranged in the display section in the same number and at the same pitch. As a result, an image displayed only by a plurality of first pixels, as described below, An image displayed only by the second pixels, and an image displayed by the first pixels and the second pixels Both pixel-displayed images can be displayed on the same display.

[0084] The first display element of the first pixel may be an element that reflects external light to display an image. Since such elements do not have a light source, the power consumption during display is extremely small. It becomes possible to do so.

[0085] The first display element can typically be a reflective liquid crystal element. The display element for the first display is a shutter-type MEMS (Micro Electro Mechanical Systems). In addition to the MEMS (mechanical system) element and the optical interference type MEMS element, electrophoretic method, electrowetting method, electronic liquid powder method, etc. An element to which the above is applied can be used.

[0086] The second display element of the second pixel has a light source and displays an image using light from the light source. In particular, a device that emits light from a light-emitting substance by applying an electric field can be used. It is preferable to use electroluminescent elements that can be extracted. The light emitted by the projector has high color reproducibility (wide color gamut) because its brightness and chromaticity are not affected by external light. It is possible to provide a high-contrast, i.e., vivid display.

[0087] The second display element is, for example, an OLED (Organic Light Emitting g Diode), LED(Light Emitting Diode), QLED( Quantum-dot Light Emitting Diode, semiconductor laser Alternatively, a self-luminous light-emitting element such as a display element The backlight is the light source, and the transparent element controls the amount of light transmitted from the backlight. A combination with a transmission type liquid crystal element may also be used.

[0088] The first pixel may be a sub-pixel that exhibits, for example, white (W) or red (R), green (G), or The pixel may have sub-pixels that emit three colors of light: red (A), green (B), and blue (B). Similarly, the second pixel may be a subpixel that exhibits, for example, white (W) or red (R), It is possible to configure the display device to have sub-pixels that emit three colors of light: green (G), blue (B), and blue (B). The sub-pixels of each of the first pixel and the second pixel can have four or more colors. The more types of sub-pixels there are, the more power consumption can be reduced and the better the color reproducibility can be. It can be done.

[0089] In one aspect of the present invention, a first mode displays an image at a first pixel, and a second mode displays an image at a second pixel. a second mode for displaying an image on the first pixel and a second pixel; and a third mode for displaying an image on the first pixel and the second pixel. can be switched.

[0090] The first mode is a mode in which an image is displayed using light reflected by a first display element. The first mode does not require a light source, so it is a driving mode with extremely low power consumption. For example, This is effective when the illuminance of the external light is sufficiently high and the external light is white light or light close to white light. The first mode is a display mode suitable for displaying text information such as books and documents. In addition, because it uses reflected light, it is possible to provide a display that is gentle on the eyes and reduces eye fatigue. This has the effect of

[0091] In the second mode, an image is displayed by utilizing light emitted by the second display element. Therefore, it is extremely vivid (high contrast and color) regardless of the illuminance or chromaticity of the external light. For example, when the illuminance of external light is extremely low, such as at night or in a dark room, This is effective when the display is very small. Also, when the outside light is dark, a bright display can be dazzling to the user. To prevent this, the second mode uses a lower brightness display. This not only reduces glare but also reduces power consumption. The second mode is suitable for displaying vivid images and smooth videos. This is the mode.

[0092] In the third mode, both the reflected light by the first display element and the emitted light by the second display element are Specifically, the light emitted by the first pixel and the light emitted by the second pixel are used to display the image. The light emitted by the first pixel and the light emitted by the adjacent second pixel are mixed to produce a single color. It provides a brighter display than the first mode, while consuming less power than the second mode. For example, under indoor lighting or in the early morning or early evening, when the illuminance of external light is relatively high, This is effective when the chromaticity of the external light is not white or when the reflected light and emitted light are By using mixed color light, it displays images that make you feel as if you are looking at a painting. It becomes possible to do so.

[0093] Hereinafter, a more specific example of one embodiment of the present invention will be described with reference to the drawings.

[0094] [Example of display device configuration] FIG. 13A illustrates a display device 11 according to one embodiment of the present invention. The display device includes a layer 102 having a transistor and a layer 101 having a transistor. The device 11 may have a photometry unit that acquires the illuminance of external light, etc. A pixel circuit together with a display element will be described as a pixel.

[0095] The layer 102 has a plurality of pixels 45 arranged in a matrix. The pixels 45 are a first The layer 101 includes a pixel 46 and a second pixel 47. The layer 101 includes pulse output circuits 91_1 to 91_ Has 4.

[0096] In FIG. 13A, a first pixel 46 and a second pixel 47 are red (R) and green (G), respectively. 1 shows an example in which the display device has display elements corresponding to three colors: blue (G), green (B), and blue (C).

[0097] The first pixel 46 has a display element 46R corresponding to red (R) and a display element 46R corresponding to green (G). Display elements 46R, 46G, and display element 46B corresponding to blue (B). 46B are display elements that utilize reflection of external light.

[0098] The second pixel 47 has a display element 47R corresponding to red (R) and a display element 47R corresponding to green (G). Display elements 47R, 47G, and display element 47B corresponding to blue (B). Each of 47B is a display element that utilizes light from a light source.

[0099] In addition, the layer 102 in which the pixel 45 is provided includes a transistor as shown in FIG. Alternatively, the layer 102 in which the pixels 45 are provided may be a layer 102a having the same structure as shown in FIG. As shown in FIG. 1C, a stack of multiple layers, including layers 102a and 102b, each having a transistor, is formed. It can be a layer.

[0100] In the case of FIG. 13C, one of the first pixel 46 and the second pixel 47 is provided in the layer 102a. In addition, the other of the first pixel 46 or the second pixel 47 may be provided on the layer 102b. At this time, the transistor (first transistor) of the first pixel 46 is a layer 10 2a, and the transistor (second transistor) included in the second pixel 47 The first transistor and the second transistor may be disposed on the layer 102b. By adopting such a structure, the occupied area of ​​the transistor can be reduced. This makes it easier to increase pixel density.

[0101] The above is a description of the configuration example of the display device.

[0102] [Pixel configuration example] Next, the pixel 45 will be described with reference to FIGS. 14(A), (B), and (C). 1A, 1B, and 1C are schematic diagrams showing examples of the configuration of a pixel 45.

[0103] The first pixel 46 has a display element 46R, a display element 46G, and a display element 46B. The element 46R reflects external light and outputs the red light included in the first gradation value input to the first pixel 46. The display element 46G emits red light R1 having a luminance according to the gradation value corresponding to the display surface. Similarly, the display element 46B also emits green light G1 or blue light B1 toward the display surface. Put out.

[0104] The second pixel 47 has a display element 47R, a display element 47G, and a display element 47B. The element 47R has a light source and emits red light included in the second gradation value input to the second pixel 47. The display element 47G emits red light R2 having a luminance according to the corresponding gradation value toward the display surface. Similarly, the display element 47B emits green light G2 or blue light B2 toward the display surface. do.

[0105] [Third mode] FIG. 14A shows a display element 46R, a display element 46G, and a display element 46B that reflect external light. The light-emitting display elements 47R, 47G, and 47B are all driven to display an image. 14A shows an example of an operation mode for displaying. As shown in FIG. 14A, the pixel 45 receives light R1 By mixing six lights, G1, B1, R2, G2, and B2, Light 55 of a predetermined color can be emitted toward the display surface.

[0106] At this time, the luminance of each of the display elements 47R, 47G, and 47B is For example, the display element 47R, the display element 47G, and the display element 4 The maximum brightness of the light that each of 7B can emit (also called maximum brightness) is 100%. When the display elements 47R, 47G, and 47B are in the third mode, The maximum brightness of the light emitted by each of them should be 5% to 50%, preferably 1% It is preferable to set the display to 60% or less. This allows the display to be performed with low power consumption. This makes the displayed image more pictorial and easier on the eyes.

[0107] [First mode] FIG. 14B shows a display element 46R, a display element 46G, and a display element 46B that reflect external light. As shown in FIG. 14B, the pixel 45 does not drive the second pixel 47 when, for example, the illuminance of external light is sufficiently high, By mixing only the light from the first pixel 46 (light R1, light G1, and light B1), In addition, light 55 of a specific color can be emitted toward the display surface. This allows for extremely low power consumption. This allows for efficient driving.

[0108] [Second mode] FIG. 14C shows a case where an image is displayed by driving the display elements 47R, 47G, and 47B. 14C shows an example of an operation mode for displaying. As shown in FIG. 14C, the pixel 45, for example, When the illuminance of external light is extremely low, the first pixel 46 is not driven and the second pixel 4 By mixing only the light from 7 (light R2, light G2, and light B2), a desired color can be obtained. It is also possible to emit light 55 toward the display surface. This allows for a vivid display. In addition, by lowering the brightness when the illuminance of external light is low, the glare felt by the user is reduced. At the same time, power consumption can be reduced.

[0109] In this case, it is preferable to increase the luminance of the display element that emits visible light more than in the third mode. For example, in the second mode, the display elements 47R, 47G, and 47B The maximum brightness of the light emitted by each of them shall be 100% of the maximum brightness, or 50% or more and 10 0% or less, preferably 60% to 100%. It can display vivid images even in bright places.

[0110] Here, the brightness of the light emitted by each of the display elements 47R, 47G, and 47B is The maximum value of the degree can be replaced by the dynamic range. In the second mode, the display elements 47R, 47G, and 47B are For example, the dynamic range of the display element 47R can be set narrower. The dynamic range of the third mode in the display element 47G or the display element 47B is The dynamic range of the input should be set to 5% or more and 50% or less, preferably 1% or more and 60% or less. It is possible.

[0111] The above is a description of an example of the configuration of the pixel 45.

[0112] This embodiment may be combined, at least in part, with other embodiments described in this specification. It can be implemented in combination.

[0113] (Embodiment 3) An example of a display panel that can be used in a display device according to one embodiment of the present invention will be described below. The display panel exemplified below has both a reflective liquid crystal element and a light-emitting element, and The display panel is capable of displaying in both transmissive and reflective modes.

[0114] [Configuration example] FIG. 15A is a block diagram showing an example of the configuration of the display device 400. The display device 362 includes a plurality of pixels 410 arranged in a matrix. 400 includes a circuit GD and a circuit SD. Also, a plurality of pixels 410 arranged in a direction R, A plurality of wirings G1, a plurality of wirings G2, a plurality of wirings ANO, and Also, the pixel 410 arranged in the direction C and the circuit SD The semiconductor device has a plurality of wirings S1 and a plurality of wirings S2 electrically connected to the semiconductor device.

[0115] For simplicity, a configuration having one circuit GD and one circuit SD is shown here. A circuit GD and a circuit SD for driving the crystal element, and a circuit GD and a circuit S for driving the light-emitting element D may be provided separately.

[0116] The pixel 410 has a reflective liquid crystal element and a light emitting element. The substrate and the light emitting element have an overlapping portion.

[0117] FIG. 15B1 shows a configuration example of the conductive layer 311b included in the pixel 410. The conductive layer 311b functions as a reflective electrode of the liquid crystal element in the pixel 410. , an opening 451 is provided.

[0118] In FIG. 15(B1), the light emitting element 360 located in the area overlapping with the conductive layer 311b is indicated by a dashed line. The light-emitting element 360 is disposed so as to overlap the opening 451 of the conductive layer 311b. As a result, the light emitted by the light emitting element 360 is emitted to the display surface side through the opening 451. can be.

[0119] In FIG. 15(B1), pixels 410 adjacent in the direction R correspond to different colors. At this time, as shown in FIG. 15(B1), in two pixels adjacent to each other in the direction R, the openings 4 51 are provided at different positions on the conductive layer 311b so as not to be arranged in a line. This is preferable. It is possible to separate the two light emitting elements 360, and the light emitting elements 360 emit light. This phenomenon occurs when light coming from the same pixel is incident on the colored layer of an adjacent pixel 410 (also known as crosstalk). In addition, by arranging two adjacent light emitting elements 360 apart from each other, Therefore, in the case where the EL layer of the light emitting element 360 is separately produced by using a shadow mask or the like, Even so, a high-definition display device can be realized.

[0120] Alternatively, the arrangement may be as shown in FIG.

[0121] If the ratio of the total area of ​​the openings 451 to the total area of ​​the non-openings is too large, The display becomes dark. Also, the ratio of the total area of ​​the openings 451 to the total area of ​​the non-openings If the value is too small, the display using the light emitting element 360 will be too dark.

[0122] In addition, the area of ​​the opening 451 provided in the conductive layer 311b functioning as a reflective electrode is too small. As a result, the efficiency of light that can be extracted from the light emitted by the light emitting element 360 decreases.

[0123] The shape of the opening 451 may be, for example, a polygon, a rectangle, an ellipse, a circle, a cross, or the like. The shape may also be thin stripes, slits, or a checkered pattern. The apertures 451 may be arranged close to adjacent pixels. The pixels are arranged close to the other pixels to be displayed, which helps to suppress crosstalk.

[0124] [Circuit configuration example] 16 is a circuit diagram showing a configuration example of a pixel 410. In FIG. 16, two adjacent pixels It shows 410.

[0125] The pixel 410 includes a switch SW1, a capacitance element C1, a liquid crystal element 340, a switch SW2, and a transistor. The pixel 410 includes a transistor M, a capacitance element C2, and a light emitting element 360. , wire G1, wire G2, wire ANO, wire CSCOM, wire S1, and wire S2 are electrically 16, the wiring VCO M1, and a wiring VCOM2 electrically connected to the light-emitting element 360 are shown.

[0126] FIG. 16 shows an example in which transistors are used for the switches SW1 and SW2. This shows that.

[0127] The switch SW1 has a gate connected to the wiring G1 and either the source or the drain connected to the wiring S1, and the other of the source and drain is connected to one electrode of the capacitance element C1 and the liquid crystal One electrode of the capacitance element C1 is connected to the wiring CSCO The other electrode of the liquid crystal element 340 is connected to the wiring VCOM1. .

[0128] The switch SW2 has a gate connected to the wiring G2 and a source or drain The other of the source and drain is connected to one electrode of the capacitance element C2. The other electrode of the capacitance element C2 is connected to the gate of the transistor M. The transistor M is connected to either the source or drain of the transistor M1 and the wiring ANO. The other of the source and the drain is connected to one electrode of the light-emitting element 360. The other electrode of terminal 360 is connected to wiring VCOM2.

[0129] In FIG. 16, a transistor M has two gates that sandwich a semiconductor. These are connected to form This increases the current that the transistor M can pass. It is possible.

[0130] A signal for controlling the switch SW1 to a conductive state or a non-conductive state is applied to the wiring G1. A predetermined potential can be applied to the wiring VCOM1. A signal for controlling the alignment state of the liquid crystal of the liquid crystal element 340 can be applied. The OM can be given a predetermined electrical potential.

[0131] A signal for controlling the switch SW2 to a conductive state or a non-conductive state is applied to the wiring G2. A potential difference that causes the light emitting element 360 to emit light is generated between the wiring VCOM2 and the wiring ANO. The wiring S2 can be connected to a potential that causes the transistor M to be turned on or off. A signal to control the same can be given.

[0132] In the pixel 410 shown in FIG. 16, for example, when performing a reflective mode display, the wiring G1 and The liquid crystal element 340 is driven by a signal applied to the wiring S1 and displays the image by optical modulation. In addition, when displaying in a transmissive mode, the wiring G2 and the wiring S2 are provided with The light emitting element 360 can be driven by a signal to emit light for display. When driving in this mode, the wiring G1, the wiring G2, the wiring S1, and the wiring S2 are The input signal can be driven by a signal applied to the

[0133] In FIG. 16, one pixel 410 includes one liquid crystal element 340 and one light emitting element 360. 17A shows an example in which one pixel 410 has one The liquid crystal element 340 and the four light-emitting elements 360 (light-emitting elements 360r, 360g, 360b, An example with a diameter of 60w is shown.

[0134] In FIG. 17A, in addition to the example of FIG. 16, a line G3 and a line S3 are connected to a pixel 410. It is being done.

[0135] In the example shown in FIG. 17A, for example, four light emitting elements 360 are arranged as red (R), green (G), Light-emitting elements that exhibit green (G), blue (B), and white (W) colors can be used. A reflective liquid crystal element that exhibits white color can be used as the liquid crystal element 340. Therefore, when performing display in reflective mode, it is possible to display white with high reflectance. When display is performed in a transmissive mode, display with high color rendering can be achieved with low power consumption.

[0136] 17B shows a configuration example of a pixel 410. The pixel 410 has an electrode 31 A light emitting element 360w overlaps with an opening of the electrode 311, and a light emitting element disposed around the electrode 311. 360r, light emitting element 360g, and light emitting element 360b. It is preferable that the light emitting element 360g and the light emitting element 360b have substantially the same light emitting area. stomach.

[0137] [Display panel configuration example] FIG. 18 is a perspective schematic diagram of a display panel 300 according to an embodiment of the present invention. 18 has a structure in which a substrate 351 and a substrate 361 are bonded together. is indicated by a dashed line.

[0138] The display panel 300 includes a display unit 362, a circuit 364, wiring 365, etc. For example, the circuit 364, the wiring 365, the conductive layer 311b functioning as a pixel electrode, etc. In FIG. 18, an IC 373 and an FPC 372 are mounted on a board 351. Therefore, the configuration shown in FIG. 18 includes the display panel 300, the FPC 372, and It can also be said to be a display module having the IC373.

[0139] The circuit 364 can be, for example, a circuit that functions as a scanning line driver circuit.

[0140] The wiring 365 has a function of supplying signals and power to the display unit and the circuit 364. Power is input to wiring 365 from the outside via FPC 372 or from IC 373.

[0141] In FIG. 18, the substrate 351 is formed by a COG (Chip On Glass) method or the like. The IC 373 is, for example, a scanning line driving circuit, Alternatively, an IC having a function as a signal line driver circuit or the like can be applied. 0 may have a circuit that functions as a scanning line driver circuit and a signal line driver circuit, or The display panel is connected to the outside via FPC372, and the circuits that function as the driving circuits and signal line driving circuits are provided. In cases such as when inputting a signal to drive panel 300, IC373 is not provided. Also, IC373 may be mounted by COF (Chip On Film) method, etc. It may also be mounted on FPC372.

[0142] FIG. 18 shows an enlarged view of a part of the display unit 362. The display unit 362 has a plurality of displays. The conductive layer 311b of the display element is arranged in a matrix. It has a function of reflecting visible light, and functions as a reflective electrode for the liquid crystal element 340 described later.

[0143] As shown in FIG. 18, the conductive layer 311b has an opening. The light emitting element 360 is disposed on the substrate 351 side. The light is emitted to the substrate 361 side through the opening of 1b.

[0144] [Cross-section example] FIG. 19 shows a part of the area including the FPC 372 and the circuit 36 ​​of the display panel shown in FIG. 4 and a part of the area including the display unit 362 are cut away. An example of a surface is shown below.

[0145] The display panel has an insulating layer 220 between a substrate 351 and a substrate 361. Between the insulating layer 220 and the light emitting element 360, the transistor 201a, the transistor 201b, and the insulating layer 220, b, the transistor 205, the transistor 206, the transistor 207, the colored layer 134, etc. In addition, the liquid crystal element 340, the colored layer 131, etc. are provided between the insulating layer 220 and the substrate 361. In addition, the substrate 361 and the insulating layer 220 are bonded via the adhesive layer 141, and the substrate 351 and the insulating layer 220 are bonded via the adhesive layer 141. The border layer 220 is attached via an adhesive layer 142 .

[0146] The transistor 206 is electrically connected to the liquid crystal element 340. 5 is electrically connected to the transistor 207, and the transistor 207 is electrically connected to the light emitting element 360. The transistor 205 and the transistor 206 are both connected to the insulating layer 220. Since they are formed on the surface of the plate 351, they can be manufactured using the same process. In addition, since the transistor 207 is formed to overlap with the transistor 205, The pixel size can be reduced. a region where the gate insulating film extends, and a region where either the source electrode or the drain electrode extends. In this region, the capacitive element C2 can be formed.

[0147] The substrate 361 includes a colored layer 131, a light-shielding layer 132, an insulating layer 121, and a liquid crystal element 340. A conductive layer 113 functioning as a common electrode, an alignment film 133b, an insulating layer 117, etc. are provided. The insulating layer 117 serves as a spacer for maintaining the cell gap of the liquid crystal element 340. It works.

[0148] On the substrate 351 side of the insulating layer 220, the insulating layer 211a, the insulating layer 212a, and the insulating layer 213a are , insulating layer 214a, insulating layer 215, insulating layer 211b, insulating layer 212b, insulating layer 213b, Insulating layers are provided, such as insulating layer 214b, insulating layer 216, etc.

[0149] A part of the insulating layer 211a functions as a gate insulating layer for the transistors 205 and 206. The insulating layer 212a, the insulating layer 213a, and the insulating layer 214a are It is installed covering 206.

[0150] A part of the insulating layer 211b functions as a gate insulating layer of the transistor 207. An edge layer 212b, an insulating layer 213b, and an insulating layer 214b are disposed over the transistor 207. It is being done.

[0151] The insulating layer 214a and the insulating layer 214b function as planarizing layers. The above shows a case where the insulating layer covering the transistors, etc. is three layers, but this is not limited to this. It may be four or more layers, a single layer, or two layers. The insulating layer 214a and the insulating layer 214b may not be provided if they are not necessary. 1 shows a case where an insulating layer 215 is provided between the insulating layer 214a and the insulating layer 211b. However, the insulating layer 215 is not necessarily provided.

[0152] In addition, the transistors 205, 206, and 207 are partially A conductive layer 221 that functions as a gate, and a conductive layer in part that functions as a source or drain 222 and a semiconductor layer 231.

[0153] The liquid crystal element 340 is a reflective liquid crystal element. The liquid crystal element 340 includes a conductive layer 311a, a liquid crystal The conductive layer 311a has a laminated structure in which the conductive layer 312 and the conductive layer 113 are laminated. A conductive layer 311b that reflects visible light is provided on the side of the conductive layer 311b. 251. The conductive layer 311a and the conductive layer 113 contain a material that transmits visible light. In addition, an alignment film 133a is provided between the liquid crystal 112 and the conductive layer 311a. An alignment film 133b is provided between the layers 113. Also, the outer surface of the substrate 361 is provided with a polarizing film. It has an optical plate 130.

[0154] In the liquid crystal element 340, the conductive layer 311b has a function of reflecting visible light, and the conductive layer 11 The light incident from the substrate 361 side is polarized by the polarizing plate 130. The light is polarized in a circular direction, passes through the conductive layer 113 and the liquid crystal 112, and is reflected by the conductive layer 311b. The light passes through the crystal 112 and the conductive layer 113 again and reaches the polarizing plate 130. The orientation of the liquid crystal is controlled by applying a voltage between 311b and the conductive layer 113, and optical modulation of light is performed. That is, the intensity of the light emitted through the polarizing plate 130 can be controlled. In addition, the colored layer 131 can absorb light outside a specific wavelength range. As a result, the extracted light exhibits, for example, red color.

[0155] The light emitting element 360 is a bottom emission type light emitting element. A laminate in which a conductive layer 191, an EL layer 192, and a conductive layer 193b are laminated in this order from the layer 220 side. The conductive layer 193a is provided to cover the conductive layer 193b. The conductive layer 191 and the conductive layer 193b contain a material that reflects visible light. The light emitted by the light emitting element 360 passes through the colored layer 134, the insulating layer 220, the opening 251, and is emitted to the substrate 361 side via the conductive layer 113 and the like.

[0156] As shown in FIG. 19, the opening 251 is provided with a conductive layer 311a that transmits visible light. In this way, even in the area overlapping with the opening 251, Since the liquid crystal 112 is oriented in the same manner as in the other regions, poor alignment of the liquid crystal occurs at the boundary between these regions. This can prevent unintended light leakage.

[0157] Here, a linear polarizing plate may be used as the polarizing plate 130 disposed on the outer surface of the substrate 361. However, a circular polarizer can also be used. For example, a linear polarizer and a 1 / 4 wave A laminate of long retardation plates can be used. This can suppress the reflection of external light. In addition, the cell gap of the liquid crystal element used in the liquid crystal element 340 can be adjusted according to the type of the polarizing plate. By adjusting the flip-flop, orientation, driving voltage, etc., the desired contrast can be achieved. good.

[0158] Moreover, an insulating layer 217 is provided on the insulating layer 216 covering the end of the conductive layer 191. The insulating layer 217 has a spacer that prevents the insulating layer 220 and the substrate 351 from coming closer than necessary. The EL layer 192 and the conductive layer 193a are also shielded by a shielding mask (metal mask). When a mask is used to form the mask, the mask is prevented from coming into contact with the surface to be formed. Note that the insulating layer 217 does not have to be provided if it is not necessary.

[0159] One of the source and drain of the transistor 207 is connected to the light-emitting element via the conductive layer 191. It is electrically connected to the EL layer 192 of 360 .

[0160] One of the source and drain of the transistor 206 is connected to the conductive layer 3 via a connection 208. The conductive layer 311b and the conductive layer 311a are provided in contact with each other. These are electrically connected. Here, the connection portion 208 is provided on the insulating layer 220. This is a portion that connects the conductive layers provided on both sides of the insulating layer 220 together via the opening.

[0161] A connection portion 204 is provided in the area where the substrate 351 and the substrate 361 do not overlap. The connection portion 204 is electrically connected to the FPC 372 via the connection layer 242. The upper surface of the connection portion 204 is a conductive layer 311a. The conductive layer obtained by processing the same conductive film is exposed. It can be electrically connected to PC372 via a connection layer 242.

[0162] A connection portion 252 is provided in a portion of the area where the adhesive layer 141 is provided. In 52, a conductive layer obtained by processing the same conductive film as the conductive layer 311a and a conductive layer 11 3 is electrically connected to the substrate 361 by the connector 243. A signal input from the FPC 372 connected to the substrate 351 side is input to the formed conductive layer 113. Alternatively, the potential can be supplied via connection 252 .

[0163] The connector 243 may be, for example, a conductive particle. For this purpose, it is possible to use particles of organic resin or silica coated with a metal material. It is preferable to use nickel or gold as the metal material because it is possible to reduce the contact resistance. Particles coated with layers of two or more metal materials, such as nickel coated with gold, are It is preferable to use a material that is elastically deformable or plastically deformable as the connector 243. In this case, the connectors 243, which are conductive particles, are preferably used as shown in FIG. In this way, the connector 243 and the electric This increases the contact area with the electrically conductive layer, reducing contact resistance and preventing connection failures. The occurrence of such defects can be suppressed.

[0164] The connector 243 is preferably disposed so as to be covered with the adhesive layer 141. For example, The connectors 243 may be dispersed on the previous adhesive layer 141 .

[0165] In FIG. 19, transistors 201a and 201b are provided as an example of a circuit 364. An example is shown.

[0166] The transistor 201a can be manufactured in the same process as the transistors 205 and 206. In addition, the transistor 201b can be manufactured in the same process as the transistor 207. can.

[0167] Note that the transistors in the circuit 364 and the transistors in the display portion 362 are the same. The transistors in the circuit 364 may all have the same structure. Alternatively, transistors having different structures may be used in combination. The multiple transistors in 362 may all have the same structure, or may have different structures. Transistors may also be used in combination.

[0168] At least one of the insulating layers 212a and 213a that cover the transistors and the insulating layer At least one of the insulating layer 212b and the insulating layer 213b is free from impurities such as water and hydrogen. It is preferable to use a material that is difficult to break down. At least one of the insulating layers 212b and 213b is a barrier film. By adopting such a configuration, the external This effectively prevents impurities from diffusing from the display panel, resulting in highly reliable display panels. This makes it possible to realize the above-mentioned network.

[0169] On the substrate 361 side, an insulating layer 121 is provided to cover the colored layer 131 and the light-shielding layer 132. The insulating layer 121 may function as a planarizing layer. Since the surface of the conductive layer 113 can be made substantially flat, the alignment state of the liquid crystal 112 can be made uniform. .

[0170] [About each component] Each of the above components will be described below.

[0171] 〔substrate〕 A material having a flat surface can be used for the substrate of the display panel. The substrate from which the light is extracted is made of a material that transmits the light. For example, glass, quartz, Materials such as ceramic, sapphire, and organic resins can be used.

[0172] By using a thin substrate, the display panel can be made lighter and thinner. Furthermore, by using a substrate having a thickness sufficient to provide flexibility, a flexible display panel can be realized. It can be realized.

[0173] In addition, the substrate on the side from which light is not extracted does not need to have light-transmitting properties. In addition to the above-mentioned substrate, a metal substrate or the like can also be used. Metal substrates have high thermal conductivity and the entire substrate Since heat can be easily transferred to the body, localized temperature increases in the display panel can be suppressed. In order to obtain flexibility and bendability, the thickness of the metal substrate is preferably 10 μm or more and 200 μm or less. The thickness is preferably 20 μm or less and more preferably 50 μm or less.

[0174] The material constituting the metal substrate is not particularly limited, but examples thereof include aluminum, copper, and nickel. Metals such as nickel, or alloys such as aluminum alloys and stainless steel are preferably used. It is possible.

[0175] In addition, insulating treatment is performed by oxidizing the surface of the metal substrate or forming an insulating film on the surface. For example, a coating method such as spin coating or dipping may be used. The insulating film may be formed by electrodeposition, vapor deposition, sputtering, or the like. In addition to leaving it in an atmosphere or heating it, an oxide film is formed on the surface of the substrate by anodizing or other methods. It may be formed.

[0176] As a material that is flexible and transparent to visible light, for example, polyethylene terephthalate is used. Polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), Polyacrylonitrile resin, polyimide resin, polymethyl methacrylate resin, polycarbonate Polycarbonate (PC) resin, Polyethersulfone (PES) resin, Polyamide resin, Cyclo Olefin resin, polystyrene resin, polyamide-imide resin, polyvinyl chloride resin, poly Tetrafluoroethylene (PTFE) resin, etc. In particular, materials with a low thermal expansion coefficient For example, a thermal expansion coefficient of 30×10 -6 Polyamides below / K The material that can be suitably used is a resin such as an imide resin, a polyimide resin, or PET. Substrates with fibers impregnated with organic resin or substrates with inorganic fillers mixed into organic resin to reduce the thermal expansion coefficient. A substrate made of such a material is light in weight, so that the substrate can be easily mounted. The display panel used can also be made lightweight.

[0177] When the above-mentioned materials contain fibrous bodies, the fibrous bodies are made of high strength organic or inorganic compounds. High strength fibers are specifically fibers with high tensile modulus or Young's modulus. Representative examples are polyvinyl alcohol fibers, polyester fibers, and polyvinyl alcohol fibers. Mid fiber, polyethylene fiber, aramid fiber, polyparaphenylene benzobisoxy Examples of the fiberglass include Sasol fiber, glass fiber, and carbon fiber. Examples of glass fibers include those made of glass fiber such as sappan, S-glass, D-glass, and Q-glass. Alternatively, it is used in the form of a nonwoven fabric, and the structure in which the fiber body is impregnated with resin and the resin is hardened is formed by using a microfiber. The flexible substrate may be a substrate made of a fiber and a resin. The use of such a structure is preferred because it improves reliability against damage caused by bending or localized pressure. It is nice.

[0178] Alternatively, glass, metal, or the like that is thin enough to be flexible may be used for the substrate. Alternatively, a composite material in which glass and a resin material are bonded together with an adhesive layer may be used.

[0179] A hard coat layer (e.g., For example, silicon nitride, aluminum oxide, etc.) or a layer of material capable of dispersing pressure (for example, aluminum In addition, the life of the display element may be reduced by moisture, etc. In order to suppress the above, an insulating film with low water permeability may be laminated on a flexible substrate. For example, silicon nitride, silicon oxynitride, silicon nitride oxide, aluminum oxide, nitrogen For example, an inorganic insulating material such as aluminum oxide can be used.

[0180] The substrate may be formed by laminating a plurality of layers. In particular, the substrate may have a glass layer. This improves the barrier properties against water and oxygen, making it possible to provide a highly reliable display panel. .

[0181] [Transistor] The transistor includes a conductive layer functioning as a gate electrode, a semiconductor layer, and a A conductive layer that functions as a drain electrode and a conductive layer that functions as a gate insulating layer. The above describes the case where a bottom-gate transistor is used. is.

[0182] Note that the structure of a transistor included in a display device of one embodiment of the present invention is not particularly limited. For example, a planar type transistor or a staggered type transistor may be used. Alternatively, a top-gate or bottom-gate transistor may be used. Alternatively, gate electrodes may be provided above and below the channel. It may be possible to use

[0183] The crystallinity of the semiconductor material used in the transistor is not particularly limited. Semiconductors with crystallinity (microcrystalline semiconductors, polycrystalline semiconductors, single crystal semiconductors, or partially crystalline semiconductors) If a semiconductor having crystallinity is used, the transistor This is preferable because it is possible to suppress deterioration of the transistor characteristics.

[0184] In addition, the semiconductor material used in transistors must have an energy gap of 2 eV or more. It is preferable to use a metal oxide having a polarization energy of 2.5 eV or more, and more preferably 3 eV or more. A typical example is an oxide semiconductor containing indium. C-OS, etc. can be used.

[0185] Using oxide semiconductors that have a wider band gap and lower carrier density than silicon The transistor has a low off-state current, so the capacitance element connected in series with the transistor It is possible for the charge stored in the capacitor to be held for a long period of time.

[0186] The semiconductor layer may be, for example, indium, zinc, and M (aluminum, titanium, gallium, germanium, etc.). Rumanium, yttrium, zirconium, lanthanum, cerium, tin, neodymium or The film can be expressed as an In-M-Zn oxide film containing metals such as hafnium. .

[0187] When the oxide semiconductor constituting the semiconductor layer is an In-M-Zn oxide, The atomic ratio of metal elements in the sputtering target used to form a film of the oxide is In≧ It is preferable that M and Zn satisfy the condition M. The atomic ratio of In:M:Zn is 1:1:1, In:M:Zn is 1:1:1.2, and I n:M:Zn=3:1:2, In:M:Zn=4:2:3, In:M:Zn=4:2:4 .1, In:M:Zn=5:1:6, In:M:Zn=5:1:7, In:M:Zn=5 The atomic ratio of the metal elements in the semiconductor layer to be formed is preferably 1:1:8. The atomic ratio of the metal elements contained in the sputtering target is within ±40%. Includes fluctuations.

[0188] The bottom-gate transistor described in this embodiment can reduce the manufacturing process. In addition, the use of an oxide semiconductor allows the film to be formed at a lower temperature than polycrystalline silicon. This allows the use of low heat resistance materials as wiring and electrode materials below the semiconductor layer and as substrate materials. The range of materials that can be used is widened. For example, A multi-layer glass substrate or the like can be suitably used.

[0189] For the semiconductor layer, an oxide semiconductor film having a low carrier density is used. For example, , the carrier density is 1×10 17 / cm 3 Less than or equal to 1×10 15 / cm 3 Below, More preferably, 1×1013 / cm 3 Less than or equal to 1×10 11 / cm 3 below, More preferably, 1×10 10 / cm 3 Less than 1 x 10 -9 / cm 3 More than 10 ... Such oxide semiconductors can be used as high-purity intrinsic or substantially high-purity oxide semiconductors. This is called an intrinsic oxide semiconductor. This has a low impurity concentration and a low defect state density. Therefore, it can be said that the oxide semiconductor has stable characteristics.

[0190] In addition, the semiconductor characteristics and electrical characteristics (electric field characteristics) of the required transistors are not limited to these. It is sufficient to use a material with an appropriate composition depending on the characteristics of the material (e.g., effective mobility, threshold voltage, etc.). In order to obtain the semiconductor characteristics of a transistor, the carrier density, impurity concentration, and defect density of the semiconductor layer are It is preferable to appropriately set the recess density, the atomic ratio of metal elements to oxygen, the interatomic distance, the density, etc. It is nice.

[0191] In the oxide semiconductor that constitutes the semiconductor layer, silicon and carbon, which are group 14 elements, If oxygen is contained in the semiconductor layer, oxygen vacancies increase and the semiconductor layer becomes n-type. The concentrations of silicon and carbon in the body layer (obtained by secondary ion mass spectrometry) were ×10 18 atoms / cm 3 Less than or equal to 2 x 10 17 atoms / cm 3 Below and do.

[0192] In addition, when alkali metals and alkaline earth metals combine with oxide semiconductors, they form carriers. This can cause the off-state current of a transistor to increase. Alkali metal or alkaline earth metals in the conductor layer obtained by secondary ion mass spectrometry The concentration of the genus is 1×10 18 atoms / cm 3 Less than or equal to 2 x 10 16 atoms / cm 3 To the following:

[0193] In addition, when nitrogen is contained in the oxide semiconductor that constitutes the semiconductor layer, the electron This causes an increase in carrier density, making it easier to convert to n-type. Transistors using semiconductors tend to be normally-on. The nitrogen concentration obtained by secondary ion mass spectrometry in 18 atoms / cm 3 It is preferable to do the following:

[0194] The semiconductor layer may have a non-single crystal structure. The non-single crystal structure may have a non-single crystal structure, for example, a structure in which the crystal is aligned along the c-axis. CAAC-OS (C-Axis Aligned Crystallography) ine Oxide Semiconductor, or C-Axis Align ed and AB-plane Anchored Crystalline Ox ide Semiconductor), polycrystalline, microcrystalline, or amorphous structure Among non-single crystal structures, the amorphous structure has the highest density of defect states, and CAAC-OS has The defect level density is the lowest.

[0195] An oxide semiconductor film having an amorphous structure has, for example, a disordered atomic arrangement and does not contain a crystalline component. Alternatively, the oxide film having an amorphous structure is, for example, a completely amorphous structure without any crystalline portion. do not have.

[0196] Note that the semiconductor layer may be a mixed film having two or more of an amorphous structure region, a microcrystalline structure region, a polycrystalline structure region, a CAA C-OS region, and a single crystal structure region. The mixed film may have, for example, a single layer structure including any two or more of the above-described regions, or a stacked layer structure.

[0197] <Configuration of CAC-OS> Hereinafter, the configuration of CAC (C loud-Aligned Composite)-OS that can be used for the transistor disclosed in one aspect of the present invention will be described.

[0198] CAC-OS is, for example, a material configuration in which elements constituting an oxide semiconductor are unevenly distributed in a size of 0.5 nm or more and 10 nm or less, preferably 1 nm or more and 2 nm or less, or in the vicinity thereof. Note that hereinafter, in the oxide semiconductor, one or more metal elements are unevenly distributed, and a region having the metal element is mixed in a size of 0.5 nm or more and 10 nm or less, preferably 1n m or more and 2 nm or less, or in the vicinity thereof, and this state is also referred to as a mosaic state or a patch state.

[0199] Note that the oxide semiconductor preferably contains at least indium. In particular, indium and zinc are preferably contained. In addition to these, one or more selected from aluminum, gallium, yttrium, copper, vanadium, beryllium, boron, silicon, titanium, iron, nickel, yttrium, copper, vanadium, beryllium, boron, silicon, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium

[0200] ​​​For example, CAC-OS in In-Ga-Zn oxide (In- The Ga-Zn oxide may be specifically referred to as CAC-IGZO. (hereinafter referred to as InO X1 (X1 is a real number greater than 0.) or Indium Zinc Oxide (hereinafter, In X2 Zinc Y2 O Z2 (X2, Y2, and Z2 are real numbers greater than 0. ) and gallium oxide (GaO X3 (X3 is a real number greater than 0) ), or gallium zinc oxide (Ga X4 Zinc Y4 O Z4 (X4, Y4, and Z1 and Z2 are real numbers greater than 0.) The material is separated into a mosaic pattern. The mosaic-like InO X1 , or In X2 Zinc Y2 O Z2 is distributed uniformly in the film. This is a configuration (hereinafter also referred to as a cloud-like configuration).

[0201] In other words, CAC-OS is X3 The region where In is the main component and X2 Zinc Y2 O Z2 , or InO X1 A composite oxide semiconductor having a structure in which a region in which In this specification, for example, the number of In atoms relative to the element M in the first region is The first region has a ratio of In to the element M that is greater than the atomic ratio of In to the element M in the second region. It is assumed that the concentration of In is higher than that of the second region.

[0202] IGZO is a common name and refers to a compound made of In, Ga, Zn, and O. A typical example is InGaO3(ZnO). m1 (m1 is a natural number), or In (1+x0) Ga (1-x0) O3(ZnO) m0 (-1≦x0≦1, m0 is an arbitrary number) Examples of the crystalline compound include those represented by the following formula:

[0203] The crystalline compound has a single crystal structure, a polycrystalline structure, or a CAAC structure. The CAAC structure is a structure in which multiple IGZO nanocrystals have a c-axis orientation and are aligned on the ab plane. In the case of ZnO, the crystal structure is non-oriented and connected.

[0204] On the other hand, CAC-OS refers to the material composition of an oxide semiconductor. In a material composition containing Ga, Zn, and O, some of the nanoparticles are mainly composed of Ga. The region where In is observed as a nanoparticle and the region where In is observed as a nanoparticle are mainly composed of In are shown in Fig. Therefore, in CAC-OS, The crystal structure is a secondary factor.

[0205] Note that CAC-OS does not include a laminated structure of two or more films with different compositions. For example, a structure consisting of two layers, one containing In as the main component and the other containing Ga as the main component, Not at all.

[0206] In addition, GaO X3 The region where In is the main component and X2 Zinc Y2 O Z2 , or InO X1 In some cases, it may be difficult to observe a clear boundary between the region in which the main component is the

[0207] Instead of gallium, aluminum, yttrium, copper, vanadium, and beryllium are used. Aluminum, boron, silicon, titanium, iron, nickel, germanium, zirconium, molybdenum lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium If one or more selected species from the group consisting of uranium, uranium, etc. are included, CAC-OS will In one area, the metal element is observed as a nanoparticle, and in another area, In is observed as a nanoparticle. The nanoparticle-like regions are randomly distributed in a mosaic pattern. This refers to.

[0208] CAC-OS can be formed, for example, by a sputtering method without heating the substrate. In addition, when the CAC-OS is formed by a sputtering method, the following deposition gas is used: Any one of an inert gas (typically argon) and oxygen gas. In addition, the flow rate ratio of oxygen gas to the total flow rate of the deposition gas during deposition is low. For example, the flow rate ratio of oxygen gas is set to 0% or more and less than 30%, preferably 0% or more and less than 10%. It is preferable to set it to 0% or less.

[0209] CAC-OS is a method for measuring X-ray diffraction (XRD). When measured using the out-of-plane θ / 2θ scan, In other words, no clear peaks are observed in the measurement area from the X-ray diffraction. It can be seen that the orientation of the regions in the ab plane direction and the c-axis direction is not observed.

[0210] In addition, CAC-OS uses an electron beam with a probe diameter of 1 nm (also called a nanobeam electron beam). In the electron beam diffraction pattern obtained by irradiating the sample with light, a ring-shaped region of high brightness and Several bright spots are observed in the ring region. Therefore, from the electron diffraction pattern, it is confirmed that CAC-O The crystal structure of S is nc (nano) which has no orientation in the planar direction and cross-sectional direction. -crystal structure.

[0211] For example, in the case of CAC-OS using In-Ga-Zn oxide, the energy dispersive X-ray spectroscopy (EDX: Energy Dispersive X-ray spectrometry) The EDX mapping obtained using oscopy revealed that GaO X3 The area where is the main component Area and In X2 Zinc Y2 O Z2 , or InO X1 The areas where the main component is It can be confirmed that the structure matches.

[0212] CAC-OS has a structure different from that of IGZO compounds in which metal elements are uniformly distributed. It has different properties from GZO compounds. That is, CAC-OS is GaO X3 The main components are and the region where In X2 Zinc Y2 O Z2 , or InO X1 The region where is the main component and the region where is The phase is gradually separated, and the regions each consisting of one element as a main component are arranged in a mosaic pattern.

[0213] Here, In X2 Zinc Y2 O Z2 , or InO X1 The area where GaO is the main component X This is a region with high conductivity compared to the region where In 3 is the main component. X2 Zinc Y2 O Z2 , or InO X1 The carriers flow through the area where the main component is oxygen. Therefore, the conductivity of In is expressed as a semiconductor. X2 Zinc Y2 O Z2 , or InO X1 The region where the main component is a metal is distributed in a cloud-like shape in the oxide semiconductor, which results in a high electric field efficiency. As a result, a high mobility (μ) can be achieved.

[0214] On the other hand, GaO X3 The region where the main components are In X2 Zinc Y2 O Z2 , or InO X1 This region has higher insulating properties than the region where GaO is the main component. X3 etc. By distributing the region in which the main component is Switching operation can be achieved.

[0215] Therefore, when CAC-OS is used in a semiconductor device, GaO X3 Insulation due to Sex and In X2 Zinc Y2 O Z2 , or InO X1 The conductivity caused by the This allows for a high on-state current (I on ), and high field-effect mobility (μ It is possible.

[0216] In addition, semiconductor devices using CAC-OS have high reliability. It is ideal for a variety of semiconductor devices including displays.

[0217] Alternatively, silicon may be used as the semiconductor in which the channel of the transistor is formed. Although amorphous silicon may be used as the capacitor, it is particularly preferable to use silicon having crystallinity. For example, microcrystalline silicon, polycrystalline silicon, single crystal silicon, etc. are used. In particular, polycrystalline silicon can be formed at a lower temperature than single crystal silicon. It also has higher field effect mobility and higher reliability than amorphous silicon.

[0218] The bottom-gate transistor described in this embodiment can reduce the manufacturing process. In addition, the use of amorphous silicon in this case is preferable compared to polycrystalline silicon. Since it can be formed at low temperatures, it is highly resistant and can be used as a material for wiring and electrodes below the semiconductor layer, and as a material for substrates. The possibility of using low-heat materials allows for a wider range of material choices. For example, a very large glass substrate can be used. Since the impurity region of the transistor is easily formed in a self-aligned manner, the characteristics of the transistor are not uniform. In this case, it is preferable to use polycrystalline silicon or single crystal silicon. This is suitable for use in situations where

[0219] [Conductive Layer] In addition to the gates, sources, and drains of transistors, various wiring and Materials that can be used for the conductive layers such as electrodes include aluminum, titanium, chromium, and titanium alloys. Aluminum, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, or thallium Examples of the metals include tin and tin oxide, and alloys containing tin as the main component. Films containing the materials can be used as single layers or as multilayer structures. For example, silicon A single-layer structure of an aluminum film containing titanium, a two-layer structure of an aluminum film laminated on a titanium film, A two-layer structure in which an aluminum film is laminated on a stainless steel film, and a copper-magnesium-aluminum alloy Two-layer structure with copper film laminated on gold film, two-layer structure with copper film laminated on titanium film, tungsten A two-layer structure in which a copper film is laminated on top of a titanium film or titanium nitride film is laminated on top of that with an aluminum film. A titanium or copper film is laminated on top of the titanium or titanium nitride film. Layer structure, molybdenum film or molybdenum nitride film, and aluminum film or A three-layer structure in which a copper film is laminated and a molybdenum film or molybdenum nitride film is further formed on top of the copper film. Incidentally, oxides such as indium oxide, tin oxide, and zinc oxide may also be used. In addition, the use of copper containing manganese is preferable because it improves the controllability of the shape by etching. .

[0220] Examples of the conductive material having a light-transmitting property include indium oxide, indium tin oxide, and indium tin oxide. Conductive oxides such as indium zinc oxide, zinc oxide, zinc oxide doped with gallium, or Graphene can be used. Alternatively, gold, silver, platinum, magnesium, nickel, tin, etc. such as tin, chromium, molybdenum, iron, cobalt, copper, palladium, or titanium. Metallic materials and alloy materials containing the metallic materials can be used. Alternatively, a metal material, an alloy material (or a combination thereof) may be used. In the case of using these nitrides, it is sufficient to make them thin enough to have light transmission. A laminated film of a material can be used as the conductive layer. For example, a silver-magnesium alloy and an insulator can be used. It is preferable to use a laminated film of dilute tin oxide or the like, since the electrical conductivity can be increased. These include conductive layers such as various wiring and electrodes that constitute the display device, and conductive layers of the display element. The conductive layer may also be used as a pixel electrode or a common electrode.

[0221] [Insulating layer] Examples of insulating materials that can be used for each insulating layer include acrylic and epoxy. In addition to resins and resins with siloxane bonds, silicon oxide, silicon oxynitride, silicon oxynitride Inorganic insulating materials such as silicon, silicon nitride, and aluminum oxide can also be used.

[0222] In addition, the light emitting element is preferably provided between a pair of insulating films with low water permeability. This makes it possible to prevent impurities such as water from entering the light emitting element, and thus prevents a decrease in the reliability of the device. It can be suppressed.

[0223] Insulating films with low water permeability include silicon nitride films and silicon oxynitride films, which are made of nitrogen and silicon. and films containing nitrogen and aluminum, such as an aluminum nitride film. A silicon oxide film, a silicon oxynitride film, an aluminum oxide film, or the like may also be used.

[0224] For example, the water vapor permeability of a low-permeability insulating film is 1×10 -5 [g / (m 2 ·day) ] or less, preferably 1 × 10 -6 [g / (m 2 ·day)] or less, preferably 1×1 0 -7 [g / (m 2 ·day)] or less, and more preferably 1×10 -8 [g / (m 2 d ay)] below.

[0225] [Liquid crystal element] The liquid crystal element may be, for example, a vertical alignment (VA) A liquid crystal element in which the vertical alignment mode is applied can be used. Multi-Domain Vertical Alignment mode, PVA( Patterned Vertical Alignment) mode, ASV (Adv Anced Super View mode, etc. can be used.

[0226] In addition, the liquid crystal element may be a liquid crystal element to which various modes are applied. For example, in addition to VA mode, TN (Twisted Nematic) mode, IPS (In -Plane-Switching mode, FFS (Fringe Field Switching) mode itching) mode, ASM(Axially Symmetric aligne) d Micro-cell mode, OCB (Optically Compensated ed Birefringence mode, FLC (Ferroelectric L iquid Crystal mode, AFLC (AntiFerroelectric) Liquid crystal elements using the Liquid Crystal (LC) mode can be used. .

[0227] The liquid crystal element is a device that controls the transmission or non-transmission of light by the optical modulation action of liquid crystal. The optical modulation of liquid crystals is achieved by the electric field applied to the liquid crystal (horizontal electric field, vertical electric field). The liquid crystal used in the liquid crystal element is controlled by a These include thermotropic liquid crystal, low molecular weight liquid crystal, polymer liquid crystal, and polymer dispersed liquid crystal (PDLC). : Polymer Dispersed Liquid Crystal), Ferroelectric Liquid These liquid crystal materials can be used as colloidal liquid crystals, antiferroelectric liquid crystals, etc. It shows telic phase, smectic phase, cubic phase, chiral nematic phase, isotropic phase, etc. .

[0228] As the liquid crystal material, either a positive type liquid crystal or a negative type liquid crystal may be used. It is only necessary to use an optimum liquid crystal material depending on the mode and design to be applied.

[0229] In addition, an alignment film can be provided to control the alignment of the liquid crystal. When adopting this method, liquid crystals exhibiting a blue phase without using an alignment film may be used. When the temperature of a cholesteric liquid crystal is increased, the cholesteric phase changes to the isotropic phase. The blue phase appears only in a narrow temperature range, so it is difficult to distinguish between the two. In order to improve the range, a liquid crystal composition containing a chiral agent of several weight percent or more is used in the liquid crystal layer. A liquid crystal composition containing a liquid crystal exhibiting a blue phase and a chiral agent has a short response time and optically isotropic In addition, the liquid crystal composition containing the liquid crystal exhibiting the blue phase and the chiral agent does not require alignment treatment. In addition, no alignment film is required, and the viewing angle dependency is small. This prevents electrostatic damage caused by rubbing, and This can reduce defects and damage to the liquid crystal display device during the manufacturing process.

[0230] The liquid crystal element may be a transmissive liquid crystal element, a reflective liquid crystal element, or a semi-transmissive liquid crystal element. An element or the like can be used.

[0231] In one embodiment of the present invention, a reflective liquid crystal element can be used in particular.

[0232] When using a transmissive or semi-transmissive liquid crystal element, two polarizing A backlight is provided on the outer side of the polarizing plate. It may be a direct-light type backlight or an edge-light type backlight. Direct backlight equipped with LED (Light Emitting Diode) This makes local dimming easier and increases contrast. In addition, when an edge-light type backlight is used, the module including the backlight can be displayed more clearly. This is preferable because it allows the thickness of the module to be reduced.

[0233] When using a reflective liquid crystal element, a polarizing plate is provided on the display surface side. It is preferable to place a light diffusion plate on the display surface side, since this improves visibility.

[0234] In addition, when using a reflective or semi-transmissive liquid crystal element, a freon is placed on the outside of the polarizing plate. As the front light, an edge light type front light may be provided. It is preferable to use LED (Light Emitting Diode) The use of a front light is preferable since it reduces power consumption.

[0235] [Light-emitting element] The light-emitting element may be a self-emitting element that can emit light by applying a current or voltage. This category includes elements whose brightness can be controlled. For example, LEDs, organic EL elements, inorganic EL elements, etc. An L element or the like can be used.

[0236] The light-emitting elements are top emission type, bottom emission type, and dual emission type. The electrode that extracts the light uses a conductive film that transmits visible light. For the electrode on the side from which light is not extracted, it is preferable to use a conductive film that reflects visible light.

[0237] The EL layer has at least a light-emitting layer. The EL layer has a hole-injecting layer as a layer other than the light-emitting layer. high hole transporting material, hole blocking material, high electron transporting material, electron injection highly conductive or bipolar substances (substances with high electron transport and hole transport properties), etc. The film may further include a layer comprising:

[0238] The EL layer can be made of either low molecular weight or high molecular weight compounds. Each of the layers constituting the EL layer may be formed by deposition (including vacuum deposition). ), a transfer method, a printing method, an ink-jet method, a coating method, or the like.

[0239] When a voltage higher than the threshold voltage of the light-emitting element is applied between the cathode and anode, the EL layer is charged from the anode side. Holes are injected from the cathode side, and electrons are injected from the cathode side. The injected electrons and holes are These molecules recombine and the luminescent material contained in the EL layer emits light.

[0240] When a white-emitting light-emitting element is used as the light-emitting element, two or more types of light-emitting elements are used in the EL layer. For example, the light emitted by two or more luminescent materials may be of complementary colors. By selecting a light-emitting material so as to satisfy the above relationship, white light can be obtained. For example, Luminescent substances that emit light of R (red), G (green), B (blue), Y (yellow), O (orange), etc. Or, among luminescent materials that emit light containing two or more of the spectral components of R, G, and B, It is preferable that the spectrum of the light emitted from the light emitting element is in the visible light region. A light-emitting element having two or more peaks within a wavelength range (e.g., 350 nm to 750 nm) It is preferable to apply the above-mentioned method. Also, the emission spectrum of the material having a peak in the yellow wavelength region is preferably a material that also has spectral components in the green and red wavelength regions.

[0241] The EL layer is made up of a light-emitting layer containing a light-emitting material that emits one color and a light-emitting layer containing a light-emitting material that emits another color. For example, a plurality of light-emitting layers in the EL layer are preferably laminated. The layers may be stacked in contact with each other or separated by an area that does not contain any luminescent material. For example, a fluorescent-emitting layer or a phosphorescent-emitting layer may be laminated between the fluorescent-emitting layer and the phosphorescent-emitting layer. The phosphorescent layer contains the same materials (e.g., host material, assist material) as the phosphorescent layer, and both of the emitting layers A region that does not contain any optical material may be provided. This makes it easier to manufacture the light-emitting element. In addition, the driving voltage is reduced.

[0242] The light-emitting element may be a single element having one EL layer, or a light-emitting element having multiple EL layers. and a charge generating layer interposed therebetween to form a tandem element.

[0243] The conductive film that transmits visible light is, for example, indium oxide, indium tin oxide, indium It can be formed using zinc oxide, zinc oxide, zinc oxide doped with gallium, etc. In addition, gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum Metallic materials such as iron, cobalt, copper, palladium, or titanium, including these metallic materials Alloys and nitrides of these metal materials (e.g., titanium nitride) also have a degree of translucency. In addition, a laminated film of the above materials can be used as a conductive layer. For example, a laminated film of an alloy of silver and magnesium and indium tin oxide can be used. The use of such a material is preferable because it can increase the electrical conductivity. Graphene, etc. may also be used. stomach.

[0244] The conductive film that reflects visible light is made of, for example, aluminum, gold, platinum, silver, nickel, tungsten, etc. Metallic materials such as stainless steel, chromium, molybdenum, iron, cobalt, copper, or palladium, In addition, the above-mentioned metal materials and alloys may be used. In addition, titanium, nickel, neodymium, germanium, etc. may be added. Alternatively, an alloy containing aluminum (aluminum alloy) and neodymium may be used. Also, an alloy containing copper, palladium, magnesium, and silver may be used. Gold is preferred because of its high heat resistance. By laminating a metal film or a metal oxide film in contact with the metal, oxidation can be suppressed. Examples of materials for such metal films and metal oxide films include titanium and titanium oxide. In addition, the conductive film that transmits visible light may be laminated with a film made of a metal material. For example, silver and indium tin oxide laminated film, and silver-magnesium alloy and indium tin oxide laminated film etc. can be used.

[0245] The electrodes may be formed by vapor deposition or sputtering. Using a discharge method such as the ink jet method, a printing method such as the screen printing method, or a plating method It can be formed.

[0246] In addition, the above-mentioned light-emitting layer, the substance having a high hole-injecting property, the substance having a high hole-transporting property, the The layer including a substance having a high electron transporting property, a substance having a high electron injecting property, a bipolar substance, etc. They are inorganic compounds such as quantum dots and polymer compounds (oligomers, dendrimers, polymers, etc.) For example, by using quantum dots in the light-emitting layer, It can also function as a

[0247] The quantum dot materials include colloidal quantum dot materials, alloy quantum dot materials, Core-shell type quantum dot materials, core type quantum dot materials, etc. can be used. , materials containing elements from groups 12 and 16, 13 and 15, or 14 and 16 Alternatively, cadmium, selenium, zinc, sulfur, phosphorus, indium, tellurium, Quantum dot materials containing elements such as lead, gallium, arsenic, and aluminum may also be used.

[0248] [Adhesive layer] The adhesive layer may be a light-curing adhesive such as an ultraviolet-curing adhesive, a reaction-curing adhesive, or a heat-curing adhesive. Various curing adhesives such as viscoelastic adhesives, anaerobic adhesives, etc. can be used. Epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, E VA (ethylene vinyl acetate) resin, etc. In particular, the moisture permeability of epoxy resin, etc. A material with low adhesion is preferable. Two-part mixed resin may also be used. It may be used.

[0249] The resin may contain a desiccant. For example, an oxide of an alkaline earth metal (an acid The material used is one that adsorbs moisture by chemical adsorption, such as calcium chloride or barium oxide. Alternatively, materials such as zeolite and silica gel can absorb water by physical adsorption. If a desiccant is included, impurities such as moisture may enter the element. This is preferable because it can suppress the occurrence of the problem of the noise and improve the reliability of the display panel.

[0250] In addition, by mixing a filler with a high refractive index or a light scattering material into the resin, it is possible to improve the light extraction efficiency. For example, titanium oxide, barium oxide, zeolite, and di Ruthenium, etc. can be used.

[0251] [Connection Layer] The connection layer is made of anisotropic conductive film (ACF). conductive film) and anisotropic conductive paste (ACP) Conductive Paste) can be used.

[0252] [Colored layer] Materials that can be used for the coloring layer include metal materials, resin materials, pigments, and dyes. Examples of such materials include resin materials.

[0253] [Light blocking layer] Materials that can be used for the light-shielding layer include carbon black, titanium black, Examples of the material include a metal, a metal oxide, and a composite oxide including a solid solution of a plurality of metal oxides. The film may be a film containing a resin material, or may be a thin film of an inorganic material such as a metal. In addition, the light-shielding layer may be a laminated film of a film containing the material of the colored layer. A film containing a material for a colored layer that transmits light and a material for a colored layer that transmits light of another color By using the same material for the colored layer and the light-shielding layer, a laminated structure with a film containing This is preferable because it allows the equipment to be standardized and the process to be simplified.

[0254] This embodiment may be combined, at least in part, with other embodiments described in this specification. It can be implemented in combination.

[0255] (Embodiment 4) Examples of electronic devices that can use the display device according to one embodiment of the present invention include display devices, personal computers, image storage devices or image reproducing devices equipped with recording media, mobile phones, Game consoles including those with a handheld type, portable data terminals, e-book terminals, video cameras, digital still cameras Cameras such as DSLRs, goggle-type displays (head-mounted displays), navigation systems Audio playback devices (car audio, digital audio players, etc.), Copiers, fax machines, printers, multifunction printers, automated teller machines (ATMs), Examples of such electronic devices include vending machines. Specific examples of such electronic devices are shown in Figure 20.

[0256] FIG. 20A shows a video camera, which includes a first housing 971, a second housing 972, and a display unit 973. The operation key 974, the lens 975, the connection part 976, etc. The lens 975 is provided in the first housing 971, and the display unit 973 is provided in the second housing 972. The display device of one embodiment of the present invention is provided in the display portion 973 of the video camera. This makes it possible to improve visibility outdoors and reduce power consumption.

[0257] FIG. 20B shows a portable game machine, which includes a housing 901, a housing 902, a display portion 903, and a display 904, microphone 905, speaker 906, operation keys 907, stylus 908, camera 909, etc. The portable game machine shown in FIG. and a display unit 904, the number of display units that the portable game machine has is not limited to this. The display unit 903 in the portable game machine is provided with the display device according to one embodiment of the present invention. This makes it possible to improve visibility outdoors and reduce power consumption.

[0258] FIG. 20C shows a digital camera, which includes a housing 961, a shutter button 962, a microphone, and the like. 963, a speaker 967, a display unit 965, and operation keys 966. By providing the display device of one embodiment of the present invention to the display portion 965 of the It is possible to improve the image quality and reduce power consumption.

[0259] FIG. 20D shows a wristwatch-type information terminal, which includes a housing 931, a display unit 932, and a wristband. The display unit 932 includes a display 933, an operation button 935, a crown 936, a camera 939, etc. The display unit 932 of the information terminal may be a touch panel. By providing a display device with this function, visibility can be improved even outdoors. This allows for improved design.

[0260] FIG. 20E shows an example of a mobile phone, which includes a housing 951, a display unit 952, and an operation button 953. , an external connection port 954, a speaker 955, a microphone 956, a camera 957, etc. The mobile phone has a touch sensor on the display unit 952. All operations, such as inputting, can be performed by touching the display unit 952 with a finger or a stylus. The display device according to one embodiment of the present invention is provided in the display portion 952 of the mobile phone. This improves visibility even outdoors. The design can be improved.

[0261] FIG. 20F shows a portable data terminal, which includes a housing 911, a display unit 912, a camera 919, etc. The display unit 912 has a touch panel function that allows input and output of information. By providing the display device of one embodiment of the present invention to the display unit 912 of the portable data terminal, This improves visibility even outdoors. In addition, the frame can be narrowed, making it possible to reduce the size. It is possible.

[0262] This embodiment may be combined, at least in part, with other embodiments described in this specification. It can be implemented in combination. [Explanation of symbols]

[0263] B1 light B2 light C1 Capacitive element C2 Capacitor element C11 Capacitor element G1 Wiring G2 Wiring G3 Wiring GL_n Gate line GL_1 Gate line GL_4 Gate line GLA_n Gate line GLA_1 Gate line GLB_s Gate line GLB_1 Gate line M1 Transistor M2 Transistor M3 Transistor M11 Transistor M13 Transistor M14 Transistor R1 Light R2 light S1 Wiring S2 wiring S3 Wiring SR_n Pulse output circuit SR_1 Pulse output circuit SW1 Switch SW2 switch T1 time T2 time T3 time VCOM1 wiring VCOM2 wiring 11 Display device 25 Planarization film 45 pixels 46 pixels 46B Display element 46G display element 46R Display element 47 pixels 47B Display element 47G display element 47R Display element 55 light 61 Transistor 62 Semiconductor layer 63 Gate electrode 64 Source electrode 65 Drain electrode 66 Connection 69 Gate insulating film 70 Buffer circuit 71a Transistor 71b Transistor 72 FPC 72a Semiconductor layer 72b Semiconductor layer 73a Gate electrode 73b Gate electrode 74a Drain electrode 74b Drain electrode 75a Source electrode 75b Source electrode 77 Conductive Layer 79a Gate insulating film 79b Gate insulating film 91 Drive circuit 91_n Pulse output circuit 91_s Pulse output circuit 91_1 Pulse output circuit 91_4 Pulse output circuit 91A Drive Circuit 91B Drive circuit 92 Display section 93 Drive circuit 94 Pixel circuit 94B Circuit 100 Display Panel 101 layers 102 layers 102a layer 102b layer 103 layers 112 Liquid crystal 113 Conductive Layer 117 Insulating Layer 121 Insulating layer 130 Polarizing Plate 131 Colored layer 132 Light blocking layer 133a Alignment film 133b Alignment film 134 Colored layer 141 Adhesive layer 142 Adhesive layer 191 Conductive Layer 192 EL layer 193a conductive layer 193b Conductive layer 201a Transistor 201b Transistor 204 Connection 205 Transistor 206 Transistor 207 Transistor 208 Connection 211a Insulating layer 211b Insulating layer 212 Insulating layer 212a Insulating layer 212b Insulating layer 213 Insulating Layer 213a Insulating layer 213b Insulating layer 214 Insulating layer 214a Insulating layer 214b Insulating layer 215 Insulating Layer 216 Insulating Layer 217 Insulating Layer 218 Insulating Layer 220 Insulating layer 221 Conductive Layer 222 Conductive Layer 231 Semiconductor Layer 242 Connection Layer 243 Connectors 251 Aperture 252 Connection 300 Display Panel 311 Electrode 311a conductive layer 311b Conductive layer 340 Liquid crystal element 351 Substrate 360 Light emitting element 360b Light emitting element 360g Light emitting element 360r Light emitting element 360w light emitting element 361 Substrate 362 Display section 364 circuits 365 Wiring 372 FPC 373 IC 400 display device 401 Conductive layer 402 Conductive layer 403 Semiconductor Layer 404 Opening 405 Opening 406A opening 406B opening 410 pixels 451 Aperture 901 Case 902 Case 903 Display section 904 Display section 905 Mike 906 Speaker 907 Operation Key 908 Stylus 909 Camera 911 Case 912 Display section 919 Camera 931 Case 932 Display section 933 Wristband 935 Button 936 Crown 939 Camera 951 Case 952 Display section 953 Operation button 954 External connection port 955 Speaker 956 Mike 957 Camera 961 Case 962 Shutter button 963 Mike 965 Display section 967 Speaker 971 Case 972 Case 973 Display section 974 Operation Key 975 Lens 976 Connection

Claims

1. A display unit is provided on a substrate. The display unit is a display device having a plurality of pixels each having a light-emitting element, The display unit is a first semiconductor layer having a channel formation region of a first transistor; a first insulating layer having a region overlying the first semiconductor layer; a first conductive layer having a region located on the first insulating layer and functioning as a gate electrode of a second transistor; a second insulating layer having a region located on the first conductive layer and functioning as a gate insulating layer for the second transistor; a second semiconductor layer having a region located on the second insulating layer and having a channel formation region of the second transistor; a second conductive layer having a region in contact with a top surface of the second semiconductor layer and functioning as one of a source electrode and a drain electrode of the second transistor; a third conductive layer having a region in contact with a top surface of the second semiconductor layer and functioning as the other of the source electrode and the drain electrode of the second transistor; a third insulating layer having a region overlying the second conductive layer and a region overlying the third conductive layer; the first conductive layer is disposed in a layer different from a gate electrode of the first transistor; the light emitting element has a region located on the third insulating layer, one of the third conductive layers has a region that functions as one electrode of a capacitor element; The substrate is flexible, the second semiconductor layer does not have an area overlapping with the first semiconductor layer, The third conductive layer has a region overlapping with the first semiconductor layer.

2. A display unit is provided on a substrate. The display unit is a display device having a plurality of pixels each having a light-emitting element, The display unit is a first semiconductor layer having a channel formation region of a first transistor; a first insulating layer having a region overlying the first semiconductor layer; a first conductive layer having a region located on the first insulating layer and functioning as a gate electrode of a second transistor; a second insulating layer having a region located on the first conductive layer and functioning as a gate insulating layer for the second transistor; a second semiconductor layer having a region located on the second insulating layer and having a channel formation region of the second transistor; a second conductive layer having a region in contact with a top surface of the second semiconductor layer and functioning as one of a source electrode and a drain electrode of the second transistor; a third conductive layer having a region in contact with a top surface of the second semiconductor layer and functioning as the other of the source electrode and the drain electrode of the second transistor; a third insulating layer having a region overlying the second conductive layer and a region overlying the third conductive layer; the first conductive layer is disposed in a layer different from a gate electrode of the first transistor; the light emitting element has a region located on the third insulating layer, one of the third conductive layers has a region that functions as one electrode of a capacitor element; The substrate is flexible, the second semiconductor layer does not have an area overlapping with the first semiconductor layer, the third conductive layer has a region overlapping with a channel formation region of the first transistor.

3. In claim 1 or 2, The second semiconductor layer comprises indium, gallium, and zinc.

4. In any one of claims 1 to 3, The display device, wherein the light-emitting element has a phosphorescent light-emitting layer.

5. In claim 4, The display device, wherein the phosphorescent light-emitting layer comprises a phosphorescent material and a host material.

Images