JP2003282273A - Display device, its manufacturing method, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device and electronic equipment improving environment resistance such as moisture resistance and oxidation resistance of a luminescent region and improving display characteristics and reliability. <P>SOLUTION: This display device is characterized in that the luminescent layer is sandwiched between a positive electrode layer and a negative electrode layer, a pixel part 110 including the luminescent layer is provided with the luminescent region 111 having an organic EL (electroluminescent) layer, and a dummy region 112 formed in the peripheral part of the luminescent region 111, and a negative layer 50 is formed of two-layer structure of a Ca negative electrode layer 50a covering the luminescent region 111 and the dummy region 112, and an Al negative electrode layer 50b covering the Ca negative electrode layer 50a. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device which is excellent in environmental resistance such as moisture resistance and oxidation resistance, has little change over time in display characteristics and the like, and is excellent in reliability, a manufacturing method thereof, and electronic equipment. is there.

[0002]

2. Description of the Related Art Conventionally, in an optical display device such as an electroluminescence (hereinafter abbreviated as EL) display device, a plurality of circuit elements, an anode, an electro-optical material such as an EL material, a cathode and the like are laminated on a substrate. Some have a different configuration. Specifically, it has a structure in which a light-emitting layer containing a light-emitting substance is sandwiched between electrode layers of an anode and a cathode, and a hole injected from the anode side and an electron injected from the cathode side have a fluorescent ability. It utilizes the phenomenon that light is recombined in the light-emitting layer that it has and emits light when it is collapsed from the excited state.

For example, in an organic EL device using an organic EL substance, Ca metal or the like is used as a cathode material which directly forms an interface with the organic EL film and plays a role of electron injection. The cathode material such as Ca metal is usually formed by a vapor deposition method, a sputtering method, or the like. For example, in a full-color display or the like, a mask having the same pattern is used because of the simplicity of the process and the device. Often used, especially when the cathode has a multi-layer structure, the cathode pattern of each layer is the same.

[0004]

By the way, in a conventional organic EL device, particularly in a full color display or the like, when the cathode pattern of each layer is the same in a cathode having a multilayer structure, the end face of the cathode is exposed to the outside air or Since it is exposed directly to the sealing area, oxygen and moisture in the atmosphere penetrate into the inside from this exposed portion, and there is a problem that the electrical characteristics deteriorate.

Further, in the conventional organic EL device, a dummy region (non-light emitting region) is formed in the peripheral portion of the light emitting region, but when Ca metal or the like is deposited as the cathode material, the same pattern as the light emitting region is formed. When the vapor deposition is performed using the mask having the above, the cathode material such as Ca metal may not be vapor deposited in the light emitting region depending on the distance between the mask and the cathode forming position on the substrate. As described above, there is a problem that the cathode material is not vapor-deposited in a part of the light emitting region due to the pattern accuracy of the mask. Further, due to the pattern accuracy of the cathode on the light emitting region, when a large amount of in-plane variation of current and voltage occurs in the peripheral portion, there is a possibility that uneven brightness may occur in the light emitting region corresponding to the peripheral portion of the cathode.

The present invention has been made in view of the above problems, and it is possible to improve the environment resistance such as the humidity resistance and the oxidation resistance of the light emitting region and to improve the display characteristics and the reliability. An object of the present invention is to provide a display device, a manufacturing method thereof, and an electronic device.

[0007]

In order to solve the above-mentioned problems, a display device of the present invention has a light emitting region in which a light emitting layer is sandwiched between an anode layer and a cathode layer, and a pixel portion including the light emitting layer is provided. And a non-light emitting region formed in the peripheral portion of the light emitting region, wherein the cathode layer covers the light emitting region and at least an inner peripheral portion of the non light emitting region on the light emitting region side. It is characterized in that it is formed so as to cover.

In this display device, the cathode layer is formed so as to cover the light emitting region and at least the inner peripheral portion of the non-light emitting region on the light emitting region side, regardless of the pattern accuracy of the mask. , The entire light emitting region is covered with the cathode layer, and there is no possibility that oxygen and moisture in the atmosphere will enter the light emitting region from the outside.
Display characteristics and reliability are improved. Further, there is no possibility of causing a problem such as a region where the cathode material is not formed due to the pattern accuracy of the mask in a part of the light emitting region,
The manufacturing yield in the manufacturing process is improved, and the price of the display device as a product can be reduced.

In the display device of the present invention, the cathode layer includes at least a first cathode layer and a second cathode layer formed on the first cathode layer, and the first cathode layer is provided. A cathode layer is formed so as to cover the light emitting region and to cover at least the inner peripheral portion of the non-light emitting region on the light emitting region side,
It is characterized in that the second cathode layer is formed so as to cover the first cathode layer.

In this display device, the cathode layer has a two-layer structure including at least a first cathode layer and a second cathode layer, so that the entire light emitting region is covered with the cathode layer having a two-layer structure. Thus, invasion of oxygen and moisture in the atmosphere into the light emitting region from the outside is effectively prevented, and the display characteristics and reliability are further improved.

In the display device of the present invention, the first cathode layer is formed so as to cover the light emitting region and the non-light emitting region, and the second cathode layer is formed so as to cover the first cathode layer. It is characterized in that it is formed.

In this display device, by covering the light emitting region and the non-light emitting region with the first cathode layer, the entire light emitting region and the non-light emitting region are covered with the cathode layer having a two-layer structure, Invasion of atmospheric oxygen and moisture from the outside into the light emitting region is more effectively prevented, and display characteristics and reliability are significantly improved.

The first cathode layer is made of Ca metal or Ca.
And a Ca-based alloy containing as a main component, the second cathode layer,
It is preferable to use an Al metal or an Al-based alloy containing Al as a main component. The light emitting layer preferably comprises a light emitting body layer containing an electro-optic material. The electro-optical material is preferably an organic EL material.

According to the method of manufacturing a display device of the present invention, a light emitting layer is sandwiched between an anode layer and a cathode layer, and a light emitting region having a pixel portion including the light emitting layer and a peripheral portion of the light emitting region are formed. And a non-light emitting region, wherein the cathode layer is formed to cover the light emitting region and at least an inner peripheral portion of the non-light emitting region on the light emitting region side. It is characterized by

In this manufacturing method, the cathode layer is formed so as to cover the light emitting region and at least the inner peripheral portion of the non-light emitting region on the light emitting region side, so that the entire light emitting region is covered by the cathode layer. Since it is possible to reliably cover the light emitting region, it is possible to easily manufacture a display device in which there is no possibility that oxygen and moisture in the atmosphere will enter the light emitting region from the outside and which has improved display characteristics and reliability. In addition, regardless of the pattern accuracy of the mask, there is no risk of problems such as a region where the cathode material is not formed due to the pattern accuracy of the mask in a part of the light emitting region, and the manufacturing yield in the manufacturing process is improved. Therefore, the manufacturing cost of the display device can be reduced.

In the method for manufacturing a display device of the present invention, the cathode layer comprises at least a first cathode layer and a second cathode layer formed on the first cathode layer, and the first cathode layer is formed. Of the cathode layer is formed so as to cover the light emitting region and at least the inner peripheral portion of the non-light emitting region on the side of the light emitting region, and the second cathode layer covers the first cathode layer. It is characterized in that it is formed.

In this manufacturing method, the second cathode layer is
By forming the cathode layer so as to cover the first cathode layer, the cathode region having a two-layer structure is surely covered with the cathode region, so that oxygen and moisture in the atmosphere from the outside can be effectively introduced into the emission region. In addition, it is possible to easily manufacture a display device that has further improved display characteristics and reliability.

The method of manufacturing a display device according to the present invention is the first method described above.
Is formed so as to cover the light emitting region and the non-light emitting region, and the second cathode layer is formed so as to cover the first cathode layer.

In this manufacturing method, by covering the entire light emitting region and the non-light emitting region with a cathode layer having a two-layer structure, invasion of atmospheric oxygen and moisture from the outside into the light emitting region can be more effectively prevented. In addition, it becomes possible to easily manufacture a display device having significantly improved display characteristics and reliability.

The electronic equipment of the present invention is characterized by including the display device of the present invention. Examples of electronic devices using the display device of the present invention in the display unit include information processing devices such as mobile phones, mobile information terminals, watches, word processors, and personal computers. Thus, by adopting the display device of the present invention in the display unit of the electronic device, the display characteristics,
It is possible to provide an electronic device with excellent reliability.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a display device, a method of manufacturing the same, and electronic equipment of the present invention will be described with reference to the drawings. It should be noted that such an embodiment represents one aspect of the present invention and does not limit the present invention, and can be arbitrarily modified within the scope of the technical idea of the present invention. In each drawing shown below, the scales are different for each layer and each member in order to make each layer and each member recognizable in the drawing.

[First Embodiment] As a first embodiment of the present invention, a diagram for explaining an organic electroluminescence (EL) display device using an electroluminescent substance which is an example of an electro-optical substance, and in particular, an organic electroluminescence (EL) material. 1 is a plan view schematically showing the configuration of the organic EL display device according to the present embodiment, FIG. 2 is a sectional view taken along the line AB of FIG. 1, and FIG. 4 is a sectional view taken along the line C-D in FIG. 1. The organic EL display device 101 shown in these figures is
As a switching element, a thin film transistor (TFT: Th
It is an organic EL display device of an active matrix system using an in film transistor.

The organic EL display device 101 has a pixel electrode 23.
(See FIG. 2) TFT (TFT2 shown in FIG. 3 as a switching means for controlling whether or not to write a data signal.
4, which is also referred to as a pixel TFT), and a TFT (also referred to as a drive circuit TFT) that is a drive unit of a switching unit included in the scanning line drive circuit 80 and the inspection circuit 90.
Are formed on the substrate 20. Further, the pixel section 110 of the organic EL display device 101 includes an actual pixel area 111, which is a light emitting area that contributes to panel display, and an actual pixel area 111.
And a dummy region 112 which is a non-light emitting region which does not contribute to the display and which is formed in the peripheral portion of.

The organic EL display device 101 is shown in FIGS.
As shown in FIG. 3, the active matrix substrate 20 and the sealing substrate (counter substrate) 30 facing each other are formed of a sealing resin 40.
It is configured such that the desiccant 45 is inserted into a region surrounded by both the substrates 20 and 30 and the sealing resin 40 while being bonded to each other via the substrate 20, and further formed between the substrates 20 and 30. the space is filled with N ₂ gas N ₂ gas-filled layer 4
6 is formed. These active matrix substrates 2
0 and the sealing substrate 30 are made of a light-transmissive insulating plate member such as glass, quartz, or plastic.

As shown in FIG. 3, on the active matrix substrate 20, an anode (pixel electrode) 23, a hole injection / transport layer 70 capable of injecting / transporting holes from the anode 23, and an electric layer. An organic EL layer (hereinafter, also referred to as a light emitting layer) 60 including an organic EL material, which is one of optical materials, is formed in this order, and an organic EL layer 60 is formed on the organic EL layer 60.
The cathode layer 50 is formed via a buffer layer 222 which is a buffer layer that facilitates injection of electrons into the L layer 60.

As shown in FIGS. 1, 2 and 4, the cathode layer 50 has a larger area than the total area of the actual pixel region 111 and the dummy region 112 and covers the actual pixel region 111 and the dummy region 112. A substantially rectangular calcium (Ca) cathode layer 50a (first cathode layer) formed as described above,
A substantially rectangular aluminum (Al) cathode layer 50b (second cathode layer) formed to cover the Ca cathode layer 50a in a larger area than the Ca cathode layer 50a;
It has a layered structure.

The Ca cathode layer 50a is made of Ca metal or Ca.
It is composed of a Ca-based alloy containing as a main component. Ca
As the base alloy, for example, 90% by weight of Ca and 1% of Mg
A Ca-Mg alloy containing 0 wt% and an alloy with Ca and other alkaline earth metals (Mg, Sr, Ba, etc.) are preferably used. The Ca cathode layer 50a is formed by a vapor deposition method using Ca metal or a Ca-based alloy as an evaporation source, a sputtering method using a target material of a Ca metal or a Ca-based alloy, or a CVD method using a Ca-containing organic gas as a reactive gas. And the like.

The Al cathode layer 50b is made of Al metal or Al.
It is composed of an Al-based alloy containing as a main component. Al
As the base alloy, for example, 97 wt% Al and 3 Cr
An Al-Cr alloy containing wt% is preferably used. The Al cathode layer 50b is formed by a vapor deposition method using Al metal or an Al-based alloy as an evaporation source, a sputtering method using a target material of Al metal or an Al-based alloy, or Al.
A film can be formed by a CVD method using the contained organic gas as a reactive gas. Although the Al cathode layer 50b is used as the second cathode layer here, the same effect can be obtained by using a metal layer other than Al, such as an Ag layer or a Mg-Ag alloy layer.

Here, as shown in FIG. 1, a pixel TFT
24 (see FIG. 3) for scanning line drive circuit 80
Are provided on the active matrix substrate 20. On the other hand, the data line driving circuit 100 includes the data driver I
It is provided externally as C. Of course, the data line drive circuit 100 can be provided on the same active matrix substrate 20. The inspection circuit 90 is a circuit for inspecting the operation status of the organic EL display device 101, and includes, for example, inspection information output means for outputting the inspection result to the outside.

The scanning line drive circuit 80 and the data line drive circuit 100 are configured as a scanning control means and a data control means for controlling the output of a signal conducted to the scanning line and the data line. TF for pixels
It is connected to T24 (see FIG. 3). That is, the pixel TFT 24 (see FIG. 3) operates based on the operation command signals from the scanning line drive circuit 80 and the data line drive circuit 100, and the pixel TFT 24 controls the energization of the pixel electrode 23.

The drive voltages of the scanning line drive circuit 80 and the inspection circuit 90 are applied from a predetermined power source section through the drive voltage conducting section 310 (see FIG. 2) and the drive voltage conducting section 340 (see FIG. 4). . The drive control signal and the drive voltage to the scanning line drive circuit 80 and the inspection circuit 90 are supplied from a predetermined main driver or the like which controls the operation of the organic EL display device 101 to the drive control signal conducting section 320 (see FIG. 2).
And is transmitted and applied via the drive voltage conducting unit 350 (see FIG. 4). The drive control signal in this case is a command signal from the main driver or the like related to control when the scanning line drive circuit 80 and the inspection circuit 90 output signals.

Here, in the display area, the actual pixel portion 11
The configuration in the vicinity of the pixel TFT 24 provided corresponding to No. 1 will be described with reference to FIG. As shown in FIG.
On the surface of the active matrix substrate 20, a base protective layer 281 composed mainly of SiO ₂ is used as a base, and a silicon layer 241 is formed thereover. The surface of the silicon layer 241 is covered with a gate insulating layer 282 mainly composed of SiO ₂ and / or SiN.

A region of the silicon layer 241 that overlaps with the gate electrode 242 with the gate insulating layer 282 sandwiched therebetween serves as a channel region 241a. The gate electrode 242 is a part of the scanning line. On the other hand, the surface of the gate insulating layer 282 which covers the silicon layer 241 and on which the gate electrode 242 is formed is covered with the first interlayer insulating layer 283 whose main component is SiO ₂ . In addition, in the present embodiment, the “main component” component refers to a component having the highest content rate among the constituent components.

In the silicon layer 241, a low concentration source region 241b is formed on the source side of the channel region 241a.
While the high-concentration source region 241S is provided, the low-concentration drain region 241c and the high-concentration drain region 241D are provided on the drain side of the channel region 241a to form a so-called LDD (Light Doped Drain) structure. Of these, the high concentration source region 241S is
It is connected to the source electrode 243 through a contact hole 243a which is opened over the gate insulating layer 282 and the first interlayer insulating layer 283. The source electrode 243 is
It is configured as a part of the data line described above (extending in the direction perpendicular to the paper surface of FIG. 3). On the other hand, the high-concentration drain region 241D includes the gate insulating layer 282 and the first interlayer insulating layer 2
The drain electrode 244, which is formed of the same layer as the source electrode 243, is connected to the drain electrode 244 via a contact hole 244a which is opened over the area 83.

Source electrode 243 and drain electrode 244
The upper layer of the first interlayer insulating layer 283 on which is formed is, for example, a second interlayer insulating layer 284 mainly composed of an acrylic resin component.
Is covered by. The second interlayer insulating layer 284 is
Materials other than acrylic insulating film, such as SiN and Si
O ₂ or the like can also be used. Then, the pixel electrode 23 made of ITO is formed on the surface of the second interlayer insulating layer 284, and the drain electrode 24 is formed through the contact hole 23 a provided in the second interlayer insulating layer 284.
4 is connected. That is, the pixel electrode 23 is connected to the high concentration drain region 241D of the silicon layer 241 via the drain electrode 244.

The scanning line drive circuit 80 and the inspection circuit 9
TFT included in 0 (TFT for drive circuit), that is,
For example, of these drive circuits, the N-channel type or P-channel type TFT which constitutes the inverter included in the shift register has the same structure as the TFT 24 except that it is not connected to the pixel electrode 23. .

The pixel electrode 23 is formed as shown in FIGS.
Are separated from each other in the horizontal direction of the paper and in the direction perpendicular to the paper.
It is formed so as to correspond to the display area. Also, the pixel
The surface of the second interlayer insulating layer 284 on which the pole 23 is formed is
Elementary electrode 23 and, for example, SiO ₂Lyophilic materials such as
From the lyophilic control layer 25 and acrylic or polyimide
Is covered with the organic bank layer 221. That
The pixel electrode 23 has an opening provided on the lyophilic control layer 25.
Mouth 25a and opening provided in the organic bank 221
Inside the opening of 221a, the hole injection / transport layer 70 and the organic
The EL layer 60 is laminated in this order from the pixel electrode 23 side.
There is. In addition, the lyophilic control layer 25 in the present embodiment
“Lyophile” means at least the organic bank layer 221.
Higher lyophilicity than materials such as acrylic and polyimide
It means no.

Hole injection / transport layer 70 and organic EL layer 60
And the upper layer of the buffer layer 222 and the calcium layer 50a.
And a cathode layer 50 having a two-layer structure of an aluminum layer 50b.
Covered by and. The organic EL display device 101 is
Basically, the above configuration is provided, but in FIG. 2, the life is extended by using the desiccant 45 with the sealing substrate 30.

The organic EL display device 101 of this embodiment is
As shown in FIG. 5, each organic EL is used for color display.
The layer 60 is formed so that its emission wavelength band corresponds to each of the three primary colors of light. For example, a red display region R including a red organic EL layer 60R whose emission wavelength band corresponds to red, a green display region G including a green organic EL layer 60G corresponding to green, and a blue organic EL corresponding to blue. Layer 6
A blue display area B including 0B is provided for each dot, and these display areas R, G, and B form one pixel. In addition, BM (black matrix) formed by depositing metallic chromium on the boundary of each color display region by sputtering or the like.
Are formed between the organic bank layer 221 and the lyophilic control layer 25.

In the respective color light emitting regions R, G and B, as shown in FIG.
, Each buffer layer 222R, 222G, 22
The main constituent components of 2B are CaF ₂ , BaF ₂ , and L, respectively.
iF, and the constituent main component is different for each color light emitting region. Therefore, the amount of electrons injected per unit time is different for each color light emitting region, and the luminance and the luminous efficiency are balanced for each color region having a different emission wavelength band.

For example, in the blue light emitting region B, which is a light emitting region of a relatively short wavelength, a constituent main component capable of relatively increasing the amount of electron injection, such as LiF, is used as the blue buffer layer 222B, In the green emission region G, which is a long-wavelength emission region, a constituent main component capable of relatively reducing the amount of electron injection, for example, BaF ₂ is used as the green buffer layer 222G, and a relatively long wavelength emission region is used. In the red light emitting region R, which is the light emitting region of, the constituent main component capable of further reducing the amount of electron injection,
For example, CaF ₂ is used as the red buffer layer 222R to balance the electron injection rate (electron injection amount per unit time) for each color light emitting region. Therefore, it is possible to suppress excessive electron injection for each color light emitting region, and it is possible to suppress variation in the life of the organic EL layer 60 in each color light emitting region R, G, B, and thus the EL display device 1
It is possible to improve the life of No. 01.

Further, in the present embodiment, as shown in FIG. 5, the buffer layer 222 is formed over the entire surface of the pixel, that is, over each dot. However, for example, as shown in FIG. 6, each of the organic bank layers 221 is formed. Recessed partition area 223 formed between
It is also possible to form it only, that is, by stacking it on the pixel electrode 23 with a predetermined film thickness. In this case, each buffer layer 2
22R, 222G, 222B can be easily deposited.

In the buffer layer 222, the luminance and luminous efficiency are balanced for each color by using different constituent main components for the respective color luminous areas R, G, B. For example, for each color luminous area In all of the above, by using NaF, BaF ₂ , SrF ₂ , or MgF ₂ as the buffer layer having the same component and the same film thickness, it is possible to balance the luminance and the light emission efficiency for each color.
In this case, NaF and Ba, which have a relatively low electron injection rate,
Since any one of F ₂ , SrF ₂ , and MgF ₂ is used for the buffer layer of each color, the life of the organic EL layer 60 is improved particularly in the red light emitting region R and the green light emitting region G.

Next, an example of the manufacturing process of the organic EL display device 101 according to this embodiment will be described with reference to FIGS.
This will be described with reference to 1. The sectional views shown in FIGS. 7 to 11 correspond to the sectional view taken along the line AB in FIG. 1 and are shown in the order of respective manufacturing steps.

First, as shown in FIG. 7A, a base protective layer 281 made of a silicon oxide film or the like is formed on the surface of an active matrix substrate 20 made of an insulating quartz substrate or glass substrate. Next, an amorphous silicon layer 501 is formed on the base protective layer 281 by using the ICVD method, the plasma CVD method, or the like, and then a crystal grain is grown by a laser annealing method or a rapid heating method to form a polysilicon layer.

Then, as shown in FIG. 7B, the polysilicon layer is patterned by photolithography to form island-shaped silicon layers 241, 251 and 261. Of these, the silicon layer 241 is formed in the display area and is connected to the pixel electrode 23.
FT) 24, the silicon layer 251,
Reference numerals 261 respectively constitute P-channel type TFTs and N-channel type TFTs (driving circuit TFTs) included in the scanning line driving circuit 80.

Next, a gate insulating layer 282 made of a silicon oxide film having a thickness of about 30 nm to 200 nm is formed on the entire surfaces of the silicon layers 241, 251 and 261 and the base protection layer 281 by plasma CVD method, thermal oxidation method or the like. Form. Here, when the gate insulating layer 282 is formed by using the thermal oxidation method, the silicon layers 241, 251 and 261 are formed.
Can also be crystallized to form these silicon layers as polysilicon layers.

Also, the silicon layers 241, 251 and 26
In the case of performing channel doping on No. 1, for example, boron ions are implanted with a dose amount of about 1 × 10 ¹² cm ⁻² at this timing. As a result, the silicon layers 241, 251 and 261 become low-concentration P-type silicon layers having an impurity concentration (calculated by impurities after activation annealing) of about 1 × 10 ¹⁷ cm ⁻³ .

Next, an ion implantation selection mask is formed on a part of the channel layers of the P-channel TFT and the N-channel TFT, and phosphorus ions are ion-implanted in this state at a dose amount of about 1 × 10 ¹⁵ cm ^-2. . As a result, self-aligned high-concentration impurities are introduced into the patterning mask, and as shown in FIG. 7C, the high-concentration source regions 241S and 261S and the high-concentration drain regions are formed in the silicon layers 241 and 261. 241D and 261D are formed.

Next, as shown in FIG. 7C, on the entire surface of the gate insulating layer 282, for forming a gate electrode made of a doped silicon or silicide film, or a metal film such as an aluminum film, a chromium film or a tantalum film. The conductive layer 502 is formed. The conductive layer 502 has a thickness of about 500 nm. Then, as shown in FIG. 7D, a gate electrode 252 for forming a P-channel type driving circuit TFT, a gate electrode 242 for forming a pixel TFT, and an N-channel type driving circuit TFT are patterned by a patterning method. The gate electrode 262 to be formed is formed. Further, the drive control signal conducting portion 320 (350) and the first layer 121 of the cathode power supply wiring are also formed at the same time. In this case, the drive control signal conducting section 3
20 (350) is arranged in the dummy area 112.

Subsequently, as shown in FIG. 7D, using the gate electrodes 242, 252 and 262 as a mask, phosphorus ions are applied to the silicon layers 241, 251 and 261 at a dose of about 4 × 10 ¹³ cm ^-2 . Ion implantation in a quantity. As a result, low-concentration impurities are introduced into the gate electrodes 242, 252, and 262 in a self-aligned manner.
As shown in (c) and (d), low concentration source regions 241b and 261b and low concentration drain regions 241c and 261c are formed in the silicon layers 241 and 261. In addition, in the silicon layer 251, the low concentration impurity region 2
51S and 251D are formed.

Next, as shown in FIG. 8E, an ion implantation selection mask 503 is formed to cover a portion other than the P-channel drive circuit TFT 252. Using this ion implantation selection mask 503, boron ions are ion-implanted into the silicon layer 251 at a dose of about 1.5 × 10 ¹⁵ cm ⁻² . As a result, a TFT for a P-channel drive circuit
Since the gate electrode 252 forming the gate electrode 252 also functions as a mask, the high-concentration impurity is self-alignedly doped into the silicon layer 252. Therefore, the low concentration impurity region 251
S and 251D are counter-doped and serve as a source region and a drain region of a P-type channel TFT for a drive circuit.

Next, as shown in FIG. 8F, a first interlayer insulating layer 283 is formed over the entire surface of the active matrix substrate 20, and the first interlayer insulating layer 283 is formed by using a photolithography method. By patterning, the contact hole C is formed at a position corresponding to the source electrode and the drain electrode of each TFT.

Next, as shown in FIG. 8G, a conductive layer 504 made of a metal such as aluminum, chromium, or tantalum is formed so as to cover the first interlayer insulating layer 283. The thickness of this conductive layer 504 is approximately 200 nm to 800 nm.
It is a degree. After that, in the conductive layer 504, the regions 24 where the source and drain electrodes of each TFT are to be formed
0a, the region 310a in which the drive voltage conducting portion 310 (340) is to be formed, and the region 122a in which the second layer of the cathode power supply wiring is to be formed are patterned mask 50.
5 is formed, and the conductive layer 504 is patterned to form the source electrodes 243, 253, shown in FIG.
263 and drain electrodes 244, 254 and 264 are formed.

Next, as shown in FIG. 9I, a second interlayer insulating layer 284 covering the first interlayer insulating layer 283 on which they are formed is formed of a polymer material such as acrylic resin. The second interlayer insulating layer 284 has a thickness of about 1 to
It is desirable to be formed to a thickness of about 2 μm. In addition,
It is also possible to form the second interlayer insulating film from SiN and SiO ₂ , and the film thickness of SiN is 200 nm,
The film thickness of ₂ is preferably 800 nm.

Next, as shown in FIG. 9J, the drain electrode 2 of the pixel TFT in the second interlayer insulating layer 284.
The portion corresponding to 44 is removed by etching to form the contact hole 23a. After that, a transparent conductive film made of a transparent electrode material such as ITO is formed so as to cover the entire surface of the active matrix substrate 20. Then, by patterning this transparent conductive film, as shown in FIG. 10K, the pixel electrode 23 that is electrically connected to the drain electrode 244 through the contact hole 23 a of the second interlayer insulating layer 284 is formed, and at the same time, the dummy electrode is formed. A dummy pattern 26 in the area is also formed. In FIG.
3. The dummy pattern 26 is collectively referred to as the pixel electrode 23.

The dummy pattern 26 is the second interlayer insulating layer 2
It is configured not to be connected to the metal wiring in the lower layer via 84. That is, the dummy pattern 26 is arranged in an island shape and has a shape substantially the same as the shape of the pixel electrode 23 formed in the display region. Of course, the shape may be different from the shape of the pixel electrode 23 formed in the display area. In this case, the dummy pattern 26 includes at least the dummy pattern 26 located above the drive voltage conducting portion 310 (340).

Next, as shown in FIG. 10L, a lyophilic control layer 25 as an insulating layer is formed on the pixel electrode 23, the dummy pattern 26 and the second interlayer insulating film. Note that the insulating layer (lyophilic control layer) 25 is formed in such a manner that a part of the pixel electrode 23 is open, and the opening 25a (see FIG. 3) is formed.
(See also), holes can be moved from the pixel electrode 23. On the contrary, in the dummy pattern 26 having no opening 25a, the insulating layer (lyophilic control layer) 25 serves as a hole movement blocking layer and does not cause hole movement.

Next, as shown in FIG. 10L, BM (black matrix) is formed in the concave portion formed between the two different pixel electrodes 23 in the lyophilic control layer 25. Specifically, metal chrome is used to form a film on the concave portion of the lyophilic control layer 25 by a sputtering method.

Next, as shown in FIG. 10 (m), an organic bank layer 221 is formed so as to cover a predetermined position of the lyophilic control layer 25, specifically, the BM. As a specific method for forming the organic bank layer, for example, a resist such as an acrylic resin or a polyimide resin dissolved in a solvent is applied by various coating methods such as a spin coating method and a dip coating method to form an organic layer. . The constituent material of the organic layer is
Any material may be used as long as it does not dissolve in the ink solvent described below and is easily patterned by etching or the like.

Next, the organic layer is simultaneously etched by a photolithography technique or the like to form a bank opening 221a of an organic material, and an organic bank layer (partition wall) 221 having a wall surface in the opening 221a is formed. In this case, the organic bank layer 221 is assumed to include at least one located above the drive control signal conducting portion 320 (350).

Next, on the surface of the organic bank layer 221, a lyophilic region and a lyophobic region are formed. In this embodiment, each region is formed by a plasma treatment process. Specifically, the plasma treatment step includes a preheating step, an upper surface of the organic bank layer 221, a wall surface of the opening 221a, an electrode surface of the pixel electrode 23 (surface of the pixel electrode) 23c, and a lyophilic control layer 25. An ink-repellent process for making the upper surface lyophilic, an ink-repellent process for making the upper surface of the organic bank layer and the wall surface of the opening lyophobic, and a cooling process are provided.

That is, the base material (the substrate 2 including the bank, etc.)
0) is heated to a predetermined temperature, for example, about 70 to 80 ° C., and then plasma treatment (O ₂ plasma treatment) using oxygen as a reaction gas is performed in the atmosphere as an ink-philic step. Next, as an ink repellent process, plasma treatment (CF ₄ plasma treatment) using tetrafluoromethane as a reaction gas is performed in the air atmosphere, and then the substrate heated for plasma treatment is cooled to room temperature. Thus, the lyophilic property and the lyophobic property are imparted to a predetermined place.

In the CF ₄ plasma treatment, the electrode surface 23c of the pixel electrode 23 and the lyophilic control layer 25 are formed.
However, ITO (Indium Tin Oxide) which is the material of the pixel electrode 23 and SiO ₂ and TiO ₂ which are the constituent materials of the insulating layer (lyophilic control layer) 25 have an affinity for fluorine. Since it is scarce, the hydroxyl group added in the ink-philic step is not replaced with a fluorine group, and the lyophilic property is maintained.

Next, a hole injecting / transporting layer forming step is performed to form the hole injecting / transporting layer 70 (see also FIG. 3) shown in FIG. 11 (n). In the hole injecting / transporting layer forming step, after the composition ink containing the hole injecting / transporting layer material is ejected onto the electrode surface 23c by an inkjet method, a drying process and a heat treatment are performed to inject the hole into the electrode 23. / Form the transport layer 70. After the step of forming the hole injecting / transporting layer, it is preferable to carry out in an inert gas atmosphere such as a nitrogen atmosphere or an argon atmosphere in order to prevent the hole injecting / transporting layer 70 and the organic EL layer 60 from being oxidized.

For example, an inkjet head (not shown)
Filled with a composition ink containing a hole injection / transport layer material,
The ejection nozzle of the inkjet head is used as the lyophilic control layer 25.
Electrode surface 23 located in the opening 25a formed in the
c to face the inkjet head and the substrate (substrate 2
0) is relatively moved, and a droplet whose liquid amount per droplet is controlled is ejected from the ejection nozzle to the electrode surface 23c.
Next, the hole injection / transport layer 70 is formed by drying the discharged droplets to evaporate the polar solvent contained in the composition ink.

As the composition ink, for example, a polythiophene derivative such as polyethylenedioxythiophene,
A mixture of polystyrene sulfonic acid or the like dissolved in a polar solvent such as isopropyl alcohol can be used. Here, the ejected droplets spread on the electrode surface 23c that has been subjected to the ink-philic treatment, and the insulating layer (lyophilic control layer) 2
5 is filled in the opening 25a. On the other hand, droplets are repelled and do not adhere to the upper surface of the organic bank layer 221 that has been subjected to the ink repellent treatment. Therefore, even if the droplets are ejected from the predetermined ejection position onto the upper surface of the organic bank layer 221, the upper surface is not wetted by the droplets and the repelled droplets are opened in the lyophilic control layer 25. Rolls into the portion 25a. As the material of the hole injecting / transporting layer 70, for example, a mixture of polythiophene derivative such as polyethylenedioxythiophene and polystyrene sulfonic acid can be used.

Next, as shown in FIG. 11 (n), a light emitting layer forming step is performed to form an organic EL layer (light emitting layer) 60 (see also FIG. 3). In the light emitting layer forming step, the composition ink containing the light emitting layer material is ejected onto the hole injecting / transporting layer 70 by the same inkjet method as described above, and then dried and heat-treated to form the organic bank layer 221. The organic EL layer 60 is formed in the opening 221a.

In this light emitting layer forming step, in order to prevent the redissolving of the hole injecting / transporting layer 70, the hole injecting / transporting layer 70 is used as a solvent for the composition ink used in forming the light emitting layer.
A non-polar solvent insoluble in is used. In this light emitting layer forming step, for example, an inkjet head (not shown)
A hole injecting / transporting layer in which the composition ink containing the material of the blue (B) light emitting layer is filled, and the ejection nozzle of the inkjet head is located in the opening 25a of the insulating layer (lyophilic control layer) 25. The droplets are discharged from the discharge nozzle as droplets whose liquid amount is controlled while facing the ink jet head and the base material relative to each other, and the droplets are discharged onto the hole injection / transport layer 70. To do.

As the light emitting material forming the organic EL layer 60, polyfluorene derivatives, polyphenylene derivatives,
Polyvinylcarbazole, polythiophene derivatives, perylene-based dyes, coumarin-based dyes, rhodamine-based dyes, or polymeric materials thereof, such as rubrene, perylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, coumarin 6, quinacridone Etc. can be used by doping. On the other hand, the non-polar solvent is preferably one that is insoluble in the hole injecting / transporting layer 70, such as cyclohexylbenzene, dihydrobenzofuran, trimethylbenzene,
Tetramethylbenzene or the like can be used.

The discharged droplets are the hole injection / transport layer 70.
It spreads upward and is filled in the opening 25a of the lyophilic control layer 25. On the other hand, on the upper surface of the organic bank layer 221, which has been subjected to the ink repellent treatment, the droplets are repelled and not attached. As a result, the liquid droplets deviate from the predetermined ejection position and the organic bank layer 2
21 Even if the liquid is ejected onto the upper surface, the upper surface is not wetted by the liquid droplet, and the liquid droplet does not wet the opening 25 of the lyophilic control layer 25.
It rolls into the inside of a and is further discharged and filled in the opening 221a of the organic bank layer 221. Next, the discharged liquid droplets are dried to evaporate the non-polar solvent contained in the composition ink, whereby the organic EL layer 60 is formed. It should be noted that droplets are dropped on the organic EL layers 60R, 60G, and 60B of the respective colors so as to correspond to the light emitting regions R, G, and B (see FIG. 5) of the respective colors.

Here, the hole injection / transport layer 70, the organic EL
Each of the layers 60 is formed by an inkjet process. At this time, the inkjet head controls the inclination direction by the pitch between the light emitting dots. That is, the pitch of the nozzles formed in the inkjet head,
Since the pitch does not always match the pitch of the light emitting dots, the head is tilted to adjust the pitch of the light emitting dots.

Next, as shown in FIG. 11N, the buffer layer 222 is formed on the organic EL layer 60. In the present embodiment, the buffer layers having different constituents for each color of the organic EL layer 60 described above are formed by vapor deposition. Specifically, a red buffer layer 222R containing CaF ₂ as a main constituent is provided on the red organic EL layer 60R, and a green buffer layer containing BaF ₂ as a main constituent is provided on the green organic EL layer 60G. 222G to the blue organic EL layer 60B
A blue buffer layer 2 containing LiF as a main constituent
22B is formed. In addition, on the entire surface of the organic bank layer 221, a buffer layer 222 for each color corresponding to the organic EL layer for each color is formed.
May be formed.

Next, as shown in FIG. 11 (o), a cathode layer forming step is performed to form the cathode layer 50. In this cathode layer forming step, the Ca cathode layer 5 serving as the cathode layer 50 is formed on the entire surfaces of the buffer layer 222 and the organic bank layer 221.
0a and the Al cathode layer 50b are sequentially laminated.

First, the Ca cathode layer 50a is formed. More specifically, a vapor deposition method using Ca metal or a Ca-based alloy as an evaporation source, a sputtering method using a target material of a Ca metal or a Ca-based alloy, a CVD method using a Ca-containing organic gas as a reactive gas, or the like. Thus, the Ca cathode layer 50a is formed. Since the Ca cathode layer 50a needs to be formed so as to completely cover the actual pixel region 111 and the dummy region 112, the occupied area thereof is larger than the total area of the actual pixel region 111 and the dummy region 112. .

Next, the Al cathode layer 50b is formed. More specifically, a vapor deposition method using Al metal or an Al-based alloy as an evaporation source, a sputtering method using a target material of Al metal or an Al-based alloy, a CVD method using an Al-containing organic gas as a reactive gas, and the like. Thus, the Al cathode layer 50b is formed. Since the Al cathode layer 50b needs to be formed so as to completely cover the Ca cathode layer 50a covering the actual pixel region 111 and the dummy region 112, the occupied area is larger than that of the Ca cathode layer 50a. .

As described above, the Ca cathode layer 50a formed so as to cover the actual pixel region 111 and the dummy region 112.
And Al formed so as to cover the Ca cathode layer 50a.
The cathode layer 50 having a two-layer structure including the cathode layer 50b can be formed. If a cathode material such as Ag or Mg-Ag alloy is used instead of the cathode material made of Al metal or Al-based alloy, the Ag cathode layer, the Mg-Ag cathode layer, etc. can be formed.

Finally, as shown in FIG. 11 (o), a sealing step is performed to form the sealing substrate 30. In this sealing step, the sealing substrate 30 and the active matrix substrate 20 are sealed with the adhesive 40 while the desiccant 45 is inserted inside the sealing substrate 30. The sealing process is preferably performed in an atmosphere of an inert gas such as nitrogen, argon or helium. When performed in the atmosphere, when a defect such as a pinhole occurs in the reflective layer, water, oxygen or the like may enter the cathode layer 50 from this defect portion and the cathode layer 50 may be oxidized. . The organic EL display device 101 according to the present embodiment can be obtained by the manufacturing process as described above.

According to the organic EL display device 101 of the present embodiment, the entire light emitting region is covered with the cathode layer regardless of the pattern accuracy of the mask, so that the hole injection / transport layer 70 and the organic EL layer 60 are externally applied. Oxygen and water in the atmosphere are not likely to enter, and display characteristics and reliability can be improved. Further, since there is no possibility of causing a problem such as a region where the cathode material is not formed due to the pattern accuracy of the mask in a part of the light emitting region, it is possible to improve the manufacturing yield in the manufacturing process, The manufacturing cost can be reduced.

Further, since the cathode layer 50 has a two-layer structure consisting of the Ca cathode layer 50a and the Al cathode layer 50b, the hole injecting / transporting layer 70 and the organic EL layer 60 are exposed to the atmosphere from the outside. Invasion of oxygen and moisture can be effectively prevented, and display characteristics and reliability can be further improved.

According to the method of manufacturing the organic EL display device 101 of this embodiment, the hole injection / transport layer 70 and the organic EL layer 6 are formed.
With respect to 0, there is no possibility of invasion of oxygen and moisture in the atmosphere from the outside, and a display device having improved display characteristics and reliability can be easily manufactured. Further, regardless of the pattern accuracy of the mask, there is no possibility of causing a problem such as a region where the cathode material is not formed due to the pattern accuracy of the mask in a part of the light emitting region, thereby improving the manufacturing yield in the manufacturing process. Therefore, the manufacturing cost of the display device can be reduced.

[Second Embodiment] FIG. 12 is a plan view schematically showing the structure of an organic EL display device according to this embodiment.
13 is a sectional view taken along the line EF of FIG. 12, and FIG. 14 is FIG.
It is sectional drawing which follows the GH line of FIG. The organic EL display device 501 shown in these figures is an active matrix organic EL display device using a thin film transistor (TFT) as a switching element.

Organic EL display device 501 according to the present embodiment
However, the difference from the organic EL display device 101 of the first embodiment described above is the shape of the cathode layer, and the other points are exactly the same. The cathode layer 502 of the present embodiment includes a substantially rectangular Ca cathode layer 502a (first cathode layer) and this Ca layer.
Al having a substantially rectangular shape formed so as to cover the cathode layer 502a.
It has a two-layer structure including a cathode layer 502b (second cathode layer).

The Ca cathode layer 502a is formed on the actual pixel region 111.
The real pixel area 111 of the dummy area 112
Is formed so as to cover the inner peripheral portion on the side, and the area thereof is larger than the area of the actual pixel region 111 and the actual pixel region 111.
The area is smaller than the total area of the dummy region 112. The Al cathode layer 502b is formed so as to cover the Ca cathode layer 502a and a part of the dummy region 112 located outside the Ca cathode layer 502a, and the area thereof is
The area is larger than the area of the Ca cathode layer 502a and smaller than the total area of the actual pixel area 111 and the dummy area 112.

Also in the organic EL display device 101 of this embodiment, the organic EL display device 10 of the first embodiment described above is also used.
The same effect as that of No. 1 can be obtained. Moreover, since the Al cathode layer 502b is formed so as to cover the Ca cathode layer 502a, oxygen and moisture in the atmosphere from the outside can be more effectively introduced into the hole injection / transport layer 70 and the organic EL layer 60. It is possible to prevent this, and display characteristics and reliability can be significantly improved.

[Third Embodiment] Hereinafter, the first or second embodiment
Specific examples of electronic devices including the organic EL display device of the embodiment will be described with reference to FIG. FIG. 15A shows
It is a perspective view showing an example of a mobile phone. In FIG. 15A, reference numeral 1000 indicates a mobile phone body, and reference numeral 10
Reference numeral 01 denotes a display unit using the above organic EL display device. FIG. 15B is a perspective view showing an example of a wrist watch type electronic device. In FIG. 15B, reference numeral 1100
Indicates a watch body, and reference numeral 1101 indicates a display unit using the organic EL display device. FIG. 15C is a perspective view showing an example of a portable information processing device such as a word processor or a personal computer. In FIG. 15C, reference numeral 120
Reference numeral 120 is an information processing apparatus, reference numeral 1201 is an input unit such as a keyboard, reference numeral 1202 is a display unit using the organic EL display device, and reference numeral 1203 is an information processing apparatus main body.

Each of the electronic devices shown in FIGS. 15 (a) to 15 (c) is the organic EL device of the first or second embodiment.
A display unit using a display device is provided.
Alternatively, since the organic EL display device has the characteristics of the second embodiment, the electronic device has improved display characteristics and reliability and reduced manufacturing cost. In order to manufacture these electronic devices, the organic EL display device 10 according to the first embodiment is used.
The organic EL display device 501 of the first or second embodiment is
It is manufactured by being incorporated in the display section of various electronic devices such as a mobile phone, a portable information processing device, and a wristwatch type electronic device.

[0088]

As described above in detail, according to the display device of the present invention, the light emitting layer is sandwiched between the anode layer and the cathode layer, and the light emitting region having the pixel portion including the light emitting layer is provided. A non-light emitting region formed in the peripheral portion of the light emitting region, wherein the cathode layer is formed to cover the light emitting region and at least an inner peripheral portion of the non light emitting region on the light emitting region side. Therefore, invasion of oxygen and moisture in the atmosphere into the light emitting region can be prevented, and display characteristics and reliability can be improved. Further, there is no possibility of causing a problem such as a region where the cathode material is not formed due to the pattern accuracy of the mask in a part of the light emitting region, and it is possible to improve the manufacturing yield in the manufacturing process. The price can be reduced.

Further, if the cathode layer has a two-layer structure of at least a first cathode layer and a second cathode layer, the entire emission region is covered with the cathode layer having a two-layer structure, so that this emission region is reached. It is possible to effectively prevent the invasion of oxygen and moisture in the atmosphere, and further improve the display characteristics and reliability.

According to the method of manufacturing a display device of the present invention, the cathode layer is formed so as to cover the light emitting region and at least the inner peripheral portion of the non-light emitting region on the light emitting region side. It is possible to easily fabricate a display device in which there is no possibility that oxygen or moisture in the atmosphere will enter the region from the outside and which has improved display characteristics and reliability. Also,
Regardless of the pattern accuracy of the mask, there is no risk of problems such as a region where the cathode material is not formed due to the pattern accuracy of the mask in a part of the light emitting region, improving the manufacturing yield in the manufacturing process, and displaying The manufacturing cost of the device can be reduced.

[Brief description of drawings]

FIG. 1 is a plan view showing a configuration of an organic EL display device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line AB of FIG.

3 is an enlarged cross-sectional view of a main part of FIG.

FIG. 4 is a cross-sectional view taken along the line CD of FIG.

5 is an explanatory diagram showing a structure of a buffer layer of the organic EL display device of FIG.

FIG. 6 is an explanatory diagram showing a modified example of the configuration of the buffer layer.

FIG. 7 is a process chart showing the manufacturing method of the organic EL display device according to the first embodiment of the present invention.

FIG. 8 is a process chart showing the manufacturing method of the organic EL display device according to the first embodiment of the present invention.

FIG. 9 is a process chart showing the manufacturing method of the organic EL display device according to the first embodiment of the present invention.

FIG. 10 is a process chart showing the manufacturing method of the organic EL display device according to the first embodiment of the present invention.

FIG. 11 is a process chart showing the manufacturing method of the organic EL display device according to the first embodiment of the present invention.

FIG. 12 is a plan view showing a configuration of an organic EL display device according to a second embodiment of the present invention.

13 is a cross-sectional view taken along the line EF of FIG.

14 is a cross-sectional view taken along the line GH in FIG.

FIG. 15 is a perspective view showing an electronic device according to a third embodiment of the present invention.

[Explanation of symbols]

20 Active matrix substrate 23 Anode layer 50 cathode layer 50a Ca cathode layer (first cathode layer) 50b Al cathode layer (second cathode layer) 60 organic EL layer (light emitting layer) 101 Organic EL display device 501 organic EL display device 502 cathode layer 502a Ca cathode layer (first cathode layer) 502b Al cathode layer (second cathode layer)

Claims (10)

[Claims] 1. A light emitting layer is sandwiched between an anode layer and a cathode layer, the light emitting region having a pixel portion including the light emitting layer, and a non-light emitting region formed in a peripheral portion of the light emitting region. In the display device described above, the cathode layer is formed so as to cover the light emitting region and at least an inner peripheral portion of the non-light emitting region on the light emitting region side. 2. The cathode layer includes at least a first cathode layer and a second cathode layer formed on the first cathode layer, and the first cathode layer includes the light emitting region. The second cathode layer is formed to cover at least the inner peripheral portion of the non-light emitting area on the light emitting area side, and the second cathode layer is formed to cover the first cathode layer. The display device according to claim 1. 3. The first cathode layer is formed so as to cover the light emitting region and the non-light emitting region, and the second cathode layer is formed so as to cover the first cathode layer. The display device according to claim 2, wherein: 4. The first cathode layer comprises Ca metal or C
4. The display device according to claim 2, wherein the display device is made of a Ca-based alloy containing a as a main component, and the second cathode layer is made of Al metal or an Al-based alloy containing Al as a main component. 5. The light emitting layer comprises a light emitting body layer containing an electro-optic material.
The display device according to claim 1. 6. The display device according to claim 5, wherein the electro-optical material is an organic EL material. 7. A light emitting layer is sandwiched between an anode layer and a cathode layer, the light emitting region having a pixel portion including the light emitting layer, and a non-light emitting region formed in the peripheral portion of the light emitting region. A method of manufacturing a display device, wherein the cathode layer is formed so as to cover the light emitting region and to cover at least the inner peripheral portion of the non-light emitting region on the light emitting region side. Production method. 8. The cathode layer is composed of at least a first cathode layer and a second cathode layer formed on the first cathode layer, and the first cathode layer is the light emitting region. And forming the second cathode layer so as to cover at least the inner peripheral portion of the non-light emitting region on the light emitting region side, and the second cathode layer so as to cover the first cathode layer. A method of manufacturing a display device according to claim 7. 9. The first cathode layer is formed so as to cover the light emitting region and the non-light emitting region, and the second cathode layer is formed so as to cover the first cathode layer. The method for manufacturing a display device according to claim 8, wherein the display device is manufactured. 10. An electronic apparatus comprising the display device according to claim 1. Description: