JP7083103B2 - OLED display device and its manufacturing method - Google Patents

Description

The present disclosure relates to an OLED display device and a method for manufacturing the same.

Since the OLED (Organic Light-Emitting Diode) element is a current-driven self-luminous element, it does not require a backlight and has advantages such as low power consumption, high viewing angle, and high contrast ratio. It is expected in the development of flat panel displays.

A typical OLED display device includes a plurality of sub-pixels arranged in a matrix. Each sub-pixel includes an organic light emitting layer that emits either blue, red, or green, and an anode and a cathode that sandwich the organic light emitting layer. For example, Patent Documents 1 and 2 show a configuration example of an OLED display device.

U.S. Patent Application Publication No. 2013/02488667 Japanese Unexamined Patent Publication No. 2016-10395

In the OLED display device, the image quality deteriorates due to various causes, and it is desired to suppress the deterioration.

The OLED display device of one aspect of the present disclosure includes a plurality of sub-pixels arranged on a surface of a substrate, and a pixel definition layer surrounding a light emitting region of each of the plurality of sub-pixels. Each of the plurality of sub-pixels has an upper electrode, a lower electrode, an organic light emitting layer laminated with the upper electrode and the lower electrode between the upper electrode and the lower electrode, and the lower electrode and the organic. The lower electrode and the lower carrier supply layer laminated with the organic light emitting layer are included between the light emitting layer and the light emitting layer. The lower carrier supply layer comes into contact with each of the lower electrode and the organic light emitting layer, supplies carriers from the lower electrode to the organic light emitting layer, and covers the entire surface in the opening of the pixel definition layer of the lower electrode. It has an end on the top surface of the pixel definition layer surrounding the lower electrode. The organic light emitting layer covers the entire surface of the lower carrier supply layer including the end of the lower carrier supply layer.

According to one aspect of the present disclosure, deterioration of image quality due to crosstalk between sub-pixels can be suppressed.

In the first embodiment, a configuration example of the OLED display device is schematically shown. In the first embodiment, a plan view of a part of the display area is shown. FIG. 2A shows a cross-sectional view taken along the line IIB-IIB. In the first embodiment, the cross-sectional structure of the TFT substrate is schematically shown. FIG. 2B is an enlarged view of a portion surrounded by a circular broken line D in FIG. 2B. In the first embodiment, an example of a metal mask corresponding to the pattern of the red subpixel R is shown. FIG. 3A shows a cross-sectional view taken along the line IIIB-IIIB. FIG. 3A shows a cross-sectional view taken along the line IIIC-IIIC. In the first embodiment, a state in which organic materials of each color are vapor-deposited on the pixel definition layer is schematically shown. FIG. 4A shows a cross-sectional view taken along the IVB-IVB cutting line. FIG. 4A shows a cross-sectional view taken along the IVC-IVC cutting line. In the first embodiment, the flowchart of the manufacturing process after forming the pixel definition layer is shown. In the first embodiment, the relationship between the metal mask for the hole supply layer and the metal mask for the organic light emitting layer is schematically shown. In the first embodiment, the cross-sectional structure of the TFT substrate manufactured by using the metal mask for the hole supply layer and the metal mask for the organic light emitting layer having the relationship shown in FIG. 6 for the sub-pixels of each color is schematically shown. .. In the second embodiment, a plan view of a part of the display area is shown. In the second embodiment, the relationship between the hole supply layer of the blue subpixel and the blue organic light emitting layer is schematically shown. FIG. 8A shows a part of the cross-sectional structure at the VIIIC-VIIIC cutting line. In the second embodiment, a flowchart of the manufacturing method is shown. In the third embodiment, a configuration example of the metal mask used for forming the hole supply layer is schematically shown. A flowchart of a manufacturing method for forming a hole supply layer using the metal mask shown in FIG. 10 is shown. An example of the cross-sectional structure of the TFT substrate is schematically shown. An example of the cross-sectional structure of the TFT substrate is schematically shown. An example of the cross-sectional structure of the TFT substrate is schematically shown. An example of the cross-sectional structure of the TFT substrate is schematically shown. An example of the cross-sectional structure of the TFT substrate is schematically shown. In the fourth embodiment, a plan view of a part of the display area is shown. FIG. 17 shows a first cross-sectional view taken along the XVIII-XVIII cut line in FIG. FIG. 17 shows a second cross-sectional view taken along the XVIII-XVIII cut line in FIG. It is a figure explaining the metal mask used for forming the layer structure described in the cross-sectional view of FIG. It is a figure explaining the metal mask used for forming the layer structure described in the cross-sectional view of FIG. The flowchart of the manufacturing process after forming the pixel definition layer in Embodiment 4 is shown.

Hereinafter, the configuration of an OLED (Organic Light-Emitting Diode) and a method for manufacturing the same will be disclosed. The inventors of the OLED display device described in the present embodiment have shown that when only the blue sub-pixels are made to emit light in the OLED display panel, the red and green sub-pixels that should not be emitted are weakly emitted. I found that there was something to do. Unintended emission of sub-pixels causes a decrease in color purity of the displayed image, particularly a low gradation display abnormality. Therefore, it is desirable to prevent unintended emission of sub-pixels.

According to the research by the inventors, in the OLED display panel, when a carrier supply layer having carrier mobility is formed between the electrode and the organic light emitting layer in the subpixel, the unintended subpixel is formed over the entire display region. It turned out that luminescence occurs. The carrier supply layer is, for example, a hole supply layer including a hole injection layer and / or a hole transport layer.

When there is a difference in the applied voltage between the adjacent sub-pixels, a carrier leak occurs between the adjacent sub-pixels via the carrier supply layer. For example, when only the blue sub-pixels emit light, a minute current in the current applied to the blue sub-pixels flows through the carrier supply layer to the adjacent red and green sub-pixels that are not intended to emit light. The path through which this minute current flows is also called a leak path.

This minute current causes the red and green adjacent sub-pixels to emit light slightly (so-called crosstalk). This phenomenon is more remarkable as the distance between adjacent sub-pixels is shorter, and is particularly easily recognized in the case of low-tone display. Therefore, in the present embodiment, the structure of the OLED display device that reduces or eliminates the leak path in order to suppress this carrier leak will be described.

In the OLED display device disclosed below, the lower carrier supply layer that supplies carriers from the lower electrode to the organic light emitting layer covers the entire surface of the lower electrode within the opening of the pixel definition layer and surrounds the lower electrode on the top surface of the pixel definition layer. Has an end. The organic light emitting layer covers the entire surface of the lower carrier supply layer including the end of the lower carrier supply layer. This makes it possible to reduce or eliminate the leak path in the lower carrier supply layer between the adjacent sub-pixels and suppress the carrier leak between the adjacent sub-pixels of different colors.

Hereinafter, embodiments will be described with reference to the accompanying drawings. The embodiments are merely examples for realizing the present invention, and do not limit the technical scope of the present invention. The same reference numerals are given to the common configurations in each figure. In order to make the explanation easier to understand, the dimensions and shapes of the illustrated objects may be exaggerated.

<Embodiment 1>
[Device configuration]
FIG. 1 schematically shows a configuration example of the OLED display device 10 according to the present embodiment. The OLED display device 10 is a joint portion (glass) that joins a TFT (Thin Film Transistor) substrate 100 on which an OLED element is formed, a sealing substrate 200 that seals the OLED element, and a TFT substrate 100 and a sealing substrate 200. The frit seal portion) 300 is included. For example, nitrogen is sealed between the TFT substrate 100 and the sealing substrate 200, and is sealed by the joint portion 300.

A scanning driver 131, an emission driver 132, a protection circuit 133, and a driver IC 134 are arranged around a cathode electrode forming region 114 outside the display region 125 of the TFT substrate 100. These are connected to an external device via an FPC (Flexible Printed Circuit) 135.

The scanning driver 131 drives the scanning lines of the TFT substrate 100. The emission driver 132 drives the emission control line to control the light emission period of each sub-pixel. The driver IC 134 is mounted using, for example, an anisotropic conductive film (ACF).

The driver IC 134 supplies a power supply and a timing signal (control signal) to the scanning driver 131 and the emission driver 132, and further supplies a data voltage corresponding to the video data to the data line. That is, the driver IC 134 has a display control function.

The sealing substrate 200 is a transparent insulating substrate, for example, a glass substrate. A λ / 4 retardation plate and a polarizing plate are arranged on the light emitting surface (front surface) of the sealing substrate 200 to suppress reflection of light incident from the outside.

FIG. 2A shows a plan view of a part of the display area 125. FIG. 2A shows a plurality of sub-pixels arranged in a matrix. At least three sub-pixels are sub-pixels that emit different first to third colors. The first color is, for example, blue, the second color is, for example, red, and the third color is, for example, green. FIG. 2A shows a red sub-pixel (light emitting region) 251R, a blue sub pixel (light emitting region) 251B, and a green sub pixel (light emitting region) 251G. Of the sub-pixels in FIG. 2A, only one sub-pixel of each of red, blue, and green is indicated by a reference numeral. Each sub-pixel displays either red, blue, or green. One pixel (main pixel) is composed of red, blue, and green sub-pixels.

In the example of FIG. 2A, the red sub-pixel 251R, the blue sub-pixel 251B, and the green sub-pixel 251G are cyclically arranged in the row direction (horizontal direction in FIG. 2A). In the example of FIG. 2A, from left to right, the sub-pixels (light emitting regions) of different colors are arranged in the order of the red sub-pixel 251R, the blue sub-pixel 251B, and the green sub-pixel 251G. Sub-pixels of the same color are arranged in the column direction (vertical direction in FIG. 2A). The order of the red sub-pixel, the blue sub-pixel, and the green sub-pixel is arbitrary, and may be, for example, the order of the red pixel, the green sub-pixel, and the blue sub-pixel.

Each sub-pixel (light emitting region) is surrounded by an insulating pixel definition layer 253. The pixel definition layer 253 defines each of the sub-pixels (light emitting region). The sub-pixel (light emitting region) is formed in the opening of the pixel definition layer 253.

The entire area of each sub-pixel (light emitting area) is covered with an organic light emitting layer of the same color. Specifically, the red sub-pixel 251R, the blue sub-pixel 251B, and the green sub-pixel 251G are completely covered with the organic light emitting layer 269R, the blue organic light emitting layer 269B, and the green organic light emitting layer 269G, respectively. Of the organic light emitting layers in FIG. 2A, only one organic light emitting layer of each of red, blue, and green is designated by a reference numeral.

FIG. 2B shows a cross-sectional view taken along the IIB-IIB cutting line in FIG. 2A. The OLED display device 10 includes a TFT substrate 100 and a sealing substrate (transparent substrate) 200 facing the TFT substrate 100. FIG. 2B schematically shows the cross - sectional structure of the TFT substrate 100.

The OLED display device 10 includes a TFT circuit layer 263 arranged on an insulating substrate 261 and a plurality of separated lower electrodes (eg, anode electrodes 265B, 265G). The separated lower electrode is included in the lower electrode layer. The OLED display device 10 further includes an upper electrode (layer) (for example, a cathode electrode (layer) 273) and a plurality of organic light emitting layers 269B and 269G. The layer may be composed of one continuous portion formed at the same time or a plurality of separated portions. In the following, a part of the layer may also be referred to as a layer.

The insulating substrate 261 is made of, for example, glass or resin and is an inflexible or flexible substrate. The side closer to the insulating substrate 261 is referred to as a lower side, and the side farther from the insulating substrate 261 is referred to as an upper side. A cap layer (not shown) may be formed on the cathode electrode (upper electrode) 273.

The anode electrodes 265B and 265G are the anode electrodes of the blue subpixel 251B and the green subpixel 251G, respectively. The cathode electrode 273 is a transparent electrode that transmits a part or all of the visible light from the organic light emitting layer toward the sealing structure portion, and is common to all the sub-pixels.

An organic light emitting layer is arranged between the cathode electrode and one anode electrode. The plurality of anode electrodes are arranged on the surface of the TFT circuit layer 263 (for example, on a flattening film), and one organic light emitting layer is arranged on one anode electrode.

Each TFT circuit layer 263 has a plurality of sub-pixel circuits (hereinafter, simply referred to as pixel circuits) including a plurality of TFTs. Each of the pixel circuits is formed between the insulating substrate 261 and the anode electrode, and controls the current supplied to each of the anode electrodes. The anode electrode is connected to the pixel circuit by a contact portion formed in the contact hole of the flattening film.

A pixel circuit having an arbitrary configuration can be used. An example of a pixel circuit includes, for example, a switch TFT for selecting a sub-pixel, a TFT for driving an OLED element, a switch TFT for controlling supply and stop of a drive current to the OLED element, and a holding capacity.

In FIG. 2B, the organic light emitting layer 269B is arranged between the cathode electrode 273 and the anode electrode 265B. An organic light emitting layer 269G is arranged between the cathode electrode 273 and the anode electrode 265G. In the example of FIG. 2B, organic light emitting layers of different colors are formed.

A hole supply layer is laminated between the anode electrode and the organic light emitting layer. The hole supply layer is in contact with each of the anode electrode and the organic light emitting layer to form an interface. The hole supply layer is composed of, for example, a hole injection layer and a hole transport layer, or is composed of one or more layers having the functions of these layers. The hole supply layer is also referred to as a lower carrier supply layer. In FIG. 2B, the hole supply layer of each sub-pixel is formed separately from the hole supply layer of adjacent sub-pixels of different colors.

For example, the hole supply layer 267B is arranged between the anode electrode 265B and the organic light emitting layer 269B, and the hole supply layer 267G is arranged between the anode electrode 265G and the organic light emitting layer 269G. The hole supply layers 267B and 267G are separated.

An electron supply layer is arranged between the cathode electrode and the organic light emitting layer. The electron supply layer is in contact with each of the cathode electrode and the organic light emitting layer to form an interface. In FIG. 2B, the electron supply layer 271 of each sub-pixel is a part of the layer common to the sub-pixels. The electron supply layer 271 is arranged between the cathode electrode 273 and the organic light emitting layer 269B and between the cathode electrode 273 and the organic light emitting layer 269G. The electron supply layer 271 is composed of, for example, an electron injection layer and an electron transport layer, or is composed of one or more layers having the functions of these layers. The electron supply layer 271 is also referred to as an upper carrier supply layer.

One OLED element is configured to include an anode electrode which is a lower electrode, a hole supply layer, an organic light emitting layer, an electron supply layer, and a cathode electrode which is an upper electrode in the opening of the pixel definition layer 253.

The pixel definition layer is a layer between the anode electrode and the hole supply layer. In FIG. 2B, the pixel definition layer 253 is formed between the anode electrodes 265B and 265G and the hole supply layer 267B and 267G. The pixel definition layer 253 includes a side surface in the opening in which the sub-pixels are formed and a top surface between the openings. In the example of FIG. 2B, the top surface is flat.

As shown in FIG. 2B, the hole supply layer 267B is formed on the anode electrode 265B and the pixel definition layer 253 in contact with them. Similarly, the hole supply layer 267G is formed on the anode electrode 265G and the pixel definition layer 253 in contact with them.

FIG. 2C schematically shows the positional relationship between the sub-pixel (opening of the pixel definition layer), the hole supply layer, and the organic light emitting layer. As shown in FIGS. 2B and 2C, the hole supply layer 267B is formed so as to cover a part of the top surface of the pixel definition layer 253 surrounding the hole supply layer 267B. That is, the hole supply layer 267B is formed only on a part of the top surface, and the end of the hole supply layer 267B exists on the top surface of the pixel definition layer 253.

Similarly, the hole supply layer 267G is formed so as to cover a part of the top surface of the pixel definition layer 253 that surrounds the hole supply layer 267G. That is, the hole supply layer 267G is formed only on a part of the top surface, and the end of the hole supply layer 267G exists on the top surface of the pixel definition layer 253.

The hole supply layer 267B and the hole supply layer 267G are separated from each other in the in-plane direction (direction in the main surface of the insulating substrate 261), and a gap exists between them. Specifically, on the pixel definition layer 253, the end of the hole supply layer 267B is separated from the end of the hole supply layer 267G, and a gap G exists between them. In this example, the hole supply layer of each sub-pixel is separated from the hole supply layer of adjacent sub-pixels of different colors. In this example, the hole supply layer of each sub-pixel is separated from the hole supply layer of all the adjacent sub-pixels, but the hole supply layers of the adjacent sub-pixels of the same color may be continuous.

The hole supply layer of each subpixel has an appropriate thickness for the microcavity structure. In FIG. 2B, the hole supply layer 267G for the green subpixel is thicker than the hole supply layer 267B for the blue subpixel.

The organic light emitting layer 269B is laminated directly above the hole supply layer 267B, that is, on the hole supply layer 267B so as to contact the hole supply layer 267B and form an interface. Similarly, an organic light emitting layer 269G is laminated directly above the hole supply layer 267G, that is, on the hole supply layer 267G so as to contact the hole supply layer 267G and form an interface. The organic light emitting layer 269B covers the entire surface including the entire outer peripheral end of the hole supply layer 267B. Similarly, the organic light emitting layer 269 G covers the entire surface including the entire outer peripheral edge of the hole supply layer 267 G.

FIG. 2D is an enlarged view of a portion surrounded by a circular broken line D in FIG. 2B. The plane position of the circular broken line D is indicated by reference numeral D in FIG. 2C. FIG. 2D shows the ends of the hole supply layer 267B and the organic light emitting layer 269B. FIG. 2D shows the pixel definition layer 253, the hole supply layer 267B on the pixel definition layer 253, and the organic light emitting layer 269B on the hole supply layer 267B. The organic light emitting layer 269B completely covers the hole supply layer 267B, and the hole supply layer 267B is not exposed at all from the organic light emitting layer 269B. The outer peripheral edge of the organic light emitting layer 269B exists on the top surface of the pixel definition layer 253 and surrounds the outer peripheral edge of the hole supply layer 267B.

As shown in FIGS. 2B and 2C, it is preferable that the organic light emitting layer 269G completely covers the hole supply layer 267G, and the hole supply layer 267G is not exposed at all from the organic light emitting layer 269G. The outer peripheral edge of the organic light emitting layer 269G exists on the top surface of the pixel definition layer 253 and surrounds the outer peripheral edge of the hole supply layer 267G.

In FIGS. 2B and 2C, the end of the organic light emitting layer exists between the end of the hole supply layer covered by the organic light emitting layer and the end of the hole supply layer of adjacent subpixels of different colors. For example, the end of the blue organic light emitting layer 269B exists between the end of the hole supply layer 267B of the blue subpixel and the hole supply layer 267G of the green subpixel. Similarly, the end of the green organic light emitting layer 269G exists between the end of the hole supply layer 267G of the green subpixel and the hole supply layer 267B of the blue subpixel.

Substantial leak paths for carrier leaks between sub-pixels of different colors are formed in the hole supply layer. Since the hole supply layers of the sub-pixels of different colors are separated from each other, carrier leakage between the sub-pixels of different colors can be reduced. Further, the hole supply layers of the sub-pixels of different colors are separated, and the electron supply layer is formed in the separated places, but the organic light emitting layer is between the sub-pixels of different colors. It covers the entire surface of the hole supply layer including the edge of the hole supply layer.

That is, the hole supply layers of the sub-pixels of different colors do not come into direct contact with the electron supply layer. Even if the carrier mobility of the hole supply layer and the organic light emitting layer are similar, holes easily move from the hole supply layer to the organic light emitting layer, but since the energy barrier to holes is large, the organic light emitting layer It hardly moves to the hole supply layer. Therefore, the hole supply layer of the sub-pixel of the first color passes through the organic light emitting layer of the sub pixel of the first color, the electron supply layer, and the organic light emitting layer of the sub pixel of the second color, and the sub of the second color. The formation of a leak path leading to the hole supply layer of the pixel is suppressed. Therefore, it is possible to more effectively prevent carrier leakage between sub-pixels of different colors.

As shown in FIG. 2A, in this example, the organic light emitting layer of each sub- pixel is separated from the organic light emitting layer of the adjacent sub-pixel. For example, in FIG. 2B, the ends of the blue organic light emitting layer 269B are separated from the ends of the green organic light emitting layer 269G in the in-plane direction, and there is a gap between them.

The electron supply layer 271 is present on the organic light emitting layer 269B and 269G in contact with the organic light emitting layer 269B and 269G. The electron supply layer 271 is a layer common to all sub-pixels. In the example of FIG. 2B, the electron supply layer 271 is continuous between the two sub-pixels 251G and 251B without being cut off on the pixel definition layer 253. The electron supply layer 271 may be formed for each color of the sub-pixel.

The cathode electrode 273 is present on the electron supply layer 271 in contact with the electron supply layer 271. The cathode electrode 273 is a layer common to all sub-pixels. In the example of FIG. 2B, the cathode electrode 273 is continuous between the two sub-pixels 251G and 251B without being cut on the pixel definition layer 253.

2B, 2C and 2D show the structure between and in the vicinity of the blue sub-pixel 251B and the green sub-pixel 251G. The above description with reference to FIGS. 2B, 2C and 2D describes the hole supply layer 267R and the organic light emitting layer 269R of the red subpixel, and between the red subpixel 251R and the subpixels 251B and 251G of other colors. Applies to relationships.

Before explaining an example of the manufacturing method of the OLED display device 10 in the present embodiment, refer to FIGS. 3A to 3C and FIGS. 4A to 4C to supply holes using a metal mask in the present embodiment. The vapor deposition of organic materials such as layers will be briefly described. The description of this vapor deposition is the same as long as it is an organic material, for example, a light emitting material.

FIG. 3A shows an example of the metal mask 400R corresponding to the pattern of the red subpixel R. The metal mask 400R has an opening 401R laid out corresponding to the pattern of the red subpixel R. The X direction indicates the left-right direction of the paper surface, and the Y direction indicates the vertical direction of the paper surface.

FIG. 3B shows a cross-sectional view taken along the line IIIB-IIIB in FIG. 3A. FIG. 3C shows a cross-sectional view taken along the IIIC-IIIC cutting line in FIG. 3A. The substrate 101A of FIG. 3B schematically shows the substrate 261 on which the pixel definition layer 253 is formed. The metal mask 400R is arranged (aligned) so that the organic material of the red subpixel R is vapor-deposited at a predetermined position on the substrate 101A.

The thin-film deposition source 500 shown in FIGS. 3B and 3C accommodates an organic material to be vapor-deposited inside. The vapor deposition source 500 accommodates, for example, the organic material of the red subpixel R. The organic material contained in the vapor deposition source 500 is heated, and the heated organic material is vaporized. The vaporized organic material is ejected to the outside from the ejection port of a nozzle (not shown). The ejected organic material passes through the opening 401R of the metal mask 400R and is vapor-deposited at a predetermined position on the substrate 101A to form a film.

The shape of the vapor deposition source 500 is, for example, a rectangular shape. As shown in FIG. 3B, the longitudinal direction of the vapor deposition source 500 is along the X direction of FIG. 3A. Further, as shown in FIG. 3C, the lateral direction of the vapor deposition source 500 is along the Y direction of FIG. 3A. The vapor deposition source 500 moves along the Y direction of FIG. 3A. This movement is indicated by an arrow in the left-right direction of the paper in FIG. 3C.

As shown in FIG. 3B, the vapor deposition source 500 ejects the organic material in one direction in the X direction of FIG. 3A. This ejection state is indicated by the dotted arrow in FIG. 3B. Further, as shown in FIG. 3C, the vapor deposition source 500 ejects the organic material in a plurality of directions in the Y direction. This ejection state is indicated by the dotted arrow in FIG. 3C.

Due to the moving direction of the vapor deposition source 500 and the ejection state, the shape of the taper of the organic material in the X direction and the shape of the taper of the organic material in the Y direction are different after the film formation of the organic material.

FIG. 4A schematically shows a state in which an organic material of each color is vapor-deposited on the pixel definition layer 253. The organic layers 402R and 402Ra of the red pixel schematically show the hole supply layer and the organic light emitting layer of the red pixel described with reference to FIG. 2, respectively. The organic layer 402B of the blue pixel schematically shows the hole supply layer and the organic light emitting layer of the blue pixel. The organic layer 402G of the green pixel schematically shows the hole supply layer and the organic light emitting layer of the green pixel. The organic layer 402B of the blue pixel and the organic layer 402G of the green pixel are each deposited by a metal mask having an aperture pattern different from the aperture pattern in the metal mask 400R for the red subpixel described with reference to FIG. 3A.

FIG. 4B is a cross-sectional view taken along the IVB-IVB cutting line in FIG. 4A, showing the tapered shapes of the organic layers 402R and 402B in the X direction, which is the direction in which the vapor deposition source 500 does not move. FIG. 4C is a cross-sectional view taken along the IVC - IVC cutting line in FIG. 4A, showing the tapered shapes of the organic layers 402R and 402Ra in the Y direction, which is the direction in which the vapor deposition source 500 moves.

As shown in FIGS. 4B and 4C, the taper in the X direction is steeper than the taper in the Y direction. More specifically, the angle of the inclined surface 402Rx of the organic layer 402R in FIG. 4B (the angle with respect to the flat surface portion of the pixel definition layer 253) is larger than the angle of the inclined surface 402Ry (see FIG. 4C) of the same organic layer 402R.

Even in the case of other pixels, for example, the organic layer 402B of blue pixels and the organic layer 402Ra of red pixels, the taper in the X direction is steeper than the taper in the Y direction. The reason for this is that the vapor deposition source 500 moves in the Y direction, and the ejection directions of the organic material are a plurality of directions in the Y direction, so that the amount of the organic material deposited in the X direction per unit time is in the Y direction. This is because it tends to be larger than the amount of organic material to be laminated. As described above, since the taper of the organic layer is steep in the X direction in which the sub-pixels of different colors are arranged, it is possible to suppress the sub-pixels of different colors from coming into contact with each other.

Although the case where the vapor deposition source moves in one direction (for example, the Y direction) is illustrated in FIGS. 3A to 4C, the vapor deposition source or the substrate 101A is rotated to deposit an organic material on the substrate 101A to form a film, so-called rotation. There is also a film forming method. In the case of this rotary film forming method, the shape of the taper of the sub-pixel differs depending on the position of the sub-pixel in the display panel.

The phenomenon that the taper shape of the organic layer differs in each direction even with the same pixel is different from the case where the organic material is deposited by sputtering or CVD (chemical vapor deposition), and the organic material is vapor-deposited using a metal mask. It is a peculiar phenomenon that occurs in.

[Production method]
An example of the manufacturing method of the OLED display device 10 will be described. In the following description, the elements formed (simultaneously) in the same process are the elements of the same layer. In the manufacture of the OLED display device 10, first, the TFT circuit layer 263 is formed on the insulating substrate 261. Known techniques can be used to form the TFT circuit layer 263, and detailed description thereof will be omitted. Next, an anode electrode is formed on the TFT circuit layer 263. For example, sputtering is used to form an anode electrode on a flattening film with contact holes.

The anode electrode is composed of an upper ITO / Ag alloy / a lower ITO. A transparent film such as ITO, IZO, ZnO, In ₂ O ₃ instead of the upper ITO, Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr or a compound metal thereof instead of the upper ITO. The above-mentioned transparent film may be used instead of the reflective film and the lower ITO. The layer structure of the anode electrode is arbitrary, and for example, Al may be one layer. The anode electrode is connected to the pixel circuit in the TFT circuit layer 263 via the contact portion.

Next, for example, a photosensitive organic resin film is deposited by a spin coating method or the like, and patterning is performed to form the pixel definition layer 253. An opening is formed in the pixel definition layer 253 by patterning, and the anode electrode of each sub-pixel is exposed at the formed opening. Sub-pixels (light emitting regions) are separated by the pixel definition layer 253.

The manufacturing process after forming the pixel definition layer 253 will be described with reference to the flowchart of FIG. A hole supply layer for red sub-pixels is formed on the insulating substrate 261 on which the pixel definition layer 253 is formed (S101). Specifically, the material of the hole supply layer is adhered to the substrate 261 on which the pixel definition layer 253 is formed by vapor deposition via a metal mask corresponding to the pattern of the red sub-pixels, and the holes of the red sub-pixels are supplied. A layer is formed. When the hole supply layer is composed of a plurality of layers including a hole injection layer and a hole transport layer, the plurality of layers are repeatedly formed. The thickness of the hole supply layer may be controlled due to the microcavity structure.

Next, the hole supply layer of the green sub-pixel is formed on the insulating substrate 261 on which the pixel definition layer 253 is formed (S102). Specifically, the material of the hole supply layer is adhered to the substrate 261 on which the pixel definition layer 253 is formed by vapor deposition via a metal mask corresponding to the pattern of the green subpixel, and the holes of the green subpixel are supplied. A layer is formed. When the hole supply layer is composed of a plurality of layers, the plurality of layers are repeatedly formed. The thickness of the hole supply layer may be controlled due to the microcavity structure.

Next, the hole supply layer of the blue sub-pixel is formed on the insulating substrate 261 on which the pixel definition layer 253 is formed (S103). Specifically, the material of the hole supply layer is adhered to the substrate 261 on which the pixel definition layer 253 is formed by vapor deposition via a metal mask corresponding to the pattern of the blue sub-pixels, and the holes of the blue sub-pixels are supplied. A layer is formed. When the hole supply layer is composed of a plurality of layers, the plurality of layers are repeatedly formed. The thickness of the hole supply layer may be controlled due to the microcavity structure.

As shown in FIGS. 2B and 2C, in the manufacturing step of this example, in the film formation of the hole supply layer of the sub-pixels of each color, the area wider than the opening formed in the pixel definition layer 253 (also referred to as the vapor deposition coating margin). A hole supply layer is deposited on the hole supply layer. This takes into consideration the pattern accuracy of the metal mask, the deformation of the metal mask due to heat during film formation, the alignment accuracy between the metal mask and the substrate, the incident angle of the vapor-deposited molecules, and the like. The steps S101, S102 and S103 are in no particular order.

Next, an organic light emitting material is adhered on the hole supply layer to form an organic light emitting layer. An organic light emitting material is formed for each of the red, green, and blue colors to form an organic light emitting layer on the hole supply layer. A metal mask is used to form the organic light emitting layer.

First, an organic light emitting layer of red subpixels is formed (S104). Specifically, the material of the red organic light emitting layer is adhered on the hole supply layer of the red subpixel by vapor deposition via a metal mask corresponding to the pattern of the red subpixel to form a red organic light emitting layer. do.

Next, the organic light emitting layer of the green subpixel is formed (S105). Specifically, the material of the green organic light emitting layer is adhered to the hole supply layer of the green subpixel by vapor deposition via a metal mask corresponding to the pattern of the green subpixel to form a green organic light emitting layer. do.

Next, the organic light emitting layer of the blue subpixel is formed (S106). Specifically, the material of the blue organic light emitting layer is adhered to the hole supply layer of the blue sub pixel by vapor deposition via a metal mask corresponding to the pattern of the blue sub pixel to form a blue organic light emitting layer. do.

In the film formation of the organic light emitting layer of the sub-pixels of each color, the organic light emitting layer is deposited in an area wider than the opening formed in the pixel definition layer 253, similarly to the hole supply layer. Further, the organic light emitting layer of each sub-pixel is formed so as to cover the entire surface of the hole transport layer of the sub-pixel. The steps S104, S105 and S106 are in no particular order.

Next, the material of the electron supply layer 271 is adhered to the organic light emitting layer to form the electron supply layer 271 common to all the sub-pixels (S107). The electron supply layer 271 is formed over the entire display region 125. The electron supply layer 271 forms a film on all the sub-pixels at the same time.

Next, a metal material for the cathode electrode 273 is attached onto the electron supply layer 271 (S108). The cathode electrode 273 forms a film over the entire display region 125. The cathode electrode 273 forms a film on all the sub-pixels at the same time. The cathode electrode 273 is formed by, for example, depositing Li, Ca, LiF / Ca, LiF / Al, Al, Mg or an alloy thereof. After forming the cathode electrode 273, an insulating film having a higher refractive index than glass may be deposited to form a cap layer in order to improve the light extraction efficiency.

Next, a glass frit is applied to the outer periphery of the TFT substrate 100, a sealed substrate 200 is placed on the glass frit, and the glass frit portion is heated by a laser beam to melt the TFT substrate 100 and the sealed substrate 200. do.

As described above, in the present embodiment, the organic light emitting layer of the sub-pixels of each color is formed so as to cover the entire surface of the hole supply layer. The hole supply layer and the organic light emitting layer can be formed by thin film deposition using different metal masks. FIG. 6 schematically shows the relationship between the metal mask 43 for the hole supply layer of the same color sub-pixels and the metal mask 45 for the organic light emitting layer.

The metal mask 43 for the hole supply layer has an opening 432 laid out according to the corresponding subpixel pattern. The metal mask 45 for the organic light emitting layer has an opening 452 laid out according to the pattern of the corresponding sub-pixels. In FIG. 6, only one of the plurality of openings for the hole supply layer is designated by reference numeral 432, and only one of the plurality of openings for the organic light emitting layer is designated by reference numeral 452.

As shown in FIG. 6, the opening 452 for the organic light emitting layer is larger than the opening 432 for the hole supply layer. The opening 452 for the organic light emitting layer has a shape and size that can accommodate the opening 432 for the hole supply layer. Due to this relationship, the entire surface of the hole supply layer can be more reliably covered with the organic light emitting layer. For each of the red sub-pixel, the blue sub-pixel, and the green sub-pixel, a metal mask 43 for the hole supply layer and a metal mask 45 for the organic light emitting layer having the above relationship are prepared.

FIG. 7 schematically shows a cross-sectional structure of a TFT substrate 100 manufactured by using a metal mask for a hole supply layer and a metal mask for an organic light emitting layer having the above relationship for sub-pixels of each color.
Compared with the configuration example shown in FIG. 2B, the outer portion (margin) of the organic light emitting layer 269B of the blue subpixel is larger than the hole supply layer 267B of the blue subpixel. Similarly, the outer portion (margin) of the organic light emitting layer 269G of the green sub-pixel to the hole supply layer 267G of the green sub-pixel is large.

<Embodiment 2>
Hereinafter, the configuration of the display area and the manufacturing method of the second embodiment will be described. Differences from the first embodiment will be mainly described.

[Display area configuration]
FIG. 8A shows a plan view of a part of the display area 125. FIG. 8A shows a plurality of sub-pixels arranged in a matrix. FIG. 8A shows a red sub-pixel (light emitting region) 251R, a blue sub pixel (light emitting region) 251B, and a green sub pixel (light emitting region) 251G. Of the sub-pixels in FIG. 8A, only one sub-pixel of each of red, blue, and green is indicated by a reference numeral.

The layout of the sub-pixels shown in FIG. 8A is the same as the layout shown in FIG. 2A in the first embodiment. In this configuration example, the distance between the sub-pixels is short for high definition. The organic light emitting layers of the sub-pixels of the same color are continuous. Specifically, the red organic light emitting layer 269R, the blue organic light emitting layer 269B, and the green organic light emitting layer 269G are not cut between the sub-pixels of the same color, and are continuous.

Although not shown in FIG. 8A, the same applies to the hole supply layer. That is, the hole supply layer of the red sub-pixel, the hole supply layer of the blue sub-pixel, and the hole supply layer of the green sub-pixel are not cut between the sub-pixels of the same color and are continuous.

Further, adjacent organic light emitting layers of different colors are partially overlapped on the top surface of the pixel definition layer 253. In the example of FIG. 8A, the end of the red organic light emitting layer 269R is laminated on the end of the blue organic light emitting layer 269B, and the other end of the red organic light emitting layer 269R is on the end of the green organic light emitting layer 269G. It is laminated in. Further, the end portion of the green organic light emitting layer 269G is laminated on the end portion of the blue organic light emitting layer 269B.

FIG. 8B schematically shows the relationship between the hole supply layer 267B of the blue subpixel and the blue organic light emitting layer 269B. In this example, the hole supply layer 267B is continuous in the arrangement direction of the blue subpixels 251B. The hole supply layer 267B has one end between the blue sub-pixel 251B and the green sub-pixel 251G, and the other end between the blue sub-pixel 251B and the red sub-pixel 251R. The organic light emitting layer 269B is laminated on the hole supply layer 267B so as to cover the entire surface of the hole supply layer 267B including both ends of the hole supply layer 267B.

FIG. 8C shows a portion of the cross-sectional structure at the VIIIC-VIIIC cutting line in FIG. 8A. FIG. 8C schematically shows the stacking relationship of the two hole supply layers 267B and 267G and the two organic light emitting layers 269B and 269G between the blue subpixel 251B and the green subpixel 251G.

Similar to the first embodiment, the hole supply layer 267B of the blue subpixel is formed so as to cover a part of the top surface of the pixel definition layer 253 surrounding the hole supply layer 267B. That is, the hole supply layer 267B is formed only on a part of the top surface, and the end of the hole supply layer 267B exists on the top surface of the pixel definition layer 253. The blue organic light emitting layer 269B is laminated directly above the hole supply layer 267B, that is, on the hole supply layer 267B so as to contact the hole supply layer 267B and form an interface. The blue organic light emitting layer 269B covers the entire surface including both ends (all ends) of the hole supply layer 267B.

The hole supply layer 267G of the green sub-pixel is formed so as to cover a part of the top surface of the pixel definition layer 253 surrounding the hole supply layer 267G. That is, the hole supply layer 267 G is formed only on a part of the top surface, and the end of the hole supply layer 267 G exists on the top surface of the pixel definition layer 253.

Further, a part of the hole supply layer 267G of the green subpixel overlaps with a part of the hole supply layer 267B and the organic light emitting layer 269B of the blue subpixel on the top surface of the pixel definition layer 253. Specifically, the end portion of the hole supply layer 267G of the green subpixel is laminated directly above the end portion of the blue organic light emitting layer 269B. The end of the hole supply layer 267G of the green subpixel constitutes a laminated structure together with the end of the hole supply layer 267B of the blue subpixel and the end of the blue organic light emitting layer 269B.

The end of the hole supply layer 267G of the green subpixel is between the end of the hole supply layer 267B and the end of the blue organic light emitting layer 269B of the blue subpixel and the blue subpixel 251B. The end of the hole supply layer 267B of the blue subpixel and the end of the blue organic light emitting layer 269B are between the end of the hole supply layer 267G of the green subpixel and the green subpixel 251G.

The end of the blue organic light emitting layer 269B exists between the end of the hole supply layer 267B of the blue subpixel and the end of the hole supply layer 267G of the green subpixel. The end of the blue organic light emitting layer 269B completely covers the end of the hole supply layer 267B of the blue subpixel, and the hole supply layer 267G of the green subpixel becomes the hole supply layer 267B of the blue subpixel. Separated without contact.

As described above, in the configuration in which the hole supply layers of the adjacent sub-pixels partially overlap with each other as the definition becomes higher, the organic light emitting layer exists between the hole supply layers in which the adjacent sub-pixels are stacked. The organic light emitting layer covers the entire region including the end of the lower hole supply layer among the laminated hole supply layers, and separates the lower hole supply layer from the upper hole supply layer. ing. Organic light emitting layers with low carrier mobility exist between hole supply layers of different colors, blocking leak paths between hole supply layers.

Further, as described with reference to FIG. 2, holes easily move from the hole supply layer to the organic light emitting layer even if the carrier mobility of the hole supply layer and the organic light emitting layer are about the same, but the holes are relative to the holes. Since the energy barrier is large, it hardly moves from the organic light emitting layer to the hole supply layer, so that the leak path between the laminated hole supply layers is blocked. As a result, leakage current between the hole supply layers can be prevented.

A green organic light emitting layer 269G is laminated directly above the hole supply layer 267G of the green subpixel, that is, on the hole supply layer 267G so as to contact the hole supply layer 267G and form an interface. The green organic light emitting layer 269G covers the entire surface including both ends (all ends) of the hole supply layer 267G.

In this example, the hole supply layer 267G is continuous in the arrangement direction of the green subpixel 251G. The hole supply layer 267B has one end between the blue sub-pixel 251B and the green sub-pixel 251G, and the other end between the blue sub-pixel 251B and the red sub-pixel 251R. The organic light emitting layer 269B is laminated on the hole supply layer 267B so as to cover the entire surface of the hole supply layer 267B including both ends of the hole supply layer 267B.

The description with reference to FIGS. 8B and 8C applies to the hole supply layer 267R and the organic light emitting layer 269R of the red subpixel, and the relationship between the red subpixel 251R and the subpixels 251B and 251G of other colors. To. In the above example, the hole supply layer 267R of the red subpixel is an upper layer of the green and blue organic light emitting layers 269G and 269B.

[Production method]
Hereinafter, a method of manufacturing the OLED display device 1 having the above configuration of the present embodiment will be described. FIG. 9 shows a flowchart of the manufacturing method of the present embodiment. A hole supply layer for blue sub-pixels is formed on the insulating substrate 261 on which the pixel definition layer 253 is formed (S131). Specifically, the material of the hole supply layer is adhered to the substrate on which the pixel definition layer 253 is formed by vapor deposition via a metal mask corresponding to the pattern of the blue subpixel, and the hole supply layer of the blue subpixel is attached. To form a film.

Next, a blue organic light emitting layer is formed (S132). Specifically, the material of the blue organic light emitting layer is adhered to the hole supply layer of the blue sub pixel by vapor deposition via a metal mask corresponding to the pattern of the blue sub pixel to form a blue organic light emitting layer. do. As described above, the blue organic light emitting layer is laminated on the hole supply layer of the blue subpixel so as to cover the entire surface including the end of the hole supply layer of the blue subpixel.

The metal mask of the hole supply layer of the blue subpixel and the metal mask of the blue organic light emitting layer may be common or different. When a common metal mask is used, the film formation regions of the hole supply layer and the organic light emitting layer can be controlled by controlling the angle of incidence of the material with respect to the metal mask.

Next, a hole supply layer of green sub-pixels is formed on the insulating substrate 261 on which the blue organic light emitting layer is formed (S133). Specifically, the material of the hole supply layer is adhered on the pixel definition layer 253 by vapor deposition via a metal mask corresponding to the pattern of the green sub-pixel to form a hole supply layer of the green sub-pixel. ..

Next, a green organic light emitting layer is formed (S134). Specifically, the material of the green organic light emitting layer is adhered to the hole supply layer of the green subpixel by vapor deposition via a metal mask corresponding to the pattern of the green subpixel to form a green organic light emitting layer. do. As described above, the green organic light emitting layer is laminated on the hole supply layer of the green subpixel so as to cover the entire surface including the end of the hole supply layer of the green subpixel. The metal mask of the hole supply layer of the green subpixel and the metal mask of the green organic light emitting layer may be common or different.

Next, the hole supply layer of the red sub-pixels is formed on the insulating substrate 261 on which the red organic light emitting layer is formed (S135). Specifically, the material of the hole supply layer is adhered on the pixel definition layer 253 by vapor deposition via a metal mask corresponding to the pattern of the red sub-pixels to form a hole supply layer of the red sub-pixels. ..

Next, a red organic light emitting layer is formed (S136). Specifically, the material of the red organic light emitting layer is adhered on the hole supply layer of the red subpixel by vapor deposition via a metal mask corresponding to the pattern of the red subpixel to form a red organic light emitting layer. do. As described above, the red organic light emitting layer is laminated on the hole supply layer of the red subpixel so as to cover the entire surface including the end of the hole supply layer of the red subpixel. The metal mask of the hole supply layer of the red subpixel and the metal mask of the red organic light emitting layer may be common or different.

As described above, pairs of hole supply layers and organic light emitting layers of sub-pixels of different colors are sequentially formed. The order of formation of pairs of sub-pixels of different colors is arbitrary. As described above, in the manufacturing method of the present embodiment, the sub-pixels of the same color are formed immediately after forming the hole supply layer of the sub-pixels of one color and before forming the hole supply layer of another color. Form an organic light emitting layer. As a result, in a configuration in which the ends of the hole supply layers of the sub-pixels of different colors overlap each other, an organic light emitting layer having a smaller carrier mobility than the hole supply layer can be formed between them. Leakage current between hole supply layers can be effectively prevented.

Next, the material of the electron supply layer 271 is adhered to form a film formation of the electron supply layer 271 common to all the sub-pixels (S137). The electron supply layer 271 is formed over the entire display region 125. Next, a metal material for the cathode electrode 273 is attached onto the electron supply layer 271 (S138). The formation of the electron supply layer 271 and the cathode electrode 273 is the same as in the first embodiment. The manufacturing method of the present embodiment can also manufacture the OLED display device 1 having the configuration described in the first embodiment.

<Embodiment 3>
Hereinafter, the manufacturing method of the third embodiment will be described. Differences from other embodiments will be mainly described. In this embodiment, the hole supply layers of the sub-pixels of all colors are formed at the same time. FIG. 10 schematically shows a configuration example of the metal mask 41 used for forming the hole supply layer. The metal mask 41 has an opening 412R for the hole supply layer of the red subpixel, an opening 412B for the hole supply layer of the blue subpixel, and an opening 412G for the hole supply layer of the green subpixel. .. FIG. 10 is coded in only one opening of each color. The aperture pattern matches the pattern of the sub-pixels.

FIG. 11 shows a flowchart of a manufacturing method for forming a hole supply layer using the metal mask 41 shown in FIG. The hole supply layers of all the sub-pixels are formed on the insulating substrate 261 on which the pixel definition layer 253 is formed (S151). Specifically, the material of the hole supply layer is adhered to the substrate 261 on which the pixel definition layer 253 is formed by vapor deposition via a metal mask 41 having an opening pattern for all the sub-pixels shown in FIG. , The hole supply layer of all the sub-pixels is formed. By using the common metal mask 41, the hole supply layer can be efficiently formed.

Next, the organic light emitting layer of the blue subpixel, the organic light emitting layer of the green subpixel, and the organic light emitting layer of the red subpixel are sequentially formed on the hole supply layer by thin-film deposition using different metal masks (these are: S152, S153, and S154). As in the other embodiments, the organic light emitting layer of the sub-pixels of each color is formed so as to cover the entire surface of the corresponding hole supply layer. The order of film formation of the three-color organic light emitting layers is arbitrary.

Next, the material of the electron supply layer is adhered to form an electron supply layer common to all the sub-pixels (S155). The electron supply layer is formed over the entire display area 125. Next, the electron supply layer of the red subpixel (only) is formed by, for example, thin-film deposition using a metal mask (S156). Next, the electron supply layer of the green sub-pixel (only) is formed by, for example, thin-film deposition using a metal mask (S157).

By selectively adding the electron supply layer of the red sub-pixel and the green sub-pixel, the thickness of the electron supply layer of the sub-pixel of each color can be controlled due to the microcavity structure. The order of forming the electron supply layer of the red subpixel and the formation of the electron supply layer of the green subpixel is arbitrary. After forming a common electron supply layer for all sub-pixels, a common electron supply layer is formed for the red sub-pixel and the green sub-pixel (excluding the blue sub-pixel), and then the electron supply layer for the red sub-pixel (only) is formed. May be formed. If the microcavity structure is not required, only the electron supply layer common to all the sub-pixels may be formed.

Next, a metal material for the cathode electrode is attached onto the electron supply layer (S158). The formation of the cathode electrode is the same as in the first embodiment.

Various cross-sectional structures of the OLED device will be described with reference to FIGS. 12 to 16. A pixel circuit for driving the OLED device of the sub-pixel is formed in the lower layer of the anode electrode of the sub-pixel, but the pixel circuit is not shown. FIG. 12 schematically shows an example of the cross-sectional structure of the TFT substrate 100. A hole injection layer 266R and a hole transport layer 268R are formed on the anode electrode 265R of the red subpixel. A hole injection layer 266G and a hole transport layer 268G are formed on the anode electrode 265G of the green subpixel. A hole injection layer 266B and a hole transport layer 268B are formed on the anode electrode 265B of the blue subpixel.

As indicated by the dashed circle Fa, the organic light emitting layer 269R of the red subpixel covers the hole injection layer 266R and the hole transport layer 268R. Further, the organic light emitting layer 269G of the green subpixel covers the hole injection layer 266G and the hole transport layer 268G. Further, the organic light emitting layer 269B of the blue subpixel covers the hole injection layer 266B and the hole transport layer 268B. As a result, carrier leakage can be prevented even when a part of the hole injection layer / hole transport layer of the sub-pixels having different colors overlaps due to a cause such as misalignment of the metal mask. That is, if the distance between the two sub-pixels is shortened in order to realize high definition, the hole supply layers of the adjacent sub-pixels may partially overlap. However, even in this case, as described with reference to FIG. 8C, the leak path can be blocked by laminating the organic light emitting layer having a small carrier mobility between the hole supply layers of different colors.

FIG. 13 schematically shows an example of the cross-sectional structure of the TFT substrate 100. An electron supply layer is formed for each sub-pixel. The red sub-pixel, the green sub-pixel, and the blue sub-pixel include the electron supply layer 271R, the electron supply layer 271G, and the electron supply layer 271B, respectively, and these are separated from each other.

As indicated by the broken line circle Fb, the cathode electrode 273 is in contact with the pixel definition layer 253. The cathode electrode 273 is formed between the hole transport layer 268R and the hole transport layer 268G. With this structure, for example, the current leaked from the hole transport layer 268R is drawn to the cathode electrode 273, so that it does not flow to the hole transport layer 268G of the green subpixel next to the red subpixel. That is, the leakage current does not flow between the adjacent sub-pixels. The layer structure on the pixel definition layer 253 is arbitrary as long as the hole injection layer / hole transport layer of the adjacent pixels does not overlap (if they are separated) at all.

FIG. 14 schematically shows an example of the cross-sectional structure of the TFT substrate 100. The electron supply layer 271 is common to all sub-pixels. As indicated by the dashed circle Fc, the electron supply layer 271 is in contact with the pixel definition layer 253. An electron supply layer 271 is formed between the hole transport layer 268R and the hole transport layer 268G. With this structure, for example, the current in the hole transport layer 268R is suppressed from flowing to the hole transport layer 268G of the green subpixel adjacent to the red subpixel.

That is, it suppresses the leakage current from flowing between adjacent sub-pixels via the electron supply layer 271. Since the resistance of the electron supply layer 271 is large (energy barrier), such suppression can be realized. The layer structure on the pixel definition layer 253 is arbitrary as long as the hole injection layer / hole transport layer of the adjacent pixels does not overlap (if they are separated) at all.

FIG. 15 schematically shows an example of the cross-sectional structure of the TFT substrate 100. The red subpixel includes a lower hole transport layer 681R and an upper hole transport layer 682R, which are two hole transport layers, between the organic light emitting layer 269R and the hole injection layer 266R. The green subpixel includes a lower hole transport layer 681G and an upper hole transport layer 682G, which are two hole transport layers, between the organic light emitting layer 269G and the hole injection layer 266G. The blue subpixel includes a hole transport layer 681B having only one layer between the organic light emitting layer 269B and the hole injection layer 266B. The cathode electrode and the electron supply layer 273a are in contact with the organic light emitting layer 269R, 269G, and 269B. As described above, the electron supply layer is composed of an electron injection layer and an electron transport layer, or is composed of one or three or more layers having the functions of these layers.

The hole injection layer (266R, 266G, 266B) of each color, the lower hole transport layer (681R, 681G), and the blue hole transport layer 681B are formed in a separated state using the same metal mask. There is. The organic light emitting layer 269R and the hole transport layer 682R of the red subpixel are formed by using the same metal mask. The organic light emitting layer 269G and the hole transport layer 682G of the green subpixel are formed by using the same metal mask. The organic light emitting layer 269 B of the blue subpixel is formed independently without sharing the metal mask with other layers.

As described above, the lower hole transport layer (681R, 681G) is commonly formed for the red and green sub-pixels, and the one-layer hole transport layer 681B is commonly formed for the blue pixel, and the red and green sub-pixels are further formed. The sub-pixels form an upper hole transport layer ( 682 R, 682 G). By this formation, the film thickness of the hole transport layer of each color is adjusted to realize the microcavity structure. The cathode electrode and the electron supply layer 273a are formed in a non-separable state (so-called common layer) by using the same metal mask.

Here, the deviation that occurs when the metal mask is placed on the substrate, that is, the deviation that occurs when the substrate and the metal mask are overlapped with each other will be described. When arranging the metal mask with respect to the substrate, it is difficult to eliminate the arrangement deviation. Therefore, in the design of this arrangement, the allowable condition for the arrangement deviation is determined. As an example of the allowable condition, there are a strict allowable condition (for example, a deviation of +/- 2 um or less) and a loose allowable condition (for example, a deviation of +/- 5 um or less).

The organic light emitting layer 269R and the hole transport layer 682R of the red subpixel are formed by using a metal mask that can be positioned so as to satisfy a strict tolerance condition. The organic light emitting layer 269G and the hole transport layer 682G of the green sub-pixels are misaligned on the blue sub-pixel side (right side in FIG. 15) and are positioned so as not to satisfy the strict tolerance conditions but to satisfy the loose tolerance conditions. It is formed using a metal mask that has been made. Similarly, the organic light emitting layer 269R of the red sub-pixel has a misalignment on the green sub-pixel side (right side in FIG. 15), and is a metal mask positioned so as not to satisfy the strict allowable condition but to satisfy the loose allowable condition. Is formed using.

In the adjacent sub-pixels, the end of the anode electrode of the first sub-pixel (for example, the red sub-pixel) and the end of the anode electrode of the second sub-pixel (for example, the green sub-pixel) adjacent to the first sub-pixel. The hole supply layer and the organic light emitting layer are vapor-deposited so that the separated portions of the hole supply layer and the organic light emitting layer are accommodated in the region RNG1 between them.

FIG. 16 schematically shows an example of the cross-sectional structure of the TFT substrate 100. The cathode electrode and the electron supply layer 273a are in contact with the organic light emitting layer 269R, 269G, and 269B. The organic light emitting layer 269R, the hole transport layer 268R, and the hole injection layer 266R of the red subpixel are formed by using the same metal mask. The organic light emitting layer 269G, the hole transport layer 268G, and the hole injection layer 266G of the green subpixel are formed by using the same metal mask.

The organic light emitting layer 269B, the hole transport layer 268B, and the hole injection layer 266B of the blue subpixel are formed by using the same metal mask. The cathode electrode and the electron supply layer 273a are formed in a non-separable state (so-called common layer) by using the same metal mask.

The organic light emitting layer 269R, the hole transport layer 268R, and the hole injection layer 266R of the red sub-pixels have misalignment on the green sub-pixel side (right side of FIG. 16 ) and do not meet strict tolerance conditions, but are loose. It is formed using a metal mask that can be positioned to meet the permissible conditions.

The organic light emitting layer 269G, the hole transport layer 268G, and the hole injection layer 266G of the green subpixel are formed by using a metal mask that can be positioned so as to satisfy a strict tolerance condition. The organic light emitting layer 269B, the hole transport layer 268B, and the hole injection layer 266B of the blue subpixel do not meet the strict tolerance conditions but are loose because the green subpixel side (left side of FIG. 16 ) is misaligned. It is formed using a metal mask that is positioned to meet acceptable conditions.

Even if the alignment deviation described above occurs, in the past, it was not possible to manufacture a non-defective product unless strict tolerance conditions were met, but by adopting the configuration of the present application, as long as loose tolerance conditions are met, Since organic light emitting layers of different colors can be separated, good products can be obtained and the manufacturing yield is improved.

<Embodiment 4>
First, the outline of the fourth embodiment will be described. In order to achieve high definition, the distance between the sub-pixels is shortened. When this distance is shortened, the organic light emitting layer of a certain sub-pixel may enter the hole supply layer of the sub-pixel adjacent to the sub-pixel, as shown in FIG. 8C, due to a cause such as misalignment of the metal mask. be. In the fourth embodiment, a laminated structure that further suppresses deterioration of image quality due to crosstalk between sub-pixels even when intrusion occurs will be described.

In order to make the OLED element emit light, it is necessary to pass a current through the OLED element at a emission threshold voltage or higher. The light emission threshold voltage means a voltage at which the OLED element emits light when a current flows above this voltage. For example, in order to cause the blue sub-pixel 251B to emit light, it is necessary to pass a current from the anode electrode 265B to the cathode electrode 273 (see FIG. 8) at a voltage equal to or higher than the emission threshold voltage of the blue sub-pixel 251B. The emission threshold voltage (hereinafter, appropriately referred to as the threshold voltage) of the sub-pixels of different colors is different. For example, the threshold voltage of the blue OLED element is higher than the threshold voltage of the green OLED element. The threshold voltage of the green OLED element is higher than the threshold voltage of the red OLED element.

In the fourth embodiment, the crosstalk between the sub-pixels is suppressed by devising the layer structure such as the organic light-emitting layer of each color by utilizing the fact that the emission threshold voltages of the sub-pixels of different colors are different. Hereinafter, the configuration of the display area and the manufacturing method of the fourth embodiment will be described. Differences from the first embodiment will be mainly described.

FIG. 17 shows a plan view of a part of the display area 125. FIG. 17 shows a plurality of sub-pixels arranged in a matrix. FIG. 17 shows a red sub-pixel (light emitting region) 251R, a blue sub pixel (light emitting region) 251B, and a green sub pixel (light emitting region) 251G. Of the sub-pixels in FIG. 17, only one sub-pixel of each of red, blue, and green is designated by a reference numeral.

In the layout of the sub-pixels shown in FIG. 17, the plurality of sub-pixels are arranged in a matrix. Unlike the layout shown in FIG. 2A in the first embodiment, the sub-pixels of the same color are not arranged even in the column direction (vertical direction in FIG. 17). That is, the red sub-pixel 251R is adjacent to the blue sub-pixel 251B in the matrix direction, and the green sub-pixel 251G is adjacent to the blue sub-pixel 251B in the matrix direction. The row direction is the X direction, and the column direction is the Y direction.

In other words, in the pixel layout of FIG. 17, the blue sub-pixel 251B having the highest threshold voltage among the threshold voltages of the red sub-pixel 251R, the blue sub-pixel 251B, and the green sub-pixel 251G is the red sub-pixel 251R and the green sub-pixel. It is arranged so as to surround 251G. It should be noted that two blue sub-pixels adjacent to each other in the diagonal direction, one red sub-pixel and one green sub-pixel adjacent to each other in the diagonal direction constitute one main pixel. In FIG. 17, a one-dot chain line shows one main pixel 600.

FIG. 18 shows a first cross-sectional view taken along the XVIII-XVIII cut line in FIG. In the fourth embodiment, the layer structure in which the red organic light emitting layer 269R and the green organic light emitting layer 269G are laminated on the upper layer (upper layer) of the blue organic light emitting layer 269B is schematically shown. In other words, the blue organic light emitting layer 269B is laminated on the lower layer (lower layer) of the red organic light emitting layer 269R and the green organic light emitting layer 269G. The upper side is indicated by an arrow UP, and the lower side is indicated by an arrow DW.

For example, as shown by the reference numeral RB1 indicated by the one-point chain line, the upper side of the top surface 253a1 of the first pixel definition portion 253a arranged between the blue subpixel 251B and the red subpixel 251R adjacent to the blue subpixel 251B. In, the end of the blue organic light emitting layer 269B of the blue subpixel 251B and the hole supply layer of the red subpixel 251R (for example, the hole injection layer 266R and the hole transport layer 268R of the red subpixel) are in contact with each other. ..

Further, as indicated by the reference numeral BG1 indicated by the one-point chain line, the top surface 253b 1 of the second pixel definition portion 253b arranged between the blue subpixel 251B and the green subpixel 251G adjacent to the blue subpixel 251B. On the upper side of the above, the end of the blue organic light emitting layer 269B of the blue sub-pixel 251B and the hole supply layer of the green sub-pixel 251G (for example, the hole injection layer 266G and the hole transport layer 268G of the green sub-pixel) are in contact with each other. ing.

When the red sub-pixel 251R is made to emit light and the blue sub-pixel 251B (or the green sub-pixel 251G) is not made to emit light, the pixel circuit (not shown) of the red sub-pixel 251R has a threshold voltage of the red sub-pixel 251R or more and the blue sub -pixel 251B. A current less than the threshold voltage of No. 1 (hereinafter referred to as a drive current of the red sub-pixel) is passed from the anode electrode 265R to the cathode electrode 273a. Due to this current, the red organic light emitting layer 269R emits light.

As shown by reference numeral RB1, the left end of the blue organic light emitting layer 269B is in contact with the hole injection layer 266R and the hole transport layer 268R. Therefore, even if the contact area is small, the drive current of the red sub -pixel 251R may flow into the blue organic light emitting layer 269B when the red sub-pixel 251R emits light. However, since the voltage of the drive current of the red sub-pixel 251R is smaller than the threshold voltage of the blue sub -pixel 251B, the blue sub -pixel 251B does not emit light.

That is, it is possible to suppress unintended light emission of the adjacent blue sub -pixel 251B when the red sub-pixel 251R emits light. It is assumed that the blue sub-pixel 251B emits light and the red sub-pixel 251R does not emit light. In this case, as described with reference to FIG. 2, since the energy barrier to holes is large, holes hardly move from the organic light emitting layer to the hole supply layer. Therefore, the drive current of the blue sub-pixel 251B does not flow to the hole injection layer 266R.

In order to form the layer structure shown in FIG. 18, the hole transport layer and the organic light emitting layer are vapor-deposited using a metal mask for each color. That is, a hole injection layer, a hole transport layer, and an organic light emitting layer of the same color are vapor-deposited using one metal mask. For the metal mask for the red sub-pixel, refer to FIG. 3A.

However, at the time of manufacture, the hole injection layer and the hole transport layer may be vapor-deposited in the first chamber, and the organic light emitting layer may be vapor-deposited in a second chamber different from the first chamber. Further, it is preferable that the end of the hole supply layer including the hole injection layer and / or the hole transport layer is surely covered with the organic light emitting layer. Therefore, the hole supply layer and the organic light emitting layer of the same color are vapor-deposited using two different metal masks.

FIG. 19 shows a second cross-sectional view taken along the XVIII-XVIII cut line in FIG. FIG. 19 describes a structure in which the edge of the hole supply layer is surely covered with the organic light emitting layer. FIG. 19 schematically shows a layer structure in which the red organic light emitting layer 269R and the green organic light emitting layer 269G are laminated on the upper layer of the blue organic light emitting layer 269B, as described in the cross-sectional view of FIG. .. As shown in FIG. 19, the thickness of the end portion of the organic light emitting layer that covers the entire end of the hole transport layer is increased. For example, as indicated by reference numeral RB2, the thickness of the end portion 269R1 of the red organic light emitting layer 269R that covers the entire right end of the hole transport layer 268R is increased. By increasing the thickness of the end portion of the organic light emitting layer in this way, the leak path is surely blocked.

20 and 21 are views illustrating a metal mask used to form the layer structure described in the cross-sectional view of FIG. The metal mask 47 of FIG. 20 is a metal mask used for forming, for example, a hole supply layer for blue. The metal mask 47 has an opening 461B for the hole supply layer of the blue subpixel. The vertical length of the opening 461B is L1 and the horizontal length is W1.

Next, the metal mask 49 in FIG. 21 is a metal mask used for forming, for example, an organic light emitting layer for blue. The metal mask 49 has an opening 463B for the organic light emitting layer of the blue subpixel. The vertical length of the opening 463B is L2, which is longer than the length L1. The lateral length of the opening 463B is W2, which is longer than the length W1.

In this way, by making the vertical and horizontal width of the opening of the metal mask for the hole supply layer larger than the vertical and horizontal width of the opening of the metal mask for the organic light emitting layer, the organic light emitting layer covering the entire end of the hole transport layer is covered. Increase the thickness of the edges of the mask.

In the layer structure of the fourth embodiment, as described with reference to FIGS. 18 and 19, the red organic light emitting layer 269R and the green organic light emitting layer 269G are laminated on the upper layer (upper layer) of the blue organic light emitting layer 269B. In order to realize this layer structure, first, the hole supply layer of the blue subpixel and the organic light emitting layer are formed, and then the hole supply layer of the green subpixel and the red subpixel and the organic light emitting layer are formed. do.

Hereinafter, the manufacturing process after forming the pixel definition layer 253 in the fourth embodiment will be described with reference to the flowchart of FIG. 22. First, the hole supply layer of the blue subpixel is formed on the insulating substrate 261 on which the pixel definition layer 253 is formed (S161). Specifically, the material of the hole supply layer is adhered to the substrate 261 on which the pixel definition layer 253 is formed by vapor deposition via the metal mask 47 corresponding to the pattern of the blue sub- pixels shown in FIG. 20. A hole supply layer for blue sub-pixels is formed. When the hole supply layer is composed of a plurality of layers including a hole injection layer and a hole transport layer, the plurality of layers are repeatedly formed. The thickness of the hole supply layer may be controlled due to the microcavity structure.

Next, the organic light emitting layer of the blue subpixel is formed (S162). Specifically, the material of the blue organic light emitting layer is adhered to the hole supply layer of the blue subpixel by vapor deposition via the metal mask 49 corresponding to the pattern of the blue subpixel shown in FIG. 21 . A blue organic light emitting layer is formed.

Next, the hole supply layer of the green sub-pixel is formed on the insulating substrate 261 on which the pixel definition layer 253 is formed (S163), the organic light emitting layer of the green sub-pixel is formed (S164), and the hole supply of the red sub-pixel is performed. A layer is formed (S165), an organic light emitting layer of red subpixels is formed (S166), an electron supply layer 271 common to all subpixels is formed (S167), and the electron supply layer 271 is used for the cathode electrode 273. A metal material is attached (S168).

Since the details of the steps from steps S163 to S168 have been described in S102, S105, S103, S106, S107, and S108 of FIG. 5, respectively, detailed description of these steps will be omitted. The order of the formation of the hole supply layer of the green subpixel and the organic light emitting layer (S163, S164) and the formation of the hole supply layer of the red subpixel and the organic light emitting layer (S165, S166) is changed. Good (in no particular order).

As described above, in the fourth embodiment, since the organic layers of each color are laminated by paying attention to the emission threshold voltage of each color, the image quality is deteriorated due to the crosstalk between the sub-pixels even when the different light emitting layers overlap. Can be further suppressed.

The display area 125 described in each of the above embodiments has a top emission type pixel structure. In the top emission type pixel structure, a cathode electrode 273 common to a plurality of pixels is arranged on the side where light is emitted (upper side in the drawing). The cathode electrode 273 has a shape that completely covers the entire surface of the display area 125. The features of the present disclosure can also be applied to an OLED display device having a bottom emission type pixel structure. The bottom emission type pixel structure has a transparent anode electrode and a reflective cathode electrode, and emits light to the outside through the TFT substrate 100.

The pixel array of the display area 125 described in each of the above embodiments is a so-called stripe array in which sub-pixel sequences of three colors are cyclically arranged. The features of the present disclosure can be applied to a pixel array composed of a pixel array including sub-pixels of different colors, and can be applied to various pixel arrays such as a mosaic array and a pental array.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. A person skilled in the art can easily change, add, or convert each element of the above embodiment within the scope of the present invention. It is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment.

10 OLED display device, 41, 43, 45 metal mask, 100 TFT substrate, 114 cathode electrode formation region, 125 display region, 131 scan driver, 132 emission driver, 133 protection circuit, 200 sealed substrate, 251B blue sub-pixel, 251G Green sub-pixel, 251R red sub-pixel, 253 pixel definition layer, 261 insulation substrate, 263 circuit layer, 265R red sub-pixel anode electrode, 265B blue sub-pixel anode electrode, 265G green sub-pixel anode electrode, 266R red sub-pixel Hole injection layer, 266G green sub-pixel hole injection layer, 266B blue sub-pixel hole injection layer, 267B blue sub-pixel hole supply layer, 267G green sub-pixel hole supply layer, 267R red sub-pixel Hole supply layer, 268R red sub-pixel hole transport layer, 268G green sub-pixel hole transport layer, 268B blue sub-pixel hole transport layer, 269B blue organic light emitting layer, 269G green organic light emitting layer, 269R red Organic light emitting layer, 271 electron supply layer, 273 cathode electrode, 300 junction, 412B blue sub-pixel opening, 412G green sub-pixel opening, 412R red sub-pixel opening, 452 opening

Claims (13)

With multiple sub-pixels arranged on the surface of the board,
A pixel definition layer that surrounds a light emitting region of each of the plurality of sub-pixels is included.
Each of the plurality of sub-pixels
With the upper electrode
With the lower electrode
An organic light emitting layer laminated with the upper electrode and the lower electrode between the upper electrode and the lower electrode,
The lower electrode and the lower carrier supply layer laminated with the organic light emitting layer are included between the lower electrode and the organic light emitting layer.
The lower carrier supply layer is
In contact with each of the lower electrode and the organic light emitting layer,
A carrier is supplied from the lower electrode to the organic light emitting layer, and the carrier is supplied.
The entire surface of the lower electrode in the opening of the pixel definition layer is covered.
It has an end on the top surface of the pixel definition layer that surrounds the lower electrode.
The organic light emitting layer covers the entire surface of the lower carrier supply layer including the end of the lower carrier supply layer.
The first end including the end of the lower carrier supply layer overlaps with the second end of the lower carrier supply layer of adjacent sub-pixels of different colors on the top surface of the pixel definition layer.
A part of the organic light emitting layer is laminated between the first end portion and the second end portion so that the first end portion is separated from the second end portion.
OLED display device. With multiple sub-pixels arranged on the surface of the board,
A pixel definition layer that surrounds a light emitting region of each of the plurality of sub-pixels is included.
Each of the plurality of sub-pixels
With the upper electrode
With the lower electrode
An organic light emitting layer laminated with the upper electrode and the lower electrode between the upper electrode and the lower electrode,
The lower electrode and the lower carrier supply layer laminated with the organic light emitting layer are included between the lower electrode and the organic light emitting layer.
The lower carrier supply layer is
In contact with each of the lower electrode and the organic light emitting layer,
A carrier is supplied from the lower electrode to the organic light emitting layer, and the carrier is supplied.
The entire surface of the lower electrode in the opening of the pixel definition layer is covered.
It has an end on the top surface of the pixel definition layer that surrounds the lower electrode.
The organic light emitting layer covers the entire surface of the lower carrier supply layer including the end of the lower carrier supply layer.
The end of the lower carrier supply layer is separated from the lower carrier supply layer of adjacent sub-pixels of different colors in the in-plane direction of the substrate.
The end of the organic light emitting layer is formed on the top surface of the pixel definition layer between the end of the lower carrier supply layer and the lower carrier supply layer of the adjacent different color sub-pixels.
OLED display device. With multiple sub-pixels arranged on the surface of the board,
A pixel definition layer that surrounds a light emitting region of each of the plurality of sub-pixels is included.
Each of the plurality of sub-pixels
With the upper electrode
With the lower electrode
An organic light emitting layer laminated with the upper electrode and the lower electrode between the upper electrode and the lower electrode,
The lower electrode and the lower carrier supply layer laminated with the organic light emitting layer are included between the lower electrode and the organic light emitting layer.
The lower carrier supply layer is
In contact with each of the lower electrode and the organic light emitting layer,
A carrier is supplied from the lower electrode to the organic light emitting layer, and the carrier is supplied.
The entire surface of the lower electrode in the opening of the pixel definition layer is covered.
It has an end on the top surface of the pixel definition layer that surrounds the lower electrode.
The organic light emitting layer covers the entire surface of the lower carrier supply layer including the end of the lower carrier supply layer.
At least three sub-pixels are sub-pixels that emit different first to third colors.
The organic light emitting layer of the sub-pixel of the first color covers the entire surface including the end of the lower carrier supply layer of the sub-pixel of the first color.
On the upper side of the top surface of the first pixel definition portion arranged between the sub-pixel of the first color and the sub-pixel of the second color adjacent to the sub-pixel of the first color, the sub-pixel of the first color The end of the organic light emitting layer of the sub-pixel and the lower carrier supply layer of the sub-pixel of the second color come into contact with each other.
The emission threshold voltage of the sub-pixel of the first color is higher than the emission threshold voltage of the sub-pixel of the second color.
OLED display device. The OLED display device according to claim 3.
On the upper side of the top surface of the second pixel definition portion arranged between the sub-pixel of the first color and the sub-pixel of the third color adjacent to the sub-pixel of the first color, the sub-pixel of the first color The end of the organic light emitting layer of the sub-pixel and the lower carrier supply layer of the sub-pixel of the third color come into contact with each other.
The emission threshold voltage of the sub-pixel of the first color is higher than the emission threshold voltage of the sub-pixel of the third color.
OLED display device. The OLED display device according to claim 4.
The plurality of sub-pixels are arranged in a matrix.
The second color sub-pixel is adjacent to the first color sub-pixel in the matrix direction.
The third color sub-pixel is adjacent to the first color sub-pixel in the matrix direction.
OLED display device. The OLED display device according to claim 2.
An upper carrier supply common to the plurality of sub-pixels, which is laminated in contact with the organic light-emitting layer and the upper electrode between the organic light-emitting layer of the plurality of sub-pixels and the upper electrodes of the plurality of sub-pixels. Including more layers,
The upper electrode of each of the plurality of sub-pixels is a part of one common upper electrode layer.
The end of the organic light emitting layer of each of the plurality of sub-pixels is formed between the end of the upper carrier supply layer and the end of the lower carrier supply layer on the top surface of the pixel definition layer. ,
OLED display device. The OLED display device according to claim 1, 2 or 3.
An upper carrier supply common to the plurality of sub-pixels, which is laminated in contact with the organic light-emitting layer and the upper electrode between the organic light-emitting layer of the plurality of sub-pixels and the upper electrodes of the plurality of sub-pixels. Including more layers,
The upper electrode of each of the plurality of sub-pixels is a cathode electrode and is a part of one common cathode electrode layer.
The upper carrier supply layer is an electron supply layer, and is
The lower electrode is an anode electrode and is an anode electrode.
The lower carrier supply layer is a hole supply layer.
OLED display device. With multiple sub-pixels arranged on the surface of the board,
A pixel definition layer that surrounds a light emitting region of each of the plurality of sub-pixels is included.
Each of the plurality of sub-pixels
With the upper electrode
With the lower electrode
An organic light emitting layer laminated with the upper electrode and the lower electrode between the upper electrode and the lower electrode,
The lower electrode and the lower carrier supply layer laminated with the organic light emitting layer are included between the lower electrode and the organic light emitting layer.
The lower carrier supply layer is
In contact with each of the lower electrode and the organic light emitting layer,
A carrier is supplied from the lower electrode to the organic light emitting layer, and the carrier is supplied.
The entire surface of the lower electrode in the opening of the pixel definition layer is covered.
It has an end on the top surface of the pixel definition layer that surrounds the lower electrode.
The organic light emitting layer covers the entire surface of the lower carrier supply layer including the end of the lower carrier supply layer.
The organic light emitting layer and the lower carrier supply layer have a tapered shape on the top surface of the pixel definition layer.
The taper angle of the tapered shape in the direction in which the sub-pixels of different colors are arranged is steeper than the taper angle of the tapered shape in the direction in which the sub-pixels of the same color are arranged.
OLED display device. The OLED display device according to claim 1.
The lower carrier supply layer of the sub-pixels of different colors has different thicknesses.
OLED display device. It is a method of manufacturing an OLED display device.
The first step of forming the lower electrode of the sub-pixel on the substrate,
The second step of forming a pixel definition layer including an opening in which the lower electrode is exposed is formed on the substrate on which the lower electrode is formed.
A first lower carrier supply layer is formed on the first lower electrode of the sub-pixel of the first color and the pixel definition layer, and each of the first lower carrier supply layer is with the first lower electrode at the opening. The third step, which is in contact with the entire surface of the first lower electrode and has an end on the top surface of the pixel definition layer surrounding the first lower electrode.
A second lower carrier supply layer is formed on the second lower electrode of the sub-pixel of the second color and the pixel definition layer, and each of the second lower carrier supply layer is connected to the second lower electrode at the opening. The fourth step, which is in contact with the entire surface of the second lower electrode and has an end on the top surface of the pixel definition layer surrounding the second lower electrode.
A third lower carrier supply layer is formed on the third lower electrode of the sub-pixel of the third color and the pixel definition layer, and each of the third lower carrier supply layer is connected to the third lower electrode at the opening. The fifth step, which covers the entire surface of the third lower electrode in contact and has an end on the top surface of the pixel definition layer surrounding the third lower electrode.
The first organic light emitting layer of each of the sub-pixels of the first color that comes into contact with the first lower carrier supply layer and covers the entire surface of the first lower carrier supply layer including the end of the first lower carrier supply layer. The sixth step to form,
A seventh step of forming a second organic light emitting layer that contacts the second lower carrier supply layer and covers the entire surface of the second lower carrier supply layer including the end of the second lower carrier supply layer.
The eighth step of forming a third organic light emitting layer that comes into contact with the third lower carrier supply layer and covers the entire surface of the third lower carrier supply layer including the end of the third lower carrier supply layer.
Including
The third step is carried out by vapor deposition using the first metal mask.
The sixth step is performed by vapor deposition using a second metal mask having an opening larger than that of the first metal mask.
The fourth step is carried out by vapor deposition using a third metal mask.
The seventh step is performed by vapor deposition using a fourth metal mask having an opening larger than that of the third metal mask.
The fifth step is carried out by vapor deposition using a fifth metal mask.
The eighth step is performed by vapor deposition using a sixth metal mask having an opening larger than that of the fifth metal mask.
Method. It is a method of manufacturing an OLED display device.
The first step of forming the lower electrode of the sub-pixel on the substrate,
The second step of forming a pixel definition layer including an opening in which the lower electrode is exposed is formed on the substrate on which the lower electrode is formed.
A first lower carrier supply layer is formed on the first lower electrode of the sub-pixel of the first color and the pixel definition layer, and each of the first lower carrier supply layer is with the first lower electrode at the opening. The third step, which is in contact with the entire surface of the first lower electrode and has an end on the top surface of the pixel definition layer surrounding the first lower electrode.
A second lower carrier supply layer is formed on the second lower electrode of the sub-pixel of the second color and the pixel definition layer, and each of the second lower carrier supply layer is connected to the second lower electrode at the opening. The fourth step, which is in contact with the entire surface of the second lower electrode and has an end on the top surface of the pixel definition layer surrounding the second lower electrode.
A third lower carrier supply layer is formed on the third lower electrode of the sub-pixel of the third color and the pixel definition layer, and each of the third lower carrier supply layer is connected to the third lower electrode at the opening. The fifth step, which covers the entire surface of the third lower electrode in contact and has an end on the top surface of the pixel definition layer surrounding the third lower electrode.
The first organic light emitting layer of each of the sub-pixels of the first color that comes into contact with the first lower carrier supply layer and covers the entire surface of the first lower carrier supply layer including the end of the first lower carrier supply layer. The sixth step to form,
A seventh step of forming a second organic light emitting layer that contacts the second lower carrier supply layer and covers the entire surface of the second lower carrier supply layer including the end of the second lower carrier supply layer.
The eighth step of forming a third organic light emitting layer that comes into contact with the third lower carrier supply layer and covers the entire surface of the third lower carrier supply layer including the end of the third lower carrier supply layer.
Including
After the third step, the sixth step is executed.
After the sixth step, the fourth step is executed.
After the 4th step, the 7th step is executed.
After the 7th step, the 5th step is executed.
After the fifth step, the eighth step is executed.
Method. The method according to claim 10.
After the third step, the fourth step and the fifth step, the sixth step, the seventh step and the eighth step are executed.
Method. The method according to claim 10.
At least three sub-pixels are sub-pixels that emit different first to third colors.
The organic light emitting layer of the sub-pixel of the first color covers the entire surface including the end of the lower carrier supply layer of the sub-pixel of the first color.
On the upper side of the top surface of the first pixel definition portion arranged between the sub-pixel of the first color and the sub-pixel of the second color adjacent to the sub-pixel of the first color, the sub-pixel of the first color The end of the organic light emitting layer of the sub-pixel and the lower carrier supply layer of the sub-pixel of the second color come into contact with each other.
The emission threshold voltage of the sub-pixel of the first color is higher than the emission threshold voltage of the sub-pixel of the second color.
Method.

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