JP2019091807A - Organic EL display - Google Patents

Abstract

To provide an organic EL display that has improved productivity.SOLUTION: An organic EL display is formed of first to fourth sub-pixels, and has a first hole transport layer provided on first to fourth pixel electrodes, first to fourth light emitting layers provided on the first hole transport layer individually according to the first to fourth sub-pixels, a second hole transport layer provided between the first hole transport layer and second light emitting layer, and a third hole transport layer provided between the first hole transport layer and the third light emitting layer and fourth light emitting layer.SELECTED DRAWING: Figure 7

Description

  The present invention relates to an organic electroluminescent (organic EL) display device.

  Conventionally, as a display device, an organic EL display device (Organic Electroluminescence Display) using an organic electroluminescent material (organic EL material) for a light emitting element (organic EL element) of a display unit is known. Unlike a liquid crystal display device or the like, the organic EL display device is a so-called self-luminous display device which realizes display by causing an organic EL material to emit light. As one of such organic EL display devices, there is known a pixel arrangement structure in which sub-pixels emitting light of three primary colors of red, blue and green independently are arranged adjacently on one main surface of a substrate. . As a method of manufacturing a pixel arrangement structure, a method of forming an organic semiconductor material by a vapor deposition method or the like for each emission color of each sub pixel is known.

  Moreover, in order to make the color reproduction range wider than the conventional three-primary-color display method, in addition to the conventional three primary colors, a pixel consisting of four or more types of sub-pixels added with sub-pixels for displaying other colors independently. A multi-primary-color display liquid crystal display device is known.

JP, 2001-209047, A

  When such a multi-primary-color display method is realized in an organic EL display device, the types and the number of sub-pixels increase compared to the conventional three-primary-color display method. Need to be placed more densely. In the process of forming the light emitting layer (EL layer), when forming the organic semiconductor material of each sub pixel by the vapor deposition method, it is necessary to repeat the vapor deposition process using a fine mask for each luminescent color of each sub pixel Therefore, the size of the opening of the deposition mask is reduced, and the number of processes in the deposition process is also increased. Therefore, there is a problem that the productivity of the organic EL display device is reduced. In particular, since the organic EL material is very sensitive to moisture and oxygen, it is preferable to reduce the number of manufacturing steps and shorten the manufacturing tact even when the deposition step is performed in a vacuum environment.

  An object of the present invention is to provide an organic EL display device having a wide color reproduction range and improved productivity, in view of the above problems.

  In an organic EL display device according to an embodiment of the present invention, one pixel is disposed adjacent to a substrate, a first sub-pixel having a first light-emitting area that emits a first color independently, and a second color A second sub-pixel having a second light-emitting area for independently emitting light, a third sub-pixel having a third light-emitting area for independently emitting a third color, and a fourth light-emitting area for independently emitting a fourth color And the first to fourth sub-pixels are provided corresponding to the first to fourth light emitting regions on the substrate. A fourth pixel electrode, a counter electrode provided on the first to fourth pixel electrodes, and an organic layer provided between the first to fourth pixel electrodes and the counter electrode; The organic layer includes a first hole transport layer provided on the first to fourth pixel electrodes, and the first hole. The light emitting layer is provided between the first hole transporting layer and the second light emitting layer, and the first to fourth light emitting layers individually provided according to the first to fourth sub-pixels. And a third hole transport layer provided between the first hole transport layer, the third light emitting layer, and the fourth light emitting layer.

  In the organic EL display device according to one embodiment of the present invention, one pixel is disposed adjacent to the substrate, the first sub-pixel having a first light-emitting area emitting light of a first color independently, the first sub-pixel A second sub-pixel having a second light-emitting area that emits two colors independently, a third sub-pixel having a third light-emitting area that emits a third color independently, and a fourth light-emitting area that emits fourth color independently An organic EL display device comprising a fourth sub-pixel having a light emitting area, wherein the first to fourth sub-pixels are provided corresponding to the first to fourth light emitting areas on the substrate. The first to fourth pixel electrodes, the opposite electrode provided on the first to fourth pixel electrodes, and the organic layer provided between the first to fourth pixel electrodes and the opposite electrode The organic layer may be formed of a first hole transport layer provided on the first to fourth pixel electrodes, and A first light emitting layer provided in the first sub-pixel on a hole transport layer; a second hole transport layer provided in the second sub-pixel on the first hole transport layer; The second light emitting layer provided in the second sub pixel, the third hole transport layer provided in the third sub pixel, and the third light emitting layer provided in the third sub pixel and the fourth sub pixel And.

FIG. 1 is a perspective view showing an entire configuration of a display device according to an embodiment of the present invention. FIG. 1 is a cross-sectional view showing an entire configuration of a pixel area of a display device according to an embodiment of the present invention. FIG. 1 is a schematic plan view showing a pixel configuration of a display device according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing a pixel configuration of a display device. It is sectional drawing which shows the manufacturing method of the positive hole transport layer of a display apparatus. It is sectional drawing which shows the manufacturing method of the positive hole transport layer of a display apparatus. It is sectional drawing which shows the manufacturing method of the positive hole transport layer of a display apparatus. It is sectional drawing which shows the manufacturing method of the positive hole transport layer of a display apparatus. It is a top view which shows the manufacturing method of the light emitting layer of a display apparatus. It is a top view which shows the manufacturing method of the light emitting layer of a display apparatus. It is a top view which shows the manufacturing method of the light emitting layer of a display apparatus. It is a top view which shows the manufacturing method of the light emitting layer of a display apparatus. FIG. 1 is a schematic cross-sectional view showing a pixel configuration of a display device according to a first embodiment of the present invention. It is a figure which shows the manufacturing method of the positive hole transport layer of the display apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the positive hole transport layer of the display apparatus which concerns on 1st Embodiment of this invention. It is a figure which shows the manufacturing method of the positive hole transport layer of the display apparatus which concerns on 1st Embodiment of this invention. It is the schematic sectional drawing which showed the pixel structure of the display apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the positive hole transport layer of the display apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the positive hole transport layer of the display apparatus which concerns on 2nd Embodiment of this invention. It is a figure which shows the manufacturing method of the positive hole transport layer of the display apparatus which concerns on 2nd Embodiment of this invention. It is the schematic sectional drawing which showed the pixel structure of the display apparatus which concerns on 3rd Embodiment of this invention. It is a top view which shows the manufacturing method of the light emitting layer of the display apparatus which concerns on 3rd Embodiment of this invention. It is a top view which shows the manufacturing method of the light emitting layer of the display apparatus which concerns on 3rd Embodiment of this invention. It is a top view which shows the manufacturing method of the light emitting layer of the display apparatus which concerns on 3rd Embodiment of this invention. It is the schematic sectional drawing which showed the pixel structure of the display apparatus which concerns on 4th Embodiment of this invention. It is the schematic plan view which showed the pixel structure of the display apparatus which concerns on 5th Embodiment of this invention. It is a top view which shows the manufacturing method of the light emitting layer of the display apparatus which concerns on 5th Embodiment of this invention. It is a top view which shows the manufacturing method of the light emitting layer of the display apparatus which concerns on 5th Embodiment of this invention. It is a top view which shows the manufacturing method of the positive hole transport layer of the display apparatus which concerns on 5th Embodiment of this invention. It is a top view which shows the manufacturing method of the positive hole transport layer of the display apparatus which concerns on 5th Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings and the like. However, the present invention can be implemented in various modes without departing from the scope of the present invention, and the present invention is not construed as being limited to the description of the embodiments exemplified below. In addition, with respect to the drawings, the width, thickness, shape, etc. of each part may be schematically represented in comparison with the actual aspect in order to make the description clearer. It does not limit the interpretation of the invention. Furthermore, in the present specification and the drawings, elements that are the same as or similar to those described with reference to the drawings already described may be denoted by the same reference numerals and redundant description may be omitted.

  In the present invention, when one film is processed to form a plurality of films, the plurality of films may have different functions and roles. However, the plurality of films are derived from the film formed as the same layer in the same step, and have the same layer structure and the same material. Therefore, these multiple films are defined as existing in the same layer.

  In the present specification, expressions such as “upper” and “lower” at the time of describing the drawings express the relative positional relationship between the structure of interest and the other structures. In the present specification, in a side view, the direction from the insulating surface described later toward the sealing film is defined as “upper”, and the opposite direction is defined as “lower”. In the present specification and claims, when expressing an aspect in which another structure is disposed on a certain structure, in the case where it is simply referred to as “above”, in a certain structure, unless otherwise specified. It includes both the case where another structure is arranged immediately above and the case where another structure is arranged above another structure via another structure so as to be in contact with each other.

  In this specification, a state in which the display device is viewed from the direction perpendicular to the screen (display area) is referred to as “plan view”. Although the structure of the top emission display device is described in this specification, the present invention is not limited to this, and may be used for a bottom emission display device.

First Embodiment
A display device according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 8C.

[Overall Configuration of Display Device]
FIG. 1 is a perspective view showing a display device 100 according to an embodiment of the present invention. In the display device 100, the pixel portion 104 and the touch sensor 108 are disposed on one main surface of a substrate 102 having an insulating surface. In the pixel unit 104, a plurality of pixels 106 are arranged. The plurality of pixels 106 are arranged in, for example, the row direction and the column direction in the pixel unit 104. The touch sensor 108 is disposed to overlap the pixel portion 104. In other words, the touch sensor 108 is disposed so as to overlap with the plurality of pixels 106. In the touch sensor 108, a plurality of detection electrodes 107 are arranged in a matrix, and each is connected in the row direction or the column direction. Here, the pixel 106 and the touch sensor 108 are schematically represented, and the magnitude relationship thereof is not limited to that shown in FIG. Moreover, although the touch panel which is a display apparatus provided with the position input apparatus by a touch sensor is demonstrated as an Example here, this invention is not limited to a touch panel.

  The display device 100 includes a terminal area 112 to which a video signal, a signal of the touch sensor 108, and the like are input and output. The terminal region 112 is disposed at one end of one main surface of the substrate 102 having an insulating surface. In the terminal region 112, a plurality of terminal electrodes are arranged along the end of the substrate 102 having an insulating surface. The plurality of terminal electrodes of the terminal area 112 are connected to the flexible printed wiring board 114. The driver circuit 110 outputs a video signal to the pixel 106. The drive circuit 110 is attached to one main surface of the substrate 102 or the flexible printed wiring board 114.

  The substrate 102 having an insulating surface is made of a member such as glass or plastic (polycarbonate, polyethylene terephthalate, polyimide, polyacrylate or the like). When the material of the substrate 102 is plastic, it is possible to give flexibility to the display device 100 by thinning the substrate. That is, by using a plastic substrate as the substrate 102, a flexible display can be provided.

  A polarizing plate 116 including a polarizer may be provided on the pixel portion 104 and the touch sensor 108. For example, the polarizing plate 116 is configured of a polarizer exhibiting circular polarization. The polarizing plate 116 is formed of a film substrate containing a polarizer. By providing the polarizing plate 116 so as to overlap the pixel portion 104, reflection (mirror formation) of the display screen can be prevented.

  Although not shown in FIG. 1, the pixel 106 includes a display element and a circuit element. The touch sensor 108 is preferably an electrostatic capacitance type, and in the touch sensor 108, a sensing unit is configured by the first detection electrode 134 (Tx wiring) and the second detection electrode 140 (Rx wiring) (see FIG. 2). . An interlayer insulating layer is provided between the pixel portion 104 and the touch sensor 108 and arranged so as not to electrically short each other.

  Details of the pixel 106 are shown in FIG. As shown in FIG. 2, the organic EL element 150 is electrically connected to the transistor 146. The current flowing between the source and the drain is controlled by the video signal applied to the gate of the transistor 146, and the light emission luminance of the organic EL element 150 is controlled by this current. The first capacitive element 152 holds the gate voltage of the transistor 146, and the second capacitive element 154 is provided to prevent the potential of the pixel electrode 170 from being inadvertently changed. The second capacitive element 154 is not an essential component and can be omitted.

  As shown in FIG. 2, a base insulating layer 156 is provided on the first surface of the substrate 102. The transistor 146 is provided over the base insulating layer 156. The transistor 146 includes a structure in which the semiconductor layer 158, the gate insulating layer 160, and the gate electrode 162 are stacked. The semiconductor layer 158 is formed using amorphous or polycrystalline silicon, an oxide semiconductor, or the like. The source / drain wiring 164 is provided in the upper layer of the gate electrode 162 via the first insulating layer 166. A second insulating layer 168 as a planarization layer is provided on the source / drain wiring 164.

  The first insulating layer 166 and the second insulating layer 168 are interlayer insulating layers. The first insulating layer 166 is a kind of inorganic interlayer insulating layer, and is formed of an inorganic insulating material such as silicon oxide, silicon nitride, silicon oxynitride, or aluminum oxide. The second insulating layer 168 is a type of organic interlayer insulating layer, and is formed of an organic insulating material such as polyimide or acrylic. The interlayer insulating layer may be stacked in order of the first insulating layer 166 and the second insulating layer 168 from the substrate 102 side. By providing the second insulating layer 168 formed of an organic insulating material in the upper layer of the first insulating layer 166, unevenness due to the transistor 146 or the like is embedded, and the surface is planarized.

  The organic EL element 150 is provided on the top surface of the second insulating layer 168. The organic EL element 150 has a structure in which a pixel electrode 170 electrically connected to the transistor 146, an organic layer 172, and a counter electrode 174 are stacked. The organic EL element 150 is a two-terminal element, and the light emission is controlled by controlling the voltage between the pixel electrode 170 and the counter electrode 174. A partition layer (bank) 176 is provided on the second insulating layer 168 so as to cover the peripheral portion of the pixel electrode 170 and to expose the inner region. The inner region of the pixel electrode 170 exposed from the partition layer 176 corresponds to the light emitting region of each sub pixel. The counter electrode 174 is provided on the top surface of the organic layer 172. The organic layer 172 is provided from the region overlapping with the pixel electrode 170 to the upper surface portion of the partition layer 176. The partition layer 176 is formed of an organic resin material to cover the peripheral portion of the pixel electrode 170 and to form a smooth step at the end portion of the pixel electrode 170. Acrylic or polyimide is used as the organic resin material.

  The organic layer 172 is formed of a plurality of layers including a light emitting layer formed of an organic EL material, and functions as a light emitting portion of the light emitting element. The organic layer 172 is provided to cover the light emitting region LA, that is, to cover the opening of the insulating film in the light emitting region LA.

  The organic layer 172 is formed using a low molecular weight or high molecular weight organic material. When a low molecular weight organic material is used, various charges such as an electron injection layer, an electron transport layer, a hole injection layer, and a hole transport layer may be added to the organic layer 172 so as to sandwich the light emitting layer. Transport layer is included. The specific configuration of the organic layer 172 will be described later.

  In the display device of the present embodiment, the pixel electrode 170 functions as an anode (anode) that constitutes a light emitting element. The pixel electrode 170 has a different structure depending on whether it is a top emission type or a bottom emission type. In the present embodiment, the organic EL element 150 has a so-called top emission type structure in which the light emitted from the organic layer 172 is emitted to the counter electrode 174 side. Therefore, the pixel electrode 170 preferably has light reflectivity. For example, in the case of the top emission type, a metal film with high reflectance such as aluminum (Al), silver (Ag) or the like is used as the pixel electrode 170 or an indium oxide based transparent conductive film (for example, ITO) excellent in hole injection property A layered structure of a metal film and a transparent conductive film having a high work function, such as zinc oxide based transparent conductive film (for example, IZO, ZnO) is used. Conversely, in the case of the bottom emission type, the above-described transparent conductive film is used as the pixel electrode 170. In the present embodiment, a top emission type organic EL display device is described as an example, but the present invention is not limited to this, and the organic EL element 150 uses light emitted from the organic layer 172 as a pixel electrode. It may have a so-called bottom emission type structure of emitting to the 170 side.

  The counter electrode 174 functions as a cathode (cathode) that constitutes the organic EL element 150. Since the display device 100 of the present embodiment is of the top emission type, the counter electrode 174 is made of transparent ITO, IZO, or the like, which transmits light emitted from the organic layer 172 and transmits light. It is formed of a transparent conductive film. The counter electrode 174 is also provided on the partition layer 176 across the respective pixels 106. The counter electrode 174 is electrically connected to the external terminal through the lower conductive layer in the peripheral area near the end of the display area. As described above, in the present embodiment, the organic EL element 150 is configured by a part (anode) of the pixel electrode 170 exposed from the partition layer 176, the organic layer 172 (light emitting part) and the counter electrode 174 (cathode).

  The first capacitor element 152 is formed in a region where the semiconductor layer 158 and the first capacitor electrode 178 overlap, using the gate insulating layer 160 as a dielectric film. In addition, the second capacitance element 154 uses the third insulating layer 182 provided between the pixel electrode 170 and the second capacitance electrode 180 as a dielectric film, and is provided so as to overlap with the pixel electrode 170 and the pixel electrode. The capacitor electrode 180 is formed. The third insulating layer 182 is formed of an inorganic insulating material such as silicon nitride.

  A sealing layer 126 is provided in the upper layer of the organic EL element 150. The sealing layer 126 is provided to prevent moisture and the like from intruding into the organic EL element 150. The sealing layer 126 may have a structure in which the first inorganic insulating layer 128, the organic insulating layer 130, and the second inorganic insulating layer 132 are stacked from the organic EL element 150 side. The first inorganic insulating layer 128 and the second inorganic insulating layer 132 are formed of an inorganic insulating material such as silicon nitride, silicon oxynitride, or aluminum oxide. The first inorganic insulating layer 128 and the second inorganic insulating layer 132 are formed of films of these inorganic insulating materials by a sputtering method, a plasma CVD method, or the like.

  The organic insulating layer 130 is preferably formed of an acrylic resin, a polyimide resin, an epoxy resin, or the like. The organic insulating layer 130 is formed by a coating method such as spin coating or a vapor deposition method using an organic material source. The organic insulating layer 130 is formed in a predetermined region including the pixel portion 104 so as to cover the pixel portion 104 and to seal the end portion with the first inorganic insulating layer 128 and the second inorganic insulating layer 132. Is preferred.

  Although not shown in FIG. 2, a polarizing plate 116 is provided on the upper surface of the sealing layer 126 as shown in FIG. The polarizing plate 116 may appropriately include a color filter layer and a light shielding layer in addition to the polarizer.

  FIG. 3 is a partial plan view showing the configuration of the pixel section 104 in the display device 100 shown in FIG. The pixel unit 104 includes a plurality of pixels 106, and one pixel 106 includes four sub-pixels of 2 rows × 2 columns. In the present embodiment, the pixel 106 includes the sub-pixel 106R that independently emits red (R) light, the sub-pixel 106G that independently emits green (G) light, and the blue (B) light. It is comprised from four types of sub pixels of the sub pixel 106B which emits light, and the sub pixel 106Y which light-emits the light of yellow (Y) independently.

  The colors in which the four sub-pixels constituting the pixel 106 independently emit light are configured from three primary colors of light, R, G, and B, and one other color. One other color is preferably selected from any of these neutral colors. Although FIG. 3 shows a configuration in which four colors of RGBY are used as the sub-pixels, the present embodiment is not limited to this, and instead of yellow (Y) as the fourth color other than the three primary colors of light. Other intermediate colors such as magenta (M) and cyan (C) may be selected. Further, the pixel arrangement is not limited to the arrangement shown in FIG. 3, and may be another arrangement such as a stripe arrangement, a delta arrangement, a Bayer arrangement, or a pen tile structure.

  Although omitted in FIG. 3, a thin film transistor is provided as a switching element in each sub pixel. By turning on and off each of the sub-pixels 106R, 106G, 106B, and 106Y using thin film transistors, it is possible to emit light of any color corresponding to each sub-pixel and express various colors as one pixel.

  In FIG. 3, a region indicated by a dashed rectangular in each sub-pixel is a light-emitting area LA in which each sub-pixel emits light independently. Each sub-pixel is a light emitting area LA-B (light emitting area of blue sub pixel) that emits light of each color independently, LA-G (light emitting area of green sub pixel), LA-R (red sub pixel) Light emitting area) and LA-Y (light emitting area of yellow sub-pixel) (see FIGS. 4 and 7).

[Pixel configuration of display device of four-color display method]
FIG. 4 is a schematic cross-sectional view showing a pixel configuration of a display device of a multi-primary color display method having pixels of four types of sub-pixels. FIG. 4 is a cross-sectional view taken along the line A-A 'of FIG. 3 in the case of realizing the pixel layout shown in FIG. 3 in the display device of the four-color display method. In the case of realizing a pixel configuration using four colors of RGBY as sub-pixels in a four-color display system, as shown in FIG. 4, each light emitting layer 300R corresponds to each of four colors of RGBY in each sub-pixel. , 300G, 300B, and 300Y are provided. In addition, pixel electrodes 170B, 170G, 170R, and 170Y exposed from the partition layer 176 are provided in the light emitting regions LA-B, LA-G, LA-R, and LA-Y of the sub-pixels, respectively.

  In the display device of the four-color display method, the thickness of the hole injection layer from the hole transport layer provided between each light emitting layer and the pixel electrode 170 for each color in which the sub-pixels emit light independently is It is necessary to adjust film thicknesses different from one another for the purpose of adjusting the chromaticity due to optical interference. Generally, the longer the peak wavelength of the light emitting layer, the thicker the layer for optical interference control.

  In FIG. 4, between the light emitting layer 300B of the blue sub-pixel 106B and the pixel electrode 170B, the hole injection layer 210 and the hole transport layer 220c provided commonly to all the sub-pixels are stacked. Is provided. Here, the fact that the hole injection layer 210 and the hole transport layer 220c are provided in common to all the sub-pixels means that four adjacent sub-pixel regions constituting one pixel are viewed in plan view. The hole injection layer 210 and the hole transport layer 220c are disposed as the same layer that mutually connects the sub-pixels.

  In FIG. 4, the hole injection layer 210 and the holes provided commonly to all the sub-pixels between the light-emitting layer 300G and the pixel electrode 170G of the green sub-pixel 106G adjacent to the blue sub-pixel 106B. Hole transport layers 220G are individually provided on the transport layer 220c for adjusting the film thickness to an appropriate thickness to express green light. Between the light emitting layer 300R of the red sub-pixel 106R adjacent to the green sub-pixel 106G and the pixel electrode 170R, the hole injection layer 210 and the hole transport layer 220c provided commonly to all the sub-pixels. In addition, a hole transport layer 220R is separately provided to adjust the film thickness to an appropriate thickness to express red light. Between the light emitting layer 300Y of the yellow sub-pixel 106Y adjacent to the red sub-pixel 106R and the pixel electrode 170Y, the hole injection layer 210 and the hole transport layer 220c provided commonly to all the sub-pixels. In addition, a hole transport layer 220Y is separately provided to adjust the film thickness to an appropriate thickness to express yellow light.

  Further, as shown in FIG. 4, an electron transport layer 230, an electron injection layer 240, and a counter electrode 174, which are provided commonly to the respective sub-pixels, are provided on the respective light emitting layers. As shown in FIG. 4, the organic layer 172 is formed by laminating a plurality of layers including a hole injection layer 210, various hole transport layers 220, various light emitting layers 300, an electron transport layer 230, and an electron injection layer 340. Be done.

  5A to 5D are cross-sectional views showing a method of manufacturing the hole transport layer of the display device of the four-color display system shown in FIG. In order to realize the pixel configuration shown in FIG. 4, first, the hole injection layer 210 is formed as a layer common to all the sub-pixels on each pixel electrode 170 exposed from the partition layer 176 provided on the substrate. The hole transport layer 220c is formed on the hole injection layer 210 as a layer common to all the sub-pixels (FIG. 5A). Next, the hole transport layer 220G adjusted to a film thickness corresponding to green is formed in the green sub-pixel 106G region on the hole transport layer 220c (FIG. 5B). Next, the hole transport layer 220R adjusted to the film thickness corresponding to red is formed in the red sub-pixel 106R region on the hole transport layer 220c (FIG. 5C). Next, the hole transport layer 220Y adjusted to a film thickness corresponding to yellow is formed in the yellow sub-pixel 106Y region on the hole transport layer 220c (FIG. 5D). As described above, in order to manufacture the sub-pixel structure of four colors in the display device shown in FIG. 4, the hole transport layer 220 c is collectively formed as a layer common to all the sub-pixels, and then the hole transport layer is formed for each sub-pixel. In addition, three manufacturing steps are required to form the individual.

  6A to 6D are cross-sectional views showing a method of manufacturing a light emitting layer of the display device of the four-color display system shown in FIG. In order to realize the pixel configuration shown in FIG. 4, after forming the hole transport layer having a film thickness corresponding to each sub-pixel (FIG. 5D), the blue sub-pixel 106B region on the hole transport layer 220c is formed. A blue light emitting layer 300B is formed (FIG. 6A), a green light emitting layer 300G is formed on the hole transport layer 220G adjusted to a film thickness corresponding to green (FIG. 6B), and a film thickness corresponding to red The red light emitting layer 300R is formed on the adjusted hole transport layer 220R (FIG. 6C), and the yellow light emitting layer 300Y is formed on the hole transport layer 220Y adjusted to the film thickness corresponding to yellow. (FIG. 6D). As described above, in order to realize the four-color sub-pixel structure in the display device shown in FIG. 4, it is necessary to separately form the light-emitting layers made of different materials for each sub-pixel. Is also needed. Therefore, in the display device shown in FIG. 4, a total of seven steps are required for manufacturing the hole transport layer and the light emitting layer separately for each sub-pixel.

[Pixel Configuration of Display Device According to First Embodiment]
The first embodiment will be described with reference to FIGS. 7 to 8C. FIG. 7 is a schematic cross-sectional view showing the pixel configuration of the display device according to the first embodiment of the present invention. 7 is a cross-sectional view taken along the line A-A 'of FIG. 3 in the case of realizing the pixel layout shown in FIG. 3 in the display device according to the first embodiment. 8A to 8C are diagrams showing a method of manufacturing the hole transport layer of the display device according to the first embodiment of the present invention. As shown in FIG. 7, the configuration of the blue sub-pixel 106B and the green sub-pixel 106G of the present embodiment is the same as that of the display shown in FIG. In the sub-pixel 106R and the yellow sub-pixel 106Y ', one layer common to both sub-pixels is a hole transport layer 220RY' integrally formed under the red light-emitting layer 300R and the yellow light-emitting layer 300Y '. , And differs from the display device shown in FIG. Here, the fact that the hole transport layer 220RY 'is commonly provided to the red sub-pixel 106R and the yellow sub-pixel 106Y' means that the adjacent red sub-pixel 106R that constitutes one pixel in plan view In the yellow and yellow sub-pixels 106Y ', a hole transport layer 220RY' is disposed as the same layer connecting the respective sub-pixels to each other. The other configuration is the same as the configuration described for the display device shown in FIGS. 4 to 6D, and thus the description thereof will not be repeated.

  In the present embodiment, the hole transport layer 220RY 'for film thickness adjustment corresponding to the red sub-pixel 106R is the same as the hole transport layer 220RY' for film thickness adjustment corresponding to the adjacent yellow sub-pixel 106Y '. The red sub-pixel 106R and the hole transport layer 220RY 'corresponding to the yellow sub-pixel 106Y' can be simultaneously formed in the same process.

  A specific manufacturing method will be described with reference to FIGS. 8A to 8C. In order to manufacture the pixel configuration of this embodiment shown in FIG. 7, first, hole injection is performed as a layer common to all the sub-pixels on each pixel electrode 170 exposed from the partition layer 176 provided on the substrate. The layer 210 is formed, and the hole transport layer 220c is formed on the hole injection layer 210 as a layer common to all the sub-pixels (FIG. 8A). The film thickness of the hole transport layer 220c may be set to, for example, a film thickness (for example, 110 nm) suitable for emitting blue light in consideration of optical interference based on the blue sub-pixel 106B. .

  Next, the hole transport layer 220G adjusted to a film thickness corresponding to green is formed in the green sub-pixel 106G region on the hole transport layer 220c (FIG. 8B). The film thickness of the hole transport layer 220G is such that the sum of the film thickness of the hole transport layer 220c and the film thickness of the hole transport layer 220G is suitable for emitting green light in consideration of optical interference. The film thickness may be adjusted (for example, 25 nm).

  In general, an appropriate film thickness in consideration of optical interference is the thickness of each layer disposed between the light emitting layer and the metal layer (reflection layer) of the pixel electrode for the wavelength to be reflected for each sub-pixel and It is determined based on the refractive index.

  Next, a hole transport layer 220RY 'adjusted to a thickness corresponding to red is formed as a layer common to the red sub-pixel 106R region and the yellow sub-pixel 106Y' region on the hole transport layer 220c. (FIG. 8C). The film thickness of the hole transport layer 220RY 'is such that the sum of the film thickness of the hole transport layer 220c and the film thickness of the hole transport layer 220RY' is suitable for emitting red light in consideration of optical interference. The film thickness (for example, 80 nm) adjusted so that it may become may be sufficient. In particular, as shown in FIG. 8C, the hole transport layer 220RY 'is continuously disposed in the X direction of the substrate 102 in a plan view, and therefore, the hole transport layer 220RY' can be collectively deposited in the same direction with a large mask opening. By enlarging the mask opening, the process of forming the hole transport layer 220RY 'is simplified, and defects in the manufacturing process are reduced.

  As described above, in the case of manufacturing the four-color sub-pixel structure according to the present embodiment, the hole transport layer 220c is formed as a layer common to all the sub-pixels, and then the hole transport layer is separately formed for each sub-pixel. Since two manufacturing processes are sufficient, one process can be eliminated as compared with the display device shown in FIG. In the present embodiment, after forming the hole transport layer individually, as in the display device shown in FIG. 4, four steps of manufacturing steps are required to form the light emitting layer separately for each sub-pixel. Therefore, even in consideration of the manufacturing process of the light emitting layer, it is sufficient to use six processes which are reduced by one process from the seven processes of the display device shown in FIG. Therefore, according to the present embodiment, in the display device shown in FIG. 4, according to this embodiment, the manufacturing process for separately forming the hole transport layer and the light emitting layer for each sub-pixel requires seven processes, to six processes. It can be reduced. As a result, the manufacturing process for individually forming the hole transport layer is simplified, so that the manufacturing tact is shortened and the productivity of the organic EL display device is improved.

  As described above, in the present embodiment, the film thickness of the hole transport layer 220RY 'may be a film thickness adjusted for the purpose of adjusting the optical interference of the red light emitting layer 300R. In this case, the thickness of the organic layer provided under the yellow light emitting layer 300Y 'is set to the same thickness as the thickness of the organic layer provided under the red light emitting layer 300R. In LA-Y, the film thickness of the organic layer can not be adjusted individually. Therefore, as the material of the yellow light emitting layer 300Y 'in the present embodiment, a light emitting material capable of emitting a desired color is selected in consideration of color shift due to optical interference due to a preset film thickness. Ru.

  For example, as described above, in the case where the film thickness of the hole transport layer 220RY 'is adjusted for the purpose of adjusting the optical interference of the light emitting layer 300R of red, the red wavelength component in the yellow light emitting area LA-Y is In order to become stronger, it is necessary to reduce the red wavelength component or to form a yellow light emitting layer 300Y 'using a light emitting material whose peak wavelength is shifted in a shorter direction.

  In FIG. 7, the hole transport layer 220RY 'for film thickness adjustment is made common between the adjacent red sub-pixel 106R and the yellow sub-pixel 106Y', but in the present embodiment, the sub-pixel of this color is used. It is not limited to the combination of For example, in the case of a pixel configuration in which a green sub-pixel and a yellow sub-pixel are arranged adjacent to each other, a hole transport layer for film thickness adjustment is provided between the adjacent green sub-pixel and the yellow sub-pixel. It may be common. As described above, when different types of sub-pixels emitting light of adjacent hues are arranged adjacent to each other, the peak wavelengths of the light emitting layers of the adjacent sub-pixels are close to each other, and thus the hole transport layer is shared. It can be formed with the same film thickness. In this case, the material of the light emitting layer of the other sub pixel which commonly uses the film thickness suitable for the light emission color of one sub pixel is an appropriate color in consideration of the color shift due to the preset film thickness. A desired color can be expressed in each sub-pixel by selecting a light emitting material to emit light.

Second Embodiment
A display device according to a second embodiment of the present invention will be described with reference to FIGS. 9 to 10C.

[Pixel Configuration of Display Device According to Second Embodiment]
FIG. 9 is a schematic cross-sectional view showing a pixel configuration of a display device according to a second embodiment of the present invention. FIG. 9 is a cross-sectional view taken along the line A-A ′ of FIG. 3 when the pixel layout shown in FIG. 3 is realized in the display device according to the second embodiment. 10A to 10C are diagrams showing a method of manufacturing a hole transport layer of a display device according to a second embodiment of the present invention. The display device according to the second embodiment is the same as the display device shown in FIG. 4 in the configuration of the blue sub-pixel 106B of this embodiment as shown in FIG. 9, but in this embodiment it is the first embodiment. Similarly, in the red sub-pixel 106R and the yellow sub-pixel 106Y 'arranged adjacent to each other, separate hole transport layers 220RY' formed under the red light-emitting layer 300R and the yellow light-emitting layer 300Y '. In addition to being provided as one layer common to both sub-pixels, in the green sub-pixel 106G and the red sub-pixel 106R arranged adjacent to each other, the green light-emitting layer 300G and the red light-emitting layer A separate hole transport layer 220GR formed under 300R is provided as one layer common to both sub-pixels.

  Here, the fact that the hole transport layer 220GR is provided in common to the green sub-pixel 106G and the red sub-pixel 106R means that the adjacent green sub-pixel 106G and the red that form one pixel in plan view In the sub-pixel 106R region, the hole transport layer 220GR is disposed as the same layer connecting the sub-pixels to each other. The other configuration is the same as that of the first embodiment, and therefore the repetition of the common description will be omitted.

  In the present embodiment, as in the first embodiment, the hole transport layer 220RY 'for film thickness adjustment corresponding to the red sub-pixel 106R is for film thickness adjustment corresponding to the adjacent yellow sub-pixel 106Y'. In addition to being made common to the hole transport layer 220RY ', the film thickness adjustment corresponding to the red sub-pixel 106R the hole transport layer 220GR for film thickness adjustment corresponding to the green sub-pixel 106G And the common hole transport layer 220GR. Thus, a structure in which the hole transport layer 220GR common to the green sub-pixel and the hole transport layer 220RY 'common to the yellow sub-pixel are stacked under the red light emitting layer 300R. It becomes. In the present embodiment, the hole transport layer 220GR of the red sub-pixel 106R and the green sub-pixel 106R is made common, but the present invention is not limited to this combination, and two types of peak wavelengths of the light emitting layer are close. The hole transport layer of the sub-pixel can be made common.

  In order to manufacture the pixel configuration of the present embodiment shown in FIG. 9, first, hole injection is performed as a layer common to all the sub-pixels on each pixel electrode 170 exposed from the partition layer 176 provided on the substrate. After forming the layer 210 and forming the hole transport layer 220c on the hole injection layer 210 as a layer common to all the sub-pixels (FIG. 10A), the green sub-pixel 106G region on the hole transport layer 220c A hole transport layer 220GR adjusted to a film thickness corresponding to green is formed as a layer common to the red and red sub-pixels 106R (FIG. 10B). Next, a hole transport layer adjusted to have a film thickness corresponding to red on the hole transport layer 220GR as a layer common to the red sub-pixel 106R region and the yellow sub-pixel 106Y 'region Form 220RY '(FIG. 10C).

  In particular, as shown in FIG. 10B, the hole transport layer 220GR is continuously disposed in the Y direction in plan view, and therefore, the hole transport layer 220GR can be collectively deposited in the same direction with a large mask opening. Similarly, as shown in FIG. 10C, the hole transport layers 220RY 'are continuously disposed in the Y direction in plan view, and therefore, the hole transport layers 220RY' can be simultaneously deposited in the same direction with a large mask opening. Therefore, in the manufacturing process of hole transport layer 220GR and hole transport layer 220RY ', the process of forming each hole transport layer 220 is simplified by enlarging the mask opening respectively, and the process of manufacturing the hole transport layer Defects in the

  In this case, the film thickness of the hole transport layer individually formed in the red sub-pixel 106R region is the same as the film thickness of the hole transport layer 220GR shared with the green sub-pixel and the yellow sub-pixel While the hole transport layer 220GR does not exist in the yellow sub-pixel 106Y 'region while the film thickness is the sum of the film thickness of the hole transport layer 220RY' and the yellow sub-pixel 106Y 'region. The film thickness of the hole transport layer individually formed is the film thickness of the hole transport layer 220RY '. In the present embodiment, the hole transport layer 220GR is commonly used between the red sub-pixel 106R and the green sub-pixel 106G, but is not limited to the combination of the sub-pixels of this color, and the peak of the light emitting layer The hole transport layers of the light emitting layers close in wavelength to each other can be made common.

  As described above, in the case of manufacturing the four-color sub-pixel structure according to the present embodiment, the hole transport layer 220c is formed as a layer common to all the sub-pixels, and then the hole transport layer is separately formed for each sub-pixel. The number of manufacturing processes required is two, so one process can be eliminated as compared with the display device shown in FIG. In the present embodiment, after forming the hole transport layer individually, as in the display device shown in FIG. 4, four steps of manufacturing steps are required to form the light emitting layer separately for each sub-pixel. Therefore, even when considering the manufacturing process of the light emitting layer, it is sufficient to use six processes which are reduced by one process from the seven processes of the display device shown in FIG. Therefore, in the display device shown in FIG. 4, according to the present embodiment, the number of manufacturing processes for forming the hole transport layer and the light emitting layer separately for each sub-pixel is required to be seven, which is reduced to six. can do. As a result, the manufacturing process for individually forming the hole transport layer is further simplified, so that the manufacturing tact is shortened and the productivity of the organic EL display device is improved.

  Furthermore, in the present embodiment, the thickness of the hole transport layer individually formed in the red sub-pixel 106R region and the thickness of the hole transport layer individually formed in the yellow sub-pixel 106Y ′ region are calculated. Since the thickness can be adjusted to a different thickness, the film thickness adjustment of optical interference in the yellow sub pixel is easier as compared with the first embodiment. As a specific method of film thickness adjustment, for example, as described above, the film thickness of the hole transport layer 220GR common to the green sub-pixel 106G region and the red sub-pixel 106R region corresponds to the film thickness corresponding to green (For example, 25 nm), and the film thickness of the hole transport layer 220RY 'common to the red sub-pixel 106R region and the yellow sub-pixel 106Y' region is the film thickness of the hole transport layer 220GR (corresponding to green The film thickness is adjusted to be the film thickness (for example, 80 nm) corresponding to the film thickness of the hole transport layer 220RY '= red, and as a result, the hole transport layer 220RY' provided in the yellow sub-pixel 106Y 'region. The film thickness of (for example, 55 nm) may be adjusted to be the film thickness (for example, 80 nm) corresponding to red-the film thickness (for example 25 nm) corresponding to green. Also in this embodiment, as in the first embodiment, a chromaticity control method of selecting a material considering a color shift due to a preset film thickness as the material of the yellow light emitting layer 300Y 'is used in combination. You may

Third Embodiment
A display device according to a third embodiment of the present invention will be described with reference to FIGS. 11 to 12C.

[Pixel Configuration of Display Device According to Third Embodiment]
FIG. 11 is a schematic cross-sectional view showing a pixel configuration of a display device according to a third embodiment of the present invention. 11 is a cross-sectional view taken along the line A-A 'of FIG. 3 in the case of realizing the pixel layout shown in FIG. 3 in the display device according to the third embodiment. 12A to 12C are diagrams showing a method of manufacturing a light emitting layer of a display device according to a third embodiment of the present invention. In the display according to the third embodiment, as shown in FIG. 11, the configurations of the blue sub-pixel 106B and the green sub-pixel 106G of the present embodiment are the same as the display shown in FIG. Then, in the red sub-pixel 106R and the yellow sub-pixel 106Y 'arranged adjacent to each other, the red light-emitting layer 300R is provided as a light-emitting layer common to both sub-pixels, as shown in FIG. Different from the device. Here, the fact that the red light emitting layer 300R is provided in common to the red sub-pixel 106R and the yellow sub-pixel 106Y 'means that the red light-emitting layer 300R and the adjacent red sub-pixel 106R that constitute one pixel are viewed in plan view. It means that a red light emitting layer 300R is disposed in the yellow sub-pixel 106Y 'region as the same layer connecting the sub-pixels to each other.

  In the first embodiment and the second embodiment, the hole transport layer for film thickness adjustment provided individually for each sub-pixel is partially shared, but in the present embodiment, one light-emitting layer of each sub-pixel is used. The part is common.

  In the present embodiment, the red light emitting layer 300R corresponding to the red sub pixel 106R is shared with the light emitting layer of the adjacent yellow sub pixel 106Y '. In addition, since the film thickness of the organic layer provided in the light emitting area LA-Y of the yellow sub pixel is formed to be different from that of the light emitting area LA-R of the red sub pixel, the light emitting area of the yellow sub pixel The light emitted from LA-Y can be adjusted to a color different from the light emitted from the light emitting area LA-R of the red sub-pixel. The other configuration is the same as that of the first embodiment to the second embodiment, and therefore the repetition of the common description will be omitted.

  In the case of manufacturing the pixel configuration of the present embodiment shown in FIG. 11, the manufacturing process for individually forming the hole transport layer for film thickness adjustment for each of the four types of sub-pixels is shown in FIG. 4 and FIGS. It is the same as the manufacturing method of the hole transport layer in the display described. However, unlike the display device shown in FIG. 4, in the present embodiment, in the manufacturing process for individually forming the hole transport layer, the film thickness of the hole transport layer individually provided in the yellow sub-pixel region is In consideration of the common use of the red light emitting layer 300R on the upper side, the film thickness adjusted so as to realize a desired chromaticity is selected.

  Next, after manufacturing a hole transport layer, it demonstrates in the process of manufacturing a light emitting layer using FIG. 12A-FIG. 12C. In this embodiment, after separately forming the hole transport layer having a film thickness corresponding to each sub-pixel (FIG. 5D), the blue light-emitting layer 300B is formed in the blue sub-pixel 106B region on the hole transport layer 220c. (FIG. 12A), the green light emitting layer 300G is formed on the hole transport layer 220G adjusted to the film thickness corresponding to green (FIG. 12B), and the red sub-pixel 106R region and the yellow sub-pixel 106Y 'are formed. A red light emitting layer 300R is formed as a light emitting layer common to the region (FIG. 12C). In particular, as shown in FIG. 12C, since the red light emitting layer 300R is continuously arranged in the X direction in plan view, it is possible to form a film simultaneously in the same direction with a large mask opening. Therefore, in the manufacturing process of the red light emitting layer 300R, the process of forming the light emitting layer 300R is simplified by enlarging the mask opening, and defects in the manufacturing process of the light emitting layer are reduced.

  As described above, when manufacturing the four-color sub-pixel structure according to the present embodiment, three steps are sufficient to manufacture the light emitting layer for each sub-pixel, so one step is reduced compared to the display device shown in FIG. be able to. In the present embodiment, when separately forming the hole transport layer for adjusting the film thickness, the manufacturing process for forming the hole transport layer separately for each sub-pixel as in the display device shown in FIG. Although the process is required, since the light emitting layer is partially shared, even if the process of manufacturing the hole transport layer is taken into consideration, it is sufficient that the number of processes is one less than the seven processes of the display shown in FIG. Therefore, in the display device shown in FIG. 4, according to the present embodiment, the number of manufacturing processes for forming the hole transport layer and the light emitting layer separately for each sub-pixel is required to be seven, which is reduced to six. can do. As a result, the manufacturing process for individually forming the light emitting layers is simplified, so that the manufacturing tact is shortened and the productivity of the organic EL display device is improved.

  In FIG. 11, the red light emitting layer 300R is made common between the adjacent red sub-pixel 106R and the yellow sub-pixel 106Y ', but the present embodiment is limited to a combination of sub-pixels of this color. It is not a thing. For example, in the case of a pixel configuration in which a blue sub-pixel and a green sub-pixel are arranged adjacent to each other, the blue light-emitting layer may be shared between the adjacent blue sub-pixel and the green sub-pixel . In the case of a pixel configuration in which the green sub-pixel and the red sub-pixel are arranged adjacent to each other, the green light-emitting layer may be shared between the adjacent green sub-pixel and the red sub-pixel. . As described above, when different types of sub-pixels emitting adjacent hues are adjacently disposed, the peak wavelengths of the light-emitting layers of the adjacent sub-pixels are close to each other, so that the light-emitting layers can be shared. In this case, the thickness of the hole transport layer formed in the light emitting region of the other sub-pixel emitting light of another color by using the light emitting layer of one sub-pixel in common is the color of the light emitting layer set in advance. The desired color can be emitted by selecting the film thickness capable of expressing different colors in consideration of the above.

Fourth Embodiment
A display device according to a fourth embodiment of the present invention will be described with reference to FIG.

[Pixel Configuration of Display Device According to Fourth Embodiment]
FIG. 13 is a schematic cross-sectional view showing a pixel configuration of a display device according to a fourth embodiment of the present invention. FIG. 13 is a cross-sectional view taken along the line A-A ′ of FIG. 3 when the pixel layout shown in FIG. 3 is realized in the display device according to the fourth embodiment. In the display device according to the fourth embodiment, as shown in FIG. 13, the configuration of the blue sub-pixel 106 of this embodiment is the same as the display device shown in FIG. In each of the red sub-pixel 106R and the yellow sub-pixel 106Y ', the individual hole transport layers 220RY' formed under the red light-emitting layer 300R and the yellow light-emitting layer 300Y 'are both sub-pixels. In addition to being provided as one common layer, the green sub-pixel 106G and the red sub-pixel 106R disposed adjacent to each other are formed under the green light-emitting layer 300G and the red light-emitting layer 300R. A separate hole transport layer 220GR is provided as one layer common to both sub-pixels. Furthermore, in the present embodiment, as in the third embodiment, in the red sub-pixel 106R and the yellow sub-pixel 106Y ′ disposed adjacent to each other, the light-emitting layer in which the red light-emitting layer 300R is common to both sub-pixels It is provided as In the present embodiment, as in the second embodiment, the hole transport layer for film thickness adjustment separately provided in each sub-pixel is partially shared, and in the same manner as in the third embodiment, the light emitting layer of each sub-pixel Is also common. The other configurations are the same as those of the first to third embodiments, and therefore, the repetition of the common description will be omitted.

  In the present embodiment, as in the second embodiment, the hole transport layer for film thickness adjustment provided individually for each sub-pixel is formed between the red sub-pixel 106R and the adjacent yellow sub-pixel 106Y '. The hole transport layer 220RY 'is shared, and the hole transport layer 220GR is shared between the green sub-pixel 106G and the adjacent red sub-pixel 106R. By partially sharing the hole transport layer in this way, it is possible to reduce the number of manufacturing steps of the hole transport layer for film thickness adjustment by one step, and the common hole transport layer is viewed in plan In this case, the films can be formed simultaneously in the same direction with a large mask opening because they are continuously arranged in the X to Y directions. Therefore, in the manufacturing process of the common hole transport layer 220GR and the hole transport layer 220RY ', the formation process of each hole transport layer 220 is further simplified by enlarging the mask opening respectively, and the hole transport is performed. Defects in the layer manufacturing process are reduced.

  Furthermore, in the present embodiment, as in the third embodiment, the light emitting layer of each sub pixel is partially shared. By partially sharing the light emitting layer in this way, the number of manufacturing steps of the light emitting layer can be reduced by one step, and the common light emitting layer is continuously disposed in the X to Y direction in plan view Therefore, film formation can be performed simultaneously in the same direction with a large mask opening. Therefore, in the manufacturing process of the common light emitting layer 300R, by enlarging the mask opening, the process of forming the light emitting layer is simplified, and defects in the manufacturing process of the light emitting layer are reduced.

  As described above, according to the present embodiment, in the display device shown in FIG. 4, according to the present embodiment, a total of seven manufacturing steps are required for forming the hole transport layer and the light emitting layer separately for each sub-pixel. As it is sufficient, two steps can be reduced. Furthermore, according to the present embodiment, since the hole transport layer is partially shared and the light emitting layer is partially shared between the sub-pixels, the mask opening when forming each layer can be expanded. The respective manufacturing steps can be simplified to improve the yield.

Fifth Embodiment
A display device according to a fifth embodiment of the present invention will be described with reference to FIGS. 14 to 16B.

[Pixel Configuration of Display Device According to Fifth Embodiment]
FIG. 14 is a schematic cross-sectional view showing a pixel configuration of a display device according to a fifth embodiment of the present invention. 15A to 15B are plan views showing a method of manufacturing a light emitting layer of a display device according to a fifth embodiment of the present invention. 16A to 16B are plan views showing a method of manufacturing a hole transport layer of a display device according to a fifth embodiment of the present invention. In the display device according to the fifth embodiment, as shown in FIG. 14, in plan view, the pixel size of the blue sub-pixel 106B is approximately three times the pixel size of the sub-pixels 106Y, 106R, and 106G of other colors. And has a pixel configuration in which the blue sub-pixels 106B are continuously formed in the same direction (X direction in FIG. 14) in plan view. The cross-sectional structure of the display device according to the present embodiment is the same as that of the fourth embodiment except that the size and the pixel arrangement of the aperture region of the blue sub-pixel 106B are changed. It is a figure corresponded to the cross-section which followed the line in the AA 'line. Since the blue light emitting layer 300 B has a relatively short life as compared with light emitting layers of other colors, the shortening of the life of the entire light emitting element can be prevented by increasing the pixel size of the blue sub-pixel 106 B. Can.

  In the fifth embodiment, as shown in FIG. 14, since the blue sub-pixels 106B are continuously formed in the same direction (X direction in FIG. 14) in plan view, the blue light emitting layer 300R is formed. When forming, as shown in FIG. 15A and FIG. 15B, the light emitting layer 300B in the blue sub-pixel 106B region of the plurality of pixels 106 is collectively formed using a mask 410 having large openings collectively formed in the same direction. be able to. In this case, since the size of the mask opening is large, the yield of mask manufacture is improved. In addition, since the blue light emitting layer 300B is continuously formed in the same direction, it is possible to prevent the occurrence of defects due to color mixing with light emitting layers of other colors when forming the blue light emitting layer 300B.

  In the fifth embodiment, as shown in FIG. 14, the yellow sub-pixel 106Y, the red sub-pixel 106R, and the green sub-pixel 106G adjacent in the same direction (X direction in FIG. 14) in plan view are in this order In the process of separately manufacturing the hole transport layer for adjusting the film thickness, the pixel is shared between the green sub-pixel 106G and the red sub-pixel 106R described in the fourth embodiment. The same mask 420 shown in FIG. 16A is used to form the hole transport layer 220GR and the hole transport layer 220RY shared between the red sub-pixel 106R and the yellow sub-pixel 106Y, as shown in FIG. 16B. Thus, the hole transport layer 220 RY is formed by aligning the opening position of the same mask 420 with the position where the adjacent yellow sub-pixel 106 Y and red sub-pixel 106 R are both opened. After the entire mask 420 is offset moving in the X direction, it can be a hole transport layer 200GR formed continuously together adjacent red subpixel 106R and green sub-pixel 106G in both opening positions. In this case, since the hole transport layer 220RY and the hole transport layer 200GR are films having the same function as the hole transport layer, they are formed of the same film forming material, and therefore, the same mask 420 is offset moved. Each hole transport layer can be continuously formed by

  Also, unlike FIG. 14, the arrangement of the sub-pixels of colors other than blue formed adjacent in the same direction in plan view continues in the order of the green sub-pixel 106G, the red sub-pixel 106R, and the yellow sub-pixel 106Y. Even if formed, the opening position of the mask that opens both the yellow sub-pixel 106Y and the red sub-pixel 106R adjacent to each other, and the red sub-pixel 106R and the green sub-pixel 106G adjacent to each other open Since the relationship with the opening position of the mask is offset in the same direction, in this case as well, as shown in FIG. 16B, the same mask 420 is offset moved in the X direction to form the hole transport layer 220RY. The hole transport layer 200GR can be formed continuously.

  Thus, according to the present embodiment, in the formation process of the hole transport layer 220RY and the formation process of the hole transport layer 220GR, the same mask 420 and the same material for forming the hole transport layer are continuously used. Since the offset film formation can be performed, the manufacturing tact can be shortened, and the cost of the mask and the apparatus used can also be reduced. The other configuration is the same as that of the first to fourth embodiments, and therefore the repetition of the common description will be omitted.

  Those skilled in the art appropriately add, delete, or change the design of components based on the display devices described as the embodiments and examples according to the present invention, or add, omit, or change conditions of processes. Those are included in the scope of the present invention as long as they include the subject matter of the present invention. Moreover, each embodiment mentioned above can be mutually combined in the range which a technical contradiction does not arise.

  In addition, even if other effects or effects different from the effects provided by the aspect of the embodiment described above are apparent from the description of the present specification or the like, or those that can be easily predicted by those skilled in the art, It is naturally understood that the present invention provides.

100: display device (organic EL display device) 102: substrate 104: pixel portion 106: pixel 106B: blue sub-pixel (first sub-pixel) 106G: green sub-pixel (second sub-pixel) 106R: red sub-pixel (third sub-pixel) 106Y, 106Y ': yellow sub-pixel (fourth sub-pixel) 150: organic EL element 170: pixel electrode (anode) 172: organic layer 174: Counter electrode 210: hole injection layer 220c, 220G, 220R, 220Y, 220RY ', 220GR: hole transport layer, 300B, 300G, 300R, 300Y, 300Y': light emitting layer, LA-B, LA-G, LA-R, LA-Y: light emitting area, 410, 420: mask

Claims (17)

One pixel is adjacently arranged on the substrate, a first sub-pixel having a first light emitting area emitting light of a first color independently, and a second light emitting area having a second light emitting area emitting a second color independently Organic EL display device comprising a sub-pixel, a third sub-pixel having a third light-emitting area emitting light independently of the third color, and a fourth sub-pixel having a fourth light-emitting area emitting light independently of the fourth color And
The first to fourth sub-pixels are
First to fourth pixel electrodes provided corresponding to the first to fourth light emitting regions on the substrate;
A counter electrode provided on the first to fourth pixel electrodes;
An organic layer provided between the first to fourth pixel electrodes and the counter electrode;
The organic layer is
A first hole transport layer provided on the first to fourth pixel electrodes;
First to fourth light emitting layers individually provided on the first hole transporting layer according to the first to fourth sub-pixels;
A second hole transport layer provided between the first hole transport layer and the second light emitting layer;
An organic EL display device, comprising: a first hole transport layer; and a third hole transport layer provided between the third light emitting layer and the fourth light emitting layer.   The organic EL display device according to claim 1, wherein the second hole transport layer is individually provided in the second sub-pixel and is not present in the third sub-pixel.   The third sub-pixel has a structure in which the second hole transport layer, the third hole transport layer, and the third light emitting layer are stacked in this order on the first hole transport layer. An organic EL display device according to Item 1. One pixel is adjacently arranged on the substrate, a first sub-pixel having a first light emitting area emitting light of a first color independently, and a second light emitting area having a second light emitting area emitting a second color independently Organic EL display device comprising a sub-pixel, a third sub-pixel having a third light-emitting area emitting light independently of the third color, and a fourth sub-pixel having a fourth light-emitting area emitting light independently of the fourth color And
The first to fourth sub-pixels are
First to fourth pixel electrodes provided corresponding to the first to fourth light emitting regions on the substrate;
A counter electrode provided on the first to fourth pixel electrodes;
An organic layer provided between the first to fourth pixel electrodes and the counter electrode;
The organic layer is
A first hole transport layer provided on the first to fourth pixel electrodes;
A first light emitting layer provided in the first sub pixel on the first hole transport layer;
A second hole transport layer provided in the second sub-pixel on the first hole transport layer;
A second light emitting layer provided in the second sub pixel;
A third hole transport layer provided in the third sub-pixel;
An organic EL display device, comprising: a third light emitting layer provided in the third sub pixel and the fourth sub pixel.   5. The organic EL display device according to claim 4, wherein the second hole transport layer is separately provided in the second sub-pixel and is not present in the third sub-pixel.   The organic EL display device according to claim 4, wherein the third hole transport layer is individually provided in the third sub-pixel and is not present in the fourth sub-pixel.   The organic EL display device according to claim 4, wherein the fourth sub-pixel has a structure in which a fourth hole transport layer and the third light emitting layer are stacked in this order on the first hole transport layer. . The third sub-pixel has a structure in which the second hole transport layer, the third hole transport layer, and the third light emitting layer are stacked in this order on the first hole transport layer,
The organic EL display according to claim 4, wherein the fourth sub-pixel has a structure in which the third hole transport layer and the fourth light emitting layer are stacked in this order on the first hole transport layer. apparatus. Having a plurality of the pixels on the substrate,
The plurality of first sub-pixels are continuously arranged along a first direction on the substrate,
The plurality of second to fourth sub-pixels are arranged in a column adjacent to the first sub-pixel along the first direction, and the second sub-pixel is adjacent to the third sub-pixel, The organic EL display device according to claim 8, wherein the sub-pixels are continuously arranged in the order adjacent to the fourth sub-pixel.   The organic material according to any one of claims 3, 8, and 9, wherein the third hole transport layer is the same layer connecting the adjacent third sub-pixel and the fourth sub-pixel. EL display device.   The organic material according to any one of claims 3, 8, and 9, wherein the second hole transport layer is the same layer connecting the adjacent second sub-pixel and the third sub-pixel. EL display device.   The organic EL display device according to any one of claims 4 to 9, wherein the third light emitting layer is the same layer connecting the adjacent third sub-pixel and the fourth sub-pixel.   The organic EL display device according to any one of claims 1 to 9, wherein film thicknesses of the second hole transport layer and the third hole transport layer are different from each other.   The organic EL display device according to claim 7, wherein film thicknesses of the second hole transport layer, the third hole transport layer, and the fourth hole transport layer are different from one another.   10. The light emitting layer according to any one of claims 1 to 9, wherein the third light emitting layer and the fourth light emitting layer are light emitting layers having peak wavelengths close to each other among the first color to the fourth color. Organic EL display device.   The light emitting layer according to any one of claims 3, 8, and 9, wherein the second light emitting layer and the third light emitting layer are light emitting layers having peak wavelengths close to each other among the first color to the fourth color. The organic EL display device described in one.   The organic EL display device according to claim 9, wherein the first color has the shortest peak wavelength among the first color to the fourth color.

Images