JP2014102976A - Organic electroluminescent display device, and method for manufacturing organic electroluminescent display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent misalignment in separate coloring between each pixel to realize an organic electroluminescent display device, while also realizing high luminance and high picture quality.SOLUTION: An organic electroluminescent display device of the present invention comprises: an element substrate; an undulation part formed on the element substrate and having a height in the vertical direction relative to the top face of the element substrate; and an organic electroluminescent element, the organic electroluminescent display device being characterized in that the undulation part has a plurality of slant faces whose angles relative to the top face of the element substrate are a sharp angle, and that the organic electroluminescent element is formed, out of the top face of the element substrate, on an undulation-to-undulation region which is a region between the undulation parts, and on each of the slant faces.

Description

  The present invention relates to an organic electroluminescence display device and a method for manufacturing the organic electroluminescence display device.

  Organic light emitting diodes, that is, organic electroluminescent elements, are attracting attention as thin and light-emitting sources, and image display devices having a large number of organic electroluminescent elements have been developed. . The organic electroluminescence element has a structure in which at least one organic thin film formed of an organic material is sandwiched between a pixel electrode and a counter electrode.

  An organic electroluminescence display device having an organic electroluminescence element includes, for example, an element substrate in which organic electroluminescence elements are arranged in a matrix corresponding to pixels, and a protective film formed on the organic electroluminescence element. ing. By having such a configuration, light emitted from the organic electroluminescence element is emitted from the element substrate to the protective film and emitted to the outside. Usually, each pixel has a plurality of organic electroluminescence elements that emit light in different colors such as red (R), green (G), and blue (B).

  As a method for manufacturing such an organic electroluminescence display device, a method is disclosed in which a light-emitting layer that emits light of a different color is applied to each pixel using a mask provided with an opening corresponding to each pixel (patent). Reference 1). Also disclosed is a method in which a wall portion having a height in the vertical direction from the element substrate is provided between adjacent pixels, and the light emitting layer is separately applied by vapor deposition (Patent Document 2). According to the method described in Patent Document 2, by adjusting the vapor deposition angle, the shadowed portion of the wall portion and the region other than the portion are separately coated with different types of light emitting layers.

JP-A-8-227276 Japanese Patent Application Laid-Open No. 5-258859

  However, in the method of separately coating the light emitting layer using a mask provided with an opening, the position of the opening may be shifted because the mask expands due to heat. In particular, the smaller the pixel, the smaller the distance between the openings, so that the influence of this positional deviation becomes larger, and the image quality of the image displayed on the organic electroluminescence display device is likely to be affected.

  Further, in the method of separately providing the light emitting layer by providing the wall portion, no light is emitted because no electrode is provided in the region provided with the wall portion, and the luminance is reduced by the amount of the wall portion. Further, when light emitted from the light emitting layer hits the wall portion, a part of the light is absorbed by the wall portion, so that the luminance of the organic electroluminescence display device is lowered. On the other hand, if the area of the wall portion is reduced, the aspect ratio of the wall portion is increased accordingly, and the strength is lowered. Since the wall portion becomes smaller as the pixel becomes smaller, the influence of the strength reduction becomes remarkable. For this reason, a wall part becomes easy to be damaged and it becomes easy to produce the influence on the image quality of the image displayed on an organic electroluminescent display apparatus.

  The present invention has been made in view of such circumstances, and an organic electroluminescence display device capable of realizing high brightness and high image quality while preventing misalignment between the pixels, and An object of the present invention is to provide a method for manufacturing an organic electroluminescence display device.

  (1) An organic electroluminescence display device according to the present invention includes an element substrate, an undulation formed on the element substrate and having a height in a direction perpendicular to the upper surface of the element substrate, an organic electroluminescence element, The undulating portion has a plurality of inclined surfaces with an acute angle with respect to the upper surface of the element substrate, and the organic electroluminescent element is formed between the undulating portions of the upper surface of the element substrate. It is formed on the region between the undulating portions, which is a region between, and on each of the slopes.

  (2) In the organic electroluminescence display device of the present invention, in (1), the plurality of inclined surfaces are different from the first direction and the first inclined surface perpendicular to the first direction. A second slope that is perpendicular to the second direction, and the organic electroluminescence element is formed on the first lower electrode and the first lower electrode formed on the first slope. A first light emitting layer; a second lower electrode formed on the second slope; a second light emitting layer formed on the second lower electrode; and a third lower electrode formed on the region between the undulations And a third light emitting layer formed on the third lower electrode, and the first light emitting layer, the second light emitting layer, and the third light emitting layer may emit light in different colors.

  (3) The organic electroluminescence display device according to the present invention is the organic electroluminescence display device according to (2), wherein the first bank formed in the boundary between the first slope and the upper surface of the element substrate and protruding in the vertical direction, and the second slope The vertical direction from the upper surface of the element substrate located between the first bank and the second inclined surface, the second bank protruding in the vertical direction formed at the boundary between the upper surface of the element substrate and the upper surface of the element substrate And a third bank that protrudes in the vertical direction and is formed on the top of the undulating portion that is the largest region of the undulating portion.

  (4) In the method for manufacturing an organic electroluminescence display device of the present invention, undulations having a plurality of inclined surfaces with an acute angle with respect to the upper surface of the element substrate are formed on the element substrate at intervals. And forming an organic electroluminescence element on the region between the undulating portions that is a region between the undulating portions of the upper surface of the element substrate and on each of the slopes, and In the step of forming the undulation portion, the step of forming the first slope and the second slope facing the direction different from the first slope and forming the organic electroluminescence element includes the first slope and the second slope. A first lower electrode, a second lower electrode, and a third lower electrode are formed on the slope and the region between the undulating portions, respectively, and the first emission is formed on the first lower electrode by vapor deposition from the first vapor deposition direction. A first vapor deposition step of sequentially forming a layer and a hole blocking layer; a second vapor deposition step of forming a second light emitting layer on the second lower electrode by vapor deposition from a second vapor deposition direction; and a third vapor deposition direction. Forming a third light emitting layer on the third lower electrode by vapor deposition from, and forming an upper electrode on the first light emitting layer, the second light emitting layer, and the third light emitting layer. An angle formed between the third vapor deposition direction and the vertical direction of the element substrate is smaller than an angle formed between the first vapor deposition direction and the vertical direction, and the first light emitting layer and the second light emitting layer. The light emitting layer and the third light emitting layer emit light in different colors.

  In the organic electroluminescence display device according to the present invention, organic electroluminescence elements are formed on each slope of the undulating portion and on the region between the undulating portions. For this reason, compared with the organic electroluminescent display apparatus which does not have such a structure, the area of the area | region in which an organic electroluminescent element is provided becomes large, and a brightness | luminance improves. Moreover, since the current density of the unit area in the light emitting layer for obtaining a certain luminance can be reduced, the life of the organic electroluminescence display device is improved. In addition, since the organic electroluminescence elements are formed on the slopes of the undulations and on the regions between the undulations, the organic electroluminescence elements between the pixels are compared with the organic electroluminescence display device that does not have such a configuration. It is difficult for position shift to occur. Furthermore, since the angle of the slope of the undulating portion is an acute angle with respect to the upper surface of the element substrate, the aspect ratio of the undulating portion can be kept small. For this reason, compared with the organic electroluminescent display device which has a wall part, even if it makes a pixel small, the intensity | strength fall of an uneven | corrugated part is suppressed. For this reason, breakage of the undulating portion can be prevented, and deterioration of the image quality of the image displayed on the organic electroluminescence display device can be suppressed.

FIG. 1 is a schematic plan view of an organic electroluminescence display device according to an embodiment of the present invention. FIG. 2 is a schematic sectional view taken along the line II-II of the organic electroluminescence display device shown in FIG. FIG. 3 is a partial enlarged view of region III of the organic electroluminescence display device shown in FIG. FIG. 4 is a partially enlarged view of a region corresponding to region III of the organic electroluminescence display device according to the second embodiment. FIG. 5 is a partially enlarged view of a region corresponding to region III, showing a method for manufacturing an organic electroluminescence display device according to an embodiment of the present invention. FIG. 6 is a partial enlarged view of a region corresponding to region III, showing a method for manufacturing an organic electroluminescence display device according to an embodiment of the present invention. FIG. 7 is a partially enlarged view of a region corresponding to region III, showing a method for manufacturing an organic electroluminescence display device according to an embodiment of the present invention. FIG. 8 is a partially enlarged view of a region corresponding to region III, showing a method for manufacturing an organic electroluminescence display device according to an embodiment of the present invention. FIG. 9 is a partial enlarged view of a region corresponding to region III, showing a method for manufacturing an organic electroluminescence display device according to an embodiment of the present invention. FIG. 10 is a partially enlarged view of a region corresponding to region III, showing a method for manufacturing an organic electroluminescence display device according to an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Components having the same function among the components appearing in the specification are denoted by the same reference numerals, and the description thereof is omitted. Note that the drawings referred to in the following description may show the features that are enlarged for convenience in order to make the features easier to understand, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent. In addition, the materials and the like exemplified in the following description are examples, and each component may be different from them, and can be changed and implemented without changing the gist thereof.

  First, an organic electroluminescence display device 1 according to an embodiment (first embodiment) of the present invention will be described. FIG. 1 is a schematic plan view of an organic electroluminescence display device 1 according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view taken along the line II-II of the organic electroluminescence display device 1 shown in FIG. An organic electroluminescence display device 1 according to the present embodiment includes an element substrate 10, a flexible circuit board 2, a drive driver 3, an organic electroluminescence element 30 provided on the element substrate 10, a sealing film 40, And a protective film 50.

  The element substrate 10 in the present embodiment is composed of, for example, a substrate 10a and a drive region 10b. The substrate 10a is a substrate on which, for example, a rectangular low-temperature polysilicon layer is formed. Here, “low temperature polysilicon” refers to polysilicon formed under conditions of 600 ° C. or less.

Of the top surface 10a ₁ of the substrate 10a, in a region where the drive region 10b is not formed, the flexible circuit board 2 is connected, further, driver 3 is provided. The drive driver 3 is a driver to which image data is supplied from the outside of the organic electroluminescence display device 1 via the flexible circuit board 2. The drive driver 3 is supplied with image data, thereby supplying display data to the organic electroluminescence element 30 via a data line (not shown).

  The drive region 10b is a region where a transistor (not shown) formed on the substrate 10a is formed. This transistor is a transistor for driving the organic electroluminescence element 30, and is provided on the substrate 10a for each pixel P. This transistor can adopt a known configuration, and specifically includes, for example, a gate electrode, a source / drain electrode, an interlayer insulating film, and the like (not shown). The upper surface of the transistor is covered with a passivation layer made of an insulator, and the upper surface constitutes the upper surface 10c of the element substrate 10 (drive region 10b).

  Note that the configuration of the element substrate 10 is not limited to the examples given here, and other configurations are possible as long as the organic electroluminescence element 30 can be driven and the upper surface 10c is flat and has an insulating property. Also good.

  The organic electroluminescence element 30 is provided on the element substrate 10. The organic electroluminescence element 30 is provided in a display area D having an outer periphery smaller than the element substrate 10 in a plan view, for example, and a black matrix BM made of, for example, a light-impermeable film is disposed in the outer area. Yes.

  FIG. 3 is a partial enlarged view of region III of the organic electroluminescence display device 1 shown in FIG. This III region is a region corresponding to the four pixels P in the display region D. On the element substrate 10 in the III region, the undulating portion 12, the organic electroluminescence element 30, the sealing film 40, and the protective film 50 are laminated.

  The undulating portion 12 is made of an insulator and is formed on the element substrate 10 according to each pixel P. The undulating portion 12 extends in one direction, and the undulating portion 12 shown in FIG. 3 shows a state cut by a cutting line perpendicular to the extending direction. The length of the undulating portion 12 in the extending direction may be set as appropriate according to the size of the desired pixel P.

The undulating portion 12 has a plurality of inclined surfaces whose cross-sectional shape is, for example, a triangle and whose angles with respect to the upper surface 10c of the element substrate 10 are acute angles. Undulations 12 in the present embodiment, for example, has a first inclined surface 12a is an angle with respect to the upper surface 10c is theta _g, the angle of the upper surface 10c of the second inclined surface 12b is theta _r .

The first inclined surface 12a is perpendicular to the first direction A having an angle with respect to the upper surface 10c of 90 ° −θ _g , and the second inclined surface 12b has an angle of 90 ° with respect to the upper surface 10c. It is perpendicular to the second direction B, which is −θ _r . Further, the second direction B indicates a direction different from the first direction A.

  Assuming that the direction perpendicular to the upper surface 10c of the element substrate 10 is the vertical direction V, the undulating portion upper portion 12c is a region having the largest distance (height h) in the vertical direction V from the upper surface 10c. The shape of the undulating portion upper portion 12c includes not only a ridge shape having no flat surface as shown in FIG. 3, but also a shape that deviates from the ridge shape in the range of error due to the manufacturing process. Further, the cross-sectional shape of the undulating portion 12 is preferably a triangle as shown in FIG. 3, but may be a trapezoid whose upper side is smaller than the lower side. The height h can be set to, for example, 10 μm to 100 μm, but may be set as appropriate according to the width of the pixel P.

  Adjacent undulations 12 are provided with a space therebetween. A region between the undulating portions 12 in the upper surface 10 c of the element substrate 10 is defined as a region 13 between the undulating portions. The region 13 between the undulating portions in the present embodiment indicates a region that is not covered by the undulating portion 12 in the upper surface 10 c of the element substrate 10.

  The first slope 12a, the second slope 12b, and the region 13 between the undulating parts are formed in a matrix so as to correspond to each pixel P.

  The organic electroluminescent element 30 includes, for example, a first organic electroluminescent element 30G having a first light emitting layer 17G that emits green light, a second organic electroluminescent element 30R having a second light emitting layer 17R that emits red light, and blue. And a third organic electroluminescence element 30B having a third light emitting layer 17B that emits light. The emission colors of the first light emitting layer 17G, the second light emitting layer 17R, and the third light emitting layer 17B are not limited to the examples given here, and may be other colors. In addition, the first light emitting layer 17G, the second light emitting layer 17R, and the third light emitting layer 17B are not limited to those that emit light in different colors, and two or all three of these three types emit light in the same color. It may be a thing.

  The first organic electroluminescent element 30G is formed on the first inclined surface 12a, the second organic electroluminescent element 30R is formed on the second inclined surface 12b, and the third organic electroluminescent element 30B is formed on the undulation region 13. ing.

  Among these, the structure of the 1st organic electroluminescent element 30G is demonstrated. The first organic electroluminescence element 30G includes, for example, a first lower electrode 15G, an organic layer 20 including a first light emitting layer 17G, and an upper electrode 19.

  The first lower electrode 15G is formed on the first slope 12a of the undulating portion 12. The first lower electrode 15G is made of, for example, a metal such as Ag, but the material is not limited to Ag, and other materials may be used. The first lower electrode 15G is electrically connected to a transistor (not shown) through a contact hole (not shown) provided in the drive region 10b. With such a configuration, the drive current supplied from the transistor is injected into the first light emitting layer 17G via the first lower electrode 15G.

  The organic layer 20 is formed on the first lower electrode 15G. The organic layer 20 is formed, for example, by laminating a hole transport layer 16, a first light emitting layer 17G, and a hole block layer 18 in order from the first lower electrode 15G side. The stacked structure of the organic layer 20 is not limited to the structure described here, and the structure is not specified as long as it includes at least the first light emitting layer 17G.

  The hole transport layer 16 is formed so as to cover the first lower electrode 15G and the first inclined surface 12a. The hole transport layer 16 in this embodiment is in contact with the first lower electrode 15G, the second lower electrode 15R, and the third lower electrode 15B in common. The hole transport layer 16 located on the first lower electrode 15G has a function of transporting holes (holes) injected from the first lower electrode 15G to the first light emitting layer 17G.

  The first light emitting layer 17G in the present embodiment is formed on the first lower electrode 15G via the hole transport layer 16. The first light emitting layer 17G is made of, for example, an organic electroluminescent material that emits green light by combining holes and electrons. Note that the emission color of the first light-emitting layer 17G is not limited to green, and may emit white light or other colors.

  A hole blocking layer 18 is formed on the first light emitting layer 17G. The hole blocking layer 18 has a function of blocking holes injected from the first lower electrode 15G.

  The third light emitting layer 17B may be formed on the organic layer 20 of the first organic electroluminescence element 30G in the present embodiment. The third light emitting layer 17B is, for example, a light emitting layer that emits light with a color different from that of the first light emitting layer 17G. Even in such a configuration, since the hole blocking layer 18 is formed between the first light emitting layer 17G and the third light emitting layer 17B, the holes injected from the first lower electrode 15G are not blocked by the hole blocking layer 18. Is blocked. For this reason, transport of holes to the third light emitting layer 17B formed on the hole blocking layer 18 is prevented, and the third light emitting layer 17B on the first light emitting layer 17G does not emit light.

  The upper electrode 19 is formed on the organic layer 20 (on the first light emitting layer 17G). In addition, since the hole block layer 18 and the 3rd light emitting layer 17B are formed on the organic layer 20 of the 1st organic electroluminescent element 30G in this embodiment, the upper electrode 19 is on the 3rd light emitting layer 17B. It is formed to cover.

  The upper electrode 19 is a transparent common electrode that is in common contact with the organic layer 20 of the plurality of organic electroluminescence elements 30 (first, second, and third organic electroluminescence elements 30G, 30R, and 30B). The upper electrode 19 is made of a material having translucency and conductivity, such as ITO.

  Next, the configuration of the second organic electroluminescence element 30R will be described. The second organic electroluminescent element 30R includes a second lower electrode 15R, an organic layer 20 including the second light emitting layer 17R, and an upper electrode 19. The second organic electroluminescent element 30R is configured such that the second lower electrode 15R is formed on the second inclined surface 12b, the second light emitting layer 17R emits red light, for example, and the hole blocking layer 18 is formed. This is different from the first organic electroluminescence element 30G in that it is not performed. Hereinafter, the description of the same configuration as that of the first organic electroluminescence element 30G is omitted.

  The second lower electrode 15R is formed on the second slope 12b of the undulating portion 12. On the second lower electrode 15R, an organic layer 20 formed by laminating the hole transport layer 16 and the second light emitting layer 17R is formed. The second light emitting layer 17R is a light emitting layer that emits red light, for example. Note that the emission color of the second light emitting layer 17R is not limited to red, and may emit white light or other colors. An upper electrode 19 is formed on the organic layer 20 (on the second light emitting layer 17R).

  Next, the configuration of the third organic electroluminescence element 30B will be described. The third organic electroluminescence element 30B includes, for example, a third lower electrode 15B, an organic layer 20 including the third light emitting layer 17B, and an upper electrode 19. The configuration of the third organic electroluminescence element 30B is such that the third lower electrode 15B is formed on the undulating region 13 (upper surface 10c), the third light emitting layer 17B emits blue light, for example, The point from which the hole block layer 18 is not formed differs from the 1st organic electroluminescent element 30G. Hereinafter, the description of the same configuration as that of the first organic electroluminescence element 30G is omitted.

  The third lower electrode 15B is formed on the region 13 between the undulations. On the third lower electrode 15B, an organic layer 20 formed by laminating a hole transport layer 16 and a third light emitting layer 17B is formed. The third light emitting layer 17B is, for example, a light emitting layer that emits blue light. Note that the emission color of the third light emitting layer 17B is not limited to blue, and may emit white light or other colors. An upper electrode 19 is formed on the organic layer 20 (on the third light emitting layer 17B).

  Each organic electroluminescence element 30 (first, second, and third organic electroluminescence elements 30G, 30R, and 30B) is covered with a sealing film 40. The sealing film 40 is made of, for example, SiN, SiO, SiON, resin, or the like, and may be a single layer film made of these materials or a laminated structure.

  The protective film 50 is disposed on the sealing film 40. As long as the protective film 50 protects the surface of the sealing film 40, its configuration and material are not limited, and a known film may be used. Further, instead of the protective film 50, for example, a substrate made of a translucent material such as glass, quartz, or plastic may be disposed on the sealing film 40.

  In the organic electroluminescence display device 1 according to this embodiment, the organic electroluminescence elements 30 (first, second, and second) are respectively formed on the first inclined surface 12a, the second inclined surface 12b, and the region 13 between the undulating portions. 3 organic electroluminescence elements 30G, 30R, 30B) are formed. For this reason, compared with the organic electroluminescent display apparatus which does not have such a structure, the area of the area | region in which the organic electroluminescent element 30 is provided becomes large, and a brightness | luminance improves. Moreover, since the current density of the unit area in the light emitting layer for obtaining a certain luminance can be reduced, the life of the organic electroluminescence display device 1 is improved.

  In addition, since the organic electroluminescence elements 30 are formed on the first slope 12a and the second slope 12b of the undulating portion 12 provided according to each pixel P, and on the region 13 between the undulating portions, respectively. Compared to an organic electroluminescence display device that does not have such a configuration, the organic electroluminescence element 30 is less likely to be misaligned between the pixels P.

  Further, when the organic electroluminescence elements 30 formed on the first inclined surface 12a and the second inclined surface 12b emit light, light emitted obliquely from the first inclined surface 12a and the second inclined surface 12b is converted into an organic electroluminescence display device. Proceed in the front direction (vertical direction V) of 1. For this reason, at least any one of the layer which comprises the organic layer 20 of the organic electroluminescent element 30, the sealing film 40, and the protective film 50 has a film | membrane structure from which the luminance peak becomes a diagonal direction with respect to a film surface. Thereby, the brightness | luminance of the front direction of the organic electroluminescent display apparatus 1 can be improved.

Furthermore, since the angle θ _g formed between the first inclined surface 12a and the upper surface 10c of the undulating portion 12 and the angle θ _r formed between the second inclined surface 12b and the upper surface 10c are acute angles, the aspect ratio of the undulating portion 12, that is, the undulating portion The ratio of the height h to the width of the bottom surface of 12 is kept small. For this reason, compared with the organic electroluminescent display apparatus which has a wall part, even if the pixel P is made small, the strength reduction of the undulating part 12 is suppressed. For this reason, breakage of the undulating portion 12 is prevented, and deterioration of the image quality of the image displayed on the organic electroluminescence display device 1 can be suppressed.

  In the organic electroluminescence display device 1 according to the present embodiment, the first lower electrode 15G and the first light emitting layer 17G are formed on the first inclined surface 12a, and the second lower electrode 15R and the second light emitting are formed on the second inclined surface 12b. The layer 17R is formed, and the third lower electrode 15B and the third light emitting layer 17B are formed on the region 13 between the undulations. The first light emitting layer 17G, the second light emitting layer 17R, and the third light emitting layer 17B have different colors. By emitting light at, the pixel P can be miniaturized and color mixing can be prevented as compared with an organic electroluminescence display device that does not have such a configuration. For this reason, the image quality of the image displayed on the organic electroluminescence display device 1 can be improved.

  Next, the organic electroluminescence display device 1 according to the second embodiment will be described. FIG. 4 is a partially enlarged view of a region corresponding to the region III of the organic electroluminescence display device 1 according to the second embodiment. The organic electroluminescence display device 1 according to the second embodiment is different from the organic electroluminescence display device 1 according to the first embodiment in that the bank 14 is provided. Hereinafter, the configuration related to the bank 14 will be described, and the description of the configuration similar to that of the organic electroluminescence display device 1 according to the first embodiment will be omitted.

The organic electroluminescent display device 1 according to the second embodiment is formed in the boundary 10c ₁ of the upper surface 10c of the first inclined surface 12a and the element substrate 10, bank 14 projecting in the vertical direction V (the first bank 14a) , which is formed at the boundary 10c ₂ of the second inclined surface 12b and the upper surface 10c, a bank 14 projecting in the vertical direction V (second bank 14b), formed in undulations upper 12c, bank projecting vertically V 14 (Third bank 14c).

  The height of the bank 14 in the vertical direction V may be such that the upper end 14 t of the bank 14 is located below the upper surface of the upper electrode 19. The upper end 14t is preferably located closer to the boundary between the upper electrode 19 and the organic layer 20. Further, the width of the bank 14 may be appropriately set according to the size of the pixel P and the width of the undulating portion upper portion 12c.

Since the organic electroluminescence display device 1 according to the present embodiment has the above-described configuration, the light emitting layers of different colors overlap each other at the boundaries 10c ₁ and 10c ₂ that are the boundaries between adjacent pixels P and the undulating portion upper portion 12c. Is prevented. For this reason, color mixing of adjacent pixels P can be prevented, and the image quality of the image displayed on the organic electroluminescence display device 1 can be improved.

  Next, a method for manufacturing the organic electroluminescence display device 1 according to an embodiment of the present invention will be described with reference to the drawings. 5 to 10 are partial enlarged views of a region corresponding to region III, showing a method for manufacturing an organic electroluminescence display device according to an embodiment of the present invention.

  The manufacturing method of the organic electroluminescence display device 1 according to the present embodiment includes a step of forming the element substrate 10 and a plurality of inclined surfaces (first steps) on the element substrate 10 and having an acute angle with respect to the upper surface 10c of the element substrate 10. A step of forming a plurality of undulating portions 12 having one inclined surface 12a and a second inclined surface 12b) at an interval from each other, and an organic electroluminescence element 30 on each inclined surface (first inclined surface 12a, second inclined surface 12b), And a step of forming each on the region 13 between the undulating portions which is a region between the undulating portions 12 of the upper surface 10c of the element substrate 10.

  First, the element substrate 10 is formed. First, a substrate 10a, for example, a rectangular low-temperature polysilicon substrate is prepared. Next, a driving region 10b having a flat upper surface 10c having a transistor (not shown) is formed on the substrate 10a. Thereby, the element substrate 10 is formed.

  Next, as shown in FIG. 5, for example, by photolithography, the first inclined surface 12 a having an acute angle with respect to the upper surface 10 c and the second inclined surface 12 b facing in a direction different from the first inclined surface 12 a are provided. The undulating portion 12 made of an insulator is formed on the element substrate 10 according to the pixel P. The method of forming the undulating portion 12 is not limited to photolithography, and nanoimprinting is possible as long as the undulating portion 12 having a plurality of inclined surfaces with an acute angle with respect to the upper surface 10c of the element substrate 10 can be formed. Other methods may be used.

  As shown in FIG. 5, the undulating portion 12 is preferably formed so that the cross-sectional shape thereof is a triangular shape, but may be formed so that the upper side has a trapezoidal shape smaller than the lower side. Further, the height in the V direction of the undulating portion upper portion 12c can be set to, for example, 10 μm to 100 μm, but may be appropriately set according to the width of the pixel P.

Banks (not shown) may be formed on the boundary 10c ₁ between the first inclined surface 12a and the upper surface 10c of the element substrate 10, the boundary 10c ₂ between the second inclined surface 12b and the upper surface 10c, and the undulating portion upper portion 12c. The height in the vertical direction V of the bank may be appropriately set according to the height in the V direction of the organic electroluminescence element 30 described later. Further, the bank width may be appropriately set according to the size of the pixel P and the width of the undulating portion upper portion 12c.

  Next, the organic electroluminescence element 30 is placed on each inclined surface (first inclined surface 12a, second inclined surface 12b), which is a region between the undulating portions 12 of the upper surface 10c of the element substrate 10, and on the region 13 between the undulating portions. Form each one. The step of forming the organic electroluminescence element 30 includes the step of forming the lower electrode (first lower electrode 15G, second lower electrode 15R, third lower electrode 15B), the step of forming the organic layer 20, and the upper electrode 19 Forming the step.

  First, as shown in FIG. 6, lower electrodes are formed on the first slope 12a, the second slope 12b, and the region 13 between the undulations. Of these lower electrodes, those formed on the first inclined surface 12a are formed on the first lower electrode 15G, those formed on the second inclined surface 12b are formed on the second lower electrode 15R, and the region 13 between the undulations. 3 Lower electrode 15B. The first lower electrode 15G, the second lower electrode 15R, and the third lower electrode 15B are electrically connected to a transistor (not shown) in the drive region 10b.

  Next, the organic layer 20 is formed. The step of forming the organic layer 20 further includes the step of forming the hole transport layer 16 and the first light emitting layer 17G and the hole blocking layer 18 in order on the first lower electrode 15G by vapor deposition from the first vapor deposition direction G. By the first vapor deposition step to be formed, the second vapor deposition step of forming the second light emitting layer 17R on the second lower electrode 15R by vapor deposition from the second vapor deposition direction R, and the vapor deposition from the third vapor deposition direction B And a third vapor deposition step of forming the third light emitting layer 17B on the third lower electrode 15B.

  First, as shown in FIG. 7, the first slope 12a, the second slope 12b, and the region 13 between the undulations, and the first lower electrode 15G, the second lower electrode 15R, and the third lower electrode 15B are covered. Then, the hole transport layer 16 is formed.

Next, the first vapor deposition step will be described. First, as shown in FIG. 8, a first light emitting layer 17G and a hole blocking layer 18 are sequentially formed in a region on the first lower electrode 15G by oblique vapor deposition from the first vapor deposition direction G. The angle between the first deposition direction G and the vertical direction V and the angle theta _1, the width of the first inclined surface 12a WG in the extending direction of the undulations 12 relative to a direction perpendicular is W, the width of the second inclined surface 12b WR When the width of the region 13 between the undulating parts is WB and the height of the undulating part 12 is h, the angle θ _{1 is set} to tan ⁻¹ ((WR + WB) / h) or more, thereby the second slope 12b The deposited material does not adhere to the hole transport layer 16 and the hole transport layer 16 on the region 13 between the undulations. This is because the oblique deposition on the second slope 12b and the region corresponding to the region 13 between the undulations is blocked by the first slope 12a.

By setting the angle θ ₁ of the first vapor deposition direction G in this way, the first light emitting layer 17G and the hole blocking layer 18 are regions on the hole transport layer 16 corresponding to the first inclined surface 12a (first lower portion). Selectively on the electrode 15G).

Next, the second vapor deposition step will be described. First, as shown in FIG. 9, the second light emitting layer 17R that emits light in a color different from that of the first light emitting layer 17G is formed in the region on the second lower electrode 15R by oblique vapor deposition from the second vapor deposition direction R. To do. When the angle between the deposition direction and the vertical direction V and the angle theta _2, by setting the angle theta ₂ to ^{tan -1 ((WG + WB)} / h) or more, the hole transport layer on the first slope 12a 16 Further, the deposition object does not adhere to the hole transport layer 16 on the region 13 between the undulations. This is because the oblique deposition on the first slope 12a and the region corresponding to the region 13 between the undulating portions is blocked by the second slope 12b.

By setting the angle θ ₂ of the second vapor deposition direction R in this way, the second light emitting layer 17R is placed in a region (on the second lower electrode 15R) corresponding to the second inclined surface 12b on the hole transport layer 16. Selectively formed.

Next, the third vapor deposition step will be described. First, as shown in FIG. 10, light is emitted in a color different from that of the first light emitting layer 17G and the second light emitting layer 17R in the region on the third lower electrode 15B by oblique vapor deposition from the third vapor deposition direction B. A third light emitting layer 17B is formed. When the angle formed by the third deposition direction B and the vertical direction V and the angle theta _3, the angle ^{_{θ 3 tan -1 (WR / h}} ) or more, ^{and, tan -1 (WR + WB /} h) setting below Thus, the deposition object does not adhere to the second light emitting layer 17R on the second inclined surface 12b. This is because the oblique deposition on the region corresponding to the second slope 12b is blocked by the first slope 12a.

By setting the angle θ ₃ in the third vapor deposition direction B in this way, the third light emitting layer 17B is a region on the hole transport layer 16 corresponding to the region 13 between the undulating portions (on the third lower electrode 15B). Selectively formed.

Note that by a third deposition direction B is the angle theta ₃ formed by the vertical direction V, the first deposition direction G is smaller than the angle theta ₁ which forms a vertical direction V, the region corresponding to the first inclined surface 12a Also deposits adhere to. However, since the first light emitting layer 17G is covered with the hole blocking layer 18, holes injected from the first lower electrode 15G are blocked in the hole blocking layer 18. For this reason, even if the organic electroluminescence element 30 is driven, the transport of holes to the third light emitting layer 17B on the hole blocking layer 18 is prevented, and the third light emitting layer 17B on the first light emitting layer 17G emits light. There is nothing.

  Next, the upper electrode 19 is formed so as to cover the organic layer 20. Thus, the organic electroluminescence element 30 shown in FIG. 3 is formed. Then, the sealing film 40 which covers each organic electroluminescent element 30 is formed, and the organic electroluminescent display apparatus 1 shown in FIG. 3 is manufactured by forming the protective film 50 which covers the sealing film 40.

In the manufacturing method of the organic electroluminescence display device 1 in the present embodiment, the first light emitting layer 17G and the hole blocking layer 18 are formed on the first inclined surface 12a by vapor deposition from the first vapor deposition direction G, and the second vapor deposition direction. the second light-emitting layer 17R is formed by deposition from R on the second slope 12b, and the second light-emitting layer 17R is formed on the second inclined surface 12b by vapor deposition from the second deposition direction R, the angle theta ₃ angle by less than theta _1, without providing a wall portion and a black matrix between pixels P, in a region corresponding to each pixel P, it can be separately applied a plurality of types of light emitting layers that emit light in different colors. For this reason, compared with the manufacturing method of the organic electroluminescent display apparatus 1 which does not have this structure, even if it refines | miniaturizes the pixel P, a light emitting layer can be correctly painted separately. Thereby, the organic electroluminescence display device 1 capable of displaying a high-quality image can be provided.

  In addition, the manufacturing method in the present embodiment can provide the organic electroluminescence display device 1 having a high luminance and a long lifetime as compared with the manufacturing method of the organic electroluminescence display device in which the wall portion is provided between the pixels P. . In addition, the manufacturing method according to the present embodiment forms the undulating portion 12 having an inclined surface with an acute angle with respect to the upper surface 10c according to the region of the pixel P. 12 is suppressed. Therefore, it is possible to provide the organic electroluminescence display device 1 that can suppress the breakage of the undulating portion 12 and the image quality degradation caused thereby.

  As mentioned above, although embodiment of this invention was described, this invention is not restricted to embodiment mentioned above. For example, the configuration described in the above-described embodiment may be replaced by a configuration that has substantially the same configuration, a configuration that exhibits the same operational effects, or a configuration that can achieve the same purpose.

  For example, a reflective film (not shown) is provided between the first slope 12a and the first lower electrode 15G, between the second slope 12b and the second lower electrode 15R, and between the undulating region 13 and the third lower electrode 15B. It may be. The reflective film is provided to reflect the light emitted from the organic electroluminescence element 30 toward the sealing film 40 side. Such a reflective film is preferably as the light reflectance is high. For example, a metal film made of aluminum, silver, or the like can be used.

1 the organic electroluminescent display device, 2 a flexible circuit board, 3 driver, 10 device substrate, 10a substrate, 10b drive region, 10c upper _surface, 10c 1, 10c ₂ boundary, 12 undulations, 12a first slope, 12b second inclined surface 12c Upper part of undulation part, 13 Region between undulation part, 14 bank, 14a 1st bank, 14b 2nd bank, 14c 3rd bank, 15G 1st lower electrode, 15R 2nd lower electrode, 15B 3rd lower electrode, 16 holes Transport layer, 17G first light-emitting layer, 17R second light-emitting layer, 17B third light-emitting layer, 18 hole blocking layer, 19 upper electrode, 20 organic layer, 30 organic electroluminescent device, 30G first organic electroluminescent device, 30R first 2 organic electroluminescence elements, 30B 3rd organic electroluminescence 40, sealing film, 50 protective film, A first direction, B second direction, G first vapor deposition direction, R second vapor deposition direction, B third vapor deposition direction, h height, V Vertical direction, θ _g , θ _r angle, θ ₁ , θ ₂ , θ ₃ angle, WG, WR, WB width.

Claims (4)

An element substrate;
An undulation formed on the element substrate and having a height in a direction perpendicular to the upper surface of the element substrate;
An organic electroluminescence element,
The undulating portion has a plurality of inclined surfaces with an acute angle with respect to the upper surface of the element substrate;
The organic electroluminescence display device, wherein the organic electroluminescence element is formed on a region between undulations that is a region between the undulations on the upper surface of the element substrate and on each of the inclined surfaces. . The organic electroluminescence display device according to claim 1,
The plurality of slopes are
A first slope that is perpendicular to the first direction;
A second slope that is perpendicular to a second direction that is different from the first direction;
The organic electroluminescence element is
A first lower electrode formed on the first slope and a first light emitting layer formed on the first lower electrode;
A second lower electrode formed on the second slope and a second light emitting layer formed on the second lower electrode;
A third lower electrode formed on the region between the undulations and a third light emitting layer formed on the third lower electrode;
Have
The first light-emitting layer, the second light-emitting layer and the third light-emitting layer emit light in different colors,
An organic electroluminescence display device. The organic electroluminescence display device according to claim 2,
A first bank protruding in the vertical direction and formed at a boundary between the first slope and the upper surface of the element substrate;
A second bank protruding in the vertical direction and formed at a boundary between the second slope and the upper surface of the element substrate;
The vertical direction, which is formed between the first slope and the second slope, is formed on an upper portion of the undulating portion, which is the largest region of the undulating portion, in the vertical direction from the upper surface of the element substrate. A third bank protruding into
An organic electroluminescence display device comprising: On the element substrate, forming undulations having a plurality of inclined surfaces with an acute angle with respect to the upper surface of the element substrate, spaced apart from each other;
Forming an organic electroluminescent element on the region between the undulating portions, which is a region between the undulating portions of the upper surface of the element substrate, and on each of the inclined surfaces;
Have
In the step of forming the undulations,
Forming a first slope and a second slope facing in a different direction from the first slope;
Forming the organic electroluminescence element,
Forming a first lower electrode, a second lower electrode, and a third lower electrode on the first slope, the second slope, and the region between the undulations, respectively;
A first vapor deposition step of sequentially forming a first light emitting layer and a hole blocking layer on the first lower electrode by vapor deposition from a first vapor deposition direction;
A second vapor deposition step of forming a second light emitting layer on the second lower electrode by vapor deposition from a second vapor deposition direction;
A third vapor deposition step of forming a third light emitting layer on the third lower electrode by vapor deposition from a third vapor deposition direction;
Forming an upper electrode on the first light emitting layer, the second light emitting layer, and the third light emitting layer,
The angle formed by the third deposition direction with the vertical direction of the element substrate is smaller than the angle formed by the first deposition direction with the vertical direction.
The method of manufacturing an organic electroluminescence display device, wherein the first light emitting layer, the second light emitting layer, and the third light emitting layer emit light in different colors.

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