JP6034048B2 - Display device, electronic equipment - Google Patents

Description

The present invention relates to a display device, a method for manufacturing the display device, and an electronic device.

The driving method of a display device such as a liquid crystal display device or an EL (Electro Luminescence) display device can be roughly classified into a passive matrix method and an active matrix method. Among them, the active matrix method can be widely used for image displays such as television receivers and mobile phones because it can reduce power consumption, increase definition, and increase the size of the substrate compared to the passive matrix method. Has been.

A panel to which an active matrix system is applied as a driving system has been increased in size and definition, and a driving circuit for controlling a driving state of an image display unit is also required to have high performance. For example, a high-performance semiconductor integrated circuit (hereinafter also referred to as an integrated circuit) in which a driver circuit is formed using a material with extremely high mobility such as a single crystal silicon substrate and sealed with resin or the like is manufactured. A technique of mounting the integrated circuit on a substrate on which an image display unit is formed using a COG (Chip on Glass) method or a TAB (Tape Automated Bonding) method is employed (for example, Patent Document 1 regarding the COG method). See).

In the COG method and the TAB method, the integrated circuit is installed in the vicinity of the image display unit in the vicinity of the image display unit in order to minimize the wiring routing distance between the drive circuit included in the integrated circuit and the image display unit. . In the display device, an area around the image display unit that does not function as an image display unit because an integrated circuit is installed is called a “frame portion” or the like.

In recent years, the frame of the display device has been installed from the viewpoint of increasing the design of the display device by installing a larger-sized image display unit in the housing (that is, the product can be downsized while maintaining the size of the image display unit). How to make the part small (so-called narrow frame) is positioned as one of the important factors in designing the product.

In addition, a large display device such as an electronic signboard employs a usage method in which a plurality of display devices are arranged side by side and used as a single display (also referred to as a multi-display). In this case, in order for the viewer to recognize a plurality of display devices as if they were a single display device, the frame portion of each display device is made as small as possible, and the image display units of adjacent display devices are brought as close as possible. It is hoped that.

As a method of achieving a narrow frame of the display device, for example, as in Patent Document 2, an integrated circuit is installed on the back side of the substrate (that is, the surface on which the image display unit is not formed), and the image display unit side A technique for electrically connecting a wiring to an integrated circuit in a folded manner is disclosed.

JP 2003-255386 A JP 2000-98417 A

However, when an integrated circuit is installed on the back side of the substrate using the above-described method, the distance between wirings that electrically connect the integrated circuit and the image display unit becomes long, which causes a decrease in the performance of the display device.

In addition, since the wiring portion is exposed, the wiring portion may be altered depending on the installation environment of the display device, and the display portion may be deteriorated (for example, disconnection) due to external load being applied to the display device. It cannot be said that it is a preferable structure also from a viewpoint of property.

In view of the above problems, an object of the present invention is to provide a display device with a small frame size, high performance, and high reliability.

Another object is to provide a method for manufacturing the above display device.

Another object is to provide a high-value-added electronic device including the above-described display device.

By using a single crystal semiconductor film separated from a single crystal semiconductor substrate as a semiconductor film of a transistor included in the driver circuit, the driver circuit has a thin film structure with high driving performance. The image display unit is arranged on the drive circuit so that at least a portion thereof overlaps the drive circuit.

In the COG method and the TAB method, when an integrated circuit including a driving circuit is overlaid on the image display unit, a part of the display image is blocked by the integrated circuit, and thus a position close to the image display unit (that is, the outer periphery of the image display unit). It is necessary to install an integrated circuit on the outside. In this method, at least a frame portion larger than the size of the integrated circuit (including the size of the resin that seals the drive circuit and the like in addition to the size of the drive circuit) is generated in the display device.

On the other hand, since the display device has the above-described structure, the drive circuit and the image display unit can be overlapped to reduce or eliminate the drive circuit from the image display unit, thereby reducing the size of the frame portion. .

In addition, in order to suppress a decrease in performance of the drive circuit, at least a part of the wiring that electrically connects the drive circuit and the pixel display portion overlaps with the image display portion.

In the case of using the COG method or the TAB method, there is a considerable gap between the integrated circuit and the image display unit, and the wiring is routed across the gap in the surface direction of the substrate to electrically connect the integrated circuit and the image display unit. Since it is necessary to connect, the wiring routing distance becomes long.

On the other hand, since the display device has the above-described structure, the wiring can be routed at a position overlapping the drive circuit or the image display unit, and the drive circuit and the image display unit can be electrically connected. It can be very short, and the performance degradation of the display device can be suppressed.

In addition, by using the display device described above for various electronic devices, it is possible to reduce the size of the product while maintaining the size of the image display portion, and to improve the design of the display device. Can be increased.

That is, according to one embodiment of the present invention, a base substrate, a scan line driver circuit and a signal line driver circuit over the base substrate, a first interlayer film covering the scan line driver circuit and the signal line driver circuit, and a first interlayer A wiring provided on the film and electrically connected to the scanning line driving circuit and the signal line driving circuit, a second interlayer film covering the wiring, and a second interlayer film provided on the second interlayer film, and driving the scanning line by the wiring An image display unit that is electrically connected to the circuit and the signal line driver circuit and includes a plurality of pixels in a matrix, and at least one of the scan line driver circuit and the signal line driver circuit overlaps the image display unit, The wiring is at least partially overlapped with the image display portion, and an active layer of a transistor included in the scan line driver circuit and the signal line driver circuit is formed using a single crystal semiconductor thin film separated from the single crystal semiconductor substrate. You A display device.

As described above, the display device is electrically connected by the wiring sandwiched between the first interlayer film and the second interlayer film so that at least one of the scanning line driving circuit and the signal line driving circuit overlaps the image display unit. By doing so, the size of the frame portion can be reduced.

In one embodiment of the present invention, a base substrate, a scan line driver circuit and a signal line driver circuit over the base substrate, a first interlayer film covering the scan line driver circuit and the signal line driver circuit, and a first interlayer A wiring provided on the film and electrically connected to the scanning line driving circuit and the signal line driving circuit, a second interlayer film covering the wiring, and a second interlayer film provided on the second interlayer film, and driving the scanning line by the wiring And an image display unit that is electrically connected to the circuit and the signal line driver circuit and includes a plurality of pixels in a matrix, and both the scan line driver circuit and the signal line driver circuit overlap with the image display unit, An active layer of a transistor included in a driver circuit and a signal line driver circuit is formed using a single crystal semiconductor thin film separated from a single crystal semiconductor substrate.

The display device is electrically connected by the wiring sandwiched between the first interlayer film and the second interlayer film as described above so that both the scanning line driving circuit and the signal line driving circuit overlap with the image display unit. Thus, the size of the frame portion can be further reduced.

Note that in the above display device, the size of the frame portion can be further reduced by adopting a structure in which both the scanning line driving circuit and the signal line driving circuit are located inside the peripheral end portion of the image display portion. .

Further, in the above-described display device, the size of the frame portion can be further reduced by providing a structure in which all of the wiring is provided at a position overlapping the image display unit.

Then, by using the display device with the reduced frame size as the display unit of the electronic device, the size of the display unit can be increased without increasing the housing size of the electronic device. Can be added value. In addition, since the screen size can be increased without changing the housing size, the display device can be reduced in weight.

In addition, a substrate that transmits 80% or more of light having a wavelength of 300 nm to 700 nm is used as a base substrate of a display device, and a plurality of the display devices are installed so that an image display unit and a frame portion overlap each other in adjacent display devices. As a result, it is difficult to understand the joint (that is, the frame portion) of the display unit, and a multi-display that can be recognized as a single display device can be obtained.

With the structure in which the drive circuit included in the display device and the image display portion overlap, the protrusion of the drive circuit from the image display portion can be reduced, so that the size of the frame portion can be reduced.

Since the wiring that electrically connects the drive circuit and the pixel display unit overlaps with the image display unit, the wiring can be formed without protruding from the image display unit, so the wiring routing distance can be shortened, and the performance of the drive circuit Reduction can be suppressed.

In addition, by using the display device described above for various electronic devices, it is possible to reduce the size of the product while maintaining the size of the image display portion, and to improve the design of the display device. Can be increased.

FIG. 6 illustrates a structure of a display device. 4A and 4B illustrate a method for manufacturing a display device. 4A and 4B illustrate a method for manufacturing a display device. FIG. 6 illustrates a structure of a display device. An example of an electronic device using a display device.

Hereinafter, embodiments of the invention disclosed in this specification will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it is easily understood by those skilled in the art that modes and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below.

Note that in the embodiments described below, the same portions or portions having similar functions are denoted by the same reference numerals in different drawings, and description thereof is not repeated.

In addition, the position, size, range, and the like of each component illustrated in the drawings and the like may not represent the actual position, size, range, or the like for easy understanding. Therefore, the disclosed invention is not necessarily limited to the position, size, range, or the like disclosed in the drawings and the like.

In addition, ordinal numbers such as “first”, “second”, and “third” in this specification and the like are added to avoid confusion between components, and are not limited numerically. To do.

Further, in this specification and the like, the terms “upper” and “lower” do not limit that the positional relationship between the constituent elements is “directly above” or “directly below”. For example, if the expression “B on A” is used, an expression including another component between A and B is not excluded.

In this specification and the like, a process in which a film formed on a substrate or a part of the substrate is transferred to another substrate (also referred to as transposition) is referred to as “transposition” or “transposition process”. .

(Embodiment 1)
In this embodiment, an example of a structure of the display device is described with reference to FIGS. 1A to 1C, and an example of a method for manufacturing the display device is described with reference to FIGS.

<Configuration example of display device>
As an example of a display device, in this embodiment, a voltage is applied to a liquid crystal material sandwiched between a pair of electrodes, and a display device 100 that displays an image using light from the outside (also referred to as a reflective display device). 1) will be described with reference to FIG. FIG. 1A is a plan view of a display device. FIG. 1B is a cross-sectional view of the A1-A2 portion of FIG. Since it is difficult to describe all the structure of the circuit layer in the A1-A2 cross section, FIG. 1B describes the driver circuit portion, the image display portion, and the external wiring connection portion. In FIG. 1A, some components (for example, the counter substrate 138) are not illustrated in order to facilitate understanding of the positions of the components of the display device 100.

As shown in FIG. 1A, the display device 100 includes a circuit layer 180 including a scan line driver circuit 150, a signal line driver circuit 152, and an image display portion 154 formed over a base substrate 102, and the image display portion 154. A counter substrate 138 (not shown) is attached to the base substrate 102 with a sealing material 136 provided around the substrate. An external wiring 172 for supplying a power supply voltage to the components provided in the circuit layer is connected to the base substrate 102 via a conductive material 170.

As shown in FIG. 1B, the circuit layer 180 includes a first circuit layer 156 in which at least the scanning line driver circuit 150 and the signal line driver circuit 152 are formed, and a second circuit in which at least the image display unit 154 is formed. A circuit layer 160 is included. Note that in FIG. 1B, only the scan line driver circuit 150 is illustrated in the first circuit layer 156, but the signal line driver circuit 152 is also included in the first circuit layer 156.

The scanning line driver circuit 150 and signal line driver circuit 152 included in the first circuit layer 156 and the image display unit 154 included in the second circuit layer 160 are actually various elements (for example, thin film transistors and capacitors). In FIG. 1B, the transistor 158 used as a component of the scan line driver circuit 150 is described in the first circuit layer 156, and the transistor 162 used as a component of the image display portion is shown in FIG. 2 in the circuit layer 160.

The transistor 158 included in the scan line driver circuit 150 (and the signal line driver circuit 152) includes the insulating film 104 formed over the base substrate 102, the semiconductor film 106 formed over the insulating film 104, the insulating film 104, and the semiconductor. A conductive film 108 which is formed over the film 106 and functions as a source line (also referred to as a source electrode) or a drain line (also expressed as a drain electrode) of the transistor 158, and the semiconductor film 106 and the conductive film 108. The insulating film 110 which functions as a gate insulating film of the transistor 158 and the conductive film 112 which is formed at a position overlapping the semiconductor film 106 with the insulating film 110 interposed therebetween and which functions as the gate electrode of the transistor 158 are provided. The transistor 158 is covered with a first interlayer film 114, and a first circuit layer 156 is formed.

The transistor 158 is a constituent element of the scanning line driver circuit 150 and the signal line driver circuit 152, and a higher driving performance is required as the display device is increased in size and definition. Therefore, it is not appropriate to use a semiconductor film with low mobility such as amorphous silicon as the semiconductor film 106 of the transistor 158 (it can also be expressed as an active layer of the transistor 158).

In order to improve the driving performance of the transistor, there is a method of forming a transistor on a single crystal semiconductor substrate (for example, a single crystal silicon substrate). However, when the method is used, a display device becomes very expensive. In particular, when the display device is increased in size, it is difficult to say that it is a realistic method.

In view of the above points, in the display device described in this embodiment, the semiconductor film (also referred to as an active layer) of the transistor 158 is formed using a single crystal semiconductor thin film separated from a single crystal semiconductor substrate. One of them.

As will be described later, a single crystal semiconductor thin film is formed by attaching a single crystal semiconductor substrate having an embrittled region therein to another substrate (herein referred to as a support substrate), and then from the support substrate to the single crystal semiconductor substrate. By separating the above, a single crystal semiconductor thin film which is a part of the single crystal semiconductor substrate can be formed over the supporting substrate. Therefore, even when the base substrate 102 has a very large size, a display device is formed by forming the above-described single crystal semiconductor thin film in a region where the scan line driver circuit 150 and the signal line driver circuit 152 are formed over the base substrate 102. It can cope with larger size.

Note that in the case where a single crystal semiconductor thin film separated from a single crystal semiconductor substrate is used as the semiconductor layer 106 as described above, the thickness of the scan line driver circuit 150 or the signal line driver circuit 152 can be extremely reduced; By forming a planarization film over the circuit 150 and the signal line driver circuit 152 to reduce the surface unevenness, the image display portion 154 can be easily formed at a position overlapping the scanning line driver circuit 150 and the signal line driver circuit 152. .

Taking advantage of the above features, the image display unit 154 is arranged on the drive circuit so as to overlap with at least a part of the scanning line drive circuit 150 and the signal line drive circuit 152, so that the size of the frame portion of the display device 100 can be obtained. Can be greatly reduced.

Note that since the scan line driver circuit 150 and the signal line driver circuit 152 are provided at positions overlapping the image display portion 154, in the case of a reflective display device described in this embodiment, a video image of the image display portion 154 is provided. Is not blocked by the scanning line driving circuit 150 and the signal line driving circuit 152. Further, even when this embodiment is applied to a display device using light irradiated from the substrate 102 side (which can also be expressed as a transmissive display device or a transflective display device), the line widths of various conductive films and wirings Even if the scanning line driver circuit 150 and the signal line driver circuit 152 overlap with the image display unit 154 by using a light-transmitting conductive film for various conductive films and wirings that reduce the transmission region, An image display can be obtained.

Further, since the transistor 158 included in the scan line driver circuit 150 and the signal line driver circuit 152 has a structure covered with the base substrate 102, the second circuit layer 160, and the like, a factor that adversely affects the transistor 158 (for example, It can be said that the structure effectively suppresses intrusion of moisture and the like.

On the first circuit layer 156, a second circuit layer 160 in which at least the image display portion 154 is formed is formed with the second interlayer film 116 and the insulating film 118 interposed therebetween.

The second interlayer film 116 planarizes a step generated by the formation of the first circuit layer 156 (also referred to as formation of the scanning line driver circuit 150 and the signal line driver circuit 152), and the scanning line driver circuit 150 and the signal are formed. This has the effect of facilitating the formation of the image display unit 154 in a region overlapping with the line driving circuit 152.

The insulating film 118 has an effect of suppressing entry of impurities such as moisture that can adversely affect the transistor 158 from the outside. In addition, impurities in the first circuit layer 156 (for example, hydrogen present in the first circuit layer 156 or moisture present in the insulating layer 116) diffuse into the second circuit layer 160. There is an effect to suppress.

The transistor 162 included in the image display portion 154 includes a base film 120 formed over the insulating film 118, a conductive film 122 formed over the base film 120 and serving as a gate electrode of the transistor 162, the base film 120, and the conductive film. An insulating film 124 which functions as a gate insulating film of the transistor 162, a semiconductor film 126 formed over the insulating film 124, and an insulating film 124 and a semiconductor film 126. The conductive film 128 functions as a source line (also expressed as a source electrode) or a drain line (also expressed as a drain electrode).

The transistor 162 is covered with the insulating film 130 and the insulating film 132, and the conductive film 134 formed over the insulating film 132 is connected to the conductive film through an opening provided in part of the insulating film 130 and the insulating film 132. 128 is electrically connected to form a second circuit layer 160. Note that the conductive film 134 functions as a pixel electrode in the image display portion 154.

The transistor 162 is a constituent element of the image display portion 154 (which can also be expressed as a switching element of the image display portion 154), and generally does not require driving performance as high as that of the scanning line driver circuit 150 and the signal line driver circuit 152. . Therefore, films of various materials can be used for the semiconductor film 126. In view of increasing the size and definition of the display device 100, the channel formation region formed in the semiconductor film 126 preferably has a mobility of at least 1 [cm ² / Vs]. As the film 126, for example, similarly to the semiconductor film 106, a single crystal semiconductor film or a polycrystalline semiconductor film separated from a single crystal semiconductor substrate can be used. As a material for the semiconductor film, for example, silicon, germanium, silicon germanium, silicon carbide, gallium arsenide, or the like can be used.

Alternatively, an oxide semiconductor can be used as the material of the semiconductor film 126. The semiconductor film 126 using an oxide semiconductor material is in a single crystal state, a polycrystalline (also referred to as polycrystal) state, an amorphous state, or the like.

Preferably, the semiconductor film 126 is a CAAC-OS (C Axis Crystallized Oxide Semiconductor) film.

The CAAC-OS film is not completely single crystal nor completely amorphous. The CAAC-OS film is an oxide semiconductor film with a crystal-amorphous mixed phase structure where crystal parts and amorphous parts are included in an amorphous phase. Note that the crystal part is often large enough to fit in a cube whose one side is less than 100 nm. Further, in the observation image obtained by a transmission electron microscope (TEM), the boundary between the amorphous part and the crystal part included in the CAAC-OS film is not clear. Further, a grain boundary (also referred to as a grain boundary) cannot be confirmed in the CAAC-OS film by TEM. Therefore, in the CAAC-OS film, reduction in electron mobility due to grain boundaries is suppressed.

In the crystal part included in the CAAC-OS film, the c-axis is aligned in a direction parallel to the normal vector of the formation surface of the CAAC-OS film or the normal vector of the surface, and triangular when viewed from the direction perpendicular to the ab plane. It has a shape or hexagonal atomic arrangement, and metal atoms are arranged in layers or metal atoms and oxygen atoms are arranged in layers as viewed from the direction perpendicular to the c-axis. Note that the directions of the a-axis and the b-axis may be different between different crystal parts. In this specification, a simple term “perpendicular” includes a range from 85 ° to 95 °. In addition, a simple term “parallel” includes a range from −5 ° to 5 °.

Note that the distribution of crystal parts in the CAAC-OS film is not necessarily uniform. For example, in the formation process of the CAAC-OS film, when crystal growth is performed from the surface side of the oxide semiconductor film, the ratio of crystal parts in the vicinity of the surface of the oxide semiconductor film is higher in the vicinity of the surface. In addition, when an impurity is added to the CAAC-OS film, the crystal part in a region to which the impurity is added becomes amorphous in some cases.

Since the c-axis of the crystal part included in the CAAC-OS film is aligned in a direction parallel to the normal vector of the formation surface of the CAAC-OS film or the normal vector of the surface, the shape of the CAAC-OS film (formation surface) Depending on the cross-sectional shape of the surface or the cross-sectional shape of the surface). Note that the c-axis direction of the crystal part is parallel to the normal vector of the surface where the CAAC-OS film is formed or the normal vector of the surface. The crystal part is formed by film formation or by performing crystallization treatment such as heat treatment after film formation.

A transistor including a CAAC-OS film can reduce variation in electrical characteristics due to irradiation with visible light or ultraviolet light. Therefore, the transistor has high reliability.

An oxide semiconductor has a large energy gap of 3.0 to 3.5 eV or more, and in a transistor obtained by processing an oxide semiconductor under appropriate conditions, an off-state current is used under temperature conditions (for example, 25 C.), it can be 100 zA (1 × 10 ⁻¹⁹ A) or less, or 10 zA (1 × 10 ⁻²⁰ A) or less, and further 1 zA (1 × 10 ⁻²¹ A) or less. For this reason, a display device with low power consumption can be realized.

On the second circuit layer 160, a counter substrate 138 having a conductive film 140 functioning as a common electrode of the display device 100 on one surface and a color filter 142 formed on the other surface is a second circuit layer. 160 and the conductive film 140 are attached to the base substrate 102 with a sealing material 136 in a state of facing each other. The gap between the bonded base substrate 102 and the counter substrate 138 can be adjusted to the spacer 144, and the liquid crystal material 146 is injected into the gap between the base substrate 102 and the counter substrate 138 formed by the spacer 144. .

Further, the transistor 158 included in the scan line driver circuit 150 (and the signal line driver circuit 152) and the transistor 162 included in the image display portion 154 are formed between the first circuit layer 156 and the second circuit layer 160. At least a portion is electrically connected through a conductive film 148 (also referred to as connection wiring) overlapping with the image display portion.

By setting the formation position of the conductive film 148 to the above-described position, the conductive film 148 can be formed at a position overlapping the first circuit layer 156 and the second circuit layer 160, and the outer peripheral portion (that is, the frame) of the image display portion 154. No need to route part.). For this reason, it can suppress that the frame part of the display apparatus 100 becomes large by the drawing of the electrically conductive film 148.

The display device described in this embodiment has the above structure.

<Method for Manufacturing Display Device>
Next, an example of a manufacturing process of the display device 100 illustrated in FIG. 1 will be described with reference to FIGS.

First, the insulating film 104 and the semiconductor film 106 are formed over the base substrate 102 (see FIG. 1A).

The semiconductor film 106 described in this embodiment and the like is formed using a single crystal semiconductor film obtained by separating part of a single crystal semiconductor substrate. As a method for separating a part of the single crystal semiconductor substrate and forming a single crystal semiconductor thin film over the base substrate 102, for example, a method described in “JP 2008-277789” which is a publicly known document is used. it can. Needless to say, the single crystal semiconductor thin film may be formed over the base substrate 102 by using other known techniques as well as the known literature. Note that the above-described publicly-known documents can be referred to for the formation methods and materials of the insulating film 104 and the semiconductor film 106, and thus the description thereof is omitted here.

Note that the base substrate 102 needs to have at least heat resistance enough to withstand heat treatment performed later. For example, a glass substrate such as barium borosilicate glass or alumino borosilicate glass, a substrate such as a ceramic substrate, a quartz substrate, or a sapphire substrate can be used. Alternatively, a single crystal semiconductor substrate such as silicon or silicon carbide, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, or the like can be used as long as it has an insulating surface.

Next, the conductive film 108 functioning as a source line (also referred to as a source electrode) or a drain line (also referred to as a drain electrode) of the transistor 162 and a gate insulation of the transistor 158 over the insulating film 104 and the semiconductor film 106. An insulating film 110 functioning as a film and a conductive film 112 functioning as a gate electrode of the transistor 158 are formed, so that the transistor 158 is formed. Further, the first circuit layer 156 is formed by forming the first interlayer film 114 over the transistor 158 (see FIG. 2B). Note that in FIG. 2B, only two transistors 158 are formed in the first circuit layer 156; however, in actuality, the scan line driver circuit 150 and the first circuit layer 156 are included in the first circuit layer 156. At least a signal line driver circuit 152 is formed.

Note that although the first circuit layer 156 includes the first interlayer film 114 in this embodiment and the like, at least the scan line driver circuit 150 and the signal line driver circuit 152 are included. If it is a structure, it can be expressed as the first circuit layer 156 without being limited to the structure.

As the conductive film 108, a conductive film is formed over the base substrate 102 and the insulating film 104, a mask is formed over the conductive film by a photolithography method, a printing method, an inkjet method, or the like, and the conductive film is formed using the mask. This is formed by selectively removing a part of the film.

The conductive film used for forming the conductive film 108 is formed by a physical vapor deposition method (PVD: Physical Vapor Deposition) such as a vacuum evaporation method or a sputtering method, or a chemical vapor deposition method (CVD: Chemical Vapor Deposition) such as a plasma CVD method. For example, a metal film containing an element selected from aluminum, chromium, copper, tantalum, titanium, molybdenum, tungsten, or a metal nitride film containing any of the above-described elements (titanium nitride film, molybdenum nitride film, nitriding) (Tungsten film) may be formed as a single layer film or a laminated film. Further, a refractory metal film such as titanium, molybdenum, tungsten or the like or a metal nitride film thereof (titanium nitride film, molybdenum nitride film, tungsten nitride film) on one or both of the lower side or upper side of a metal film such as aluminum or copper. You may use the film | membrane which laminated | stacked. Alternatively, a conductive metal oxide film may be formed. As the conductive metal oxide film, indium oxide (In ₂ O ₃ ), tin oxide (SnO ₂ ), zinc oxide (ZnO), indium tin oxide (In ₂ O ₃ —SnO ₂ , abbreviated as ITO), Indium zinc oxide (In ₂ O ₃ —ZnO) or a metal oxide film containing silicon oxide can be used. Since the conductive metal oxide film easily transmits light in the visible light region, light emitted from the substrate 102 side particularly when the display device 100 is a display device using light irradiated from the substrate 102 side. Is preferable because it is easily transmitted to the image display unit 154 side.

As the insulating film 110, an oxide insulating film having sufficient withstand voltage and insulating property is preferably used. As the insulating film 110, for example, a physical vapor deposition method (PVD) such as a vacuum deposition method or a sputtering method, or a chemical vapor deposition method (CVD: Chemical Vapor Deposition) such as a plasma CVD method is used. Silicon oxide film, silicon oxynitride film, silicon nitride film, silicon nitride oxide film, aluminum oxide film, aluminum nitride film, aluminum oxynitride film, aluminum nitride oxide film, gallium oxide film, yttrium oxide film, lanthanum oxide film, etc. A single layer or a stacked structure may be used. Note that in the case where the insulating film 110 is formed using a plasma CVD method, the film density is higher than that in the case where microwaves are not used by using plasma generated by microwaves (eg, 2.45 GHz microwaves). A high-quality insulating film having a high interface state density and a low interface state density can be formed.

As the insulating film 110, a hafnium oxide film, a hafnium silicate film (HfSi _x O _y x> 0, y> 0)), a hafnium silicate film to which nitrogen is added (HfSiO _x N _y (x> 0, y> 0)) ), A high-k material such as a hafnium aluminate film (HfAl _x O _y (x> 0, y> 0)) may be used as at least part of the insulating film 110. As a result, the gate leakage current can be reduced.

As the conductive film 112, a conductive film is formed over the insulating film 110, a mask is formed over the conductive film by a photolithography method, a printing method, an inkjet method, or the like, and part of the conductive film is formed using the mask. It is formed by selective removal.

The conductive film used for forming the conductive film 112 is, for example, a physical vapor deposition method (PVD) such as a vacuum deposition method or a sputtering method, or a chemical vapor deposition method (CVD: Chemical Vapor Deposition) such as a plasma CVD method. ), A metal film such as a molybdenum film, a titanium film, a tantalum film, a tungsten film, an aluminum film, a copper film, a neodymium film, or a scandium film or a film containing these as a main component is formed in a single layer or a laminated structure. Good. Alternatively, a conductive metal oxide film may be used. The conductive metal oxide film is abbreviated as indium oxide (In ₂ O ₃ ) film, tin oxide (SnO ₂ ) film, zinc oxide (ZnO) film, indium tin oxide (In ₂ O ₃ —SnO ₂ , ITO). In some cases, the conductive film 112 may be formed using a film including silicon oxide or silicon oxide in an indium zinc oxide (In ₂ O ₃ —ZnO) film or a metal oxide film thereof. You can also.

Through the above steps, the transistor 158 included in the scan line driver circuit 150 and the signal line driver circuit 152 can be formed over the base substrate 102.

Note that the first interlayer film 114 over the transistor 158 used for forming the first circuit layer 156 may be formed in consideration of the material and method described in the description of the insulating film 110.

Next, the second interlayer film 116, the insulating film 118, the base film 120, and the image display portion 154, the scanning line driver circuit 150, and the signal line driver circuit 152 are electrically connected to the first interlayer film 114. A conductive film 148 functioning as a wiring to be formed is formed (see FIG. 2C). Note that a wiring 145 used for electrically connecting the external wiring 172 to the scan line driver circuit 150 and the signal line driver circuit 152 in a later step is formed in the step of forming the conductive film 148 (FIG. 2C )reference.).

The second interlayer film 116 mainly has a role as a planarizing layer for reducing a step generated by the formation of the first circuit layer 156. As the second interlayer film 116, for example, an organic resin such as an acrylic resin, a polyimide resin, a polyamide resin, a polyamideimide resin, or an epoxy resin is used for the first circuit layer by using a wet method such as a spin coating method or a printing method. It may be formed by being applied onto 156 and cured by heat treatment or the like. Further, a low dielectric constant material (low-k material), a siloxane resin, PSG (phosphorus glass), BPSG (phosphorus boron glass), or the like can be used. Note that a plurality of films formed using these materials may be stacked. Note that since the above-described organic material often contains a relatively large amount of impurities such as moisture, a film with low water vapor permeability (for example, aluminum oxide or aluminum oxide) is in contact with a film formed using the organic material. A laminated film containing the same may be formed. Note that the first circuit layer 156 is not necessarily provided when the step generated by the formation of the first circuit layer 156 is sufficiently small so as not to adversely affect the formation of the second circuit layer 160.

The insulating film 118 has an effect of suppressing the entry of impurities that may adversely affect the electrical characteristics of the transistor 158 from the outside, and the diffusion of impurities that may adversely affect the electrical characteristics of the transistor 162 from the first circuit layer 156. Has the effect of suppressing the above. Note that the insulating film 118 is not necessarily provided; however, in the case where an oxide semiconductor film is used as the semiconductor film 126 of the second circuit layer 160, if the oxide semiconductor film 126 contains a large amount of hydrogen, oxidation is performed. By combining with a physical semiconductor, a part of hydrogen becomes a donor and an electron which is a carrier is generated, the threshold voltage of the transistor 162 is shifted in the negative direction, the initial characteristic variation of the transistor is increased, the transistor It can be said that it is desirable to provide the insulating film 118 because there is a possibility that problems such as an increase in L length dependency on the electrical characteristics and an increase in electrical characteristics deterioration in the BT stress test may occur.

The insulating film 118 and the base film 120 may be formed in consideration of materials and methods described in the description of the insulating film 110.

Note that in the case where an oxide semiconductor film is used as the semiconductor film 106 included in the transistor 162, the base film 120 is preferably a film from which oxygen is released by heat treatment (hereinafter also referred to as an oxygen supply film). . The reason is described below.

In a transistor in which an oxide semiconductor film is used as the semiconductor film 126, when oxygen vacancies exist in the channel formation region in the semiconductor film 126, charge may be generated due to oxygen vacancies. In general, part of oxygen vacancies in the oxide semiconductor film serves as a donor and emits electrons as carriers. As a result, the threshold voltage of the transistor shifts in the negative direction.

In the case where the base film 120 functions as an oxygen supply film, part of oxygen in the oxygen supply film can be released by heat treatment. Therefore, after forming a semiconductor film 126 described later, the oxygen supply layer is heated to form the semiconductor film 126. Oxygen can be supplied to fill oxygen vacancies in the semiconductor film 126. Thus, the shift of the threshold voltage of the transistor 162 in the negative direction can be suppressed. In particular, it is preferable that an amount of oxygen exceeding the stoichiometric composition ratio is present in the base film 120. For example, when silicon oxide is used as the base film 120, it is preferable to use a silicon oxide film represented by SiO _{2 + α} (where α> 0). Note that a region containing oxygen in excess of the stoichiometric composition ratio (hereinafter sometimes referred to as an oxygen-excess region) may be present in at least a part of the base film 120.

Note that the above-described “film that releases oxygen by heat treatment” means that the amount of released oxygen converted to oxygen atoms in a TDS (Thermal Desorption Spectroscopy) analysis is 1.0. × 10 ¹⁹ atoms / cm ³ or more, preferably 3.0 × 10 ¹⁹ atoms / cm ³ or more, more preferably 1.0 × 702 ⁰ atoms / cm ³ or more, more preferably 3.0 × 702 ⁰ atoms / cm It means ³ or more.

Here, a method for measuring the amount of released oxygen converted into oxygen atoms in TDS analysis will be described below.

The amount of gas released by TDS analysis is proportional to the integral value of the spectrum. For this reason, the amount of gas emission can be calculated from the ratio between the measured integral value of the spectrum and the reference value of the standard sample. The reference value of the standard sample is the ratio of the atomic density to the integral value of the spectrum in a sample having a predetermined atomic density.

For example, the amount of released oxygen molecules (N _O2 ) of the insulating film is obtained by the equation (1) from the TDS analysis result of a silicon wafer containing hydrogen of a predetermined density as a standard sample and the TDS analysis result of the insulating film. Can do. Here, it is assumed that all of the spectra detected when the mass-to-charge ratio (M / z) obtained by TDS analysis is 32 are derived from oxygen molecules. There is CH ₃ OH in addition to M / z of 32, but it is not considered here as it is unlikely to exist. In addition, oxygen molecules containing an oxygen atom with an M / z of 17 and an oxygen atom with an M / z of 18 that are isotopes of oxygen atoms are not considered because their abundance ratio in nature is extremely small.

N _H2 is a value obtained by converting hydrogen molecules desorbed from the standard sample by density. _SH2 is an integral value of a spectrum obtained by TDS of a standard sample. Here, the reference value of the standard sample is N _H2 / SH ₂ . S _O2 is an integral value of a spectrum obtained by TDS analysis of the insulating film. α is a coefficient that affects the spectral intensity in TDS. For details of the expression (1), refer to Japanese Patent Laid-Open No. Hei 6-275697. The oxygen release amount of the insulating film is a silicon wafer containing 1 × 10 ¹⁶ atoms / cm ³ hydrogen atoms as a standard sample using a temperature programmed desorption analyzer EMD-WA1000S / W manufactured by Electronic Science Co., Ltd. Use to measure.

In TDS analysis, part of oxygen is detected as oxygen atoms. The ratio of oxygen molecules to oxygen atoms can be calculated from the ionization rate of oxygen molecules. Note that since the above α includes the ionization rate of oxygen molecules, the amount of released oxygen atoms can be estimated by evaluating the amount of released oxygen molecules.

Note that N _{2 O 2} is the amount of released oxygen molecules. The amount of release when converted to oxygen atoms is twice the amount of release of oxygen molecules.

For the introduction of oxygen into the film, heat treatment in an oxygen atmosphere, ion implantation, ion doping, plasma immersion ion implantation, plasma treatment performed in an atmosphere containing oxygen, or the like can be used.

Note that in the case where oxygen is supplied from the base film 120 to the semiconductor film 126 by heat treatment, oxygen transmission is performed in a lower layer of the base film 120 so that oxygen released from the base film 120 is efficiently supplied to the semiconductor film 126. It is preferable to form a film having a low water vapor permeability (also referred to as moisture permeability) (hereinafter sometimes referred to as a barrier film). For example, the insulating film 118 in contact with the base film 120 may have a structure in which a barrier film such as an aluminum oxide film, an aluminum oxynitride film, or an aluminum nitride oxide film is formed. Note that in the case of using an aluminum oxide film, it is preferable that the film has a high density (a film density of 3.2 g / cm ³ or more, preferably 3.6 g / cm ³ or more).

The conductive film 148 may be formed in consideration of the materials and methods described in the description of the conductive film 108.

Next, the conductive film 122 functioning as the gate electrode of the transistor 162, the insulating film 124 functioning as the gate insulating film of the transistor 162, the semiconductor film 126, and the source line (source electrode) of the transistor 162 can be expressed over the base film 120. ) Or a drain line (also referred to as a drain electrode), a conductive film 128 is formed, and the transistor 162 is formed. Further, the second circuit layer 160 including the image display portion 154 is formed by forming the insulating film 130, the insulating film 132, and the conductive film 134 over the transistor 162 (see FIG. 2D). The conductive film 134 is electrically connected to the transistor 162 through an opening provided in the insulating film 130 and the insulating film 132 and functions as a pixel electrode of the image display portion 154.

In addition, a wiring 129 and a wiring 135 which are used to electrically connect the external wiring 172, the scanning line driver circuit 150, and the signal line driver circuit 152 in a later step are used for forming the conductive film 128 and the conductive film 134, respectively. (See FIG. 2D).

Note that the second circuit layer 160 is not limited to the structure, and can be expressed as the second circuit layer 160 without being limited to the structure as long as the structure includes at least the image display portion 154.

The conductive film 122 may be formed in consideration of the material and method described in the description of the conductive film 112.

Note that in the case where an oxide semiconductor film is used as the semiconductor film 126, a film having a work function larger than that of the film used as the semiconductor film 126 is preferably used on at least a surface in contact with the insulating film 124 of the conductive film 122. The film includes an In—Ga—Zn—O film containing nitrogen, an In—Sn—O film containing nitrogen, an In—Ga—O film containing nitrogen, an In—Zn—O film containing nitrogen, and nitrogen. A metal oxide film containing nitrogen such as an Sn—O film, an In—O film containing nitrogen, or a metal nitride film (InN, SnN, or the like) can be used. These films have a work function of 5 eV (electron volt), preferably 5.5 eV (electron volt) or more, and when the film is used as a gate electrode, the threshold voltage of the electrical characteristics of the transistor is made positive. Thus, a so-called normally-off switching element can be realized.

The insulating film 124 may be formed in consideration of materials and methods described in the description of the insulating film 110.

Note that in the case where an oxide semiconductor film containing indium is used as the semiconductor film 126, when the insulating film 124 and the semiconductor film 126 are in direct contact with each other, indium in the semiconductor film 126 diffuses into the insulating film 124 and the transistor 162 May adversely affect properties. Therefore, a film having a function of suppressing indium diffusion may be formed between the insulating film 124 and the semiconductor film 126. As the film, for example, gallium oxide, zinc gallium oxide, or the like can be used. Further, the insulating film 124 itself may be a film having a function of suppressing indium diffusion.

As the semiconductor film 126, for example, a single crystal semiconductor film separated from a single crystal semiconductor substrate can be used like the semiconductor film 106. Further, a polycrystalline (also referred to as polycrystal) film, a microcrystalline (also referred to as microcrystal) film, or an amorphous film such as silicon, germanium, silicon germanium, silicon carbide, or gallium arsenide is used as a semiconductor film. Also good. These films may be formed using a known technique.

Further, as the semiconductor film 126, an oxide semiconductor film is formed using a sputtering method, an MBE (Molecular Beam Epitaxy) method, a CVD method, a pulse laser deposition method, an ALD (Atomic Layer Deposition) method, or the like, and then a photolithography method. Alternatively, a mask may be formed over the oxide semiconductor film by a printing method, an inkjet method, or the like, and the semiconductor film 126 may be formed by selectively removing part of the oxide semiconductor film using the mask. An oxide semiconductor film can also be used. The oxide semiconductor material film is in a single crystal state, a polycrystalline (also referred to as polycrystal) state, an amorphous state, or the like.

In the case where an oxide semiconductor film is used as the semiconductor film 126, a CAAC-OS (C Axis Aligned Crystalline Oxide Semiconductor) film is preferable.

Note that in the case where a CAAC-OS film is formed as the semiconductor film 126, the following three methods may be used. The first method is a method in which an oxide semiconductor film is formed at a deposition temperature of 200 ° C. to 450 ° C. to obtain a CAAC-OS film. The second method is a method in which after forming an oxide semiconductor film, the film is subjected to heat treatment at 200 ° C. to 700 ° C. to obtain a CAAC-OS film. In the third method, the oxide semiconductor film is divided into two layers, the first oxide semiconductor film is thinly formed, and then heat treatment is performed at 200 ° C. to 700 ° C. to form the first layer film. Is a CAAC-OS film, and a second layer is formed over the film, whereby the first layer crystal is used as a seed crystal and the second oxide semiconductor film is a CAAC-OS film.

The conductive film 128 may be formed in consideration of the material and method described in the description of the conductive film 108.

Note that an insulating film is used to electrically connect the scanning line driver circuit 150 (and the signal line driver circuit 152) included in the first circuit layer 156 and the image display portion 154 included in the second circuit layer 160. 124, the conductive film 128 is formed in a state in which openings are formed in part of the base film 120, the insulating film 118, and the second interlayer film 116 so that the conductive film 148 is exposed.

The insulating film 130 may be formed in consideration of the material and method described in the description of the insulating film 118. The insulating film 132 may be formed in consideration of the material and method described in the second interlayer film 116.

The conductive film 134 functions as a pixel electrode of the image display portion 154. The conductive film 134 may be formed in consideration of the materials and methods described in the description of the conductive film 108.

Next, over the insulating film 132 and the conductive film 134, a counter substrate 138 in which the conductive film 140 that functions as a common electrode of the display device 100 is formed on one surface and the color filter 142 is formed on the other surface is formed on the first substrate. The second circuit layer 160 and the conductive film 140 are attached to the base substrate 102 with a sealing material 136 in a state of facing each other. Note that at the time of bonding, the bonding is performed between the base substrate 102 and the counter substrate 138 in a state where a spacer 144 is sandwiched in order to adjust the gap size between the two. Then, the display device 100 is completed by injecting the liquid crystal material 146 into the gap between the base substrate 102 and the counter substrate 138 formed by the spacer 144 (see FIG. 3A).

The counter substrate 138 may be formed in consideration of materials and methods described in the description of the base substrate 102. The conductive film 140 may be formed in consideration of the materials and methods described in the description of the conductive film 108.

The color filter 142, the spacer 144, and the liquid crystal material 146 are not particularly limited in materials and formation methods, and known techniques can be used. In addition, a known technique can be used as a material and a formation method of the sealing material 136 and a bonding method of the base substrate 102 and the counter substrate 138.

Next, the external wiring 172 is bonded to the wiring 135 electrically connected to the scanning line driver circuit 150 (and the signal line driver circuit 152) included in the first circuit layer 156 using the conductive material 170 (FIG. 3). (See (B).)

Various known materials can be used as the conductive material 170 and the external wiring 172. For example, as the conductive material 170, an anisotropic conductive resin (ACP) or an anisotropic conductive film (ACF: Anisotropic Conductive Film) is used. The external wiring 172 can be a flexible printed circuit (FPC).

Through the above steps, the display device 100 illustrated in FIG. 1 can be formed.

In the light-emitting device, the semiconductor film 106 of the transistor 158 which is a component of the scan line driver circuit 150 and the signal line driver circuit 152 is a thin film transistor formed using a single crystal semiconductor thin film separated from a single crystal semiconductor substrate. , Has high driving ability.

In addition, the scan line driver circuit 150 and the signal line driver circuit 152 are configured using thin film elements (for example, thin film transistors, for example) as described above, so that the first scan line driver circuit 150 and the signal line driver circuit 152 are provided. Since the thickness of the circuit layer 156 can be very thin, the second circuit layer 160 including the image display portion 154 can be formed so as to overlap with the first circuit layer 156.

In addition, a conductive film 148 that electrically connects the image display portion 154 to the scanning line driver circuit 150 and the signal line driver circuit 152 is formed at a position overlapping the image display portion 154.

Therefore, there is no need to install the scanning line driving circuit 150 and the signal line driving circuit 152 around the image display unit 154 in the display device 100, and the image display unit 154, the scanning line driving circuit 150, and the signal line driving circuit 152 are not provided. Since the space for wiring between them can be eliminated, the frame portion of the display device 100 can be greatly reduced.

In addition, since the first circuit layer 156 including the scan line driver circuit 150 and the signal line driver circuit 152 is sandwiched between the base substrate 102 and the second circuit layer 160, the scan line driver circuit 150 and the signal line An impurity (eg, moisture) is difficult to enter from the outside into the transistor 158 which is one of the components of the driver circuit 152. Accordingly, the scan line driver circuit 150 and the signal line driver circuit 152 can have high reliability with stable characteristics over a long period of time.

Note that in the image display portion 154 of the display device 100 in this embodiment, a liquid crystal material is sandwiched between the conductive film 134 included in the circuit layer 180 and the conductive film 140 included in the counter substrate 138 so that a power supply voltage is applied to the electrodes. Although a structure of a so-called liquid crystal display device that displays an image by performing is described, as illustrated in FIG. 4, a partition wall 402 is formed so as to cover an end portion of the conductive film 134, and at least light emitting property is formed over the conductive film 134. A display device including an image display portion having a structure in which an EL layer 404 including a light-emitting layer containing any organic compound is formed, and a conductive film 406 overlapping the conductive film 134 is formed on the EL layer 404 with the EL layer 404 interposed therebetween. It may be 400. Note that the display device 400 in FIG. 4 has the color filter 142 formed on the counter substrate 138, but the color filter 142 is not necessarily provided if a desired video display is possible only with the light emitted from the image display unit. There is no need.

(Embodiment 2)
The semiconductor device disclosed in this specification and the like can be applied to a variety of electronic devices (including game machines). Examples of the electronic device include a television device (also referred to as a television or a television receiver), a monitor for a computer, a camera such as a digital camera or a digital video camera, a digital photo frame, a mobile phone (a mobile phone or a mobile phone). Large-sized game machines such as portable game machines, portable information terminals, sound reproduction apparatuses, and pachinko machines. Examples of electronic devices each including the display device described in the above embodiment will be described below.

FIG. 5A illustrates an example of a portable information terminal 500. A housing 501 is provided with a display portion 502, a speaker 503, a camera 504, a microphone 505, an external connection terminal 506, and the like. Has been. Note that various electronic components (for example, a CPU, an MPU, a memory element, and the like) are incorporated in the housing 501.

By using the display device having the structure described in the above embodiment as the display portion 502 of the information terminal 500, the frame of the information terminal 500 can be extremely small. For this reason, since the size of the display unit 502 can be increased without increasing the size of the housing 501, for example, the screen size is increased while maintaining a shape that a person can hold with one hand, and the information terminal 500 Can add value. Further, since the screen size can be increased without changing the housing size, the information terminal 500 can be reduced in weight.

Note that a communication device may be provided in the information terminal 500 and used as a mobile phone (also referred to as a smartphone).

FIG. 5B illustrates an example of a television device 510, in which a display portion 512 and the like are incorporated in a housing 511 and supported by a stand 513.

By using the display device having the structure described in the above embodiment as the display portion 512 of the television device 510, the frame of the television device can be extremely small. Therefore, since the size of the display portion 512 can be increased without increasing the size of the housing 511, the television device 510 can have high design value and high added value. In addition, since the screen size can be increased without changing the housing size, the television apparatus 510 can be reduced in weight.

The television device 510 can be operated by directly touching an operation button or the like displayed on the display unit 512. Further, it can be performed by an operation switch provided in the housing 511 or a separate remote controller.

The television device 510 includes a receiver, a modem, and the like. General TV broadcasts can be received by a receiver, and connected to a wired or wireless communication network via a modem, so that it can be unidirectional (sender to receiver) or bidirectional (sender and receiver). It is also possible to perform information communication between each other or between recipients).

Note that since the frame portion of the television device 510 including the display device having the structure described in this embodiment is extremely small, a plurality of housings 511 including the display portion 512 are arranged as illustrated in FIG. Even when it is used as the multi-display 520, it is difficult for the viewer to understand the joint of the display unit 512 (that is, the frame portion), so that the viewer can recognize it as a single display device. ing.

In particular, a display device using a substrate that transmits 80% or more of light with a wavelength of 300 nm or more and 700 nm or less as a base substrate is shown in FIG. In addition, it is preferable that the image display unit and the frame portion be installed so as to overlap each other in the adjacent display device. In the display device described in Embodiment 1, a circuit that blocks light, such as a scanning line driver circuit or a signal line driver circuit, is not formed in a portion that does not overlap with the image display portion (that is, a frame portion). Alternatively, since the formed area is extremely small, the display portion 512 is clearly displayed to the viewer even if it overlaps the frame portion of the housing 511, and thus the frame portion between the display devices is completely eliminated. The viewer can recognize the display device as a single display device.

As described above, the application range of the present invention is extremely wide and can be used for electronic devices and information display means in various fields.

  This embodiment can be implemented in appropriate combination with any of the other embodiments.

100 display device 102 base substrate 104 insulating film 106 semiconductor film 108 conductive film 110 insulating film 112 conductive film 114 first interlayer film 116 second interlayer film 118 insulating film 120 base film 122 conductive film 124 insulating film 126 semiconductor film 128 conductive Film 129 Wiring 130 Insulating film 132 Insulating film 134 Conductive film 135 Wiring 136 Sealing material 138 Counter substrate 140 Conductive film 142 Color filter 144 Spacer 145 Wiring 146 Liquid crystal material 148 Conductive film 150 Scan line driving circuit 152 Signal line driving circuit 154 Image display Part 156 first circuit layer 158 transistor 160 second circuit layer 162 transistor 170 conductive material 172 external wiring 180 circuit layer 400 display device 402 partition 404 EL layer 406 conductive film 500 information terminal 501 housing 502 display unit 503 F 504 Camera 505 Microphone 506 External connection terminal 510 Television apparatus 511 Housing 512 Display unit 513 Stand 520 Multi display

Claims (6)

A base substrate;
A scanning line driving circuit and a signal line driving circuit on the base substrate;
A first interlayer film covering the scanning line driving circuit and the signal line driving circuit;
A wiring provided on the first interlayer film and electrically connected to the scanning line driving circuit and the signal line driving circuit;
A second interlayer film covering the wiring;
An image display unit provided on the second interlayer film, and electrically connected to the scanning line driving circuit and the signal line driving circuit by the wiring, and having a plurality of pixels in a matrix,
At least one of the scanning line driving circuit and the signal line driving circuit overlaps with the image display unit;
The wiring is at least partially overlapped with the image display unit,
A display device, wherein an active layer of a transistor included in the scan line driver circuit and the signal line driver circuit is formed using a single crystal semiconductor thin film separated from a single crystal semiconductor substrate. A base substrate;
A scanning line driving circuit and a signal line driving circuit on the base substrate;
A first interlayer film covering the scanning line driving circuit and the signal line driving circuit;
A wiring provided on the first interlayer film and electrically connected to the scanning line driving circuit and the signal line driving circuit;
A second interlayer film covering the wiring;
An image display unit provided on the second interlayer film, and electrically connected to the scanning line driving circuit and the signal line driving circuit by the wiring, and having a plurality of pixels in a matrix,
Both the scanning line driving circuit and the signal line driving circuit overlap with the image display unit,
A display device, wherein an active layer of a transistor included in the scan line driver circuit and the signal line driver circuit is formed using a single crystal semiconductor thin film separated from a single crystal semiconductor substrate. The image display unit includes a switching element,
The switching device, a display device according to claim 1 or 2 having a different semiconductor material than the active layer of the transistor included in the said scanning line driving circuit and the signal line driver circuit. The display device according to claim 3 , wherein the switching element includes an oxide semiconductor .   An electronic device comprising the display device according to any one of claims 1 to 4. 5. A plurality of display devices having the structure according to claim 1, wherein a substrate that transmits light of a wavelength of 300 nm to 700 nm inclusive is 80% or more is used as the base substrate.
And the image display unit and forehead edge portion in a display device adjacent overlapping electronic apparatus.