JP6040443B2 - Display panel manufacturing method and display panel - Google Patents

Description

  The present invention relates to a method for manufacturing a display panel, and more particularly to a manufacturing technique for a sealing layer.

Some light-emitting elements used for display panels have a structure in which a light-emitting functional layer including a light-emitting layer and a conductive layer is interposed between an anode and a cathode. Among these light emitting elements, there is one using a light emitting element (organic EL element) using an organic material.
In this organic EL element, the light emitting functional layer, the anode, and the cathode are made of a material that can react with a gas such as water vapor or oxygen (hereinafter, also simply referred to as “gas such as water vapor”). Therefore, the light emitting functional layer reacts with a gas such as water vapor, resulting in a decrease in light emission characteristics and a decrease in life. In addition, the anode and the cathode react with a gas such as water vapor, resulting in a change in electrical characteristics (for example, electrical conductivity). When the electrical characteristics of the cathode change greatly, no charge is supplied to the light emitting functional layer, and a non-light emitting portion (dark spot) is generated in a part of the display panel, leading to a deterioration in display quality of the display panel.

On the other hand, in this type of display panel, a sealing layer is formed so as to cover the upper surface of the cathode in order to prevent gas such as water vapor from adsorbing on the cathode surface or entering the light emitting functional layer. ing.
On the other hand, in the case of a so-called top emission type display panel, light emitted from the light emitting layer passes through the cathode and the sealing layer and is extracted to the outside. For this reason, in addition to the high barrier performance with respect to gas, such as water vapor | steam, high light transmittance is requested | required of the sealing layer. Examples of such a material having both high barrier performance and light transmittance include silicon nitride (SiN) (see, for example, Patent Documents 1 and 2).

JP 2011-231357 A JP 2011-227369 A

  In order to prevent a gas such as water vapor from coming into contact with the light emitting functional layer, the sealing layer preferably has higher adhesion at the interface between the cathode and the sealing layer and the barrier performance of the sealing layer.

  In order to solve the above problems, a method for manufacturing a display panel according to one embodiment of the present invention provides a panel intermediate in which a first electrode, a light emitting functional layer, and a second electrode made of a conductive oxide are stacked in this order. A step of forming a buffer layer mainly composed of the first compound on the reduced second electrode by a reactive film-forming method in a state in which the reduction treatment is performed on the second electrode, and a buffer Forming a sealing layer containing the second compound as a main component on the buffer layer by a reactive film formation method in a state in which the reduction treatment is performed on the layer. It is an oxide of a compound.

  According to this structure, by having the said 2nd process, the chemical bond of the oxide which comprises a 2nd electrode, and the 1st compound which comprises a sealing layer is formed in the interface of a 2nd electrode and a buffer layer. By having the third step, the chemistry of the second compound formed by performing reduction treatment on the buffer layer at the interface between the buffer layer and the sealing layer and the second compound constituting the sealing layer A bond is formed. As a result, the bonding strength between the second electrode and the buffer layer and between the buffer layer and the sealing layer is increased, so that the adhesion between the second electrode and the sealing layer is improved. Can be prevented.

1 is a block diagram schematically showing an overall configuration of a display device according to Embodiment 1. FIG. 4 is a partially enlarged view of the display panel according to Embodiment 1. FIG. FIG. 3 is a partial cross-sectional view obtained by breaking along the line AA in FIG. 2 in the display panel according to the first embodiment. 5 is a partial cross-sectional view of the display panel for illustrating a manufacturing process of the display panel according to Embodiment 1. FIG. 5 is a partial cross-sectional view of the display panel for illustrating a manufacturing process of the display panel according to Embodiment 1. FIG. 5 is a partial cross-sectional view of the display panel for illustrating a manufacturing process of the display panel according to Embodiment 1. FIG. 5 is a cross-sectional view of the main part of the display panel for illustrating a manufacturing process of the display panel according to Embodiment 1. FIG. 5 is a cross-sectional view of the main part of the display panel for illustrating a manufacturing process of the display panel according to Embodiment 1. FIG. 6 is a partial cross-sectional view of a display panel according to Embodiment 2. FIG. FIG. 10 is a main-portion cross-sectional view of the display panel for illustrating a manufacturing process of the display panel according to the second embodiment. 12 is a schematic diagram for explaining a manufacturing process for the display panel according to Embodiment 2. FIG. 12 is a schematic diagram for explaining a manufacturing process for the display panel according to Embodiment 2. FIG.

<Outline of display panel manufacturing method and display panel according to one embodiment of the present invention>
A method for manufacturing a display panel according to one embodiment of the present invention includes a step of preparing a panel intermediate body in which a first electrode, a light emitting functional layer, and a second electrode made of a conductive oxide are stacked in order, A process of forming a buffer layer mainly composed of a first compound on the reduced second electrode by a reactive film-forming method in a state where the reduction process is performed on the reduced layer, and a reduction process on the buffer layer And forming the sealing layer containing the second compound as a main component on the buffer layer by a reactive film formation method. The first compound is an oxide of the second compound. is there.

  According to this structure, by having the said 2nd process, the chemical bond of the oxide which comprises a 2nd electrode, and the 1st compound which comprises a sealing layer is formed in the interface of a 2nd electrode and a buffer layer. By having the third step, the chemistry of the second compound formed by performing reduction treatment on the buffer layer at the interface between the buffer layer and the sealing layer and the second compound constituting the sealing layer A bond is formed. As a result, the bonding strength between the second electrode and the buffer layer and between the buffer layer and the sealing layer is increased, so that the adhesion between the second electrode and the sealing layer is improved. Can be prevented.

  In addition, according to this configuration, since the first compound is an oxide of the oxide of the second compound, a reduction treatment is performed on the buffer layer, so that a part of the buffer layer and the sealing layer are separated from each other. It is composed of one compound. As a result, the refractive index of the buffer layer can be brought close to the refractive index of the sealing layer, so that the scattering loss when light emitted from the light emitting functional layer is transmitted in the order of the cathode, the buffer layer, and the sealing layer is reduced. can do. Therefore, the light extraction efficiency from the light emitting functional layer to the outside of the display panel can be improved.

In the display panel manufacturing method according to one aspect of the present invention, in the reduction treatment for the buffer layer, substantially all of the first compound in the buffer layer is reduced to the second compound. Also good.
According to this configuration, the buffer layer and the sealing layer are configured of the first compound by reducing all of the first compound constituting the buffer layer to the second compound by reduction treatment. Become. Thereby, since the refractive index of the buffer layer becomes equal to the refractive index of the sealing layer, it is possible to eliminate the scattering loss when the light emitted from the light emitting functional layer is transmitted in the order of the cathode, the buffer layer, and the sealing layer. it can. Therefore, it is possible to improve the light extraction efficiency from the light emitting functional layer to the outside through the sealing portion.

In the method for manufacturing a display panel according to one aspect of the present invention, in the reduction treatment for the buffer layer, a region close to the sealing layer in the thickness direction of the buffer layer is reduced, and a region close to the second electrode May not be reduced.
The display panel manufacturing method according to one embodiment of the present invention may be one in which NH ₃ plasma is irradiated in the reduction treatment in the third step.

The method for manufacturing a display panel according to one embodiment of the present invention further includes a step of forming a sub-buffer layer containing a third compound as a main component on the sealing layer by a reactive film formation method,
Forming a sub-encapsulation layer containing a fourth compound as a main component on the sub-buffer layer in a state where the sub-buffer layer is subjected to a reduction treatment, and a third compound. May be an oxide of the second compound.

  According to this configuration, in addition to the buffer layer and the sealing layer, the sub buffer layer and the sub sealing layer are further formed. Thereby, the sealing performance of the light emitting functional layer and the cathode can be improved. Further, since the third compound is an oxide of the second compound, the bonding strength can be increased as compared with the case where the third compound is other than the oxide of the second compound. Then, by performing the reduction treatment in the fifth step, a chemical bond between the compound constituting the sub-buffer layer and the compound constituting the sub-sealing layer is formed at the interface between the sub-buffer layer and the sub-sealing layer. . As a result, the bonding strength between the sub-buffer layer and the sub-sealing layer is increased, so that the adhesion between the sub-buffer layer and the sub-sealing layer is improved. Therefore, peeling of the sub buffer layer and the sub sealing layer from the sealing layer can be suppressed.

In the method for manufacturing a display panel according to one embodiment of the present invention, the fourth compound may include an oxide as a main component.
In the method for manufacturing a display panel according to one embodiment of the present invention, the second electrode is made of an ITO film, the first compound is silicon oxynitride, and the second compound is silicon nitride. Also good.

In the method for manufacturing a display panel according to one embodiment of the present invention, the reactive film formation method employed in the fifth step may be an ALD method.
According to this configuration, the sub sealing layer is formed by the ALD method. Thereby, the sealing performance of the light emitting functional layer and the first and second electrodes can be improved.
The display panel according to one embodiment of the present invention includes a first electrode, a light-emitting functional layer formed over the first electrode, a second electrode formed of a conductive oxide and formed over the light-emitting functional layer, A buffer layer that is formed on the second electrode and covers the surface of the second electrode; and a sealing layer that is formed on the buffer layer and covers the surface of the buffer layer. At least the main component of the region located in the vicinity of the sealing layer and the main component of the sealing layer are the same compound, and chemical bonds are present at the interface between the second electrode and the buffer layer and the interface between the buffer layer and the sealing layer. Is formed.

In the display panel according to one embodiment of the present invention, the main component of substantially the entire region of the buffer layer and the main component of the sealing layer may be the same compound.
The display panel according to one embodiment of the present invention includes a main component of a region located in the vicinity of the sealing layer between the region located in the vicinity of the sealing layer and the sealing layer in the buffer layer. A layer containing an oxide as a main component is located.

In the display panel according to one embodiment of the present invention, the second electrode may be made of an ITO film, the first compound may be silicon oxynitride, and the second compound may be silicon nitride.
In addition, a display panel according to one embodiment of the present invention is formed over the sealing layer, and includes a sub-buffer layer that covers the surface of the sealing layer, a fourth compound, and is formed over the sub-buffer layer. A sub-sealing layer covering the surface of the sub-buffer layer, wherein the main component of the sub-buffer layer and the main component of the buffer layer are the same compound, and the interface between the sealing layer and the sub-buffer layer and the sub-buffer A chemical bond is formed at the interface between the layer and the sub sealing layer.

In the display panel according to one embodiment of the present invention, the second electrode may be light transmissive.
In the display panel according to one embodiment of the present invention, the sub sealing layer may contain an oxide as a main component.
In the display panel according to one embodiment of the present invention, in the thickness direction of the buffer layer, the ratio of one constituent element of the compound that is the main component of the buffer layer increases as the distance from the sealing layer increases. It may be.

Further, in the display panel according to one embodiment of the present invention, in the thickness direction of the sub buffer layer, the closer to the sub sealing layer, the larger the ratio of one constituent element of the compound that is the main component of the sub buffer layer. It may be.
<Embodiment 1>
<1> Configuration The configuration of the display device according to the present embodiment will be described.

1. Display Device FIG. 1 is a block diagram schematically showing an overall configuration of a display device 1 according to the present embodiment.
As shown in the figure, the display device 1 includes a display panel 10 having a rectangular shape in plan view, and a drive control unit 20 connected thereto.
The display panel 10 is, for example, an organic EL type that utilizes an electroluminescence phenomenon of an organic material and is a top emission type display panel. The display panel 10 is not limited to the organic EL type, and may be an inorganic EL type using an electroluminescent phenomenon of an inorganic material. Further, the display panel 10 is not limited to the top emission type, and may be a bottom emission type.

  The drive control unit 20 includes four drive circuits 21, 22, 23, and 24 and a control circuit 25 that controls the drive circuits 21, 22, 23, and 24. Each drive circuit 21, 22, 23, 24 is arranged along each side of the display panel 10. The arrangement of the drive circuits 21, 22, 23, 24 and the control circuit 25 in the drive control unit 20 is not limited to the arrangement shown in FIG. Further, the number of drive circuits is not limited to four. Further, in the drive control unit 20 shown in FIG. 1, the drive circuits 21, 22, 23, and 24 and the control circuit 25 are separated. For example, the control circuit and the drive circuit are one circuit. It may be constituted by.

An enlarged view of a part of the display panel 10 is shown in FIG. In FIG. 2, one direction along the surface of the display panel 10 is an X-axis direction, and a direction along the surface of the display panel 10 and orthogonal to the X-axis direction is a Y direction.
A plurality of pixels (pixels) are arranged in a matrix on the display panel 10. Each pixel is composed of a plurality of (three in FIG. 2) subpixels arranged in the X-axis direction. The emission colors of these three subpixels are red (R), green (G), and blue (B). This one subpixel corresponds to one light emitting element.

2. Display Panel Next, the configuration of the display panel 10 will be described.
FIG. 3 shows a partial cross-sectional view obtained by breaking the display panel 10 along the line AA in FIG. 3, the X-axis direction is synonymous with the X-axis direction in FIG. 2, and the direction orthogonal to the X-axis and the Y-axis, that is, the thickness direction of the display panel 10 is the Z-axis direction.

An anode (also referred to as “first electrode”) 107 is formed on the substrate 101 in units of subpixels. Hereinafter, in this specification, the direction in which various functional layers are stacked on the substrate 101 is referred to as the upward direction with the substrate 101 as a reference. This upward direction is the Z direction in FIG.
A hole injection layer 109 is formed on a region of the substrate 101 where the anode 107 is not formed and on the anode 107. That is, the hole injection layer 109 is formed so as to cover substantially the entire surface of the substrate 101 on which the anode 107 is formed. The hole injection layer 109 is in a state where a region corresponding to between the anodes 107 is depressed.

Banks (partition walls) 111 are formed in a region corresponding to the space between the anodes 107 on the hole injection layer 109.
The bank 111 fills a depressed region corresponding to the gap between the anodes 107 in the hole injection layer 109 and protrudes upward from the hole injection layer 109 existing on the upper surface of the peripheral portion of the anode 107. The cross-sectional shape of the bank 111 is a trapezoid whose width becomes narrower upward. The bank 111 is formed so as to surround each of the anodes 107 having a substantially rectangular shape in plan view. In other words, the bank 111 is formed in a grid shape surrounding each anode 107 in plan view.

A predetermined light color (the above-described red, green, and blue) is applied to each of the regions on the hole injection layer 109 that are divided by the banks 111 (regions corresponding to adjacent banks 111 in FIG. 3). A light emitting layer 113 is formed.
An electron transport layer 115 is formed on the light emitting layer 113. The electron transport layer 115 covers not only the light emitting layer 113 but also the entire portion of the bank 111 protruding above the light emitting layer 113. A cathode (also referred to as “second electrode”) 117 is formed on the electron transport layer 115, and a sealing portion 119 is formed on the cathode 117. Here, the cathode 117 is formed so as to cover the entire electron transport layer 115, and the sealing portion 119 is formed so as to cover the entire cathode 117.

The three layers including the hole injection layer 109, the light emitting layer 113, and the electron transport layer 115 are referred to as “light emitting functional layers”.
3. Details of Each Configuration Hereinafter, each configuration of the display panel 10 described above will be described in detail.
(1) Substrate The substrate 101 includes a TFT substrate 103 and an insulating film 105 formed on the TFT substrate 103.

  The TFT substrate 103 includes a substrate body, a TFT (Thin Film Transistor) formed on the substrate body, a wiring member, and a passivation film that covers the TFT. In FIG. 3, the illustration of the TFT, the wiring member, the passivation film, and the like is omitted. The substrate body is, for example, alkali-free glass, soda glass, non-fluorescent glass, phosphate glass, borate glass, quartz, acrylic resin, styrene resin, polycarbonate resin, epoxy resin, polyethylene, polyester, silicone resin Or made of an insulating material such as alumina. Moreover, this board | substrate body may consist of an organic resin film, for example.

The insulating film 105 is a so-called flattening film for flattening the surface step of the TFT substrate 103. The insulating film 105 is made of an insulating material such as polyimide resin or acrylic resin. This insulating film 105 is interposed between the TFT substrate 103 and the anode 107 and the hole injection layer 109, and is also referred to as an interlayer insulating film.
(2) Anode The anode 107 is made of aluminum (Al) or an aluminum alloy. The anode 107 may be formed of, for example, silver (Ag), an alloy of silver, palladium (Pd), and copper (Cu), an alloy of silver, rubidium (Rb), and gold (Au), molybdenum (Mo), and chromium ( It may be formed of an alloy of Cr), an alloy of nickel (Ni) and chromium, or the like.

Here, the thickness of the anode 107 is set to, for example, 100 [nm] to 200 [nm].
(3) Hole Injection Layer The hole injection layer 109 has a function of promoting hole injection into the light emitting layer 113. The hole injection layer 109 is formed of a metal oxide including an oxide of a transition metal such as tungsten oxide (WO _x ), molybdenum oxide (MoO _x ), molybdenum oxide tungsten (Mo _x W _y O _z ), for example. .

Here, the thickness of the hole injection layer 109 is set to, for example, 1 [nm] to 10 [nm].
(4) Bank The bank 111 has a function of partitioning adjacent subpixels. The bank 111 is formed using a negative resist made of a photosensitive and insulating acrylic resin. The material for forming the bank 111 is not limited to an acrylic resin, and may be a polyimide resin, a novolac type phenol resin, or the like. Further, the bank 111 is not limited to a negative resist, and may be formed using a positive resist, or may be a resin material having no photosensitivity.

The bank 111 preferably has organic solvent resistance. Furthermore, since the bank 111 is subjected to an etching process, a heating process (post-baking process or a baking process), the bank 111 is formed of a highly resistant material that does not excessively deform or alter the process. It is preferable.
Here, the height of the bank 111 from the upper surface of the hole injection layer 109 is set to 1 [um] to 2 [um], for example.

(5) Light emitting layer The light emitting layer 113 is formed of an organic material. Examples of the organic material include polymer materials such as polyfluorene, polyphenylene vinylene, polyacetylene, polyphenylene, polyparaphenylene ethylene, poly-3-hexylthiophene, and derivatives thereof, and JP-A-5-163488. Oxinoid compounds, perylene compounds, coumarin compounds, azacoumarin compounds, oxazole compounds, oxadiazole compounds, perinone compounds, pyrrolopyrrole compounds, naphthalene compounds, anthracene compounds, fluorene compounds, fluoranthene compounds, tetracene compounds, pyrene compounds, coronene compounds, Quinolone compounds and azaquinolone compounds, pyrazoline derivatives and pyrazolone derivatives, rhodamine compounds, chrysene compounds, phenanthrene compounds, cyclopentadiene Compound, stilbene compound, diphenylquinone compound, styryl compound, butadiene compound, dicyanomethylenepyran compound, dicyanomethylenethiopyran compound, fluorescein compound, pyrylium compound, thiapyrylium compound, selenapylium compound, telluropyrylium compound, aromatic ardadiene compound, oligophenylene Fluorescent substances such as compounds, thioxanthene compounds, cyanine compounds, acridine compounds, metal complexes of 8-hydroxyquinoline compounds, metal complexes of 2-bipyridine compounds, complexes of Schiff salts with Group III metals, oxine metal complexes, rare earth complexes Can be mentioned.

Here, the thickness of the light emitting layer 113 is set to, for example, 10 [nm] to 100 [nm].
(6) Electron transport layer The electron transport layer 115 is formed of an organic material. Examples of the organic material include nitro-substituted fluorenone derivatives, thiopyrandioxide derivatives, diphequinone derivatives, perylene tetracarboxyl derivatives, anthraquinodimethane derivatives, fluorenylidenemethane described in JP-A-5-163488. Derivatives, anthrone derivatives, oxadiazole derivatives, perinone derivatives, quinoline complex derivatives. In this embodiment mode, the organic material is doped with barium (Ba). Thereby, the electron transport layer 115 has a function of promoting the injection of electrons into the light emitting layer 113. Note that the material doped into the organic material to give an electron injection function to the electron transport layer 115 is not limited to barium. For example, other alkali metals such as sodium (Na) and potassium (K) or the like Alkaline earth metals may be used.

Here, the thickness of the electron transport layer 115 is set to, for example, 0.5 [nm] to 50 [nm].
(7) Cathode The cathode 117 is an electrode for injecting electrons into the light emitting functional layer. The display panel 10 according to the present embodiment is a so-called top emission type. Therefore, the cathode 117 needs to use a material transparent to the light emitted from the light emitting layer 113. Examples of such materials include materials used for so-called transparent electrodes, such as ITO (Indium Tin Oxide) and IZO (Indium Zinc Oxide).

Here, the thickness of the cathode 117 is set to, for example, 10 [nm] to 200 [nm].
(8) Sealing portion The sealing portion 119 has a function of preventing the light emitting functional layer, the cathode 117, and the like from being exposed to moisture or air.
The sealing unit 119 includes a buffer layer 121 and a sealing layer 123 formed on the buffer layer 121.

As shown in the enlarged view of the circled portion A1 in FIG. 3, the buffer layer 121 is composed of two layered regions 121a and 121b. Here, examples of the material for forming the region 121a include compounds such as silicon oxynitride (SiON), carbon-containing silicon oxide (SiOC), and aluminum oxynitride (Al _X O _Y N _Z ). Examples of the material for forming the sealing layer 123 and the region 121b include compounds such as silicon nitride (SiN), silicon carbide (SiC), and aluminum nitride (AlN).

Here, the thickness of the buffer layer 121 is set to, for example, 1 [nm] to 5 [nm]. The film thickness of the sealing layer 123 is set to, for example, 100 [nm] to 1000 [nm].
The compound (first compound) constituting the region 121a of the buffer layer 121 is preferably an oxide of the compound (second compound) constituting the region 121b. For example, when the material forming the region 121b is SiN, the material forming the region 121a is preferably SiON. In this case, the buffer layer 121 including the region 121a made of SiON and the region 121b made of SiN is formed by reducing the film made of SiON. Accordingly, the effective refractive index of the entire buffer layer 121 can be made close to the refractive index of the sealing layer 123, so that light emitted from the light emitting functional layer is emitted from the cathode 117, the buffer layer 121, and the sealing layer 123. It is possible to reduce the scattering loss when sequentially transmitting. Therefore, the light extraction efficiency from the light emitting functional layer to the outside of the display panel 10 can be improved.

<2> Manufacturing Method Next, a manufacturing process of the display panel 10 according to the present embodiment will be described.
4 to 6 are diagrams showing a manufacturing process of the display panel 10. 4 to 6 schematically show a part of the display panel 10 extracted.
The manufacturing process of the display panel 10 includes (1) a process of forming an anode (anode formation process), (2) a process of forming a hole injection layer (hole injection layer formation process), and (3) a process of forming a bank. (Bank forming step), (4) Step of forming a light emitting layer (light emitting layer forming step), (5) Step of forming an electron transport layer (electron transport layer forming step), (6) Step of forming a cathode (cathode) Forming step), (7) reducing plasma treatment step (8) step of forming a buffer layer (buffer layer forming step), (9) reducing plasma treatment step, (10) step of forming a sealing layer (sealing) Layer forming step).

  In addition, there exists a process (board | substrate preparation process) of preparing the board | substrate 101 before said (1) anode formation process. Specifically, a step of forming the insulating film 105 on the TFT substrate 103 (insulating film forming step) and a wiring member formed on the TFT substrate 103 and the anode are electrically connected to the insulating film 105. This is a step of forming a contact hole (contact hole forming step). In the insulating film forming step, an acrylic resin or the like is applied by spin coating, and then heat treatment (baking treatment) is performed. In the contact hole forming step, a contact hole is formed using a well-known photolithography technique and etching technique.

In addition, the step of forming the light emitting functional layer, that is, the steps from (2) hole injection layer forming step to (5) electron transport layer forming step are collectively referred to as “light emitting functional layer forming step”.
Hereinafter, each process performed after a board | substrate preparation process is demonstrated in detail.
(1) Anode formation step On the substrate 101 prepared through the substrate preparation step, a metal film (here, an aluminum (Al) film) serving as a base of the anode 107 is formed. For forming the aluminum film, for example, a vacuum film forming method such as a sputtering method or a vacuum vapor deposition method can be used. After the metal film is formed, the metal film is patterned using a known photolithography technique and etching technique. Thereby, a plurality of anodes 107 are formed (see FIG. 4A).

(2) Hole Injection Layer Formation Step After the anode formation step, the hole injection layer 109 is formed on the upper surface side of the substrate 101 (see FIG. 4B). The hole injection layer 109 is made of a metal oxide film (here, a tungsten oxide (WOx) film). For forming the tungsten oxide film, for example, a vacuum film forming method such as a sputtering method or a vacuum evaporation method can be used. For example, a composition containing tungsten oxide (WOx) or tungsten is used to form a tungsten oxide film using this vacuum film formation method.

(3) Bank Formation Step After the hole injection layer formation step, a bank material layer (not shown) that forms the base of the bank 111 is formed on the hole injection layer 109. The bank material layer is composed of a negative resist. This bank material layer is formed, for example, by applying heat treatment (pre-bake treatment) after applying by spin coating.

After the bank material layer is formed, ultraviolet rays are irradiated from above the photomask with the photomask superimposed on the bank material layer. In this photomask, a pattern is formed so as to shield the region other than the region where the bank 111 is to be formed in a state of being overlaid on the bank material layer. Therefore, only the area where the bank 111 is to be formed in the bank material layer can be exposed. Then, after exposing a part of the bank material layer, it is immersed in a developing solution (for example, TMAH aqueous solution) to remove an unnecessary bank material layer that is not exposed to light. Next, the developing solution is removed from the substrate 101 by washing with water, and then the substrate 101 is subjected to heat treatment (post-bake treatment and baking treatment) to form the bank 111 (see FIG. 4C). ). Thereafter, the substrate 101 is subjected to an oxygen plasma process or an etching process using CF ₄ to perform a water repellent process on the bank 111.

(4) Light-Emitting Layer Formation Step Ink made of a composition containing a light-emitting material is dropped into each region partitioned by the bank 111 by, for example, an inkjet method. Then, the light emitting layer 113 is formed by drying the ink (see FIG. 5A).
(5) Electron Transport Layer Forming Step After the light emitting layer forming step, the electron transport layer 115 is formed on the light emitting layer 113 (see FIG. 5B). The electron transport layer 115 is made of, for example, a nitro-substituted fluorenone derivative. For the formation of the electron transport layer 115, a vacuum deposition method or a spin coating method can be used. After the electron transport layer 115 is formed, the electron transport layer 115 is doped with about 2 to 30 wt% of barium (Ba) in order to improve the electron injection property of the electron transport layer 115.

(6) Cathode formation step After the electron transport layer formation step, a cathode 117 is formed on the electron transport layer 115 (see FIG. 5C). The cathode 117 is made of a transparent metal oxide film (here, an ITO film). The ITO film is formed by a chemical vapor deposition (CVD) method. As a CVD method, either a thermal CVD method or a plasma CVD method may be used. Moreover, you may use vacuum film-forming methods, such as sputtering method and a vacuum evaporation method, for ITO film | membrane.

(7) Reducing Plasma Treatment Step After the cathode forming step, the substrate 101 on which the cathode 117 is formed is exposed to a reducing plasma atmosphere. Here, NH ₃ plasma can be used as the reducing plasma. Further, the exposure time to the reducing plasma atmosphere is several seconds to several tens of seconds. Note that the reducing plasma atmosphere is predominantly composed of reactive species such as hydrogen radicals and carbon monoxide (CO ₂ ), such as radicals, ions, atoms, and molecules that have a reducing action, that is, an action of extracting oxygen. It means an atmosphere to do. In addition, radicals and ions include atomic or molecular radicals or ions. Further, the reducing plasma atmosphere may contain not only a single reactive species but also a plurality of reactive species. For example, an atmosphere in which hydrogen radicals and NH ₂ radicals are mixed may be used. Also referred to as a NH ₃ plasma, it does not mean a complete NH ₃ plasma, impurity gases NH ₃ in the plasma (nitrogen, oxygen, carbon dioxide, water vapor, etc.) may have contained, or, Other dilution gas and additive gas may be contained in the NH ₃ plasma.

FIG. 7 and FIG. 8 show cross-sectional views after each step from the (7) reducing plasma treatment step to the (10) sealing layer forming step in the circled portion A1 in FIG.
As shown in FIG. 7A, after the reducing plasma treatment step, in the region 117b near the upper surface of the cathode 117, the dangling bonds (unpaired) are accompanied by the desorption of oxygen atoms from the cathode 117 made of the ITO film. Many In atoms and Sn atoms having electrons) are generated. The depth of the region 117b in the vicinity of the upper surface of the cathode 117 depends on the time when the cathode 117 is exposed to NH ₃ plasma. In the cathode 117, a region 117b in which oxygen atoms are deficient in the vicinity of the upper surface and a region 117a in which oxygen atoms are not deficient are generated.

(8) Buffer Layer Formation Step After the reducing plasma treatment step, the buffer layer 121 is formed (see FIG. 7B). The buffer layer 121 is made of an oxide film (here, a silicon oxynitride (SiON) film). The SiON film is formed by a CVD method which is a kind of reactive film forming method. Here, the “reactive film formation method” means a film formation method in which a chemical reaction occurs on the surface of the film formation target. As a CVD method, either a thermal CVD method or a plasma CVD method may be used. Alternatively, a reactive sputtering method may be used.

By the way, in the region 117b near the upper surface of the cathode 117, there are many In atoms and Sn atoms having unpaired electrons, and these In atoms and Sn atoms are separated from oxygen atoms in the buffer layer 121 made of the SiON film. It is easy to form a covalent bond which is a kind of chemical bond.
On the other hand, when the buffer layer 121 is formed after the cathode formation step without passing through the reducing plasma treatment step, the region 117b near the upper surface of the cathode 117 has almost no In atoms or Sn atoms having unpaired electrons. .

  That is, in the manufacturing method according to the present embodiment, an In atom that easily forms a covalent bond with an oxygen atom in the buffer layer 121 in the region 117b in the vicinity of the upper surface of the cathode 117 through the reducing plasma treatment step. And many Sn atoms can be generated. Therefore, compared to the case where the buffer layer 121 is formed without going through the reducing plasma treatment step, there are more covalent bonds between In atoms and Sn atoms in the cathode 117 and oxygen atoms in the buffer layer 121. In addition, the adhesion between the cathode 117 and the buffer layer 121 is improved.

(9) Reducing Plasma Treatment Step After the buffer layer forming step, the substrate 101 on which the buffer layer 121 is formed is exposed to a reducing plasma atmosphere. Here, NH ₃ plasma can be used as the reducing plasma. Further, the exposure time to the reducing plasma atmosphere is several seconds to several tens of seconds. Note that the meanings of the reducing plasma atmosphere and the NH ₃ plasma are the same as those described in the above (7), and thus detailed description thereof is omitted here.

As shown in FIG. 7C, after the reducing plasma treatment step, Si atoms and N atoms having dangling bonds (unpaired electrons) are released along with the desorption of oxygen atoms from the buffer layer 121 made of the SiON film. Many occur. The depth of the region where dangling bonds are generated in the buffer layer 121 depends on the time when the buffer layer 121 is exposed to NH ₃ plasma. In the buffer layer 121, oxygen atoms are desorbed in almost the entire region 121 b of the buffer layer 121, that is, in the entire region 121 b other than the region 121 a in which a covalent bond containing oxygen is formed at the interface with the cathode 117. Thus, silicon nitride (SiN, hereinafter referred to as reduced SiN) composed of Si atoms and N atoms having unpaired electrons exists.

(10) Sealing layer forming step After the reducing plasma treatment step, the sealing layer 123 is formed (see FIG. 8). The sealing layer 123 is made of a semiconductor compound film (here, a SiN film). The SiN film is formed by a CVD method which is a kind of reactive film forming method. As a CVD method, either a thermal CVD method or a plasma CVD method may be used. Alternatively, a reactive sputtering method may be used.

By the way, a large amount of reduced SiN exists in the region 121b in the vicinity of the upper surface of the buffer layer 121, and Si atoms and N atoms constituting the reduced SiN are Si atoms and N atoms in the sealing layer 123 made of the SiN film. It is easy to form a covalent bond that is a kind of chemical bond with an N atom.
On the other hand, when the sealing layer 123 is formed after the buffer layer forming step without passing through the reducing plasma processing step, the reduced SiN is hardly present in the region 121b near the upper surface of the buffer layer 121.

  That is, in the manufacturing method according to the present embodiment, a large amount of reduced SiN can be generated in the region 121b near the upper surface of the buffer layer 121 through the reducing plasma treatment process. Therefore, compared with the case where the sealing layer 123 is formed without going through the reducing plasma treatment step, Si atoms and N atoms constituting the reduced SiN in the buffer layer 121 and Si atoms constituting the sealing layer 123 are formed. In addition, many covalent bonds, which are a kind of chemical bonds with N atoms, are generated, and the adhesiveness between the buffer layer 121 and the sealing layer 123 is improved accordingly.

<3> Summary As described above, the method for manufacturing the display panel 10 according to the present embodiment is formed by laminating the anode (first electrode) 107, the light emitting functional layer, and the cathode (second electrode) 117 made of ITO in this order. This is a display panel manufacturing method in which the display panel 10 is manufactured by forming a sealing layer 123 that seals the cathode 117 by covering the upper portion of the cathode 117 on the panel intermediate. Then, after reducing the cathode 117 in the reducing plasma processing step, the buffer layer 121 made of SiON (first compound) is formed by the CVD method in the buffer layer forming step. At this time, ITO and It is covalently bonded to SiON. Next, after the reduction process is performed on the buffer layer 121 in the reducing plasma processing step, the sealing layer 123 made of SiN (second compound) is formed in the sealing layer forming step. At this time, reduced SiN and SiN are covalently bonded. As a result, the bonding strength between the cathode 117 and the buffer layer 121 and between the buffer layer 121 and the sealing layer 123 is increased, so that the adhesion between the cathode 117 and the sealing layer 123 is improved, and the cathode of the sealing layer 123 is improved. Separation from 117 can be suppressed. As a result, it is possible to suppress the occurrence of dark spots in a part of the display panel 10 and improve the display quality of the display panel 10. In addition, the adhesion between the cathode and the sealing layer is improved as compared with the conventional configuration in which the sealing layer made of the SiN film is directly formed on the cathode made of the ITO film.

  By improving the adhesion at the interface between the sealing layer and the cathode, the sealing layer can be made difficult to peel from the cathode. In particular, when a conductive oxide film such as an ITO film is employed as the cathode, in the configuration in which the sealing layer made of SiN is formed directly on the cathode, the sealing layer from the cathode becomes thicker to some extent. Peeling tends to occur easily. The cathode extends to the periphery of the display panel in order to be electrically connected to a drive circuit arranged outside the display panel. Therefore, by improving the adhesion between the sealing layer and the cathode, a part of the sealing layer is peeled off from the cathode, and a gas such as water vapor reaches the cathode surface through the peeling portion from the peripheral edge of the display panel. Adsorption or intrusion to the light emitting functional layer can be suppressed. As a result, the cathode and the light emitting functional layer are deteriorated, and the deterioration of display quality of the display panel can be suppressed.

Further, SiON constituting the buffer layer 121 is an oxide of SiN constituting the sealing layer 123.
Then, by performing the reduction plasma treatment step before the sealing layer forming step, almost the entire region on the sealing layer 123 side of the buffer layer 121 is composed of SiN.
Accordingly, the effective refractive index of the entire buffer layer 121 can be made close to the refractive index of the sealing layer 123, so that light emitted from the light emitting functional layer is emitted from the cathode 117, the buffer layer 121, and the sealing layer 123. It is possible to reduce the scattering loss when sequentially transmitting.

Further, SiN constituting the sealing layer has a higher gas barrier property than SiON constituting the buffer layer 121. Therefore, the sealing part in which the buffer layer 121 on the cathode 117 is reduced and the sealing layer 121 is formed of SiN can improve the gas barrier property more than the sealing part in which all of the sealing layer 121 is formed of SiON.
Therefore, the gas barrier property can be enhanced and the light extraction efficiency of the light emitted from the light emitting functional layer to the outside of the display panel 10 can be improved.

Here, in the buffer layer 121 between the cathode 117 and the sealing layer 123, only the upper layer portion close to the sealing layer 123 may be reduced to be SiN.
The sealing layer 123 made of SiN has a low thermal expansion coefficient and low stretchability. Therefore, in the case where the sealing layer made of the SiN film is formed directly on the cathode made of the ITO film as in the prior art, the sealing layer 123 is caused by the difference in the thermal expansion coefficient between the ITO film and the SiN film. May be peeled off from the cathode 117 or the sealing layer 123 may be cracked.

  Since the buffer layer 121 between the cathode 117 and the sealing layer 123 includes a region made of SiON, in the region 121a of the buffer layer 121, stress caused by the difference in thermal expansion coefficient between the ITO film and the SiN film is generated. Alleviated. Therefore, there is an advantage that the peeling of the sealing layer 123 from the cathode 117 and the generation of cracks in the sealing layer 123 can be suppressed as compared with the above-described conventional configuration.

Further, since the stress relaxation region made of SiON formed in the buffer layer 121 is formed by reducing only a part of the buffer layer 121, the stress relaxation region made of SiON and the buffer layer 121 The bonding force of the region made of SiN is strong.
Therefore, the stress relaxation region includes a layer made of SiON and a layer made of SiN (stress compared to a sealing portion in which a layer made of SiON is formed on the cathode 117 and the cathode 117 and further a layer made of SiN is formed thereon. The bonding strength of the relaxation layer can be increased.

Accordingly, stress generated between the cathode 117 and the sealing layer 123 can be relaxed while keeping the strength of the sealing portion high.
In the first embodiment, the buffer layer is made of SiON (first compound) and the sealing layer is made of SiN (second compound). However, impurities such as hydrogen may be contained in the buffer layer and the sealing layer, and the main component of the buffer layer may be the first compound and the main component of the sealing layer may be the second compound.

<Embodiment 2>
FIG. 9 shows a partial cross-sectional view of display panel 210 according to the present embodiment.
The display panel 210 is different from the display panel 10 according to Embodiment 1 in the structure of the sealing portion 219. In addition, about the structure similar to the display panel 10 which concerns on Embodiment 1, the same code | symbol is attached | subjected and description is abbreviate | omitted suitably.

The sealing unit 219 includes a buffer layer 121, a sealing layer 123 formed on the buffer layer 121, a sub-buffer layer 211 formed on the sealing layer 123, and a sub-layer formed on the sub-buffer layer 211. And a sealing layer 213.
Here, examples of the material for forming the sub buffer layer 211 include silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), silicon carbide (SiC), carbon-containing silicon oxide (SiOC), and nitride. Examples thereof include semiconductor compounds and metal compounds such as aluminum (AlN) and aluminum oxide (Al ₂ O ₃ ). Examples of the material for forming the sub sealing layer 213 include silicon nitride (SiN), aluminum oxide (Al ₂ O ₃ ), silicon oxide (SiO ₂ ), aluminum nitride (AlN), and aluminum oxynitride (Al _X Examples thereof include semiconductor compounds such as O _Y N _Z ) and metal compounds.

  Here, the sub buffer layer 211 is preferably an oxide of a compound constituting the sealing layer 123. For example, when the material forming the sealing layer 123 is SiN, the material forming the sub buffer layer 211 is preferably SiON. This is because the sub-buffer layer 211 and the sealing layer 123 are made of SiN by performing a reduction process on the sub-buffer layer 123. Then, since the effective refractive index of the entire sub-buffer layer 211 can be made close to the refractive index of the sealing layer 123, the light emitted from the light emitting functional layer is emitted from the cathode 117, the buffer layer 121, and the sealing layer 123. It is possible to reduce the scattering loss when sequentially transmitting.

As in the buffer layer of the first embodiment, only the upper part of the sub buffer layer 211 may be reduced to SiN, and the lower part may have SiON remaining thereon.
Since the sub-buffer layer 211 between the sub-sealing layer 213 and the sealing layer 123 includes a region made of SiON, the sub-buffer layer 211 has a difference in thermal expansion coefficient between the sub-sealing layer 213 and the sealing layer 123. It is possible to relieve the stress caused by the above.

Next, the manufacturing process of the display panel 210 according to the present embodiment will be described.
The manufacturing process of the display panel 210 includes (1) a process of forming an anode (anode formation process), (2) a process of forming a hole injection layer (hole injection layer formation process), and (3) a process of forming a bank. (Bank forming step), (4) Step of forming a light emitting layer (light emitting layer forming step), (5) Step of forming an electron transport layer (electron transport layer forming step), (6) Step of forming a cathode (cathode) Forming step), (7) reducing plasma treatment step (8) step of forming a buffer layer (buffer layer forming step), (9) reducing plasma treatment step, (10) step of forming a sealing layer (sealing) Layer forming step), (11) forming a sub-buffer layer (sub-buffer layer forming step), (12) reducing plasma treatment step, and (13) forming a sub-sealing layer (sub-sealing layer forming step). ). Note that, among the manufacturing processes of the display panel 210, (1) the anode forming process and (10) the sealing layer forming process are the same as those in Embodiment 1, and thus the description thereof is omitted here.

(11) Sub-buffer layer formation step FIG. 10 is a cross-sectional view after each step from the (7) reducing plasma treatment step to (10) the sealing layer formation step in the circled portion A2 in FIG. Shown in
After the sealing layer forming step, the sub buffer layer 211 is formed. The sub buffer layer 211 is made of a semiconductor oxide film (here, a silicon oxynitride (SiON) film). The SiON film is formed by a CVD method which is a kind of reactive film formation method (see FIG. 10A). As a CVD method, either a thermal CVD method or a plasma CVD method may be used. Alternatively, a reactive sputtering method may be used. Here, the thickness of the buffer layer 121 is set to, for example, 1 [nm] to 5 [nm].

(12) Reducing Plasma Treatment Step After the sub buffer layer forming step, the substrate 101 on which the sub buffer layer 211 is formed is exposed to a reducing plasma atmosphere (see FIG. 10B). Here, NH ₃ plasma can be used as the reducing plasma. Further, the exposure time to the reducing plasma atmosphere is several seconds to several tens of seconds. Note that the meanings of the reducing plasma atmosphere and the NH ₃ plasma are the same as those described in the first embodiment, and thus detailed description thereof is omitted here.

  After the reducing plasma treatment step, the region 211b including at least the vicinity of the upper surface of the sub-buffer layer 211 has dangling bonds (unpaired electrons) accompanying the desorption of oxygen atoms from the sub-buffer layer 211 made of the SiON film. Many Si atoms and N atoms are generated. On the other hand, on the side of the sealing layer 123 in the sub buffer layer 211, there is a region 121a in which oxygen atoms are not lost. Eventually, after the reducing plasma treatment step, oxygen atoms in the region 211b other than the region 211a including the vicinity of the interface with the sealing layer 123 are desorbed, and the region 211b is composed of Si atoms and N atoms having unpaired electrons. There will be silicon nitride (SiN, hereinafter referred to as reduced SiN).

(13) Subsealing layer forming step After the reducing plasma treatment step, the subsealing layer 213 is formed. The sub sealing layer 213 is made of a metal compound film (here, an Al ₂ O ₃ film). The Al ₂ O ₃ film is formed by an ALD (Atomic Layer Deposition) method. The ALD method is a method of forming a film for each atomic layer by alternately introducing reactants as raw materials for Al ₂ O ₃ into a reaction furnace of a film forming apparatus. As the ALD method, either a thermal ALD method or a plasma ALD method may be used. Here, the film thickness of the sealing layer 123 is set to, for example, 10 [nm] to 20 [nm].

Here, a method of forming the sub sealing layer 213 by the ALD method will be described in detail. Here, a case where trimethylaluminum (TMA) and water vapor (H ₂ O) are used as reactants will be described.
11 and 12 are schematic diagrams for explaining a method of forming the sub sealing layer 213 by the ALD method.

(13-1) First, H ₂ O is introduced into the reaction furnace of the film forming apparatus. Then, the reduced SiN in the vicinity of the upper surface of the sub sealing layer 213 is oxidized by H ₂ O molecules, and a large number of OH groups are generated on the surface of the sub sealing layer 213 (see FIG. 11A).
(13-2) Next, TMA molecules are supplied into the reactor. Then, the TMA molecules supplied to the surface of the sub buffer layer 211 react with OH groups on the surface of the sub buffer layer 211 to be chemically adsorbed on the surface of the sub buffer layer 211 (see FIG. 11B). At this time, TMA molecules remaining without being chemically adsorbed on the surface of the sub-buffer layer 211 and methane (CH ₄ ) generated by oxidation of the TMA molecules are floating in the reaction furnace.

(13-3) Subsequently, the inside of the reaction furnace is purged with an inert gas (for example, Ar) to remove TMA molecules and CH ₄ molecules floating in the reaction furnace. Here, “purging” means removing TMA molecules and CH ₄ molecules floating in the reaction furnace from the reaction furnace by repeatedly introducing an inert gas into the reaction furnace and evacuating the reaction furnace. That means.
(13-4) Thereafter, H ₂ O is introduced into the reaction furnace (see FIG. 11C). Then, the TMA molecules chemically adsorbed on the surface of the sub-buffer layer 211 react with H ₂ O molecules, and an Al ₂ O ₃ film for one atomic layer grows (see FIG. 12A). At this time, in the reaction furnace, H ₂ O molecules remaining without reacting with TMA molecules and CH 4 molecules generated by the reaction between TMA molecules and H ₂ O molecules are suspended.

(13-5) Next, the inside of the reaction furnace is purged with an inert gas (for example, Ar) to remove H2O molecules and CH4 molecules floating in the reaction furnace.
(13-6) Subsequently, TMA molecules are introduced into the reaction furnace. Then, TMA molecules react with O atoms on the Al ₂ O ₃ film surface, and TMA molecules chemically bond with O atoms of Al ₂ O ₃ (see FIG. 12B). At this time, TMA molecules remaining without reacting with O atoms on the surface of the Al ₂ O ₃ film and CH ₄ molecules generated by the reaction between O atoms and TMA molecules are floating in the reaction furnace. .

(13-7) Thereafter, the inside of the reaction furnace is purged with an inert gas (for example, Ar) to remove TMA molecules and CH ₄ molecules floating in the reaction furnace.
(13-8) Next, H ₂ O is introduced into the reaction furnace. Then, TMA molecules chemically adsorbed on the surface of the Al ₂ O ₃ film and H ₂ O molecules react to grow an Al ₂ O ₃ film for one atomic layer (see FIG. 12C).

Thereafter, by repeating steps (13-6) to (13-8), an Al ₂ O ₃ film is grown one atomic layer at a time.
In the present embodiment, as a reactant, has been described the case of using the TMA molecules and H ₂ O molecules, it is not limited thereto, for example, oxygen molecules instead of H ₂ O molecules (O ₂ ) or ozone (O ₃ ) may be used.

By the way, a large amount of reduced SiN exists in the region 211b near the upper surface of the sub buffer layer 211, and Si atoms and N atoms constituting these reduced SiN have dangling bonds, and the Al ₂ O ₃ film The reaction product (here, trimethylaluminum: TMA) containing Al atoms, which are constituent elements, is easily chemisorbed. Thereby, the chemical adsorption of TMA on the surface of the sub buffer layer 211 is promoted.

In the second embodiment, the sub-buffer layer is made of the third compound and the sub-sealing layer is made of the fourth compound. However, the sub-buffer layer and the sub-encapsulation layer may contain a sub-substance such as hydrogen and SiONHC, the main component of the sub-buffer layer is the third compound, and the main component of the encapsulating layer is the fourth compound. If it is.
<Modification>
(1) In the first embodiment, the SiN constituting the buffer layer 321 is such that the proportion of Si, which is a constituent element of SiN, increases toward the sealing layer 123 in the thickness direction of the buffer layer 321. Also good. That is, when the compound constituting the buffer layer 321 is Si _x N _y , the value of y may be smaller as it approaches the sealing layer 123 in the thickness direction of the buffer layer 321.

(2) In the second embodiment, a method for manufacturing the display panel 210 in which the SiON film is formed in the third sealing layer forming step and the Al ₂ O ₃ film is formed in the fourth sealing layer forming step is taken as an example. However, the present invention is not limited to this. For example, a SiO film may be formed in the fourth sealing layer forming step.
(3) In Embodiment 2, the example in which the sub sealing layer 213 is formed by the ALD method has been described. However, the method for forming the sub sealing layer 213 is not limited to this. For example, a CVD method may be adopted.

  (4) In the first and second embodiments, the manufacturing method of the sealing portions 119 and 219 constituting part of the display panels 10 and 210 has been described. However, the sealing portions 119 and 219 are one of the display panels 10 and 210. It is not limited to what constitutes the part. For example, a method for manufacturing a display panel that constitutes a passivation film of a semiconductor device having an electrode made of an oxide such as an ITO film may be used.

  (5) In Embodiments 1 and 2, the light-emitting functional layer has a three-layer structure including a hole injection layer 109 made of a metal oxide, a light-emitting layer 113 made of an organic material, and an electron transport layer 115 made of an organic material. However, the present invention is not limited to this structure. For example, the light emitting functional layer may be made of an inorganic material such as a compound semiconductor. In addition to the light emitting layer 113, the light emitting functional layer may include any functional layer such as the electron transport layer 115.

  The present invention can be suitably used for, for example, a method of manufacturing an organic EL display panel used as a home or public facility, or various display devices for business use, television devices, displays for portable electronic devices, and the like.

DESCRIPTION OF SYMBOLS 1 Display apparatus 10,210,310 Display panel 20 Drive control part 21,22,23,24 Drive circuit 25 Control circuit 101 Substrate 103 TFT substrate 107 Anode 109 Hole injection layer 111 Bank 113 Light emitting layer 115 Electron transport layer 117 Cathode 119 , 219 Sealing part 121 Buffer layer 123 Sealing layer 211 Sub buffer layer 213 Sub sealing layer

Claims (17)

A step of preparing a panel intermediate body laminated in the order of a first electrode, a light emitting functional layer and a second electrode comprising a conductive oxide;
Forming a buffer layer mainly composed of a first compound on the reduced second electrode by a reactive film-forming method in a state in which the reduction treatment is performed on the second electrode;
While performing the reduction processing on the buffer layer, and a step of forming by a reactive deposition method a sealing layer shall be the main component of the second compound on the buffer layer,
The method for manufacturing a display panel, wherein the first compound is an oxide of the second compound. The method for manufacturing a display panel according to claim 1, wherein the reduction treatment for the buffer layer reduces substantially all of the first compound in the buffer layer to the second compound. 2. The display panel according to claim 1, wherein the reduction process on the buffer layer reduces an area close to the sealing layer in a thickness direction of the buffer layer and does not reduce an area close to the second electrode. Manufacturing method. The method for manufacturing a display panel according to claim 1, wherein the reduction treatment for the buffer layer is performed by irradiating with NH 3 plasma. Further, a step of forming a sub-buffer layer containing a third compound as a main component on the sealing layer by a reactive film formation method;
Forming a sub-encapsulation layer containing a fourth compound as a main component on the sub-buffer layer in a state where the sub-buffer layer is subjected to a reduction treatment, by a reactive film formation method,
The method for manufacturing a display panel according to claim 1, wherein the third compound is an oxide of the second compound. The display panel manufacturing method according to claim 5, wherein the fourth compound contains an oxide as a main component. The second electrode is made of an ITO film,
The first compound is silicon oxynitride;
The method for manufacturing a display panel according to claim 1, wherein the second compound is silicon nitride. The method for manufacturing a display panel according to claim 5, wherein the reactive film forming method employed in the step of forming the sub sealing layer is an ALD method. A first electrode;
A light emitting functional layer formed on the first electrode;
A second electrode made of a conductive oxide and formed on the light emitting functional layer;
Together is formed on the second electrode, wherein not covering the surface of the second electrode, a buffer layer composed mainly of a first compound,
While being formed on the buffer layer, not covering the surface of the buffer layer, and a sealing layer composed mainly of a second compound,
The main component of the region located at least in the vicinity of the sealing layer in the thickness direction of the buffer layer and the main component of the sealing layer are the same compound,
A display panel, wherein a chemical bond is formed at an interface between the second electrode and the buffer layer and an interface between the buffer layer and the sealing layer. The display panel according to claim 9, wherein a main component of substantially all the region of the buffer layer and a main component of the sealing layer are the same compound. In the buffer layer, a layer mainly composed of an oxide of a main component of a region located in the vicinity region of the sealing layer is located between the region located in the vicinity of the sealing layer and the sealing layer. The display panel according to claim 9 . The second electrode is made of an ITO film,
The first compound is silicon oxynitride;
The display panel according to claim 9, wherein the second compound is silicon nitride. A sub-buffer layer formed on the sealing layer and covering a surface of the sealing layer;
A sub sealing layer formed on the sub buffer layer and covering a surface of the sub buffer layer;
The main component of the sub-buffer layer and the main component of the buffer layer are the same compound,
The chemical bond is formed in the interface of the said sealing layer and the said subbuffer layer, and the interface of the said subbuffer layer and the said subsealing layer, The any one of Claim 9 thru | or 12 characterized by the above-mentioned. The display panel described in 1. The display panel according to claim 9, wherein the second electrode has light transmittance. The display panel according to claim 13 , wherein the sub sealing layer contains an oxide as a main component. 11. The display panel according to claim 10, wherein in the thickness direction of the buffer layer, the ratio of one constituent element of the compound that is a main component of the buffer layer increases as the sealing layer is approached. . The ratio of one constituent element of the compound that is a main component of the sub-buffer layer increases in the thickness direction of the sub-buffer layer as it approaches the sub-sealing layer. Display panel.

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