JP7842277B2 - Semiconductor equipment - Google Patents

Description

One aspect of the present invention relates to a semiconductor device. Another aspect of the present invention relates to a display device, a display module, and an electronic device.

The technology of constructing transistors (also called field-effect transistors (FETs) or thin-film transistors (TFTs)) using semiconductor layers formed on substrates with insulating surfaces is attracting attention. These transistors are widely applied in electronic devices such as integrated circuits (ICs) and image display devices (display devices). While semiconductor materials such as silicon are widely known as semiconductor layers applicable to transistors, the technology of using oxide semiconductors as other materials is also attracting attention.

For example, a technique for fabricating transistors using amorphous oxides containing In, Zn, Ga, Sn, etc., as oxide semiconductors has been disclosed (see Patent Document 1). Also, a technique for fabricating transistors with oxide semiconductor layers having a self-aligning top gate structure has been disclosed (see Patent Document 2). Furthermore, a technique for fabricating transistors with a structure in which an oxide semiconductor layer in which a channel is formed by the electric fields of the upper and lower gate electrodes is electrically surrounded has been disclosed in order to increase the field-effect mobility (see Patent Document 3).

Furthermore, a technique has been disclosed for fabricating transistors with enhanced electrical reliability, such as smaller threshold voltage shifts during long-term use, by using an insulating layer that releases oxygen upon heating as the underlying insulating layer for the oxide semiconductor layer that forms the channel, thereby reducing oxygen vacancies in the oxide semiconductor layer (see Patent Document 4).

Japanese Patent Publication No. 2006-165529 Japanese Patent Publication No. 2009-278115 Japanese Patent Publication No. 2014-241404 Japanese Patent Publication No. 2012-009836

Transistors with oxide semiconductor layers are expected to have applications in display devices. Capacitive elements that make up the pixel circuits of display devices have a large capacitance (hereinafter referred to as capacitance) in a small area.
This is required. When the capacity for holding the data voltage becomes small, charge injection and feedthrough occur.
This is to avoid the problem of the influence of gh) becoming too great.

To obtain a large capacitance in a small area, a capacitive element is formed by sandwiching a thin gate insulating film between the gate electrode and a semiconductor layer; this is known as MOS (Metal-Oxide-Semiconductor) capacitor.
uctor) capacity (or MIS (Metal-Isulator-Semicond
Capacitor is effective. However, MOS capacitance is small when holding low voltages near 0V, making it difficult to hold low-gradation data voltages.

One aspect of the present invention aims to provide a display device or the like with a novel configuration that can obtain a large capacity even with a small area. Alternatively, one aspect of the present invention aims to provide a display device or the like with a novel configuration that can obtain a large capacity even when performing grayscale display while maintaining a low voltage.

It should be noted that the problems addressed by one aspect of the present invention are not limited to those listed above. The problems listed above do not preclude the existence of other problems. These other problems are those not mentioned in this section, which are described below. Those not mentioned in this section can be derived from the description in the specification or drawings, etc., by those skilled in the art, and can be appropriately extracted from these descriptions. It should be noted that one aspect of the present invention solves at least one of the problems listed above and/or other problems.

One aspect of the present invention provides a pixel having a first wiring, a first transistor, a first capacitive element, and a light-emitting element, wherein the first wiring functions as a current supply line for supplying current to the light-emitting element, and the first transistor has a first gate electrode, a first insulating layer on the first gate electrode, an oxide semiconductor layer on the first insulating layer, a source electrode and a drain electrode on the oxide semiconductor layer, and a second insulating layer on the source electrode and the drain electrode and the oxide semiconductor layer.
The first capacitive element has a first electrode and a second gate electrode on a second insulating layer.
The display device comprises an electrode and an insulating layer provided in the same layer as the second insulating layer between the first electrode and the second electrode, wherein the first electrode has a conductive layer provided in the same layer as the second gate electrode, and the second electrode has an oxide semiconductor layer provided in the same layer as the oxide semiconductor layer, and the first capacitive element has a third electrode layer electrically connected to the first wiring via an insulating layer provided in the same layer as the first insulating layer, and the third electrode layer is provided in the same layer as the first gate electrode.

In one embodiment of the present invention, the second gate electrode and the first electrode are oxygen, In, and Z
A display device having n and M (where M is Al, Ga, Y, or Sn) is preferred.

In one embodiment of the present invention, the second gate electrode and the first electrode are preferably made of an oxide semiconductor and the second electrode, respectively, and are used in a display device with a higher carrier density than the first electrode.

In one embodiment of the present invention, a display device is preferred in which the thickness of the second insulating layer is greater than the thickness of the first insulating layer.

In one embodiment of the present invention, the pixel has a second transistor, a second capacitive element, and a liquid crystal element, the liquid crystal element has a reflective electrode with an aperture, and the light-emitting region of the light-emitting element is
A display device having an area that overlaps with the area where an opening is provided is preferred.

Further embodiments of the present invention are described in the following descriptions of embodiments and in the drawings.

One aspect of the present invention can provide a display device with a novel configuration that can obtain a large capacity even with a small area. Alternatively, one aspect of the present invention can provide a display device with a novel configuration that can obtain a large capacity even when performing grayscale display while maintaining a low voltage.

A circuit diagram and timing chart illustrating a display device according to one embodiment of the present invention. A cross-sectional view and graph illustrating a display device according to one embodiment of the present invention. A top view and a cross-sectional view illustrating a display device according to one embodiment of the present invention. A cross-sectional view and a circuit diagram illustrating a display device according to one embodiment of the present invention. A circuit diagram illustrating a display device according to one embodiment of the present invention. A circuit diagram illustrating a display device according to one embodiment of the present invention. A top view illustrating a display device according to one aspect of the present invention. A schematic diagram illustrating a display device according to one embodiment of the present invention. A cross-sectional view illustrating a display device according to one embodiment of the present invention. A circuit diagram illustrating a display device according to one embodiment of the present invention. A circuit diagram illustrating a display device according to one embodiment of the present invention. A circuit diagram and a schematic cross-sectional view illustrating a display device according to one embodiment of the present invention. An example of the configuration of a display device according to an embodiment. An example of the configuration of a display device according to an embodiment. An example of the configuration of a display device according to an embodiment. An example of a touch panel configuration according to an embodiment. A diagram illustrating a method for manufacturing a display device according to an embodiment. A diagram illustrating a method for manufacturing a display device according to an embodiment. A diagram illustrating a method for manufacturing a display device according to an embodiment. A diagram illustrating a method for manufacturing a display device according to an embodiment. A diagram illustrating a method for manufacturing a display device according to an embodiment. An electronic device according to an embodiment. An electronic device according to an embodiment. An electronic device according to an embodiment. An electronic device according to an embodiment. An electronic device according to an embodiment.

Embodiments will be described in detail with reference to the drawings. However, it will be readily apparent to those skilled in the art that the present invention is not limited to the following description, and that its form and details can be modified in various ways without departing from the spirit and scope of the present invention. Accordingly, the present invention shall not be construed as being limited to the descriptions of the embodiments shown below.

In the configuration of the invention described below, the same reference numerals are used in common across different drawings for parts that are the same or have similar functions, and repeated explanations are omitted. Also, when referring to similar functions, the hatching patterns are the same, and reference numerals may not be assigned.

In each figure described herein, the size, layer thickness, or area of each component is as follows:
It may be exaggerated for clarity; therefore, it is not necessarily limited to that scale.

Furthermore, ordinal numbers such as "the first,""thesecond," etc., used in this specification are added to avoid confusion of constituent elements and do not imply any numerical limitation.

A transistor is a type of semiconductor device that can perform functions such as amplifying current and voltage, and switching operations that control conduction or non-conductivity. In this specification, the term "transistor" refers to an IGFET (Insulated Gate Field Effect Transistor).
(Istor) and Thin Film Transistor (TFT)
) includes.

Furthermore, the functions of "source" and "drain" may be reversed when transistors of different polarities are used or when the direction of current changes during circuit operation. For this reason, in this specification, the terms "source" and "drain" may be used interchangeably.

(Embodiment 1)
This embodiment describes an example of the configuration of a display device according to one aspect of the present invention.

[Example of circuit diagram configuration]
Figure 1(A) is a circuit diagram of the pixels in the display device.

Each pixel PIX comprises transistors M1, M2, and M3, a capacitive element MC, and a light-emitting element EL. Each pixel PIX is connected to the scan line GL, signal line SL, current supply line ANODE, wiring V0, and common wiring CATHODE. Each pixel PIX corresponds to a sub-pixel of a pixel that performs color display. Note that transistors M1, M2, and M3...
The following explanation assumes an n-channel transistor, but a p-channel transistor may also be used.

The scan line GL is the wiring that supplies the scan signal to the pixels. The scan signal is a signal that controls the conduction state of the supplied transistor. The signal line SL is the wiring that supplies the data voltage to the pixels according to the image data. The current supply line ANODE and the common wiring CATHODE are the wirings that supply current to the light-emitting element EL. Wiring V0 is the wiring to which a constant voltage is supplied.

A capacitive transistor (MC) is a transistor composed of gate electrodes located above and below an oxide semiconductor layer. The gate electrode located below the oxide semiconductor layer of the MC, made of a metallic material, is called the first gate electrode (also called the bottom gate electrode). The gate electrode located above the oxide semiconductor layer, made of a metal oxide material, is called the second gate electrode (also called the top gate electrode). A metal oxide material is a material containing a metallic element and oxygen.

The capacitive element MC is a so-called MOS capacitor, composed of a second gate electrode, an insulating layer provided in contact with the second electrode, and an oxide semiconductor layer. The second gate electrode, which is one electrode of the capacitive element MC, is connected to the gate electrode of transistor M3. The source electrode and drain electrode, which are the other electrodes of the capacitive element MC, are connected to the source electrode of transistor M3. The first gate electrode is connected to the current supply line ANODE, in other words, to the other side of the source or drain of transistor M3.

Although transistors M1, M2, and M3 are shown as single-gate transistors, they may also be transistors with gate electrodes provided above and below the oxide semiconductor layer, similar to the capacitive element MC. Examples of configurations applicable to the capacitive element MC, transistors M1, M2, and M3 will be described later.

The gate electrode of transistor M1 is connected to the scan line GL. Either the source or the drain of transistor M1 is connected to the signal line SL. The other source or drain of transistor M1 is connected to the gate electrode of transistor M3, as well as one electrode of the capacitive element MC.

The gate electrode of transistor M2 is connected to the scan line GL. One of the sources or drains of transistor M2 is connected to the wiring V0. The other source or drain of transistor M2 is connected to one of the sources or drains of transistor M3, the other electrode of the capacitive element MC, and one electrode of the light-emitting element EL.

The gate electrode of transistor M3 is connected to the other side of the source or drain of transistor M1.
It is connected to one electrode of the capacitive element MC. One source or drain of transistor M3 is connected to the other source or drain of transistor M2, the other electrode of the capacitive element MC, and one electrode of the light-emitting element EL. The other source or drain of transistor M3 is connected to the current supply line ANODE.

One electrode of the light-emitting element EL is connected to the other electrode of either the source or drain of transistor M2, one electrode of either the source or drain of transistor M3, and the other electrode of the capacitive element MC. The other electrode of the light-emitting element EL is connected to the common wiring CATHODE.

Figure 1(B) shows a timing chart to illustrate the simple operation of Figure 1(A). Figure 1(B) illustrates the scan selection period (P _SCAN ) on the m-th scan line GL_m. It also illustrates the voltage V applied to the current supply line ANODE, the voltage of _ANODE and wiring V0, and the image signal on the signal line SL.

As shown in Figure 1(B), during one scan selection period, the image signal of signal line SL is (m-1)
The signal switches from row 1, DATA_m-1 to row m, DATA_m. During this time, the voltage V supplied to the current supply line _ANODE is supplied to the current-emitting element EL.
The voltage should be higher than the voltage at O.

In the configurations shown in Figures 1(A) and (B), the first gate electrode can be formed from a conductive layer made of a metal material, and the second gate electrode can be formed from a conductive layer made of a metal oxide material. The conductive layer made of a metal oxide material can supply oxygen to the insulating layer, which is the film-forming surface, during film formation. The oxygen supplied to the insulating layer can be released into the semiconductor layer having an oxide semiconductor by heating. Therefore, by using a conductive layer made of a metal oxide material for the second gate electrode, the reliability of transistors M1, M2, and M3 can be improved.

In the configurations shown in Figures 1(A) and (B), as described above, the threshold voltage shift can be reduced by decreasing the reliability of transistors M1, M2, and M3, i.e., by reducing oxygen vacancies in the semiconductor layer having an oxide semiconductor. On the other hand, when transistors function as MOS capacitors, if the threshold voltage of the transistor is near 0V, the capacitance is small when holding low voltages, making it difficult to maintain low-gradation data voltages.

Figure 2(A) shows the voltages of the first gate electrode, second gate electrode, and source and drain electrodes of the transistor functioning as a MOS capacitor, as shown in the circuit diagram, as "Vb,""Vg," and "Vs," respectively. Figure 2(B) shows the voltage between the second gate electrode and the source electrode, "Vg - Vs," on the horizontal axis, and the capacitance element MC, which is a MOS capacitor, on the horizontal axis.
This is a graph with capacity on the vertical axis.

As shown in Figure 2(B), a transistor whose threshold voltage is near 0V is M
When using OS capacitance, if the voltage Vb applied to the first gate electrode and the voltage Vb applied to the source electrode are at the same potential (Vb - Vs = 0), applying a low voltage to the second gate electrode results in a small capacitance being held.

On the other hand, as shown in Figure 2(B), even when a transistor with a threshold voltage near 0V is used as a MOS capacitor, if the Vb supplied to the first gate electrode is made larger than the Vb supplied to the source electrode (Vb - Vs > 0), the threshold voltage of the transistor can be shifted negatively. Specifically, as shown in Figures 1(A) and (B), the wiring VO
A voltage V applied to the current supply line ANODE, which is higher than the voltage of the first gate electrode, is used to make _ANODE function as Vb applied to the first gate electrode. Therefore, even when a low voltage is applied to the second gate electrode, the capacitance held can be increased.

Furthermore, in the configurations shown in Figures 1(A) and 1(B), the insulating layer between the second gate electrode and the oxide semiconductor layer is thinner than the insulating layer between the first gate electrode and the oxide semiconductor layer because heating releases oxygen, thereby reducing oxygen vacancies in the oxide semiconductor layer. As a result, the capacitive element MC can achieve a large capacitance in a small area.

In Figure 1(A), transistors M1, M2, and M3 are described as having a single-gate structure. However, as shown in pixel PIX_A in Figure 3(A), they may also have a first gate electrode and a second gate electrode, with their gate electrodes connected to each other. In this configuration, transistors M1, M2, and M3 are transistors with gate electrodes provided above and below the oxide semiconductor layer, similar to the capacitive element MC.

In Figure 1(A), the first gate electrode of the capacitive element MC is connected to the current supply line ANODE. However, other configurations are acceptable as long as the wiring can provide a voltage that can negatively shift the threshold voltage of the transistor. For example, as shown in pixel PIX_B in Figure 3(B), the first gate electrode can be connected to a wiring V1 that is different from the current supply line ANODE. It is preferable to apply a higher voltage to wiring V1 than to wiring V0, similar to the current supply line ANODE.

In Figure 2(A), transistors M1, M2, and M3 are configured to have two gate electrodes connected, but they may also be configured to have separate signals applied to the first and second gate electrodes. For example, as shown in pixel PIX_C in Figure 4(A), the first gate electrodes of transistors M1 and M2 may be connected to the scan line GL, and the second gate electrodes may be connected to the wiring V0. With this configuration, transistors M1 and M2 can have the first gate electrode connected to the second gate electrode.
A configuration can be adopted in which a scan line GL made of a metallic material is placed in the same layer as the gate electrode. Therefore, even if a configuration is adopted in which the first gate electrode is formed of a conductive layer made of a metallic material and the second gate electrode is formed of a conductive layer made of a metal oxide material, the problem of high resistance of the scan line GL can be avoided. In addition, the manufacturing cost of providing extra wiring made of metallic material to lower the resistance of the scan line GL can be reduced.

Note that Figure 2(A) shows a configuration in which the current supply line ANODE is arranged parallel to the signal line SL and wiring V0, but other configurations are also possible. For example, the pixel PI shown in Figure 4(B)
As shown in X_D, it is also possible to configure the current supply line ANODE to be positioned parallel to the scan line GL.

[Example of transistor configuration]
Here, examples of transistor or MOS capacitance configurations applicable to transistors M1, M2, M3, and the capacitance element MC will be explained using Figures 5(A), (B), and (C).

Figures 5(A), 5(B), and 5(C) show an example of a semiconductor device having a transistor.
The transistors shown in (A), (B), and (C) have a structure in which gate electrodes are provided above and below the semiconductor layer.

Figure 5(A) is a top view of transistor 100, Figure 5(B) is a cross-sectional view between the dashed lines X1 and X2 in Figure 5(A), and Figure 5(C) is a cross-sectional view between the dashed lines Y1 and Y2 in Figure 5(A). Note that in Figure 5(A), components such as the insulating layer 110 are omitted for clarity. Note that in the top view of the transistor, subsequent drawings will also refer to Figure 5(
Similar to A), some components may be omitted in the illustration. Also, the dashed line X1-X
The two directions are sometimes referred to as the channel length (L) direction, and the direction of the dashed line Y1-Y2 is sometimes referred to as the channel width (W) direction.

The transistor 100 shown in Figures 5(A), (B), and (C) consists of a conductive layer 106 formed on a substrate 102, an insulating layer 104 on the conductive layer 106, and an oxide semiconductor layer 108 on the insulating layer 104.
And, an insulating layer 110 on the oxide semiconductor layer 108, a metal oxide layer 112 on the insulating layer 110, an insulating layer 104, an oxide semiconductor layer 108, and an insulating layer 116 on the metal oxide layer 112,
It has a channel region 108i in contact with the insulating layer 110.
The source region 108s is in contact with the insulating layer 116, and the drain region 1 is in contact with the insulating layer 116.
It has 08d and .

Furthermore, the transistor 100 may have a conductive layer 120a that is electrically connected to the source region 108s through an opening 141a provided in the insulating layer 116, and a conductive layer 120b that is electrically connected to the drain region 108d through an opening 141b provided in the insulating layer 116.

Furthermore, the conductive layer 106 functions as a first gate electrode and is made of a metallic material. The metal oxide layer 112 functions as a second gate electrode and is made of a metallic oxide material. In addition, the insulating layer 104 functions as a first gate insulating layer and is made of a metallic oxide material.
It functions as a second gate insulating layer.

Furthermore, the insulating layer 116 contains either nitrogen or hydrogen, or both.
By configuring 16 to have either nitrogen or hydrogen, or both, it is possible to supply either nitrogen or hydrogen, or both, to the oxide semiconductor layer 108 and the metal oxide layer 112.

Examples of insulating layers 116 include nitride insulating layers. These nitride insulating layers can be formed using silicon nitride, silicon oxide nitride, aluminum nitride, aluminum oxide nitride, etc. The hydrogen concentration in the insulating layer 116 is 1 × ^10²² atoms.
It is preferable that the concentration is ³ or more per cm.

Furthermore, the metal oxide layer 112 has the function of supplying oxygen to the insulating layer 110. Because the metal oxide layer 112 has the function of supplying oxygen to the insulating layer 110, it becomes possible to include excess oxygen in the insulating layer 110. Since the insulating layer 110 has an excess oxygen region, this excess oxygen can be supplied to the oxide semiconductor layer 108, more specifically to the channel region 108i. Therefore, a highly reliable semiconductor device can be provided.

The insulating layer 110 can be formed by a single layer or a laminate of oxide insulating layers or nitride insulating layers. Examples of insulating layers 110 include silicon oxide, silicon oxide nitride, silicon oxide nitride, silicon nitride, aluminum oxide, hafnium oxide, gallium oxide, or G
α-Zn oxide or the like can be used, and it can be provided in a single layer or in a multilayer structure.

By configuring the insulating layer 110 formed above the oxide semiconductor layer 108 to have excess oxygen, it becomes possible to selectively supply excess oxygen only to the channel region 108i.
Alternatively, after supplying excess oxygen to the channel region 108i, the source region 108s, and the drain region 108d, the carrier density in the source region 108s and the drain region 108d can be selectively increased.

The metal oxide layer 112 has a higher carrier density when nitrogen, hydrogen, or both are supplied from the insulating layer 116. In other words, the metal oxide layer 112 also functions as an oxide conductor (OC). Therefore, the metal oxide layer 112 has a higher carrier density than the oxide semiconductor layer 108.

The source region 108s and drain region 108d of the oxide semiconductor layer 108, and the metal oxide layer 112, may each contain elements that form oxygen vacancies. Typical examples of elements that form oxygen vacancies include hydrogen, boron, carbon, nitrogen, fluorine, phosphorus, sulfur, chlorine, and noble gases. Typical examples of noble gas elements include helium.
Examples include neon, argon, krypton, and xenon.

When impurity elements are added to an oxide semiconductor layer, the bond between the metal elements and oxygen in the oxide semiconductor layer is broken, forming an oxygen vacancy. Alternatively, when impurity elements are added to an oxide semiconductor layer, the oxygen that was bonded to the metal elements in the oxide semiconductor layer bonds with the impurity element, causing oxygen to be released from the metal elements and forming an oxygen vacancy. As a result, the carrier density in the oxide semiconductor layer increases, and its conductivity improves.

In the transistor 100, it is preferable that the side edge of the insulating layer 110 and the side edge of the metal oxide layer 112 are aligned in a region. In other words, in the transistor 100, the upper end of the insulating layer 110 and the lower end of the metal oxide layer 112 are roughly aligned. For example, the above structure can be achieved by processing the insulating layer 110 using the metal oxide layer 112 as a mask.

The oxide semiconductor layer 108 and the metal oxide layer 112 are made of In-M-Zn oxide (where M is Al).
It is formed from an oxide semiconductor such as Ga, Y, or Sn. In addition, In-Ga oxide and In-Zn oxide may be used as the oxide semiconductor layer 108 and the metal oxide layer 112. In particular, it is preferable that the oxide semiconductor layer 108 and the metal oxide layer 112 be formed from an oxide semiconductor composed of the same constituent elements, as this can reduce manufacturing costs.

When the oxide semiconductor layer 108 and the metal oxide layer 112 are In-M-Zn oxide,
For the sputtering target used to deposit -M-Zn oxide films, it is preferable that the atomic ratio of the metal elements satisfies In ≥ M and Zn ≥ M. Such atomic ratios of metal elements in a sputtering target include In:M:Zn = 1:1:1 and In:M:Zn = 1:1.
:1.2, In:M:Zn=2:1:1.5, In:M:Zn=2:1:2.3, In:
M:Zn=2:1:3, In:M:Zn=3:1:2, In:M:Zn=4:2:4.1
In:M:Zn = 5:1:7 is preferred. Note that the oxide semiconductor layer 108 to be formed,
The atomic ratios of the metal oxide layer 112 can vary by approximately plus or minus 40% from the atomic ratio of the metal elements contained in the sputtering target. For example, if an atomic ratio of In:Ga:Zn = 4:2:4.1 is used as the sputtering target, the atomic ratio of the deposited oxide semiconductor layer may be close to In:Ga:Zn = 4:2:3.

By using an oxide semiconductor layer with a low impurity concentration and low defect level density as the channel region 108i, transistors with even better electrical properties can be fabricated.
Here, a low impurity concentration and low defect level density (few oxygen vacancies) are referred to as high-purity intrinsic or substantially high-purity intrinsic. Alternatively, it is referred to as intrinsic or substantially intrinsic. Oxide semiconductors that are high-purity intrinsic or substantially high-purity intrinsic have few carrier sources,
In some cases, the carrier density can be reduced. Therefore, transistors in which a channel region is formed in the oxide semiconductor layer tend to exhibit electrical characteristics where the threshold voltage is positive (also known as normally-off characteristics). Furthermore, oxide semiconductor layers that are high-purity intrinsic or substantially high-purity intrinsic have a low defect level density, and therefore, the trap level density may also be low.
Furthermore, oxide semiconductor layers that are high-purity intrinsic or substantially high-purity intrinsic can exhibit significantly low off-current characteristics. Therefore, transistors in which a channel region is formed in such oxide semiconductor layers may exhibit less variation in electrical characteristics and become highly reliable transistors.

On the other hand, the source region 108s, the drain region 108d, and the metal oxide layer 112 are in contact with the insulating layer 116.
When 12 comes into contact with the insulating layer 116, hydrogen and nitrogen, or either one or both, are added from the insulating layer 116 to the source region 108s, the drain region 108d, and the metal oxide layer 112, thus increasing the carrier density.

The carrier density of the oxide semiconductor layer is explained below.

Factors that affect the carrier density of an oxide semiconductor layer include oxygen vacancies (Vo) in the oxide semiconductor layer, or impurities in the oxide semiconductor layer.

When the number of oxygen vacancies in the oxide semiconductor layer increases, hydrogen atoms bond to these oxygen vacancies (this state is called _V₂O₃).
When this occurs (also known as H), the defect level density increases. Alternatively, if the amount of impurities in the oxide semiconductor layer increases, the defect level density increases due to these impurities. Therefore, by controlling the defect level density in the oxide semiconductor layer, the carrier density of the oxide semiconductor layer can be controlled.

As shown in Figure 5(C), the oxide semiconductor layer 108 is positioned opposite the conductive layer 106, which functions as the first gate electrode, and the metal oxide layer 112, which functions as the second gate electrode, and is sandwiched between the two conductive layers or oxide semiconductor layers that function as gate electrodes.

With the configuration shown in Figure 5(C), when the transistor 100 is to function as a transistor, the oxide semiconductor layer 108 contained in the transistor 100 can be electrically surrounded by the electric field caused by the scanning signal of the conductive layer 106 which functions as the first gate electrode, and the electric field caused by the constant voltage of the metal oxide layer 112 which functions as the second gate electrode.

Although not shown in Figure 5(C), the transistor 100 may have an opening in the insulating layer 110 and the insulating layer 104 for connecting the first gate electrode and the second gate electrode. With such a configuration, the oxide semiconductor layer 108 included in the transistor 100 can function as the first gate electrode, the conductive layer 106, and the second
The metal oxide layer 112, which functions as the gate electrode, can be electrically surrounded by the electric fields of both sides.

Furthermore, by using the configuration shown in Figure 5(C), when the transistor 100 functions as a MOS capacitor, a voltage that negatively shifts the threshold voltage of the transistor can be applied to the conductive layer 106, which functions as the first gate electrode. The MOS capacitor can be composed of an oxide semiconductor layer 108, an insulating layer 110, and a metal oxide layer 112, which functions as the second gate electrode.

When transistor 100 functions as a MOS capacitor, capacitance can be formed by the oxide semiconductor layer 108, insulating layer 110, and metal oxide layer 112 shown in the cross-sectional view of Figure 6(A). In other words, a MOS capacitor equivalent to the capacitance element MC in the circuit diagram of Figure 5(B) can be formed. Note that in Figures 6(A) and 6(B), "Vg", "Vs", and "V
"b" represents the corresponding voltage in the circuit diagram and cross-sectional view, similar to Figure 2(A).

In the configurations shown in Figures 6(A) and 6(B), the voltage Vg applied to the conductive layer 106 is a voltage that negatively shifts the threshold voltage of the transistor. The insulating layer 110 constitutes the MOS capacitance.
The film thickness 110t of the insulating layer 104 is smaller than the film thickness 104t of the insulating layer 104. Therefore, even when a small voltage is applied to the metal oxide layer 112 and capacitance is formed between the insulating layer 110 and the metal oxide layer 112, a high capacitance can be secured, and a large capacitance can be achieved in a small area.

[Example of configuration in the top view]
Next, Figure 7 shows an example of a top view applicable to the circuit configuration of pixel PIX_D in Figure 4(B), excluding the configuration of light-emitting elements, etc. Figure 8 illustrates how the conductive layer and semiconductor layer, etc., which are in a vertical relationship in the top view of Figure 7, are separated layer by layer and connected via apertures.
Figure 9(A) is a cross-sectional view between the dotted lines P1 and P2 in Figure 7, and Figure 9(B) is a cross-sectional view between the dotted lines Q1 and Q2 in Figure 7. Figure 10 is a circuit diagram showing multiple pixels arranged in a row, corresponding to the arrangement of transistors in the top view of Figure 7.

In the top view of Figure 7, the scan line GL, the signal line SL, the wiring V0, and the current supply line ANODE are shown.
And transistor M1, transistor M2, transistor M3, and capacitive element MC,
This is illustrated in the diagram. In the layer structure of the conductive layer, metal oxide layer, and oxide semiconductor layer, insulating layers, etc., are not shown in the diagram.

The layer structure of the conductive layer, metal oxide layer, and oxide semiconductor layer constituting each wiring etc. in Figure 7 can be understood from Figures 8 and 9. Conductive layer 151, conductive layer 152, and conductive layer 153, which function as the first gate electrode, are provided on the substrate SUB. Next, oxide semiconductor layer 161 and oxide semiconductor layer 162 are provided via insulating layer 154, which functions as the first gate insulating layer. Next, insulating layer 163, which functions as the second gate insulating layer
Through this, metal oxide layers 171, 172, and 173, which function as a second gate electrode, are provided. Next, conductive layers 181, 182, 183, 184, and 185, which function as source electrodes, drain electrodes, or various wirings of the transistor, are provided via a part of oxide semiconductor layer 161 and a part of oxide semiconductor layer 162, and an insulating layer 174 that selectively increases the carrier density in metal oxide layers 171, 172, and 173 to improve conductivity. Next, insulating layers 186, 187, and 185, which function as interlayer insulating layers
8 is provided. In addition, insulating layer 186, insulating layer 187 and insulating layer 188 have conductive layer 1
An opening 190 reaching 85 is provided. This opening 190 is for connecting to a light-emitting element that will be subsequently formed on top of the pixel electrode.

In Figures 7 and 8, the configuration marked with an "X" in a square represents an opening formed in the insulating layer. The opening connects the conductive layer, metal oxide layer, and oxide semiconductor layer of each layer, as indicated by the arrows in Figure 8. Figure 8 also shows the conductive layer 151, which forms the scanning line GL, and the current supply line A.
Conductive layer 152 which becomes NODE, conductive layer 181 which becomes wiring V0, conductive layer 1 which becomes signal line SL
Figure 82 is shown.

As can be seen from Figures 7, 8, and 9, transistors M1, M2, and M3 are configured to connect the first gate electrode to the second gate electrode. This configuration allows for an increase in the amount of current flowing through the transistors compared to when the gate electrodes are not connected to each other.

Furthermore, as can be seen from Figures 7, 8, and 9, the metal oxide layer 171, the insulating layer 163, and the oxide semiconductor layer 161 that form the capacitive element MC are located below the current supply line ANODE
The configuration includes a conductive layer 152 connected to the conductive layer 152. In this configuration, the voltage of the current supply line ANODE supplied to the conductive layer 152 shifts the threshold voltage of the transistor negatively, and since the thickness of the insulating layer 163 is smaller than the thickness of the insulating layer 154, a high capacitance can be secured. Therefore, a large capacitance can be achieved in a small area.

Note that the conductive layer 152 is connected to the current supply line ANODE, and the conductive layer 151 is the scan line GL.
It functions as a light-shielding layer by being composed of a metal material that has light-shielding and conductive properties. Therefore, it can reduce fluctuations in MOS capacitance and the electrical characteristics of transistors.

Figure 10 also shows a circuit diagram corresponding to the top view of the pixel described in Figure 7, using a 2x2 pixel PIX_
This is a circuit diagram illustrating UL, pixel PIX_UR, pixel PIX_LL, and pixel PIX_LR. In Figure 10, pixels arranged in two rows of m rows and (m+1 rows), and n columns and (n+1) columns are shown. In Figure 10, the scan line GL_m of the mth row, the scan line GL_m+1 of the (m+1)th row, the signal line SL_n of the nth column, the signal line SL_n+1 of the (n+1)th column, the wiring V0, and the current supply line ANODE are shown.

As shown in Figure 10, pixels PIX_UL and PIX_UR are configured such that the transistors M1, M2, M3 and the capacitive element MC that constitute the pixels are arranged symmetrically on either side of the wiring V0 and connected to the same wiring V0. Similarly, pixels PIX_LL and PIX_LR are configured such that the transistors M1, M2, M3 and the capacitive element MC that constitute the pixels are arranged on either side of the wiring V0.
The components are arranged symmetrically and connected to the same wiring V0.

As shown in Figure 10, pixels PIX_UL and PIX_LL are composed of transistors M1, M2, M3 and capacitive elements MC, separated by a current supply line ANODE.
The pixels are arranged symmetrically and connected to the same current supply line ANODE.
Similarly, in UR and pixel PIX_LR, the transistors M1, M2, M3 and capacitive element MC that constitute the pixel are arranged symmetrically across the current supply line ANODE, and the same current supply line AN
The configuration will connect to the ODE.

By arranging the elements and wiring as shown in Figure 10, the number of wires and other connections between pixels can be reduced. The configuration in Figure 10 is preferable because, when designing to increase the resolution of pixels, the area of the pixels can be reduced by the amount of the reduced number of wires and other connections.

[Variations]
A circuit configuration applicable to one aspect of the present invention is shown in Figure 1(A) with transistors M1 and M2
The method is not limited to pixel configurations having M3. For example, it is also applicable to pixel configurations having two or fewer transistors, as shown in Figure 11(A).

The pixel configuration of pixel PIX_E shown in Figure 11(A) includes transistor M1, transistor M3, capacitive element MC, and light-emitting element EL. In other words, it corresponds to the circuit configuration in Figure 1(A) with transistor M2 omitted.

In the configuration shown in Figure 11(A), in the capacitive element MC in which the transistor functions as a MOS capacitor, the voltage of the current supply line ANODE is applied to the first gate electrode. Then, a voltage is applied that shifts the threshold voltage of the transistor to the negative, and the capacitance at which a low voltage is applied can be increased in the MOS capacitor, which is composed of a metal oxide layer, an insulating layer, and an oxide semiconductor layer, which is the second gate electrode. The insulating layer between the second gate electrode and the oxide semiconductor layer has a thinner film thickness than the insulating layer between the first gate electrode and the oxide semiconductor layer, and can secure a higher capacitance, so a large capacitance can be achieved in a small area.

The circuit configuration applicable to one aspect of the present invention is not limited to the pixel configuration shown in Figure 11(A).
For example, this method can also be applied to pixel configurations having four or more transistors, as shown in Figure 11(B).

The pixel configuration of pixel PIX_F shown in Figure 11(A) consists of transistor M1, transistor M2, transistor M3, transistor M4, transistor M5, and a capacitive element MC
It has a light-emitting element EL. The pixel configuration also includes a signal line SL and a current supply line ANOD.
It operates using E, wiring V0, common wiring CATHODE, as well as scan lines GL1, GL2, and GL3.

In the configuration shown in Figure 11(B), in the capacitive element MC where the transistor functions as a MOS capacitor, the voltage of the current supply line ANODE is applied to the first gate electrode. Then, a voltage is applied that shifts the threshold voltage of the transistor to the negative, and the capacitance at which a low voltage is applied can be increased in the MOS capacitor, which is composed of a metal oxide layer, an insulating layer, and an oxide semiconductor layer, which is the second gate electrode. The insulating layer between the second gate electrode and the oxide semiconductor layer has a thinner film thickness than the insulating layer between the first gate electrode and the oxide semiconductor layer, and can secure a higher capacitance, so a large capacitance can be achieved in a small area.

Furthermore, the circuit configuration applicable to one aspect of the present invention is not limited to a pixel configuration having an light-emitting element, but can also be applied to a pixel having a liquid crystal element and a light-emitting element.

As an example, the pixel configuration of pixel PIX_G shown in Figure 12(A) includes transistor M1, transistor M2, transistor M3, capacitive element MC, transistor M6, capacitive element MC1, and liquid crystal element LC. Furthermore, this pixel configuration includes signal lines SL_LC.
Signal line SL_EL, current supply line ANODE, wiring V0, scan line GL_EL, scan line GL_
It operates via LC and common wiring CATHOD.

In pixel PIX_G, the video signal supplied to the gate electrode of transistor M3 is supplied from the signal line SL_EL by controlling the scan signal supplied to the scan line GL_EL.
In IX_G, the video signal applied to one electrode of the liquid crystal element LC is the scan line GL_LC.
The signal is supplied from the signal line SL_LC by controlling the scanning signal given to the pixel PIX.
For each G level, the grayscale display of the liquid crystal element (LC) and the light-emitting element (EL) can be controlled separately.
In this configuration, unlike backlight control where multiple pixels light up uniformly, the light emission of the light-emitting element (EL) can be controlled at the smallest unit, such as the pixel level, according to the image being displayed, thus suppressing unnecessary light emission. Therefore, a display device having pixels PIX_G can achieve lower power consumption.

Furthermore, in the PIX_G pixel configuration, the reflective electrodes of the liquid crystal element (LC) allow for the adjustment of the intensity of reflected light using ambient light in the liquid crystal layer, thereby enabling grayscale display.
A display device with G can improve visibility outdoors.

Furthermore, in the PIX_G pixel configuration, the intensity of light emitted by the EL light-emitting element is adjusted to perform gradation display. Therefore, a display device having PIX_G pixels can improve visibility indoors where the intensity of ambient light is low.

Furthermore, for configurations that control liquid crystal elements (LC) to display information outdoors, or control light-emitting elements (EL) to display information indoors, the display device should be equipped with a sensor capable of measuring illuminance.

Furthermore, in the configuration shown in Figure 12(A), in the capacitive elements MC and MC1, where the transistor functions as a MOS capacitor, the voltage of the current supply line ANODE is applied to the first gate electrode. By applying a voltage that shifts the threshold voltage of the transistor to the negative, the capacitance of the MOS capacitor, which is composed of a metal oxide layer, an insulating layer, and an oxide semiconductor layer, can be increased when a low voltage is applied. The insulating layer between the second gate electrode and the oxide semiconductor layer has a thinner film thickness than the insulating layer between the first gate electrode and the oxide semiconductor layer, and can secure a higher capacitance, so a large capacitance can be achieved in a small area.

The display device having pixels PIX_G shown in Figure 12(A) can be constructed by stacking light-emitting element EL and liquid crystal element LC as shown in the schematic cross-sectional view in Figure 12(B). In Figure 12(B), a layer 191 having transistors is provided between the light-emitting element EL and the liquid crystal element LC. The layer 191 having transistors includes transistor M1, transistor M2, transistor M3, capacitive element MC, transistor M6, and capacitive element MC1. The liquid crystal element LC in Figure 12(B) has an electrode 1 that can reflect ambient light (L _REF ).
It has 92. The electrode 192 has an aperture 193 for transmitting light (L _EL ) from the light-emitting element.
A system will be established.

In a display device where the schematic cross-sectional diagram shown in Figure 12(B) is applied to the pixel PIX_G described in Figure 12(A), a configuration that switches between the light-emitting element EL and the liquid crystal element LC according to the illuminance is effective. For example, when the illuminance is high, the liquid crystal element LC is driven to obtain the desired gradation, and when the illuminance is low, the light-emitting element EL is driven to obtain the desired gradation. By adopting this configuration, a display device with low power consumption and excellent visibility can be made.

This embodiment can be implemented in appropriate combination with other embodiments described herein, at least in part.

(Embodiment 2)
This embodiment describes an example of a cross-sectional configuration of a display device according to one aspect of the present invention.

[Example of display device configuration]
Figure 13 shows a schematic top view of the display device 10 described below. The display device 10 includes a pixel section 11, a scan line driving circuit 12, a signal line driving circuit 13, a terminal section 15, a plurality of wires 16a, and a plurality of wires 16b, etc.

[Cross-sectional configuration example 1]
Figure 14 is a schematic cross-sectional view of the display device 10. Figure 14 shows, for example, the cutting line A1 in Figure 13.
- This corresponds to a cross-section along A2.

The display device 10 has a configuration in which a first substrate 201 and a second substrate 202 are bonded together by an adhesive layer 220.

The first substrate 201 is provided with terminals 15, wiring 16b, transistors 252 constituting the signal line drive circuit 13, transistors 251 and 252 constituting the pixel section 11, capacitive elements 253, light-emitting elements 254, etc. Also provided on the first substrate 201 are insulating layers 211, 212, 213, 214, spacers 215, etc.

On the side of the second substrate 202 facing the first substrate 201, there is an insulating layer 221, a light-shielding layer 231, and a coloring layer 2
32. Structures 230a, 230b, etc. are provided.

A light-emitting element 254 is provided on the insulating layer 213. The light-emitting element 254 has a pixel electrode 225 that functions as a first electrode, an EL layer 222, and a second electrode 223. An optical adjustment layer 224 is provided between the pixel electrode 225 and the EL layer 222. Insulating layer 214
It is provided to cover the ends of the pixel electrode 225 and the optical adjustment layer 224.

Transistor 251 is a transistor that functions as transistor M1 or M2 as described in Figure 1(A) of the above embodiment 1. Transistor 252 is a transistor that functions as transistor M1 or M2 as described in Figure 1(A) of the above embodiment 1
This is the transistor that functions as transistor M3, as explained in Figure 1(A).

Transistors 251, 252, and 255 have a conductive layer 2 that functions as the first gate electrode.
75 and a conductive layer 272 which functions as a second gate electrode are provided. That is, the semiconductor on which the channel is formed is sandwiched between two gate electrodes. Conductive layer 275
This corresponds to the conductive layer 106 that functions as the first gate electrode as described in Figure 2 of Embodiment 1 above. The conductive layer 272 corresponds to the metal oxide layer 112 that functions as the second gate electrode as described in Figure 2 of Embodiment 1 above.

The conductive layer 275 is an electrode that can repair oxygen vacancies in the semiconductor layer 271 by releasing oxygen, thereby stabilizing the electrical characteristics of the transistor.

Furthermore, in transistors connected to light-emitting elements, such as transistor 252, it is preferable to configure them so that the same signal is applied to them, for example, by electrically connecting the two gate electrodes. Such transistors can increase their field-effect mobility compared to other transistors, and thus increase their on-current. As a result, circuits capable of high-speed operation can be fabricated.

The capacitive element 253 is composed of a part of the conductive layer 275, a part of the insulating layer 211, and a part of the semiconductor layer 271, but as shown in Figure 14, it may also be composed of a part of the conductive layer 274, a part of the insulating layer 217, and a part of the conductive layer 273.

Figure 14 shows an example where the light-emitting element 254 is a top-emission structure light-emitting element. The light emitted from the light-emitting element 254 is emitted towards the second substrate 202. With this configuration, a transistor, a capacitive element,
Since circuits, wiring, etc. can be arranged, the aperture ratio of the pixel section 11 can be increased.

On the side of the second substrate 202 facing the first substrate 201, there is a colored layer 23 that overlaps with the light-emitting element 254.
A 2 is provided. In addition, a light-shielding layer 231 may be provided in the portion where the colored layer 232 is not provided. The light-shielding layer 231 may be provided in a position that overlaps with the signal line drive circuit 13, as shown in Figure 14. In addition, a light-transmitting overcoat layer may be provided to cover the colored layer 232 and the light-shielding layer 231.

Furthermore, on the second substrate 202, on the side facing the first substrate 201, a structure 230a is provided in the region inside the adhesive layer 220, and a structure 230b is provided in the region outside the adhesive layer 220. Structures 230a and 230b have the function of suppressing the propagation of cracks that occur in the insulating layer 221 or the second substrate 202 at the edge of the second substrate 202. Figure 14 shows an example in which structures 230a and 230b are laminated structures consisting of a layer made of the same film as the light-shielding layer 231 and a layer made of the same film as the coloring layer 232a. By using a laminated structure of two or more layers in this way, the effect of suppressing crack propagation can be further enhanced. Here, structures 230 are provided on both sides of the adhesive layer 220.
Although a configuration in which structure 230a and structure 230b are provided is shown, either one may be used. Furthermore, if there is no risk of cracking (for example, if the rigidity of the second substrate 202 is high), a configuration without structures 230a and 230b may be used.

The spacer 215 is provided on the insulating layer 214. The spacer 215 functions as a gap spacer, controlling the distance between the first substrate 201 and the second substrate 202 so that it does not shrink more than necessary. Furthermore, it is preferable that the spacer 215 has a portion of its side surface at an angle between it and the surface to be formed, preferably 45 degrees or more and 120 degrees or less, more preferably 60 degrees or more and 100 degrees or less, and even more preferably 75 degrees or more and 90 degrees or less. This makes it easier to form a region on the side surface of the spacer 215 where the thickness of the EL layer 222 is thin. Therefore, it is possible to suppress the phenomenon of light emission caused by current flowing through the EL layer 222 between adjacent light-emitting elements. In particular, when the pixel portion 11 is high resolution, the distance between adjacent light-emitting elements becomes small, so providing a spacer 215 of this shape between light-emitting elements is effective. Furthermore, it is especially effective when the EL layer 222 has a layer containing a highly conductive material.

Furthermore, the spacer 215 may also function as a mask gapper to prevent damage to the surface to be formed by the shielding mask when a shielding mask is used when forming the EL layer 222 or the second electrode 223.

It is preferable that the spacer 215 is provided overlapping the wiring that intersects the scan line.

Figure 14 shows an example of a display device 10 using a color filter method. For example, the colored layer 232 may be configured to represent one color using three subpixels to which one of red (R), green (G), or blue (B) is applied. In addition, white (W) may be added.
Applying yellow (Y) subpixels is preferable because it improves color reproduction and reduces power consumption.

In the light-emitting element 254, the combination of the colored layer 232 and the optical adjustment layer 224 creates a microcavity structure that allows light with high color purity to be extracted from the display device 10.
The thickness of the optical adjustment layer 224 may vary depending on the color of each sub-pixel. Furthermore, some sub-pixels may not have an optical adjustment layer.

Furthermore, it is preferable to apply a white-emitting EL layer as the EL layer 222 of the light-emitting element 254. By applying such a light-emitting element 254, the EL layer 222 of each subpixel is provided.
Since there is no need to paint the layers separately, costs can be reduced and yield can be improved, and the pixel section 11 can be made higher resolution. Alternatively, by providing an optical adjustment layer of different thicknesses for each sub-pixel, the EL layer 222 can be painted separately for each sub-pixel, in which case either the optical adjustment layer or the coloring layer, or both, may be omitted. In this case, at least the light-emitting layer of the EL layer 222 may be painted separately for each sub-pixel, while the other layers may be left unpainted.

Figure 14 shows an example in which an FPC 242 is provided that is electrically connected to the terminal portion 15. Therefore, the display device 10 shown in Figure 14 can also be called a display module.
Furthermore, a display device that does not have an FPC (Flexible Printed Circuit) or similar component can also be called a display panel.

The terminal section 15 is electrically connected to the FPC 242 via the connecting layer 243.

Figure 14 shows that the terminal portion 15 has a laminated structure consisting of wiring 16b and a conductive layer made of the same conductive film as the pixel electrode 225. This configuration of the terminal portion 15, with multiple conductive layers laminated together, is preferable because it not only reduces electrical resistance but also increases mechanical strength.

It is preferable to use materials that do not easily allow impurities such as water and hydrogen to diffuse for the insulating layer 211 and insulating layer 221. In other words, the insulating layer 211 and insulating layer 221 can function as barrier films. With such a configuration, even if moisture-permeable materials are used for the first substrate 201 and the second substrate 202, it is possible to effectively suppress the intrusion of impurities from the outside into the light-emitting element 254 and transistors, etc., thereby realizing a highly reliable display device.

Figure 14 shows a case where a hollow sealing structure has a space 250 between the first substrate 201 and the second substrate 202. For example, the space 250 may be filled with an inert gas such as nitrogen or a noble gas. Alternatively, the space 250 may be filled with a liquid crystal material or a fluid material such as oil. Or, the space 250 may be under reduced pressure. Note that the sealing method is not limited to these, and solid sealing filled with resin or the like may also be used.

[Cross-sectional configuration example 2]
Figure 15 shows an example of a display device configuration suitable for use when the pixel section 11 and the signal line driving circuit 13 are bent.

The display device 10 shown in Figure 15 is an example of a case in which a first substrate 201 and a second substrate 202 are bonded together by a sealing material 260, forming a solid encapsulation structure.

Furthermore, the first substrate 201 has an adhesive layer 261 and an insulating layer 216 on the adhesive layer 261, and transistors, light-emitting elements, etc. are provided on the insulating layer 216.
Similar to 21, materials that do not easily diffuse impurities such as water and hydrogen can be used.

Furthermore, an adhesive layer 262 is provided between the second substrate 202 and the insulating layer 221.

Furthermore, as shown in Figure 15, the insulating layer 213 has an opening on the outer periphery side of the first substrate 201, closer to the pixel section 11 and the signal line drive circuit 13. For example, when a resin material is used as the insulating layer 213, it is preferable to provide an opening that surrounds the pixel section 11 and the signal line drive circuit 13, etc. With this configuration, the vicinity of the side surface of the insulating layer 213 that is in contact with the outside,
Since the parts that overlap with the pixel section 11 and the signal line driving circuit 13 are not continuous, the diffusion of impurities such as water and hydrogen from the outside through the insulating layer 213 can be suppressed.

As shown in Figure 15, by using a solid encapsulation structure, the first substrate 201 and the second substrate 202
It becomes easier to maintain a uniform distance between the first substrate 201 and the second substrate 2
As 02, a flexible substrate can be suitably used. Therefore, the pixel portion 11
The scan line drive circuit 12 and the signal line drive circuit 13 can be bent or partially or completely used. For example, by attaching the display device 10 to a curved surface or by folding the pixel portion of the display device 10, various forms of electronic devices can be realized.
[Variations]
The following describes an example of a touch panel that has a touch sensor.

Figure 16 shows an example of a touch panel in which an on-cell type touch sensor is applied to the configuration illustrated in Figure 14.

A conductive layer 291 and a conductive layer 292 are provided on the outer surface of the second substrate 202, and an insulating layer 294 is provided covering them. A conductive layer 293 is also provided on the insulating layer 294. The conductive layer 293 is electrically connected to the two conductive layers 292, which are provided with the conductive layer 291 in between, through an opening provided in the insulating layer 294. The insulating layer 294 and the substrate 296 are bonded together by an adhesive layer 295.

The capacitance formed between conductive layer 291 and conductive layer 292 changes as the object to be detected approaches. This makes it possible to detect when the object to be detected is approaching or making contact. By arranging multiple conductive layers 291 and multiple conductive layers 292 in a grid pattern, positional information can be acquired.

Furthermore, a terminal portion 299 is provided in an area close to the outer periphery of the second substrate 202. Terminal portion 2
99 is electrically connected to FPC297 via the connection layer 298.

Here, the substrate 296 can also be used as a substrate that a sensing object such as a finger or stylus directly touches. In that case, it is preferable to provide a protective layer (ceramic coating, etc.) on the substrate 296. The protective layer may be, for example, silicon oxide, aluminum oxide, yttrium oxide,
Inorganic insulating materials such as yttria-stabilized zirconia (YSZ) can be used. Alternatively, tempered glass may be used for the substrate 296. The tempered glass can be one that has undergone physical or chemical treatment, such as ion exchange or air-cooling tempering, and has compressive stress applied to its surface. By placing the touch sensor on one side of the tempered glass and using the opposite side as the touch surface, for example, on the outermost surface of the electronic device, the overall thickness of the device can be reduced.

For example, a capacitive touch sensor can be used as a touch sensor. Capacitive types include surface-type capacitive sensors and projected-type capacitive sensors. Projected-type capacitive sensors include self-capacitive sensors and mutual-capacitive sensors. Mutual-capacitive sensors are preferable because they enable simultaneous multi-point detection. The following section will describe the case where a projected-type capacitive touch sensor is applied.

However, this is not the only option; various sensors capable of detecting the approach or contact of an object to be detected, such as a finger or stylus, can also be applied.

Here, we have shown a configuration of a so-called on-cell type touch panel in which wiring and other components constituting the touch sensor are formed on the outer surface of the second substrate 202, but the configuration is not limited to this. For example, an external (out-cell type) touch panel or an in-cell type touch panel configuration may also be applied. By using an on-cell or in-cell type touch panel configuration, the thickness of the display panel can be reduced even when touch panel functionality is added to it.

The above is an explanation of the cross-sectional configuration examples.

[Regarding each component]
The following sections will explain each of the components listed above.

〔substrate〕
The substrate of the display device can be made of a material having a flat surface. The substrate on the side that extracts light from the light-emitting element can be made of a material that transmits the light. For example, materials such as glass, quartz, ceramic, sapphire, and organic resin can be used.

By using a thin substrate, the display device can be made lighter and thinner. Furthermore, by using a substrate with sufficient thickness to allow for flexibility, a flexible display device can be realized.

Examples of glass that can be used include alkali-free glass, barium borosilicate glass, and aluminobosilicate glass.

Examples of materials that are flexible and transparent to visible light include glass of a thickness sufficient to be flexible, polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyacrylonitrile resin, polyimide resin, polymethyl methacrylate resin, polycarbonate (PC) resin, and polyethersulfone (PE).
Examples of materials include resins, polyamide resins, cycloolefin resins, polystyrene resins, polyamide-imide resins, polyvinyl chloride resins, and polytetrafluoroethylene (PTFE) resins. In particular, it is preferable to use materials with a low coefficient of thermal expansion, and for example, polyamide-imide resins, polyimide resins, and PET can be suitably used. In addition, substrates made by impregnating glass fibers with organic resin or substrates in which inorganic fillers are mixed with organic resin to lower the coefficient of thermal expansion can also be used. Since substrates made of such materials are lightweight, the display devices using such substrates can also be made lightweight.

Furthermore, the substrate on the side from which light is not extracted does not need to be translucent; therefore, in addition to the substrates mentioned above, metal substrates and the like can also be used. Metal substrates are preferable because they have high thermal conductivity and can easily conduct heat throughout the entire encapsulating substrate, thereby suppressing localized temperature rises in the display device.

There are no particular limitations on the material that constitutes the metal substrate, but for example, metals such as aluminum, copper, and nickel, or alloys such as aluminum alloys or stainless steel can be suitably used.

Furthermore, a substrate that has been treated to provide insulation, such as by oxidizing the surface of the metal substrate or forming an insulating film on the surface, may be used. For example, an insulating film may be formed using coating methods such as spin coating or dip coating, electrodeposition, vapor deposition, or sputtering, or an oxide film may be formed on the surface of the substrate by leaving it in an oxygen atmosphere, heating it, or by anodizing.

A flexible substrate is provided with a hard coat layer (e.g., a silicon nitride layer) to protect the surface of the display device from scratches, etc., and a layer of a material that can distribute pressure (e.g., an aramid resin layer).
These may be laminated. In addition, to suppress the reduction in the lifespan of the light-emitting element due to moisture, etc., a highly permeable insulating film may be laminated on a flexible substrate. For example, inorganic insulating materials such as silicon nitride, silicon oxynitride, aluminum oxide, and aluminum nitride can be used.

The substrate can also be constructed by stacking multiple layers. In particular, a configuration with a glass layer improves barrier properties against water and oxygen, resulting in a highly reliable display device.
For example, a substrate can be used in which a glass layer, an adhesive layer, and an organic resin layer are laminated from the side closest to the light-emitting element. By providing such an organic resin layer, cracking and fracture of the glass layer can be suppressed, and mechanical strength can be improved. By applying such a composite material of glass material and organic resin to the substrate, an extremely reliable and flexible display device can be made.

[Transistor]
The transistor in the display device has a conductive layer that functions as a gate electrode, a conductive layer that functions as a back gate electrode, a semiconductor layer, a conductive layer that functions as a source electrode, a conductive layer that functions as a drain electrode, and an insulating layer that functions as a gate insulating layer.

In other words, the transistor in one aspect of the present invention has a structure in which gate electrodes are provided above and below the channel.

The crystallinity of semiconductor materials used in transistors is not particularly limited; amorphous semiconductors are also available.
Any crystalline semiconductor (microcrystalline semiconductor, polycrystalline semiconductor, monocrystalline semiconductor, or semiconductor having a crystalline region in part) may be used. Using a crystalline semiconductor is preferable because it can suppress the degradation of transistor characteristics.

Furthermore, as semiconductor materials used in transistors, for example, oxide semiconductors can be used in the semiconductor layer. It is particularly preferable to use oxide semiconductors with a larger band gap than silicon. Using semiconductor materials with a wider band gap and lower carrier density than silicon is preferable because it can reduce the current in the off state of the transistor.

For example, the above oxide semiconductor may contain at least indium (In) or zinc (Zn).
Preferably contains ). More preferably In-M-Zn oxide (where M is Al, Ti,
It includes oxides represented by metals such as Ga, Ge, Y, Zr, Sn, La, Ce, or Hf.

In particular, it is preferable to use an oxide semiconductor layer as the semiconductor layer, which has multiple crystalline portions, the c-axis of which is oriented approximately perpendicular to the surface on which the semiconductor layer is formed or to the upper surface of the semiconductor layer, and in which no grain boundaries are observed between adjacent crystalline portions.

Because such oxide semiconductors lack grain boundaries, the stress caused by bending the display panel prevents cracks from forming in the oxide semiconductor layer. Therefore,
Such oxide semiconductors can be suitably used in flexible and curved display devices and the like.

Furthermore, by using an oxide semiconductor with such crystalline properties as the semiconductor layer, fluctuations in electrical properties can be suppressed, enabling the realization of highly reliable transistors.

Furthermore, transistors using oxide semiconductors with a larger band gap than silicon,
Due to its low off-current, it is possible to retain the charge stored in the capacitor connected in series with the transistor for a long period of time. By applying such a transistor to a pixel,
It is also possible to stop the drive circuit while maintaining the gradation of the image displayed in each display area.
As a result, a display device with extremely reduced power consumption can be realized. Alternatively, it is possible to switch between a drive mode that operates at a normal frame frequency and a drive mode that operates at a low frame frequency. In the drive mode that operates at a low frame frequency, the power consumption required for writing image data during the interval between writing image data can be reduced by writing the image data once and then extending the interval until the next image data is written.

[Conductive layer]
Materials that can be used for conductive layers such as the gate, source, and drain of transistors, as well as various wirings and electrodes that constitute display devices, include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, or tungsten, or alloys mainly composed of these metals. Films containing these materials can be used as single layers or in multilayer structures. For example, there are single-layer structures of aluminum films containing silicon, two-layer structures of aluminum films laminated on titanium films, two-layer structures of aluminum films laminated on tungsten films, two-layer structures of copper films laminated on copper-magnesium-aluminum alloy films, two-layer structures of copper films laminated on titanium films, two-layer structures of copper films laminated on tungsten films, three-layer structures of titanium films or titanium nitride films with aluminum films or copper films laminated on top and titanium films or titanium nitride films formed on top of those, and three-layer structures of molybdenum films or molybdenum nitride films with aluminum films or copper films laminated on top and molybdenum films or molybdenum nitride films formed on top of those. Furthermore, oxides such as indium oxide, tin oxide, or zinc oxide may be used. In addition, using copper containing manganese is preferable because it improves the controllability of the shape through etching.

Furthermore, as a translucent material that can be used for conductive layers such as various wirings and electrodes constituting the display device, conductive oxides such as indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, gallium-doped zinc oxide, or graphene can be used. Alternatively, metallic materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, or titanium, or alloy materials containing such metallic materials, can be used. Alternatively, nitrides of such metallic materials (e.g., titanium nitride) may be used. When using metallic materials, alloy materials (or their nitrides), they should be thinned to a degree that provides translucency. In addition, a laminated film of the above materials can be used as a conductive layer. For example, using a laminated film of a silver-magnesium alloy and indium tin oxide is preferable because it can enhance conductivity.

[Insulating layer]
Insulating materials that can be used for each insulating layer, overcoat, spacer, etc. include, for example, resins such as acrylic and epoxy, resins having siloxane bonds such as silicone resin, and inorganic insulating materials such as silicon oxide, silicon oxide nitride, silicon nitride, and aluminum oxide.

Furthermore, it is preferable that the light-emitting element is placed between a pair of insulating films with low water permeability. This prevents impurities such as water from entering the light-emitting element, thereby suppressing a decrease in the reliability of the device.

Examples of insulating films with low water permeability include films containing nitrogen and silicon, such as silicon nitride films and silicon oxide nitride films, and films containing nitrogen and aluminum, such as aluminum nitride films.
Silicon oxide films, silicon oxide nitride films, aluminum oxide films, etc., may also be used.

For example, the water vapor transmission rate of a low-permeability insulating film is 1 × ^10⁻⁵ [g/( ^m² ·day)]
Preferably 1 × ^10⁻⁶ [g/( ^m² ·day)] or less, more preferably 1 × 1
^0-7 [g/( ^m² ·day)] or less, more preferably 1 × ^10⁻⁸ [g/( ^m² ·day)].
(ay) The following applies:

[Adhesive layer, sealant]
Various types of curing adhesives can be used as adhesive layers or sealants, including UV-curing adhesives, reaction-curing adhesives, thermosetting adhesives, and anaerobic adhesives. These adhesives include epoxy resins, acrylic resins, silicone resins, phenolic resins, polyimide resins, imide resins, PVC (polyvinyl chloride) resins, and PVB (polyvinyl butyral).
Examples include resins, EVA (ethylene vinyl acetate) resin, etc. Materials with low moisture permeability, such as epoxy resin, are particularly preferred. Two-component resins may also be used. Adhesive sheets may also be used.

Furthermore, the above resin may contain a desiccant. For example, a substance that adsorbs moisture by chemical adsorption, such as an alkaline earth metal oxide (calcium oxide or barium oxide, etc.), can be used. Alternatively, a substance that adsorbs moisture by physical adsorption, such as a zeolite or silica gel, may be used. The inclusion of a desiccant is preferable because it can suppress the penetration of impurities such as moisture into the functional elements, thereby improving the reliability of the display panel.

Furthermore, by mixing fillers or light-scattering materials with high refractive index into the above resin, the light extraction efficiency from the light-emitting element can be improved. For example, titanium dioxide, barium oxide,
Zeolite, zirconium, etc., can be used.

[Light-emitting element]
As light-emitting elements, self-illuminating elements can be used, and this category includes elements whose brightness can be controlled by current or voltage. For example, light-emitting diodes (LEDs), organic EL elements, inorganic EL elements, etc., can be used.

The light-emitting element may be of the top-emission, bottom-emission, or dual-emission type. A conductive film that transmits visible light is used for the electrode that extracts light. Preferably, a conductive film that reflects visible light is used for the electrode that does not extract light.

The EL layer has at least an emissive layer. The EL layer may further have layers other than the emissive layer that contain a material with high hole injection properties, a material with high hole transport properties, a hole blocking material, a material with high electron transport properties, a material with high electron injection properties, or a bipolar material (a material with high electron transport and hole transport properties).

The EL layer may use either low-molecular-weight compounds or high-molecular-weight compounds, and may also contain inorganic compounds. Each layer constituting the EL layer is produced by a vapor deposition method (including vacuum deposition).
It can be formed by methods such as transfer, printing, inkjet, and coating.

When a voltage higher than the threshold voltage of the light-emitting element is applied between the cathode and anode, holes are injected into the EL layer from the anode side and electrons are injected from the cathode side. The injected electrons and holes recombine in the EL layer, causing the light-emitting material contained in the EL layer to emit light.

When using a white-emitting light-emitting element, it is preferable to have a configuration in the EL layer that includes two or more types of light-emitting materials. For example, white light emission can be obtained by selecting two or more light-emitting materials such that the light emitted by each of them is complementary in color. For example,
These are light-emitting substances that emit light in the following colors: R (red), G (green), B (blue), Y (yellow), O (orange), etc.
Or, among luminescent materials that exhibit emission containing two or more spectral components of R, G, and B,
It is preferable to include two or more. Furthermore, it is preferable to use an light-emitting element whose emission spectrum has two or more peaks within the wavelength range of the visible light region (for example, 350 nm to 750 nm). In addition, it is preferable that the emission spectrum of a material having a peak in the yellow wavelength region also has spectral components in the green and red wavelength regions.

The EL layer is preferably configured by laminating an EL layer containing an EL-emitting material that emits one color and an EL layer containing an EL-emitting material that emits another color. For example, the multiple EL-emitting layers in the EL layer may be laminated in contact with each other, or they may be laminated with regions that do not contain any EL-emitting material in between. For example, a region may be provided between a fluorescent EL layer and a phosphorescent EL layer that contains the same material as the fluorescent EL layer or phosphorescent EL layer (e.g., a host material, an assist material) but does not contain any EL-emitting material. This makes it easier to manufacture the light-emitting element and reduces the driving voltage.

Furthermore, the light-emitting element may be a single element having one EL layer, or a tandem element in which multiple EL layers are stacked with a charge generation layer in between.

Examples of conductive films that transmit visible light include indium oxide and indium tin oxide (ITO).
Indium zinc oxide, zinc oxide, and zinc oxide with added gallium can be used. Furthermore, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, or titanium, alloys containing these metal materials, or nitrides of these metal materials (e.g., titanium nitride) can also be used by forming them thinly enough to be translucent.
The laminated film of the above materials can be used as a conductive layer. For example, using a laminated film of a silver-magnesium alloy and ITO is preferable because it can enhance conductivity. Graphene may also be used.

The conductive film that reflects visible light can be made of metal materials such as aluminum, gold, platinum, silver, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, or palladium, or alloys containing these metal materials. Lanthanum, neodymium, or germanium may also be added to the above metal materials or alloys. In addition, alloys containing aluminum (aluminum alloys) such as aluminum-titanium alloys, aluminum-nickel alloys, and aluminum-neodymium alloys, as well as silver-copper alloys and silver-palladium-copper alloys,
Silver-containing alloys such as silver-magnesium alloys can be used. Silver-containing alloys such as copper alloys can be used.
It is preferable because it has high heat resistance. Furthermore, by laminating a metal film or oxide semiconductor film in contact with the aluminum alloy film, oxidation of the aluminum alloy film can be suppressed. The metal film,
Examples of materials for oxide semiconductor films include titanium and titanium oxide. Alternatively, a conductive film that transmits visible light and a film made of a metallic material may be laminated. For example, a laminated film of silver and ITO, or a laminated film of a silver-magnesium alloy and ITO can be used.

The conductive layers can be formed using methods such as vapor deposition or sputtering. In addition,
It can be formed using ejection methods such as inkjet printing, printing methods such as screen printing, or plating methods.

Furthermore, the layers containing the light-emitting layer, as well as materials with high hole injection, high hole transport, high electron transport, and high electron injection, bipolar materials, etc., may each contain inorganic compounds such as quantum dots or polymer compounds (oligomers, dendrimers, polymers, etc.). For example, quantum dots can be used in the light-emitting layer to function as a light-emitting material.

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

[Colored layer]
Materials that can be used for the colored layer include metal materials, resin materials, and resin materials containing pigments or dyes.

[Light blocking layer]
Materials that can be used for the light-shielding layer include carbon black, oxide semiconductors, and composite oxides containing solid solutions of multiple oxide semiconductors. Furthermore, a laminated film containing the material for the colored layer can also be used for the light-shielding layer. For example, a laminated structure can be used consisting of a film containing the material for a colored layer that transmits light of a certain color, and a film containing the material for a colored layer that transmits light of another color. Using the same material for both the colored layer and the light-shielding layer is preferable because it allows for the common use of equipment and simplifies the process.

[Connection layer]
The connection layer connecting the FPC or IC to the terminals uses an anisotropic conductive film (ACF: Anis
(Otropic Conductive Film) or anisotropic conductive paste (ACP:
Anisotropic Conductive Paste, etc., can be used.

The above is an explanation of each component.

This embodiment can be implemented in appropriate combination with other embodiments described herein, at least in part.

(Embodiment 3)
This embodiment describes an example of a method for manufacturing a display device using a flexible substrate.

Here, layers including display elements, circuits, wiring, electrodes, and insulating layers, as well as optical components such as colored layers and light-shielding layers, are collectively referred to as element layers. For example, an element layer may include a light-emitting element, and in addition to the light-emitting element, it may also include wiring electrically connected to the light-emitting element, and elements such as transistors used in pixels and circuits.

Furthermore, in this context, the flexible material that supports the element layer at the stage when the light-emitting element is completed (when the manufacturing process is finished) will be referred to as a substrate. For example, substrates include extremely thin films with a thickness of 10 nm to 300 μm.

There are two main methods for forming an element layer on a flexible substrate with an insulating surface. One is to form the element layer directly on the flexible substrate. The other is to form the element layer on a support substrate different from the flexible substrate, then peel the element layer from the support substrate and transfer the element layer to the substrate. Although not explained in detail here, in addition to the above two methods, there is also a method in which an element layer is formed on a non-flexible substrate, and the substrate is made flexible by thinning it through polishing or other means.

If the material constituting the substrate has heat resistance to the heat generated during the element layer formation process, it is preferable to form the element layer directly on the substrate because it simplifies the process. In this case, it is preferable to form the element layer with the substrate fixed to a support base material because it facilitates transport within and between devices.

Furthermore, when using a method in which the element layer is formed on a support substrate and then transferred to a substrate, first a release layer and an insulating layer are laminated on the support substrate, and the element layer is formed on the insulating layer. Subsequently, the element layer is delaminated between the support substrate and the element layer and transferred to the substrate. At this time, it is sufficient to select a material that causes delamination at the interface between the support substrate and the release layer, at the interface between the release layer and the insulating layer, or within the release layer.
This method is preferable because, by using heat-resistant materials for the support substrate and release layer, the upper limit of the temperature required when forming the element layer can be increased, thereby enabling the formation of an element layer with a more reliable element.

For example, as a release layer, a layer containing a high-melting-point metal material such as tungsten and a layer containing an oxide of the said metal material are laminated together. Furthermore, it is preferable to use a layer on the release layer that consists of multiple layers of silicon oxide, silicon nitride, silicon oxynitride, silicon nitride oxide, etc. In this specification, oxynitride refers to a material in which the oxygen content is greater than the nitrogen content, and nitride oxide refers to a material in which the nitrogen content is greater than the oxygen content.

Methods for separating the element layer from the support substrate include applying mechanical force, etching the separation layer, or impregnating the separation interface with a liquid. Alternatively, separation may be performed by heating or cooling, taking advantage of the difference in thermal expansion between the two layers forming the separation interface.

When initiating delamination, it is preferable to first form a starting point for delamination and then proceed with the delamination from that starting point. The starting point for delamination can be formed by locally heating a portion of the insulating layer or delamination layer with laser light or the like, or by physically cutting or penetrating a portion of the insulating layer or delamination layer with a sharp object.

Furthermore, if peeling is possible at the interface between the support substrate and the insulating layer, a peeling layer may not be necessary.

For example, by using glass as the support substrate and an organic resin such as polyimide as the insulating layer, delamination can be achieved at the interface between the glass and the organic resin. Furthermore, the remaining polyimide or other organic resin can also be used as a substrate.

Alternatively, a heating layer may be provided between the support substrate and an insulating layer made of organic resin, and delamination may be performed at the interface between the heating layer and the insulating layer by heating the heating layer. Various materials can be used as the heating layer, such as materials that generate heat when an electric current is passed through them, materials that generate heat when light is absorbed, and materials that generate heat when a magnetic field is applied. For example, semiconductors, metals, and insulators can be selected and used as the heating layer.

The following describes a more specific example of a manufacturing method. By changing the layer formed as the peelable layer in the manufacturing method described below, a flexible input/output device according to one aspect of the present invention can also be manufactured.

First, island-shaped release layers 303 are formed on the fabricated substrate 301, and the layer to be released 3 is placed on the release layer 303.
Forming 05 (Figure 17(A)). Separately, island-shaped release layers 323 are formed on the fabricated substrate 321, and the layer to be released 325 is formed on the release layers 323 (Figure 17(B)).

Here, an example of forming an island-shaped delamination layer is shown, but the method is not limited to this. In this process, when peeling the layer to be peeled from the fabricated substrate, a material is selected that causes delamination at the interface between the fabricated substrate and the delamination layer, at the interface between the delamination layer and the layer to be peeled, or within the delamination layer. In this embodiment, the case in which delamination occurs at the interface between the layer to be peeled and the delamination layer is illustrated, but the method is not limited to this depending on the combination of materials used for the delamination layer and the layer to be peeled. When the layer to be peeled has a laminated structure, the layer in contact with the delamination layer is specifically referred to as the first layer.

For example, if the release layer has a laminated structure of a tungsten film and a tungsten oxide film, delamination may occur at the interface (or near the interface) between the tungsten film and the tungsten oxide film, and a portion of the release layer (in this case, the tungsten oxide film) may remain on the side of the layer being released. The remaining release layer on the side of the layer being released may be removed afterward.

For example, if the release layer has a laminated structure of a tungsten film and a tungsten oxide film, delamination may occur at the interface (or near the interface) between the tungsten film and the tungsten oxide film, and a portion of the release layer (in this case, the tungsten oxide film) may remain on the side of the layer being released. The remaining release layer on the side of the layer being released may be removed afterward.

The fabricated substrate must have at least enough heat resistance to withstand the processing temperature during the fabrication process. Examples of suitable substrates include glass substrates, quartz substrates, sapphire substrates, semiconductor substrates, ceramic substrates, metal substrates, resin substrates, and plastic substrates.

When using a glass substrate for fabrication, it is preferable to form an insulating film such as a silicon oxide film, silicon oxide-nitride film, silicon nitride film, or silicon nitride-oxide film as an underlayer between the fabrication substrate and the release layer, as this prevents contamination from the glass substrate.

The release layer can be formed using an element selected from tungsten, molybdenum, titanium, tantalum, niobium, nickel, cobalt, zirconium, zinc, ruthenium, rhodium, palladium, osmium, iridium, or silicon, an alloy material containing such an element, or a compound material containing such an element. The crystal structure of the silicon-containing layer may be amorphous, microcrystalline, or polycrystalline. Oxide semiconductors such as aluminum oxide, gallium oxide, zinc oxide, titanium dioxide, indium oxide, indium tin oxide, indium zinc oxide, or In-Ga-Zn oxide may also be used. Using high-melting-point metal materials such as tungsten, titanium, or molybdenum for the release layer is preferable because it increases the degree of freedom in the formation process of the layer to be released.

The release layer can be formed by methods such as sputtering, plasma CVD, coating (including spin coating, droplet ejection, and dispensing), and printing. The thickness of the release layer is, for example, 10 nm to 200 nm, preferably 20 nm to 100 nm.

When the release layer has a single-layer structure, it is preferable to form a layer containing a tungsten layer, a molybdenum layer, or a mixture of tungsten and molybdenum. Alternatively, a layer containing tungsten oxide or oxidized nitride, a layer containing molybdenum oxide or oxidized nitride, or a layer containing oxide or oxidized nitride of a mixture of tungsten and molybdenum may be formed.
A mixture of tungsten and molybdenum is equivalent to, for example, a tungsten-molybdenum alloy.

Furthermore, when forming a laminated structure of a tungsten-containing layer and a tungsten oxide-containing layer as the release layer, it is possible to utilize the fact that a tungsten oxide-containing layer is formed at the interface between the tungsten layer and the insulating film by forming a tungsten-containing layer and then forming an insulating film made of oxide on top of it. Alternatively, the surface of the tungsten-containing layer may be treated with thermal oxidation, oxygen plasma treatment, nitrous oxide ( _N₂O ) plasma treatment, or treatment with a highly oxidizing solution such as ozonated water to form a tungsten oxide-containing layer. Plasma treatment and heat treatment may also be performed in an atmosphere of oxygen, nitrogen, nitrous oxide alone, or a mixed gas of these gases and other gases. By changing the surface state of the release layer through the above plasma treatment or heat treatment, it is possible to control the adhesion between the release layer and the insulating film that is later formed.

Furthermore, if delamination is possible at the interface between the fabricated substrate and the layer to be delaminated, a delamination layer may not be necessary. For example, glass is used as the fabricated substrate, and an organic resin such as polyimide, polyester, polyolefin, polyamide, polycarbonate, or acrylic is formed in contact with the glass. Next, the adhesion between the fabricated substrate and the organic resin is improved by laser irradiation or heat treatment. Then, an insulating film or transistor is formed on the organic resin. Subsequently, by performing laser irradiation at a higher energy density than the previous laser irradiation, or by performing heat treatment at a higher temperature than the previous heat treatment, delamination can be achieved at the interface between the fabricated substrate and the organic resin. Also, during delamination,
The substrate and the organic resin may be separated by permeating the interface between them with a liquid.

In this method, since insulating films and transistors are formed on an organic resin with low heat resistance, high temperatures cannot be applied to the substrate during the manufacturing process. However, since transistors using oxide semiconductors do not require high-temperature manufacturing processes, they can be suitably formed on organic resins.

The organic resin may be used as a substrate to constitute the device, or the organic resin may be removed and another substrate may be bonded to the exposed surface of the peelable layer using an adhesive. Alternatively, another substrate (support film) may be bonded to the organic resin using an adhesive.

Alternatively, a metal layer may be placed between the fabricated substrate and the organic resin, and the metal layer may be heated by passing an electric current through it, thereby causing delamination at the interface between the metal layer and the organic resin.

The insulating layer (first layer) formed in contact with the release layer is preferably formed as a single layer or multiple layers using a silicon nitride film, silicon oxynitride film, silicon oxide film, or silicon nitride oxide film. However, it is not limited to this, and the optimal material can be selected depending on the material used for the release layer.

The insulating layer can be formed using sputtering, plasma CVD, coating, printing, etc. For example, by plasma CVD, the film deposition temperature can be set to 250°C or higher and 400°C or higher.
By forming it at temperatures below ℃, a dense and highly moisture-resistant film can be created.
The thickness of the insulating layer is preferably 10 nm to 3000 nm, and more preferably 200 nm to 1500 nm.

Next, the fabricated substrate 301 and the fabricated substrate 321 are bonded together using the adhesive layer 307 so that the surfaces on which the peel-off layers are formed face each other, and the adhesive layer 307 is cured (Figure 17).
C)).

Furthermore, it is preferable to perform the bonding of the fabricated substrate 301 and the fabricated substrate 321 under reduced pressure.

Although Figure 17(C) shows a case where the sizes of the release layer 303 and the release layer 323 are different, as shown in Figure 17(D), release layers of the same size may also be used.

The adhesive layer 307 is positioned to overlap with the release layer 303, the layer to be released 305, the layer to be released 325, and the release layer 323. The end of the adhesive layer 307 is attached to the release layer 303 or the release layer 323.
It is preferable that the edge is located inside at least one of the edges (the one to be peeled off first). This prevents the fabricated substrate 301 and the fabricated substrate 321 from adhering too strongly, thereby preventing a decrease in the yield of the subsequent peeling process.

The adhesive layer 307 can be made of various types of adhesives, such as photocurable adhesives (e.g., UV-curable adhesives), reaction-curable adhesives, thermosetting adhesives, or anaerobic adhesives. Examples of these adhesives include epoxy resins, acrylic resins, silicone resins, phenolic resins, polyimide resins, imide resins, PVC resins, PVB resins, and EVA resins. Materials with low moisture permeability, such as epoxy resins, are particularly preferred. It is preferable to use an adhesive material with low fluidity so that it can be placed only in the desired area. For example, adhesive sheets, tack sheets, or sheet-like or film-like adhesives may be used. For example, OCA (optica
A clear, adhesive film can be suitably used.

The adhesive may have tackiness before bonding, or it may develop tackiness after bonding through heating or light irradiation.

Furthermore, the above resin may contain a desiccant. For example, a substance that adsorbs moisture by chemical adsorption, such as an alkaline earth metal oxide (calcium oxide or barium oxide, etc.), can be used. Alternatively, a substance that adsorbs moisture by physical adsorption, such as a zeolite or silica gel, may be used. The inclusion of a desiccant is preferable because it can suppress the deterioration of the functional elements due to the intrusion of moisture from the atmosphere, thereby improving the reliability of the device.

Next, the starting point for delamination is formed by irradiation with laser light (Figure 18(A)(B)).

The fabricated substrates 301 and 321 may be peeled off from either side. If the sizes of the release layers are different, the substrate with the larger release layer may be peeled off first, or the substrate with the smaller release layer may be peeled off first. If semiconductor elements, light-emitting elements, or other elements are fabricated on only one of the substrates, the substrate on which the elements are formed may be peeled off first, or the other substrate may be peeled off first.
Here, we show an example in which the fabricated substrate 301 is peeled off first.

The laser beam is irradiated onto the region where the hardened adhesive layer 307, the layer to be peeled off 305, and the peeling layer 303 overlap (see arrow P1 in Figure 18(A)).

By removing a portion of the first layer, a starting point for delamination can be formed (see the area enclosed by the dotted line in Figure 18(B)). At this time, not only the first layer, but also other layers of the delamination layer 305 and the delamination layer 3
03. A portion of the adhesive layer 307 may be removed.

It is preferable to irradiate the substrate with the peel-off layer to be peeled from the substrate side. When irradiating the region where peel-off layer 303 and peel-off layer 323 overlap with the laser beam, the fabricated substrate 301 and peel-off layer 303 can be selectively peeled off by creating cracks only in the peel-off layer 305 of the two peel-off layers 305 and 325 (see the area enclosed by the dotted line in Figure 18(B). Here, an example is shown in which a portion of each layer constituting the peel-off layer 305 is removed).

Then, the peeled layer 305 and the fabricated substrate 301 are separated from the starting point of the formed peeling (Figure 18(C)(D)). This separates the peeled layer 305 from the fabricated substrate 301 and the fabricated substrate 321.
It can be transposed to this.

For example, the peeled layer 305 and the fabricated substrate 301 can be separated from the peeling point by physical force (such as peeling it off with human hands or jigs, or separating it while rotating rollers).

Furthermore, a liquid such as water is permeated into the interface between the release layer 303 and the layer to be released 305 to produce the substrate 3
The 01 and the peeled layer 305 may be separated. Separation can be easily achieved by the liquid seeping between the peeled layer 303 and the peeled layer 305 due to capillary action. In addition, it is possible to suppress the adverse effects of static electricity generated during peeling on the functional elements contained in the peeled layer 305 (such as the semiconductor elements being destroyed by static electricity).

Next, the exposed peelable layer 305 and the substrate 331 are bonded together using the adhesive layer 333.
The adhesive layer 333 is cured (Figure 19(A)).

Furthermore, it is preferable to perform the bonding of the peelable layer 305 and the substrate 331 under a reduced pressure atmosphere.

Next, the starting point for delamination is formed by irradiation with laser light (Figure 19(B)(C)).

The laser beam is irradiated onto the region where the hardened adhesive layer 333, the layer to be peeled 325, and the peeling layer 323 overlap (see arrow P2 in Figure 19(B)). By removing a portion of the first layer, a starting point for peeling can be formed (see the area enclosed by the dotted line in Figure 19(C). Here, an example is shown where a portion of each layer constituting the layer to be peeled 325 is removed). At this time, not only the first layer,
Other layers of the peel-off layer 325, or parts of the peel-off layer 323 and adhesive layer 333 may be removed.

It is preferable to irradiate the fabricated substrate 321, on which the peeling layer 323 is provided, with laser light.

Then, the peeled layer 325 and the fabricated substrate 321 are separated from the starting point of the formed peeling (Figure 19(D)). This allows the peeled layer 305 and the peeled layer 325 to be transferred onto the substrate 331.

Subsequently, another substrate can be attached to the peel-off layer 325.

The exposed peelable layer 325 and the substrate 341 are bonded together by the adhesive layer 343.
The 43 is cured (Figure 20(A)). Here, an example is shown in which the substrate 341 has openings provided in advance.

As a result, the layer to be peeled off can be sandwiched between a pair of flexible substrates.

Subsequently, as shown in Figure 20(B), unnecessary edges of substrates 331, 341, etc., may be cut and removed. At this time, a portion of the edges of the peelable layer 305 and the peelable layer 325 may be cut simultaneously.

By the above method, a flexible device can be manufactured. By using the configuration exemplified in the above embodiment for the peelable layer, a flexible display device can be manufactured.

In the method for manufacturing a light-emitting device according to one embodiment of the present invention described above, a pair of manufactured substrates, each provided with a release layer and a layer to be released, are bonded together. Then, a starting point for release is formed by irradiation with laser light, making the respective release layer and layer to be released easier to release, and then the release is performed. This improves the yield of the release process.

Furthermore, after bonding together a pair of fabricated substrates, each having a peelable layer formed on it,
The peel-off layer can be removed, and the substrates that make up the device to be manufactured can be bonded to the peel-off layer. Therefore, when bonding the peel-off layers together, it is possible to bond together substrates with low flexibility, improving the alignment accuracy of the bonded substrates compared to when bonding together flexible substrates.

Furthermore, as shown in Figure 21(A), the end of the region 351 to be peeled off from the peeled layer 305 is
It is preferable that the peeling layer 303 be located inside the edge of the peeling layer 303. This can increase the yield of the peeling process. Also, if there are multiple regions 351, a peeling layer 303 may be provided for each region 351 as shown in Figure 21(B), or as shown in Figure 21(C), 1
Multiple regions 351 may be provided on one of the release layers 303.

The above is a description of the method for manufacturing a flexible display device.

This embodiment can be implemented in appropriate combination with other embodiments described herein, at least in part.

(Embodiment 4)
This embodiment describes an example of an electronic device to which a display device according to one aspect of the present invention can be applied.

Electronic devices and lighting devices can be manufactured using a display device according to one aspect of the present invention. By using a display device according to one aspect of the present invention, electronic devices and lighting devices can be manufactured that can obtain a large capacity even in a small area. By using a display device according to one aspect of the present invention, electronic devices and lighting devices can be manufactured that can obtain a large capacity even when performing grayscale display while maintaining a low voltage.

Examples of electronic devices include television sets, desktop or notebook personal computers, computer monitors, digital cameras, digital video cameras, digital photo frames, mobile phones, portable game consoles, personal digital assistants, audio playback devices, and large game machines such as pachinko machines.

An electronic device or lighting device according to one aspect of the present invention can be used on the interior or exterior walls of a house or building.
Alternatively, it can be incorporated along the curved surfaces of the interior or exterior of a vehicle.

An electronic device according to one aspect of the present invention may have a secondary battery, and it is preferable that the secondary battery can be charged using contactless power transmission.

Examples of secondary batteries include lithium-ion secondary batteries such as lithium polymer batteries (lithium-ion polymer batteries) that use a gel-like electrolyte, nickel-metal hydride batteries, nickel-cadmium batteries, organic radical batteries, lead-acid batteries, air secondary batteries, nickel-zinc batteries, and silver-zinc batteries.

An electronic device according to one aspect of the present invention may have an antenna. By receiving a signal with the antenna, the display unit can display images, information, etc. Furthermore, if the electronic device has an antenna and a secondary battery, the antenna may be used for contactless power transmission.

An electronic device according to one aspect of the present invention may have sensors (including those with the function of measuring force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation).

An electronic device according to one aspect of the present invention can have various functions. For example, it can have a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date or time, a function to execute various software (programs), a wireless communication function, a function to read programs or data recorded on a recording medium, and so on.

Furthermore, electronic devices having multiple display units may have functions such as primarily displaying image information on one display unit and primarily displaying text information on another display unit, or displaying three-dimensional images by displaying images that take parallax into account on multiple display units. Furthermore, electronic devices having a picture receiving unit may have functions such as capturing still images or moving images, automatically or manually correcting captured images, saving captured images to a recording medium (external or built into the electronic device), and displaying captured images on a display unit. It should be noted that the functions of an electronic device according to one aspect of the present invention are not limited to these, and it may have a variety of functions.

Figures 22(A), (B), (C), (D), and (E) show an example of an electronic device having a curved display unit 7000. The display unit 7000 has a curved display surface and can display information along the curved surface. The display unit 7000 may also be flexible.

The display unit 7000 is manufactured using a display device or the like according to one aspect of the present invention. According to one aspect of the present invention, it is possible to provide an electronic device that has reduced power consumption, a curved display unit, and high reliability.

Figures 22(A) and (B) show an example of a mobile phone. Figure 22(A) shows mobile phone 71.
The mobile phone 7110 shown in Figure 00 and Figure 22(B) consists of a housing 7101 and a display unit 7, respectively.
000, operation button 7103, external connection port 7104, speaker 7105, microphone 71
It has 06, etc. The mobile phone 7110 shown in Figure 22(B) further has a camera 7107.

Each mobile phone is equipped with a touch sensor on the display unit 7000. All operations, such as making a call or entering text, can be performed by touching the display unit 7000 with a finger or stylus.

Furthermore, the power can be turned ON or OFF by operating the operation button 7103, and the display unit 7000
You can switch the type of image displayed. For example, you can switch from the email composition screen to the main menu screen.

Furthermore, by installing a detection device such as a gyro sensor or accelerometer inside the mobile phone, the orientation of the mobile phone (vertical or horizontal) can be determined, and the orientation of the display on the display unit 7000 can be automatically switched. The orientation of the display can also be switched by touching the display unit 7000, operating the operation button 7103, or by voice input using the microphone 7106.

Figures 22(C) and (D) show examples of personal digital assistants (PADs). The PAD 7200 shown in Figure 22(C) and the PAD 7210 shown in Figure 22(D) each have a housing 7201 and a display unit 7000. They may also have operation buttons, external connection ports, speakers, microphones, antennas, cameras, or batteries. The display unit 7000 is equipped with a touch sensor. The PAD can be operated by touching the display unit 7000 with a finger or stylus.

The personal information terminal illustrated in this embodiment has one or more functions selected from, for example, a telephone, a notebook, or an information viewing device. Specifically, each can be used as a smartphone. The personal information terminal illustrated in this embodiment can run various applications such as mobile phone calls, email, document viewing and creation, music playback, internet communication, and computer games.

The personal digital assistants 7200 and 7210 can display text and image information on multiple surfaces. For example, as shown in Figures 22(C) and (D), three operation buttons 7202 can be displayed on one surface, and information 7203, shown as a rectangle, can be displayed on another surface. Figure 22(C) shows an example where information is displayed on the upper side of the personal digital assistant, and Figure 22(D) shows an example where information is displayed on the upper side of the personal digital assistant.
Now, let's look at an example where information is displayed on the side of a mobile device. Information may also be displayed on three or more sides of the mobile device.

Examples of information include notifications from social networking services (SNS), displays indicating incoming emails or phone calls, the subject or sender name of emails, date and time, battery level, and antenna signal strength. Alternatively, operation buttons or icons may be displayed in place of the information.

For example, a user of the personal digital assistant 7200 would carry the personal digital assistant 7200 in the breast pocket of their clothing.
With the device stored, you can check its display (information 7203 in this case).

Specifically, the mobile information terminal 7200 records the caller's phone number or name, etc., of the incoming call.
The display is positioned so that it can be observed from above. The user can check the display and decide whether or not to answer the call without taking the personal information terminal 7200 out of their pocket.

Figure 22(E) shows an example of a television system. The television system 7300 is housed in a casing 7
The display unit 7000 is incorporated into 301. Here, the stand 7303 supports the housing 7
This shows the configuration that supported 301.

The television device 7300 shown in Figure 22(E) can be operated using the operation switches on the housing 7301 or a separate remote control unit 7311. Alternatively, the display unit 70
The 00 may be equipped with a touch sensor, and may be operated by touching the display unit 7000 with a finger or the like. The remote control operator 7311 may have a display unit that displays information output from the remote control operator 7311. Channels and volume can be operated and the image displayed on the display unit 7000 can be operated using the operation keys or touch panel provided on the remote control operator 7311.

The television system 7300 is configured to include a receiver and a modem. The receiver can receive general television broadcasts. Furthermore, by connecting to a wired or wireless communication network via the modem, it is possible to perform one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication.

Figure 22(F) shows an example of a lighting device having a curved light-emitting section.

The light-emitting section of the lighting device shown in Figure 22(F) is manufactured using a display device or the like according to one aspect of the present invention. According to one aspect of the present invention, a lighting device can be provided that has reduced power consumption, is equipped with a curved light-emitting section, and is highly reliable.

The light-emitting section 7411 of the lighting device 7400 shown in Figure 22(F) has a configuration in which two convexly curved light-emitting sections are arranged symmetrically. Therefore, the lighting device 7400 can illuminate in all directions.

Furthermore, the light-emitting section of the lighting device 7400 may be flexible. The light-emitting section may be fixed with a plastic material or a movable frame or other material, and the light-emitting surface of the light-emitting section may be freely bent according to the application.

The lighting device 7400 has a base portion 7401 equipped with an operating switch 7403, and a light-emitting portion supported on the base portion 7401.

Although this example illustrates a lighting device in which the light-emitting part is supported by a base, it is also possible to use a housing containing the light-emitting part by fixing it to the ceiling or suspending it from the ceiling.
Because the light-emitting surface can be curved, it is possible to curve the light-emitting surface into a concave shape to brightly illuminate a specific area, or to curve the light-emitting surface into a convex shape to brightly illuminate the entire room.

Figures 23(A) to 23(I) show a flexible and bendable display section 70.
An example of a portable information terminal having 01 is shown.

The display unit 7001 is manufactured using a display device or the like according to one aspect of the present invention. For example, a display device or the like that can be bent with a radius of curvature of 0.01 mm or more and 150 mm or less can be used. The display unit 7001 may also be equipped with a touch sensor, allowing the portable information terminal to be operated by touching the display unit 7001 with a finger or the like. According to one aspect of the present invention, a highly reliable electronic device equipped with a flexible display unit can be provided.

Figures 23(A) and (B) are perspective views showing an example of a personal digital assistant (PDA). Personal digital assistant 75
00 includes a housing 7501, a display unit 7001, a pull-out member 7502, an operation button 7503, etc.

The portable information terminal 7500 has a flexible display unit 7001 that is wound in a roll shape inside a housing 7501. The display unit 7001 can be pulled out using a pull-out member 7502.

Furthermore, the portable information terminal 7500 can receive video signals using its built-in control unit, and the received video can be displayed on the display unit 7001. The portable information terminal 7500 also has a built-in battery. In addition, the housing 7501 may be equipped with terminals for connecting connectors, and the video signal and power may be supplied directly from an external source via wires.

Furthermore, the operation button 7503 allows for power ON/OFF operation, switching of displayed images, and other functions. While Figures 23(A) and (B) show an example where the operation button 7503 is located on the side of the portable information terminal 7500, the device is not limited to this configuration.
It may be placed on the same side as the display surface (the front side) or on the back side.

Figure 23(B) shows the portable information terminal 7500 with the display unit 7001 extended.
In this state, an image can be displayed on the display unit 7001. Alternatively, the portable information terminal 7500 may display different images depending on whether a portion of the display unit 7001 is rolled up as shown in Figure 23(A) or extended as shown in Figure 23(B). For example, Figure 23
When in state (A), the power consumption of the portable information terminal 7500 can be reduced by hiding the rolled portion of the display unit 7001.

Furthermore, to ensure that the display surface of the display unit 7001 becomes flat when it is pulled out, a reinforcing frame may be provided on the side of the display unit 7001.

In addition to this configuration, a speaker may be provided in the enclosure, and audio may be output based on the audio signal received along with the video signal.

Figures 23(C) to 23(E) show examples of foldable portable information terminals.
Figure 23(C) shows the device in its unfolded state, Figure 23(D) shows the device in an intermediate state between being unfolded or folded, and Figure 23(E) shows the portable information terminal 7600 in its folded state. The portable information terminal 7600 offers excellent portability in its folded state and excellent overviewability in its unfolded state due to its seamless, wide display area.

The display unit 7001 is supported by three housings 7601 connected by a hinge 7602. By bending the two housings 7601 via the hinge 7602, the portable information terminal 7600 can be reversibly transformed from an unfolded state to a folded state.

Figures 23(F) and (G) show an example of a foldable portable information terminal. Figure 23(F)
Figure 23(G) shows the portable information terminal 7650 in the folded state with the display unit 7001 facing inward. The portable information terminal 7650 has a display unit 7001 and a non-display unit 7651. When the portable information terminal 7650 is not in use, the display unit 7001 can be folded inward to allow the display unit 7001 to be hidden.
It can suppress dirt and scratches.

Figure 23(H) shows an example of a flexible portable information terminal. The portable information terminal 7700 has a housing 7701 and a display unit 7001. Furthermore, it has an input means, a button 7703a
7703b, speaker 7704a, 7704b which is an audio output means, external connection port 7
It may also have components such as 705, a microphone 7706, etc. Furthermore, the portable information terminal 7700 can be equipped with a flexible battery 7709. The battery 7709 may be, for example, connected to the display unit 7
It may be placed on top of 001.

The housing 7701, the display unit 7001, and the battery 7709 are flexible. Therefore,
It is easy to bend the personal digital information terminal 7700 into a desired shape and to twist the personal digital information terminal 7700. For example, the personal digital information terminal 7700 can be used by bending it so that the display unit 7001 is on the inside or outside. Alternatively, the personal digital information terminal 7700
It can also be used in a rolled state. Thus, the housing 7701 and the display unit 7
Because 001 can be freely deformed, the portable information terminal 7700 has the advantage of being less prone to damage even if it is dropped or subjected to unintended external force.

Furthermore, because the portable information terminal 7700 is lightweight, it can be conveniently used in various situations, such as by holding the top of the casing 7701 with a clip and hanging it, or by fixing the casing 7701 to a wall with a magnet or the like.

Figure 23(I) shows an example of a wristwatch-type personal information terminal. The personal information terminal 7800 has a band 7801, a display unit 7001, input/output terminals 7802, operation buttons 7803, etc. The band 7801 functions as a housing. The personal information terminal 7800 can also be equipped with a flexible battery 7805. The battery 7805 is, for example, connected to the display unit 70
It may be placed in conjunction with 01 or band 7801, etc.

The band 7801, the display unit 7001, and the battery 7805 are flexible. Therefore, it is easy to bend the portable information terminal 7800 into a desired shape.

The operation button 7803 can be assigned various functions, including time setting, power on/off operation, wireless communication on/off operation, silent mode activation/deactivation, and power saving mode activation/deactivation. For example, the functions of the operation button 7803 can be freely configured by the operating system built into the personal digital assistant 7800.

Furthermore, the application can be launched by touching the icon 7804 displayed on the display unit 7001 with a finger or the like.

Furthermore, the 7800 portable information terminal is capable of performing short-range wireless communication in accordance with communication standards. For example, by communicating with a wireless communication-enabled headset, it can make hands-free calls.

Furthermore, the portable information terminal 7800 may also have input/output terminals 7802.
If the 802 is present, data can be exchanged directly with other information terminals via a connector. Charging can also be performed via the input/output terminal 7802. Note that the charging operation of the portable information terminal exemplified in this embodiment may be performed by contactless power transmission without using the input/output terminal.

Figure 24(A) shows the exterior of the automobile 7900. Figure 24(B) shows the driver's seat of the automobile 7900. The automobile 7900 includes a body 7901, wheels 7902, windshield 7903, lights 7904, fog lamps 7905, etc.

A display device according to one aspect of the present invention can be used in the display unit of an automobile 7900 or the like. For example, a display device according to one aspect of the present invention can be provided in the display units 7910 to 7917 shown in Figure 24(B).

Display units 7910 and 7911 are installed on the windshield of the automobile. In one aspect of the present invention, by making the electrodes of the display device from a light-transmitting conductive material, a so-called see-through display device can be made, allowing the other side to be seen through. A see-through display device does not obstruct the driver's view when the automobile 7900 is in operation. Therefore, a display device according to one aspect of the present invention can be installed on the windshield of the automobile 7900. When a transistor or the like is provided in the display device, it is preferable to use a light-transmitting transistor, such as an organic transistor using an organic semiconductor material or a transistor using an oxide semiconductor.

The display unit 7912 is located in the pillar section. The display unit 7913 is located in the dashboard section. For example, by displaying images from an imaging means installed on the vehicle body onto the display unit 7912, the field of view obstructed by the pillar can be compensated for. Similarly, the display unit 7
The 913 can compensate for the view obstructed by the dashboard, and the display unit 7914 can compensate for the view obstructed by the doors. In other words, by displaying images from imaging means installed on the outside of the vehicle, blind spots can be compensated for and safety can be enhanced.
Furthermore, by displaying images that fill in the gaps in the unseen areas, safety checks can be performed more naturally and without any sense of unease.

Furthermore, the display unit 7917 is located on the handle. Display unit 7915, display unit 791
6. The display unit 7917 can provide various information such as navigation information, speedometer, tachometer, mileage, fuel level, gear status, and air conditioning settings. The display items and layout displayed on the display unit can be changed as appropriate to suit the user's preferences. The above information can also be displayed on display units 7910 to 7914.

Furthermore, display units 7910 to 7917 can also be used as illumination devices.

The display unit to which a display device according to one aspect of the present invention is applied may be planar. In this case, the display device according to one aspect of the present invention may have a configuration that does not have a curved surface or flexibility.

Figures 24(C) and (D) show an example of digital signage. The digital signage includes a housing 8000, a display unit 8001, and a speaker 8003, etc. It may also include LED lamps, operation keys (including a power switch or operation switch), connection terminals, various sensors, a microphone, etc.

Figure 24(D) shows a digital signage display mounted on a cylindrical column.

The larger the display unit 8001, the more information can be provided at once. Furthermore, a larger display unit 8001 is more eye-catching, which can, for example, enhance the effectiveness of advertising.

Applying a touch panel to the display unit 8001 is preferable because it not only allows images or videos to be displayed on the display unit 8001, but also enables intuitive operation by the user. Furthermore, when used for purposes such as providing route information or traffic information, intuitive operation can enhance usability.

The portable game console shown in Figure 24(E) consists of a casing 8101, a casing 8102, and a display unit 8103.
It includes a display unit 8104, a microphone 8105, a speaker 8106, operation keys 8107, a stylus 8108, and the like.

The portable game console shown in Figure 24(E) has two display units (display unit 8103 and display unit 810
4) It has. The number of display units in an electronic device according to one aspect of the present invention is not limited to two, but may be one or three or more. If an electronic device has multiple display units, it is sufficient that at least one of the display units has a display device according to one aspect of the present invention.

Figure 24(F) shows a notebook personal computer, consisting of a casing 8111 and a display unit 811
2. It includes a keyboard 8113, a pointing device 8114, etc.

A display device according to one embodiment of the present invention can be applied to the display unit 8112.

Figure 25(A) shows the external appearance of the camera 8400 with the viewfinder 8500 attached.

The camera 8400 includes a housing 8401, a display unit 8402, operation buttons 8403, a shutter button 8404, and the like. The camera 8400 is also fitted with a detachable lens 8406.

Here, the camera 8400 is configured so that the lens 8406 can be removed from the housing 8401 and replaced, but the lens 8406 and the housing may also be integrated.

The camera 8400 can take an image by pressing the shutter button 8404. Additionally, the display unit 8402 functions as a touch panel, and images can also be taken by touching the display unit 8402.

The housing 8401 of the camera 8400 has a mount with electrodes, and the viewfinder 850
In addition to the above, a strobe light or similar device can be connected.

The viewfinder 8500 includes a housing 8501, a display unit 8502, buttons 8503, etc.

The housing 8501 has a mount that engages with the mount of the camera 8400, allowing the viewfinder 8500 to be attached to the camera 8400. The mount also has electrodes, which allow images and other data received from the camera 8400 to be displayed on the display unit 8502.

Button 8503 functions as a power button. Button 8503 can be used to switch the display on and off of the display unit 8502.

A display device according to one aspect of the present invention can be applied to the display unit 8402 of the camera 8400 and the display unit 8502 of the viewfinder 8500.

In Figure 25(A), the camera 8400 and the viewfinder 8500 are shown as separate electronic devices and are configured to be detachable. However, the camera 8400's housing 8401 may also have a viewfinder equipped with a display device according to one aspect of the present invention built into it.

Figure 25(B) shows the external appearance of the head-mounted display 8200.

The head-mounted display 8200 consists of a mounting section 8201, a lens 8202, and a main body 82
03. It includes a display unit 8204, a cable 8205, etc. A battery 8206 is also built into the mounting unit 8201.

Cable 8205 supplies power from battery 8206 to main unit 8203. Main unit 82
Unit 03 is equipped with a wireless receiver and can display received image data and other video information on the display unit 8204. In addition, a camera provided on the main unit 8203 captures the movement of the user's eyeballs and eyelids, and by calculating the coordinates of the user's viewpoint based on that information, the user's viewpoint can be used as an input means.

Furthermore, the attachment portion 8201 may be provided with multiple electrodes in a position that touches the user. The main body 8203 detects the current flowing through the electrodes in accordance with the movement of the user's eyeballs,
It may also have a function to recognize the user's gaze. Furthermore, it may have a function to monitor the user's pulse by detecting the current flowing through the electrode. Also, the attachment part 820
1 may have various sensors such as a temperature sensor, a pressure sensor, and an acceleration sensor, and may also have a function to display the user's biological information on the display unit 8204. Furthermore, it may detect the user's head movements and change the image displayed on the display unit 8204 in accordance with those movements.

A display device according to one embodiment of the present invention can be applied to the display unit 8204.

Figures 25(C) and (D) show the external appearance of the head-mounted display 8300.

The head-mounted display 8300 includes a housing 8301, two display units 8302, operation buttons 8303, and a band-shaped fastener 8304.

The head-mounted display 8300 has two display units in addition to the functions of the head-mounted display 8200.

Having two display units 8302 allows the user to view one display unit per eye. This enables the display of high-resolution images even when performing 3D displays using parallax. Furthermore, the display units 8302 are curved in an arc shape with the user's eye as the approximate center. This ensures that the distance from the user's eye to the display surface of the display unit remains constant, allowing the user to see a more natural image. In addition, even if the brightness or chromaticity of the light from the display unit changes depending on the viewing angle, the user's eye is positioned in the direction of the normal to the display surface of the display unit, so this effect can be practically ignored, resulting in a more realistic image.

The operation button 8303 has functions such as a power button. The device may also have other buttons besides the operation button 8303.

Furthermore, as shown in Figure 25(E), a lens 8305 may be provided between the display unit 8302 and the user's eye position. The lens 8305 allows the user to view the display unit 8302 in a magnified manner, thereby enhancing the sense of realism. In this case, as shown in Figure 25(E), a dial 8306 may be provided to change the position of the lens for diopter adjustment.

A display device according to one embodiment of the present invention can be applied to the display unit 8302. Because the display device according to one embodiment of the present invention has extremely high resolution, even when magnified using the lens 8305 as shown in Figure 25(E), the user cannot see the pixels, and a more realistic image can be displayed.

Figures 26(A) to 26(C) show an example where there is one display unit 8302. This configuration allows for a reduction in the number of parts.

The display unit 8302 can display two images side-by-side in two regions, one for the right eye and the other for the left eye. This allows for the display of stereoscopic images using binocular parallax.

Alternatively, a single image visible to both eyes may be displayed across the entire area of the display unit 8302. This makes it possible to display a panoramic image across both ends of the field of view.
It feels more real.

Also, as shown in Figure 26(C), a lens 8305 may be provided. The display unit 8302 has,
The two images may be displayed side by side, or a single image may be displayed on the display unit 8302, allowing the same image to be viewed with both eyes via the lens 8305.

This embodiment can be implemented in appropriate combination with other embodiments described herein, at least in part.

GL Scan line SL Signal line V0 Wiring ANODE Current supply line M1 Transistor M2 Transistor M3 Transistor M4 Transistor M5 Transistor MC Capacitor element EL Light-emitting element CATHODE Common wiring 100 Transistor 102 Substrate 104 Insulating layer 106 Conductive layer 108 Oxide semiconductor layer 110 Insulating layer 110t Film thickness 104t Film thickness 112 Metal oxide layer 116 Insulating layer 108i Channel region 108s Source region 108d Drain region 141a Aperture 141b Aperture 120a Conductive layer 120b Conductive layer PIX Pixel PIX_A Pixel PIX_B Pixel PIX_C Pixel PIX_D Pixel PIX_E Pixel PIX_F Pixel PIX_UL Pixel PIX_UR Pixel PIX_LL Pixel PIX_LR Pixel SUB Substrate 151 Conductive layer 152 Conductive layer 153 Conductive layer 154 Insulating layer 161 Oxide semiconductor layer 162 Oxide semiconductor layer 163 Insulating layer 171 Metal oxide layer 172 Metal oxide layer 173 Metal oxide layer 174 Insulating layer 181 Conductive layer 182 Conductive layer 183 Conductive layer 184 Conductive layer 185 Conductive layer 186 Insulating layer 187 Insulating layer 188 Insulating layer 190 Aperture GL_LC Scan line GL_EL Scan line SL_LC Signal line SL_EL Signal line M6 Transistor LC Liquid crystal element 191 Layer 192 Electrode 193 Aperture 10 Display device 11 Pixel section 12 Scan line driving circuit 13 Signal line driving circuit 15 Terminal section 16a Wiring 16b Wiring GL1 Scan line GL2 Scan line GL3 Scan line V1 Wiring 201 Substrate 202 Substrate 211 Insulating layer 212 Insulating layer 213 Insulating layer 214 Insulating layer 215 Spacer 216 Insulating layer 217 Insulating layer 218 Insulating layer 220 Adhesive layer 221 Insulating layer 222 EL layer 223 Electrode 224 Optical adjustment layer 225 Pixel electrode 230a Structure 230b Structure 231 Light-shielding layer 232 Coloring layer 242 FPC
243 Connection layer 250 Space 251 Transistor 252 Transistor 253 Capacitive element 254 Light-emitting element 255 Transistor 260 Encapsulating material 261 Adhesive layer 262 Adhesive layer 271 Semiconductor layer 272 Conductive layer 273 Conductive layer 274 Conductive layer 275 Conductive layer 276 Insulating layer 291 Conductive layer 292 Conductive layer 293 Conductive layer 294 Insulating layer 295 Adhesive layer 296 Substrate 297 FPC
298 Connection layer 299 Terminal section 301 Fabricated substrate 303 Release layer 305 Layer to be released 307 Adhesive layer 321 Fabricated substrate 323 Release layer 325 Layer to be released 331 Substrate 333 Adhesive layer 341 Substrate 343 Adhesive layer 351 Area 7000 Display section 7001 Display section 7100 Mobile phone 7101 Housing 7103 Operation buttons 7104 External connection port 7105 Speaker 7106 Microphone 7107 Camera 7110 Mobile phone 7200 Portable information terminal 7201 Housing 7202 Operation buttons 7203 Information 7210 Portable information terminal 7300 Television device 7301 Housing 7303 Stand 7311 Remote control unit 7400 Lighting device 7401 Base section 7403 Operation switch 7411 Light-emitting section 7500 Personal Information Terminal 7501 Housing 7502 Components 7503 Operation Buttons 7600 Personal Information Terminal 7601 Housing 7602 Hinge 7650 Personal Information Terminal 7651 Non-display Unit 7700 Personal Information Terminal 7701 Housing 7703a Button 7703b Button 7704a Speaker 7704b Speaker 7705 External Connection Port 7706 Microphone 7709 Battery 7800 Personal Information Terminal 7801 Band 7802 Input/Output Terminal 7803 Operation Buttons 7804 Icon 7805 Battery 7900 Automobile 7901 Body 7902 Wheels 7903 Windshield 7904 Lights 7905 Fog Lamps 7910 Display Unit 7911 Display Unit 7912 Display Unit 7913 Display Unit 7914 Display Unit 7915 Display unit 7916 Display unit 7917 Display unit 8000 Housing 8001 Display unit 8003 Speaker 8101 Housing 8102 Housing 8103 Display unit 8104 Display unit 8105 Microphone 8106 Speaker 8107 Operation keys 8108 Stylus 8111 Housing 8112 Display unit 8113 Keyboard 8114 Pointing device 8200 Head-mounted display 8201 Mounting part 8202 Lens 8203 Main unit 8204 Display unit 8205 Cable 8206 Battery 8300 Head-mounted display 8301 Housing 8302 Display unit 8303 Operation buttons 8304 Fixing device 8305 Lens 8306 Dial 8400 Camera 8401 Housing 8402 Display unit 8403 Operation buttons 8404 Shutter button 8406, Lens 8500, Viewfinder 8501, Body 8502, Display unit 8503, Buttons

Claims (4)

Each pixel has a first to third transistor, a light-emitting element, a signal line, wiring, and a current supply line.
An image signal is input to the aforementioned signal line.
A potential corresponding to the image signal is input to the gate of the second transistor via the first transistor.
The second transistor has the function of controlling the current supplied from the current supply line to the light-emitting element according to the potential,
Either the source or the drain of the third transistor is electrically connected to the wiring.
The source or drain of the third transistor is a semiconductor device electrically connected to the pixel electrode of the light-emitting element,
A first conductive layer having a region disposed on a substrate and functioning as a current supply line,
A first semiconductor layer having a channel formation region of the first transistor,
A second semiconductor layer having a region positioned above the first conductive layer and having a channel formation region for the second transistor and a channel formation region for the third transistor,
A second conductive layer having a region positioned above the first semiconductor layer and functioning as the gate of the first transistor,
A third conductive layer having a region positioned above the second semiconductor layer and functioning as the gate of the second transistor,
A fourth conductive layer having a region positioned above the first conductive layer and electrically connected to the first conductive layer,
A fifth conductive layer having a region positioned above the fourth conductive layer and electrically connected to the fourth conductive layer,
A sixth conductive layer having a region positioned above the second semiconductor layer and electrically connected to the second semiconductor layer,
A seventh conductive layer having the function of a signal line,
The present invention comprises an eighth conductive layer having a region located above the second semiconductor layer and functioning as wiring,
Each of the fifth conductive layer, the sixth conductive layer, the seventh conductive layer, and the eighth conductive layer has a region that is in contact with the upper surface of one of the first insulating layers.
The sixth conductive layer is electrically connected to the pixel electrode of the light-emitting element,
The first conductive layer has a region that overlaps with the third conductive layer via the second semiconductor layer.
Semiconductor equipment. Each pixel has a first to third transistor, a light-emitting element, a signal line, wiring, and a current supply line.
An image signal is input to the aforementioned signal line.
A potential corresponding to the image signal is input to the gate of the second transistor via the first transistor.
The second transistor has the function of controlling the current supplied from the current supply line to the light-emitting element according to the potential,
Either the source or the drain of the third transistor is electrically connected to the wiring.
The source or drain of the third transistor is a semiconductor device electrically connected to the pixel electrode of the light-emitting element,
A first conductive layer having a region disposed on a substrate and functioning as a current supply line,
A first semiconductor layer having a channel formation region of the first transistor,
A second semiconductor layer having a region positioned above the first conductive layer and having a channel formation region for the second transistor and a channel formation region for the third transistor,
A second conductive layer having a region positioned above the first semiconductor layer and functioning as the gate of the first transistor,
A third conductive layer having a region positioned above the second semiconductor layer and functioning as the gate of the second transistor,
A fourth conductive layer having a region positioned above the first conductive layer and electrically connected to the first conductive layer,
A fifth conductive layer having a region positioned above the fourth conductive layer and electrically connected to the fourth conductive layer,
A sixth conductive layer having a region positioned above the second semiconductor layer and electrically connected to the second semiconductor layer,
A seventh conductive layer having the function of a signal line,
The present invention comprises an eighth conductive layer having a region located above the second semiconductor layer and functioning as wiring,
Each of the fifth conductive layer, the sixth conductive layer, the seventh conductive layer, and the eighth conductive layer has a region that is in contact with the upper surface of one of the first insulating layers.
The sixth conductive layer is electrically connected to the pixel electrode of the light-emitting element,
The channel formation region of the first transistor does not overlap with the first conductive layer.
The first conductive layer has a region that overlaps with the third conductive layer via the second semiconductor layer.
Semiconductor equipment. Each pixel has a first to third transistor, a light-emitting element, a signal line, wiring, and a current supply line.
An image signal is input to the aforementioned signal line.
A potential corresponding to the image signal is input to the gate of the second transistor via the first transistor.
The second transistor has the function of controlling the current supplied from the current supply line to the light-emitting element according to the potential,
Either the source or the drain of the third transistor is always in electrical contact with the wiring.
The source or drain of the third transistor is a semiconductor device in which the other is always in electrical contact with the pixel electrode of the light-emitting element,
A first conductive layer having a region disposed on a substrate and functioning as a current supply line,
A first semiconductor layer having a channel formation region of the first transistor,
A second semiconductor layer having a region positioned above the first conductive layer and having a channel formation region for the second transistor and a channel formation region for the third transistor,
A second conductive layer having a region positioned above the first semiconductor layer and functioning as the gate of the first transistor,
A third conductive layer having a region positioned above the second semiconductor layer and functioning as the gate of the second transistor,
A fourth conductive layer having a region positioned above the first conductive layer and always being electrically connected to the first conductive layer,
A fifth conductive layer having a region positioned above the fourth conductive layer and always being electrically connected to the fourth conductive layer,
A sixth conductive layer having a region positioned above the second semiconductor layer and always being electrically connected to the second semiconductor layer,
A seventh conductive layer having the function of a signal line,
The present invention comprises an eighth conductive layer having a region located above the second semiconductor layer and functioning as wiring,
Each of the fifth conductive layer, the sixth conductive layer, the seventh conductive layer, and the eighth conductive layer has a region that is in contact with the upper surface of one of the first insulating layers.
The sixth conductive layer is always in electrical contact with the pixel electrodes of the light-emitting element.
The first conductive layer has a region that overlaps with the third conductive layer via the second semiconductor layer.
Semiconductor equipment. Each pixel has a first to third transistor, a light-emitting element, a signal line, wiring, and a current supply line.
An image signal is input to the aforementioned signal line.
A potential corresponding to the image signal is input to the gate of the second transistor via the first transistor.
The second transistor has the function of controlling the current supplied from the current supply line to the light-emitting element according to the potential,
Either the source or the drain of the third transistor is always in electrical contact with the wiring.
The source or drain of the third transistor is a semiconductor device in which the other is always in electrical contact with the pixel electrode of the light-emitting element,
A first conductive layer having a region disposed on a substrate and functioning as a current supply line,
A first semiconductor layer having a channel formation region of the first transistor,
A second semiconductor layer having a region positioned above the first conductive layer and having a channel formation region for the second transistor and a channel formation region for the third transistor,
A second conductive layer having a region positioned above the first semiconductor layer and functioning as the gate of the first transistor,
A third conductive layer having a region positioned above the second semiconductor layer and functioning as the gate of the second transistor,
A fourth conductive layer having a region positioned above the first conductive layer and always being electrically connected to the first conductive layer,
A fifth conductive layer having a region positioned above the fourth conductive layer and always being electrically connected to the fourth conductive layer,
A sixth conductive layer having a region positioned above the second semiconductor layer and always being electrically connected to the second semiconductor layer,
A seventh conductive layer having the function of a signal line,
The present invention comprises an eighth conductive layer having a region located above the second semiconductor layer and functioning as wiring,
Each of the fifth conductive layer, the sixth conductive layer, the seventh conductive layer, and the eighth conductive layer has a region that is in contact with the upper surface of one of the first insulating layers.
The sixth conductive layer is always in electrical contact with the pixel electrodes of the light-emitting element.
The channel formation region of the first transistor does not overlap with the first conductive layer.
The first conductive layer has a region that overlaps with the third conductive layer via the second semiconductor layer.
Semiconductor equipment.