JP2004014447A - Display device and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device with a simple structure improvable in luminescence unevenness, and to provide a manufacturing method therefor. <P>SOLUTION: In this display device, a drive circuit substrate 20 is oppositely disposed on the side of organic luminescent elements 10R, 10G and 10B of a display panel 10. An insulation layer 15 covering the organic luminescence elements 10R, 10G and 10B is formed with a first opening 15A and a second opening 15B in each of the organic luminescence elements 10R, 10G and 10B. The first opening 15A and the second opening 15B are filled and formed with a first electroconductive connection part 16A and a second electroconductive connection part 16B. The first electroconductive connection part 16A directly electrically connects a first connection part 21A of the drive circuit substrate 20 and a transparent electrode 12, while the second electroconductive connection part 16B directly electrically connects a second connection part 21B of the drive circuit substrate 20 and a back electrode 14. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a display device including a plurality of organic light emitting elements (organic EL (Electroluminescence) elements) and a method of manufacturing the same.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, display devices (displays) using self-luminous elements such as light-emitting diodes (LEDs), laser diodes (LDs), and organic light-emitting elements have been developed. Generally, this type of display device has a screen section (display panel) formed by arranging a plurality of self-luminous elements in a matrix, and selectively emits light in accordance with a video signal to display an image. Done.
[0003]
A display device using a self-luminous element has an advantage that a backlight is not required as compared with a non-self-luminous display device such as a liquid crystal display (LCD). In particular, a display device (organic EL display) using an organic light-emitting element has attracted attention in recent years because of its wide viewing angle, high visibility, and high response speed of the element.
[0004]
The organic light emitting element has, for example, a structure in which a transparent electrode, an organic layer including a light emitting layer, and a back electrode are sequentially stacked on a transparent substrate, and light generated in the light emitting layer is emitted from the transparent substrate side. Taken out. As an organic EL display using such an organic light emitting element, an active matrix in which active elements such as thin film transistors (TFTs) are formed on a transparent substrate and each organic light emitting element is independently driven by these active elements. Although there is a type, a passive matrix type in which a transparent electrode and a back electrode are formed in a stripe shape crossing each other and an organic light emitting element is arranged at the intersection thereof can be manufactured at a low cost with few manufacturing steps.
[0005]
[Problems to be solved by the invention]
In recent years, with the increase in the number of pixels for miniaturization or enlargement of the screen, the passive matrix type has a problem in that the stripes of the transparent electrode and the back electrode become thin and long, and the resistance value increases. . Conventionally, a drive circuit is connected to the ends of the transparent electrode and the back electrode by using a printed wiring or the like. A difference occurs in the flowing current value, which causes uneven light emission.
[0006]
Further, as the width of the stripe is reduced, it has been difficult to electrically connect the stripe to an external wiring. In addition, since the connection with the drive circuit uses printed wiring, it is difficult to integrate the display device and the drive circuit, and there is a limit to the reduction in thickness.
[0007]
The present invention has been made in view of such a problem, and an object of the present invention is to provide a display device having a simple configuration and capable of improving uneven light emission, and a method for manufacturing the same.
[0008]
[Means for Solving the Problems]
A display device according to the present invention includes a display panel having a plurality of organic light emitting elements in which a transparent electrode, at least one organic layer including a light emitting layer, and a back electrode are sequentially laminated on a transparent substrate, and a plurality of organic light emitting elements of the display panel. A drive circuit board is provided facing the element side and is electrically connected directly to the transparent electrode and the back electrode for each of the plurality of organic light emitting elements.
[0009]
The method for manufacturing a display device according to the present invention includes a step of forming a display panel having a plurality of organic light emitting elements in which a transparent electrode, at least one organic layer including a light emitting layer, and a back electrode are sequentially laminated on a transparent substrate. Disposing the drive circuit board on the plurality of organic light emitting element sides of the display panel, and electrically connecting the drive circuit board directly to the transparent electrode and the back electrode for each of the plurality of organic light emitting elements. .
[0010]
In the display device and the method for manufacturing the same according to the present invention, the drive circuit board is disposed to face the plurality of organic light emitting elements of the display panel, and the electric power is directly applied to the transparent electrode and the back electrode for each of the plurality of organic light emitting elements. , The difference in resistance value due to the length of the distance from the drive circuit board is eliminated, the current value flowing through each organic light emitting element becomes uniform, and display is performed without causing uneven light emission. .
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0012]
[First Embodiment]
FIG. 1 shows a cross-sectional structure of the display device according to the first embodiment of the present invention. This display device is used as an ultra-thin organic EL display device or the like. For example, a display panel 10 and a drive circuit board 20 are arranged to face each other. The display panel 10 includes, for example, an organic light emitting element 10R that generates red light, an organic light emitting element 10G that generates green light, and a blue light on a transparent substrate 11 made of glass, quartz, resin, or the like. The generated organic light emitting elements 10B are sequentially provided in a matrix as a whole.
[0013]
The organic light-emitting elements 10R, 10G, and 10B have a structure in which, for example, a transparent electrode 12 as an anode, an organic layer 13, and a back electrode 14 as a cathode are stacked in this order from the transparent substrate 11 side. The organic light emitting elements 10R, 10G, and 10B are covered with an insulating layer 15 made of, for example, a silicon (Si) -based compound or an organic polymer. The insulating layer 15 is a protective film for preventing moisture and oxygen from entering the organic light emitting elements 10R, 10G, and 10B.
[0014]
The transparent electrode 12 is formed of a conductive material transparent in a visible light region, for example, indium tin oxide (ITO), in order to extract light from the side of the transparent substrate 11. The transparent electrode 12 has a stripe shape with a width of, for example, 0.3 mm and an interval of, for example, 0.3 mm, and a thickness in the stacking direction (hereinafter, simply referred to as a thickness) is, for example, about 200 nm. Each stripe of the transparent electrode 12 is insulated by an insulating layer (not shown).
[0015]
The configuration of the organic layer 13 is different for each of the organic light emitting elements 10R, 10G, and 10B. FIG. 2 illustrates an enlarged configuration of the organic layer 13 in the organic light emitting device 10G. In the organic light emitting device 10G, the organic layer 13 has a structure in which a hole injection layer 13A, a hole transport layer 13B, and a light emitting layer 13C made of organic materials are stacked in this order from the transparent electrode 12 side. The hole injection layer 13A and the hole transport layer 13B are for improving the efficiency of hole injection into the light emitting layer 13C. The light emitting layer 13C generates light by current injection.
[0016]
In the organic light emitting device 10G, the hole injection layer 13A has a thickness of, for example, about 50 nm, and is made of 4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) triphenylamine (MTDATA). The hole transport layer 13B has, for example, a thickness of about 20 nm and is made of bis [(N-naphthyl) -N-phenyl] benzidine (α-NPD). It is about 50 nm, and is composed of an 8-quinolinol aluminum complex (Alq).
[0017]
FIG. 3 shows an enlarged view of the configuration of the organic layer 13 in the organic light emitting devices 10R and 10B. In the organic light emitting devices 10R and 10B, the organic layer 13 has a hole injection layer 13A, a hole transport layer 13B, a light emitting layer 13C, and an electron transport layer 13D made of an organic material, which are stacked in this order from the transparent electrode 12 side. It has a structure. The electron transport layer 13D is for increasing the efficiency of injecting electrons into the light emitting layer 13C.
[0018]
In the organic light emitting device 10R, the hole injection layer 13A and the hole transport layer 13B are made of the same material as the organic light emitting device 10G, and the thickness of the hole injection layer 13A is, for example, about 50 nm. The thickness of the layer 13B is, for example, about 20 nm. The light emitting layer 13C has, for example, a thickness of about 30 nm, and is made of a mixture of Alq and 4-dicyanomethylene-6- (p-dimethylaminostyryl) -2-methyl-4H-pyran (DCM) mixed at 2% by volume. Have been. The electron transport layer 13D has, for example, a thickness of about 20 nm and is made of Alq.
[0019]
In the organic light emitting device 10B, the hole injection layer 13A and the hole transport layer 13B are made of the same material as the organic light emitting devices 10G and 10R, and the thickness of the hole injection layer 13A is, for example, about 50 nm. The thickness of the hole transport layer 13B is, for example, about 20 nm. The light emitting layer 13C has, for example, a thickness of about 30 nm and is made of bathocuproine (BCP). The electron transport layer 13D has, for example, a thickness of about 20 nm and is made of Alq.
[0020]
The back electrode 14 is formed of aluminum (Al), lithium (Li), silver (Ag), magnesium (Mg), indium (In), or the like. In this embodiment, for example, it is formed of an aluminum (Al) -lithium alloy having a purity of about 99% and containing lithium (Li) in a range of 0.01% to 0.05%. The back electrode 14 has a stripe shape orthogonal to the transparent electrode 12, and is formed to have an appropriate thickness of, for example, 30 nm or more and 500 nm or less.
[0021]
The insulating layer 15 has an appropriate thickness of, for example, 100 nm or more and several μm or less, and as shown in FIG. 1, the first opening 15A and the first opening 15A are provided for each of the organic light emitting elements 10R, 10G, and 10B. Two openings 15B are formed to penetrate insulating layer 15 in the thickness direction. The first opening 15A reaches the transparent electrode 12, and is filled with the first conductive connection 16A. Further, the second opening 15B reaches the back electrode 14, and is filled with the second conductive connecting portion 16B. The first opening 15A and the second opening 15B may have inclined side surfaces as shown in FIG. 1, but may have the side surfaces perpendicular to the transparent substrate 11. The planar shape of the first opening 15A and the second opening 15B can be any shape such as a circle and a polygon.
[0022]
The first conductive connection portion 16A and the second conductive connection portion 16B are preferably formed so as to reach the surface of the insulating layer 15 to facilitate electrical connection with the drive circuit board 20. It is more preferable to be formed so as to protrude from the surface of the insulating layer 15. The first conductive connecting portion 16A and the second conductive connecting portion 16B are preferably made of a metal such as nickel (Ni) or copper (Cu), but a polymer sphere is coated with gold (Au). It may be formed of a conductive polymer or the like in which conductive particles are dispersed.
[0023]
As shown in FIG. 1, the drive circuit board 20 is disposed to face the organic light emitting elements 10R, 10G, and 10B of the display panel 10. The drive circuit board 20 is formed of, for example, a printed wiring board, and a surface facing the organic light emitting elements 10R, 10G, 10B faces the transparent electrode 12 for each of the organic light emitting elements 10R, 10G, 10B. A first joint 21A is formed at a position, and a second joint 21B is formed at a position facing the back electrode 14.
[0024]
The first bonding portion 21A and the first conductive connection portion 16A face each other and are electrically connected by, for example, ultrasonic bonding. The second joint 21B and the second conductive connection 16B face each other and are electrically connected by, for example, ultrasonic bonding. Thereby, the first joint 21A is electrically connected to the transparent electrode 12 by the first conductive connection 16A, and the second joint 21B is electrically connected to the back electrode 14 by the second conductive connection 16B. Is electrically connected to
[0025]
The first joint 21A and the second joint 21B are formed to be larger than the first conductive connection 16A and the second conductive connection 16B by using, for example, stud bumps 22. Is preferred. Specifically, for example, the maximum diameter W of the first joint 21A and the second joint 21B _P Is the maximum diameter W of the first conductive connecting portion 16A and the second conductive connecting portion 16B. _B It is preferably formed larger than that. The first bonding portion 21A and the first conductive connecting portion 16A face each other to be electrically connected, and the second bonding portion 21B and the second conductive connecting portion 16B face each other and are electrically connected. This is because the bonding error can be absorbed at the time of manufacturing, and the manufacturing yield is improved. In addition, by using the stud bumps 22 in this manner, the first bonding portion 21A and the second bonding portion 21B have the entire thickness T including the stud bumps 22. _B Is the thickness T when printed on the drive circuit board 20. _A Is larger than.
[0026]
In order to form the first joint 21A and the second joint 21B larger than the first conductive connection 16A and the second conductive connection 16B, for example, besides the stud bump 22, As shown in FIG. 4, it is also possible to perform this by forming a plating layer 23 made of, for example, nickel or copper on the surfaces of the first joint 21A and the second joint 21B.
[0027]
Further, as shown in FIG. 5, the first joint 21A and the second joint 21B have a thickness T when printed on the drive circuit board 20. _A And maximum diameter W _A And the first conductive connecting portion 16A and the second conductive connecting portion 16B are made larger than the first bonding portion 21A and the second bonding portion 21B by using, for example, stud bumps 17. It may be. Further, in this case, the plating layer 23 may be formed on the surfaces of the first joint 21A and the second joint 21B.
[0028]
The adhesive layer 30 is formed in the gap between the insulating layer 15 and the drive circuit board 20, as shown in FIG. 1, and securely fixes the drive circuit board 20 to the display panel 10, and separates the drive circuit board 20. Is to be prevented. The adhesive layer 30 is made of, for example, an ultraviolet curable resin such as an epoxy resin. Alternatively, the adhesive layer 30 may be made of a thermosetting resin or a resin that cures over time. However, the adhesive layer 30 does not necessarily need to be provided.
[0029]
This display device can be manufactured, for example, as follows.
[0030]
6 to 9 show a method of manufacturing the display device in the order of steps. First, as shown in FIG. 6A, for example, on a transparent substrate 11 made of the above-described material, a stripe-shaped transparent electrode 12 made of the above-described material is formed by using an area mask (not shown) by, for example, a vacuum evaporation method. To form Next, an insulating layer (not shown) is formed between the stripes of the transparent electrode 12 by, for example, a CVD (Chemical Vapor Deposition) method, and the stripes of the transparent electrode 12 are electrically insulated.
[0031]
Subsequently, as shown in FIG. 6B, a hole injection layer 13A, a hole transport layer 13B, a light emitting layer 13C, and an electron transport layer 13D made of the above-described thickness and material are sequentially formed by, for example, a vacuum evaporation method. Film. At this time, an area mask used for the organic light emitting devices 10R, 10G, and 10B is changed, and a film is formed for each of the organic light emitting devices 10R, 10G, and 10B. After the organic layer 13 is formed, the back electrode 14 made of the above-described thickness and material is formed using, for example, an area mask (not shown) by a vapor deposition method. Thus, the display panel 10 is formed.
[0032]
Next, as shown in FIG. 7A, the organic light-emitting elements 10R, 10G, and 10B are covered with, for example, an insulating layer 15 made of the above-described material. , 10G, and 10B, a first opening 15A that penetrates the insulating layer 15 in the thickness direction and reaches the transparent electrode 12, and a first opening 15A that penetrates the insulating layer 15 in the thickness direction and reaches the back electrode 14. And two openings 15B. The first opening 15A and the second opening 15B may be formed by a method such as wet etching, ion milling, or sandblasting.
[0033]
Subsequently, as shown in FIG. 7B, the first opening 15A is filled with the first conductive connecting portion 16A, and the second opening 15B is filled with the second conductive connecting portion 16B. Is formed by filling.
[0034]
Further, as shown in FIG. 7C, a drive circuit board 20 which is a printed wiring board on which a drive circuit is formed is prepared, and the side of the drive circuit board 20 facing the organic light emitting elements 10R, 10G, 10B. In addition, a first bonding portion 21A is formed at a position facing the transparent electrode 12 and a second bonding portion 21B is formed at a position facing the back electrode 14 for each of the organic light emitting elements 10R, 10G, and 10B. I do. At this time, the first joint 21A and the second joint 21B are made larger than the first conductive connection 16A and the second conductive connection 16B by using the stud bumps 22. .
[0035]
Thereafter, as shown in FIG. 8, the drive circuit board 20 is disposed to face the organic light emitting elements 10R, 10G, and 10B of the display panel 10, and the drive circuit board 20 is temporarily provided by the adhesive layer 30 made of, for example, the above-described material. Fix it.
[0036]
Subsequently, as shown in FIG. 9, for example, using a high-frequency oscillator 40, the first bonding portion 21A and the first conductive connection portion 16A are opposed to each other and are electrically connected by ultrasonic bonding. At the same time, the second bonding portion 21B and the second conductive connection portion 16B are opposed to each other and are electrically connected by ultrasonic bonding. The high-frequency oscillator 40 has, for example, a piezoelectric element 42 connected to a power supply 41, and the vibration of the piezoelectric element 42 is applied to the first joint 21A or the second joint 21B via the arm 43 and the terminal 44. To be transmitted.
[0037]
As the conditions for ultrasonic bonding, for example, the connection load can be 5 g weight or more and 200 g weight per one place of the first bonding part 21A and the second bonding part 21B, and the time can be 3 ms or more and 10 s. The bonding method may be such that the first bonding portion 21A or the second bonding portion 21B is sequentially bonded one by one as shown in FIG. 9, or a high-frequency oscillator as shown in FIG. The first joint portion 21A and the second joint portion 21B may be joined together at a plurality of locations by using 50. The high-frequency oscillator 50 has a piezoelectric element 52 connected to a power supply 51, and is capable of adsorbing the drive circuit board 20 to an adsorbing portion 54 supported by a pair of fixed portions 53A, 53B.
[0038]
In this way, the transparent electrode 12 and the first joint 21A are electrically connected via the first conductive connection 16A, and the back electrode 14 is connected via the second conductive connection 16B. And the second joint 21B are electrically connected. After that, the adhesive layer 30 is cured so that the drive circuit board 20 is securely bonded to the display panel 10. Thereby, the separation of the drive circuit board 20 is prevented, and the reliability of the display device can be improved. The adhesive layer 30 may not be cured while being temporarily fixed. Further, the first bonding portion 21A and the second bonding portion 21B were electrically connected to the first conductive connecting portion 16A and the second conductive connecting portion 16B without performing the temporary fixing by the adhesive layer 30. Later, for example, the adhesive layer 30 made of the above-described material may be poured into the gap between the insulating layer 15 and the drive circuit board 20 to be cured.
[0039]
In the display device thus manufactured, when a predetermined voltage is applied between the transparent electrode 12 as an anode and the back electrode 14 as a cathode, a current is injected into the light emitting layer 13C, and holes and electrons are emitted. Is recombined, light emission occurs mainly at the interface on the light emitting layer 13C side. This light passes through the transparent electrode 12 and is extracted from the transparent substrate 11 side. In the present embodiment, the drive circuit board 20 is disposed facing the organic light emitting elements 10R, 10G, 10B of the display panel 10, and the transparent electrode 12 and the back electrode are provided for each of the organic light emitting elements 10R, 10G, 10B. 14, the difference in resistance value due to the length of the distance from the drive circuit board 20 is eliminated, the current values flowing through the organic light emitting elements 10R, 10G, and 10B become uniform, resulting in uneven light emission. Is improved. Therefore, the brightness of the screen becomes uniform, and even if the screen is enlarged and miniaturized, it is possible to display uniform brightness without uneven light emission.
[0040]
As described above, in the present embodiment, the drive circuit board 20 is disposed facing the organic light emitting elements 10R, 10G, 10B of the display panel 10, and the transparent electrode 12 is provided for each of the organic light emitting elements 10R, 10G, 10B. Also, since it is directly electrically connected to the back electrode 14, the difference in resistance value depending on the distance from the drive circuit board 20 is eliminated, and the current flowing through the organic light emitting elements 10R, 10G, 10B becomes uniform. In addition, light emission unevenness is improved. Therefore, the brightness of the screen becomes uniform, and even if the screen is enlarged and miniaturized, it is possible to display uniform brightness without uneven light emission. Further, the display panel 10 and the drive circuit board 20 are integrated, and a printed wiring board and the like are not required, so that the display device can be made thinner.
[0041]
Further, in the present embodiment, the first opening 15A and the back electrode reaching the transparent electrode 12 are provided on the insulating layer 15 covering the organic light emitting elements 10R, 10G, 10B for each of the organic light emitting elements 10R, 10G, 10B. 14, a second opening 15B is formed, and the first opening 15A and the second opening 15B are filled with a first conductive connecting portion 16A and a second conductive connecting portion 16B, respectively. Then, the first bonding portion 15A of the driving circuit board 20 and the first conductive connection portion 16A are opposed to each other to be electrically connected, and the second bonding portion 15B of the driving circuit board 20 is electrically connected to the second conductive portion 16A. The electrical connection portion 16 </ b> B is opposed to and electrically connected, so that the display device of the present embodiment can be easily reduced in size, and unevenness in light emission can be reduced to achieve high quality. be able to.
[0042]
Further, in the present embodiment, the first bonding portion 21A and the first conductive connecting portion 16A are opposed to each other to be electrically connected, and the second bonding portion 21B and the second conductive connecting portion 16B And the step of electrically connecting them to each other by using ultrasonic bonding, electrical connection can be performed at a relatively low temperature of room temperature to 120 ° C. or lower, and the organic light emitting elements 10R, 10R, There is no fear of deterioration of 10G and 10B, and a high-quality display device can be realized.
[0043]
In addition, in the present embodiment, since the adhesive layer 30 is formed in the gap between the insulating layer 15 and the drive circuit board 20, the drive circuit board 20 is securely bonded to the display panel 10, and the drive circuit board 20 Can be prevented, and the reliability of the display device can be improved.
[0044]
Further, in the present embodiment, the first bonding portion 21A and the second bonding portion 21B are formed larger than the first conductive connecting portion 16A and the second conductive connecting portion 16B. The first bonding portion 21A and the first conductive connecting portion 16A face each other to be electrically connected, and the second bonding portion 21B and the second conductive connecting portion 16B face each other to be electrically connected. At this time, the bonding error can be absorbed, and the manufacturing yield can be improved.
[0045]
[Second embodiment]
Next, a display device according to a second embodiment of the present invention will be described. In this display device, the first joint 21A and the first conductive connection 16A are opposed to each other to be electrically connected, and the second joint 21B and the second conductive connection 16B are opposed to each other. The display device is the same as the display device described in the first embodiment with reference to FIGS. 1 to 3 except that the step of making electrical connection is performed using a conductive resin. Therefore, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted.
[0046]
In this display device, as shown in FIG. 11, the first bonding portion 21A and the first conductive connection portion 16A face each other and include, for example, conductive particles obtained by applying a gold coating to a polymer sphere. They are electrically connected via a conductive resin 60 formed by an anisotropic conductive paste (ACP; Anisotropic Conductive Paste). Similarly, the second bonding portion 21B and the second conductive connecting portion 16B face each other, and are electrically connected through, for example, the conductive resin 60. Thereby, the first joint 21A is electrically connected to the transparent electrode 12 by the first conductive connection 16A, and the second joint 21B is electrically connected to the back electrode 14 by the second conductive connection 16B. Is electrically connected to
[0047]
The display device having the conductive resin 60 as shown in FIG. 11 can be manufactured, for example, as follows. That is, first, as described with reference to FIGS. 6 and 7 in the first embodiment, the display panel 10 and the drive circuit board 20 are respectively formed.
[0048]
Subsequently, as shown in FIG. 12A, a conductive resin 60 made of, for example, the above-described material is applied to the first conductive connection portion 16A and the second conductive connection portion 16B.
[0049]
After the conductive resin 60 is applied and formed, as shown in FIG. 12 (B), the drive circuit board 20 is arranged to face the organic light emitting elements 10R, 10G, 10B of the display panel 10, and a predetermined temperature and pressure are applied. The conductive resin 60 is hardened by heating and pressing. The conductive resin 60 may be a two-component resin or may be irradiated with ultraviolet rays in order to accelerate curing.
[0050]
After the conductive resin 60 is cured, the adhesive layer 30 is formed in the gap between the insulating layer 15 and the drive circuit board 20. However, the adhesive layer 30 does not necessarily need to be provided.
[0051]
As described above, in the present embodiment, the first bonding portion 21A and the first conductive connection portion 16A are opposed to each other to be electrically connected, and the second bonding portion 21B and the second conductive connection portion 16B Are electrically connected at a relatively low temperature of room temperature to 120 ° C. or lower, and the organic light emitting element 10R is heated. , 10G, and 10B without deterioration, and a high-quality display device can be realized.
[0052]
[Third Embodiment]
Next, a display device according to a third embodiment of the present invention will be described. In this display device, the first joint 21A and the first conductive connection 16A are opposed to each other to be electrically connected, and the second joint 21B and the second conductive connection 16B are opposed to each other. The second embodiment is the same as the second embodiment except that the step of making electrical connection is performed using a film-shaped conductive resin. Therefore, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted.
[0053]
In this display device, as shown in FIG. 13, the first bonding portion 21A and the first conductive connection portion 16A face each other, and for example, an anisotropic conductive film (ACF; Anisotropic) containing conductive particles. It is electrically connected via a film-like conductive resin 61 formed by a conductive film or the like. Similarly, the second bonding portion 21B and the second conductive connection portion 16B face each other, and are electrically connected to each other via, for example, a film-shaped conductive resin 61. Thereby, the first joint 21A is electrically connected to the transparent electrode 12 by the first conductive connection 16A, and the second joint 21B is electrically connected to the back electrode 14 by the second conductive connection 16B. Is electrically connected to
[0054]
The display device having the film-shaped conductive resin 61 as shown in FIG. 13 can be manufactured, for example, as follows. That is, first, as described with reference to FIGS. 6 and 7 in the first embodiment, the display panel 10 and the drive circuit board 20 are respectively formed.
[0055]
Subsequently, as shown in FIG. 14A, a film-shaped conductive resin 61 made of, for example, the above-described material is attached to the first conductive connection portion 16A and the second conductive connection portion 16B. . At this time, it is preferable to use a flat jig (not shown) so that the display panel 10 and the drive circuit board 20 are parallel.
[0056]
After the film-shaped conductive resin 61 is adhered and formed, as shown in FIG. 14B, the drive circuit board 20 is arranged to face the organic light emitting elements 10R, 10G, and 10B of the display panel 10, and The film-shaped conductive resin 61 is cured by heating and pressing at a temperature and pressure. The film-shaped conductive resin 61 may be irradiated with ultraviolet rays in order to accelerate curing.
[0057]
After the film-shaped conductive resin 61 is cured, the adhesive layer 30 is formed in the gap between the insulating layer 15 and the drive circuit board 20. However, the adhesive layer 30 does not necessarily need to be provided.
[0058]
As described above, in the present embodiment, the first bonding portion 21A and the first conductive connection portion 16A are opposed to each other to be electrically connected, and the second bonding portion 21B and the second conductive connection portion 16B And the step of electrically connecting them with each other is performed using the film-shaped conductive resin 61, so that the electrical connection can be performed at a relatively low temperature of room temperature to 120 ° C. or lower, and the organic matter by heat can be obtained. There is no fear of deterioration of the light emitting elements 10R, 10G, 10B, and a high quality display device can be realized.
[0059]
[Fourth Embodiment]
Next, a display device according to a fourth embodiment of the present invention will be described. In this display device, the first joint 21A and the first conductive connection 16A are opposed to each other to be electrically connected, and the second joint 21B and the second conductive connection 16B are opposed to each other. The display device is the same as the display device described with reference to FIGS. 1 to 3 in the first embodiment, except that the step of making electrical connection is performed by pressure bonding after plasma cleaning. Therefore, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted.
[0060]
This display device can be manufactured, for example, as follows. That is, first, as described with reference to FIGS. 6 and 7 in the first embodiment, the display panel 10 and the drive circuit board 20 are respectively formed.
[0061]
Subsequently, as shown in FIGS. 15A and 15B, the display panel 10 and the driving circuit board 20 are each subjected to plasma cleaning by irradiating the plasma 70 in a vacuum to form the first conductive film. The impurities on the metal surfaces of the conductive connection portion 16A and the second conductive connection portion 16B, and the first bonding portion 21A and the second bonding portion 21B are removed. Thereafter, as shown in FIG. 16, the drive circuit board 20 is disposed to face the organic light-emitting elements 10R, 10G, and 10B of the display panel 10, and is pressed at a predetermined pressure, so that the first conductive connection portion is formed. 16A and the second conductive connecting portion 16B and the conductive resin 60 of the first bonding portion 21A and the second bonding portion 21B are respectively crimped and electrically and mechanically connected.
[0062]
After the pressure bonding, an adhesive layer 30 is formed in a gap between the insulating layer 15 and the drive circuit board 20. However, the adhesive layer 30 does not necessarily need to be provided.
[0063]
As described above, in the present embodiment, the first bonding portion 21A and the first conductive connection portion 16A are opposed to each other to be electrically connected, and the second bonding portion 21B and the second conductive connection portion 16B Is electrically connected at a relatively low temperature of room temperature to 120 ° C. or less, and the organic light emitting element 10R is heated. , 10G, and 10B without deterioration, and a high-quality display device can be realized.
[0064]
[Fifth Embodiment]
Next, a display device according to a fifth embodiment of the present invention will be described. In this display device, the first joint 21A and the first conductive connection 16A are opposed to each other to be electrically connected, and the second joint 21B and the second conductive connection 16B are opposed to each other. The display device is the same as the display device described in the first embodiment with reference to FIGS. 1 to 3 except that the step of making electrical connection is performed using a conductive paste. Therefore, the same components are denoted by the same reference numerals, and detailed description thereof will be omitted.
[0065]
In this display device, as shown in FIG. 17, the first bonding portion 21A and the first conductive connection portion 16A face each other and include, for example, conductive particles obtained by applying a gold coating to a polymer sphere. They are electrically connected via the conductive paste 62. Similarly, the second bonding portion 21B and the second conductive connection portion 16B face each other and are electrically connected via, for example, a conductive paste 62. Thereby, the first joint 21A is electrically connected to the transparent electrode 12 by the first conductive connection 16A, and the second joint 21B is electrically connected to the back electrode 14 by the second conductive connection 16B. Is electrically connected to
[0066]
The display device having the conductive paste 62 as shown in FIG. 17 can be manufactured, for example, as follows. That is, first, as described with reference to FIGS. 6 and 7 in the first embodiment, the display panel 10 and the drive circuit board 20 are respectively formed.
[0067]
Subsequently, as shown in FIG. 18A, the surface of the drive circuit board 20 is immersed in a bath 62A in which the conductive paste 62 is stretched in a container 63, and the first bonding portion 21A and the second bonding portion The conductive paste 62 is attached only to the tip of 21B.
[0068]
After the conductive paste 62 is applied, as shown in FIG. 18 (B), the drive circuit board 20 is disposed to face the organic light emitting elements 10R, 10G, 10B of the display panel 10 and heated at a predetermined temperature, for example. By doing so, the conductive paste 62 is cured. The hardening of the conductive paste 62 may be performed by ultraviolet irradiation.
[0069]
After the conductive paste 62 is cured, the adhesive layer 30 is formed in the gap between the insulating layer 15 and the drive circuit board 20. However, the adhesive layer 30 does not necessarily need to be provided.
[0070]
As described above, in the present embodiment, the first bonding portion 21A and the first conductive connection portion 16A are opposed to each other to be electrically connected, and the second bonding portion 21B and the second conductive connection portion 16B Are electrically connected at a relatively low temperature of room temperature to 120 ° C. or lower, and the organic light emitting element 10R is heated. , 10G, and 10B without deterioration, and a high-quality display device can be realized.
[0071]
As described above, the present invention has been described with reference to the embodiment. However, the present invention is not limited to the above embodiment, and various modifications are possible. For example, in the above-described embodiment, the configurations of the organic light emitting elements 10R, 10G, and 10B have been specifically described. However, it is not necessary to provide all the layers, and other layers may be further provided.
[0072]
Furthermore, in the above embodiment, one drive circuit board 20 is provided for the display panel 10, but the present invention divides the display panel 10 into several blocks, and The present invention is also applicable to a configuration in which divided driving is performed. In this case, a configuration in which the transparent electrodes 12 are formed as one division unit for a predetermined number of the back electrodes 14, for example, every 64, and the drive circuit board 20 corresponding to each of the predetermined number of the back electrodes 14 is provided. It becomes.
[0073]
In addition, in the above-described embodiment, red, green, and blue light are generated by changing the material of the organic layer 13. However, the present invention combines color conversion layers (CCMs). Alternatively, the present invention can be applied to a display device that generates these lights by combining color filters. Further, it is needless to say that the present invention is applicable not only to a color display device but also to a case of a single color display.
[0074]
【The invention's effect】
As described above, according to the display device according to any one of claims 1 to 5, or the method of manufacturing the display device according to any one of claims 6 to 12, the driving circuit Since the substrate is disposed to face the plurality of organic light emitting elements of the display panel and is directly electrically connected to the transparent electrode and the back electrode for each of the plurality of organic light emitting elements, the distance from the drive circuit board is reduced. The difference in resistance value due to the length is eliminated, the current value flowing through each organic light emitting element becomes uniform, and uneven light emission is improved. Therefore, the brightness of the screen becomes uniform, and even if the screen is enlarged and miniaturized, it is possible to display uniform brightness without uneven light emission. Further, since the display panel and the drive circuit board are integrated, and a printed wiring board or the like is not required, the display device can be made thinner.
[0075]
In particular, according to the display device of the second aspect or the method of manufacturing the display device of the seventh aspect, the insulating layer covering the plurality of organic light-emitting elements is provided on each of the plurality of organic light-emitting elements to reach the transparent electrode. The first opening and the second opening reaching the back electrode are formed, and the first opening and the second opening are filled with the first conductive connection and the second conductive connection, respectively. The first bonding portion of the drive circuit board and the first conductive connection portion are opposed to each other to be electrically connected to each other, and the second connection portion of the drive circuit board and the second conductive connection portion are formed. Are electrically opposed to each other, so that the size of the display device of the present invention can be easily reduced, and unevenness in light emission can be reduced to achieve high quality.
[0076]
In addition, in particular, according to the method of manufacturing a display device according to any one of claims 8 to 12, the first bonding portion and the first conductive connection portion are electrically connected to each other. In addition, the step of electrically connecting the second joint portion and the second conductive connection portion while facing each other is performed by ultrasonic bonding, conductive resin, film-like conductive resin, or plasma cleaning. Since the bonding is performed later by using pressure bonding or using a conductive paste, electrical connection can be performed at a relatively low temperature of room temperature to 120 ° C. or less, and there is no risk of deterioration of the organic light emitting element due to heat, and high quality is achieved. Can be realized.
[0077]
In addition, in particular, according to the display device of the fifth aspect, since the adhesive layer is formed in the gap between the insulating layer and the drive circuit board, the drive circuit board is securely bonded to the display panel, and the drive circuit The peeling of the substrate can be prevented, and the reliability of the display device can be improved.
[0078]
Further, in particular, according to the display device of the third or fourth aspect, the first joint and the second joint are larger than the first conductive connection and the second conductive connection. Since it is formed, the first bonding portion and the first conductive connecting portion are opposed to each other to be electrically connected, and the second bonding portion and the second conductive connecting portion are opposed to each other to electrically connect. When connecting to, the bonding error can be absorbed, and the manufacturing yield can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a configuration of a display device according to a first embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view illustrating a configuration of an organic light emitting element in the display device shown in FIG.
FIG. 3 is an enlarged cross-sectional view illustrating a configuration of an organic light emitting element in the display device illustrated in FIG.
FIG. 4 is a cross-sectional view illustrating another configuration of a first bonding portion and a second bonding portion in the display device illustrated in FIG.
5 is a cross-sectional view illustrating another configuration of a first conductive connection portion and a second conductive connection portion in the display device illustrated in FIG.
FIG. 6 is a plan view illustrating a method of manufacturing the display device illustrated in FIG. 1 in a process order.
FIG. 7 is a cross-sectional view illustrating a process following the process in FIG.
FIG. 8 is a cross-sectional view illustrating a process following FIG.
FIG. 9 is a cross-sectional view illustrating a process following the process in FIG.
FIG. 10 is a cross-sectional view illustrating another example for performing the step illustrated in FIG. 9B.
FIG. 11 is a sectional view illustrating a configuration of a display device according to a second embodiment of the present invention.
12 is a cross-sectional view illustrating a method of manufacturing the display device illustrated in FIG. 11 in the order of steps.
FIG. 13 is a cross-sectional view illustrating a configuration of a display device according to a third embodiment of the present invention.
FIG. 14 is a cross-sectional view illustrating a method of manufacturing the display device illustrated in FIG. 13 in a process order.
FIG. 15 is a cross-sectional view illustrating a method of manufacturing a display device according to a fourth embodiment of the present invention in the order of steps.
FIG. 16 is a sectional view illustrating a step following FIG. 15;
FIG. 17 is a cross-sectional view illustrating a configuration of a display device according to a fifth embodiment of the present invention.
18 is a cross-sectional view illustrating a method of manufacturing the display device illustrated in FIG. 17 in the order of steps.
[Explanation of symbols]
Reference Signs List 10: display panel, 10R, 10G, 10B: organic light-emitting element, 11: transparent substrate, 12: transparent electrode (anode), 13: organic layer, 13A: hole injection layer, 13B: hole transport layer, 13C: light emission Layer, 13D: electron transport layer, 14: back electrode (cathode), 15: insulating layer, 15A: first opening, 15B: second opening, 16A: first conductive connecting portion, 16B: first 2 conductive connecting portion, 17 stud bump, 20 drive circuit board, 21A first joining portion, 21B second joining portion, 22 stud bump, 23 plating layer, 30 adhesive layer, 60 ... conductive resin, 61 ... film-shaped conductive resin, 62 ... conductive paste

Claims (12)

A display panel having a plurality of organic light-emitting elements in which a transparent electrode, one or more organic layers including a light-emitting layer, and a back electrode are sequentially laminated on a transparent substrate;
A drive circuit board that is disposed to face the plurality of organic light emitting elements of the display panel and that is directly electrically connected to the transparent electrode and the back electrode for each of the plurality of organic light emitting elements. A display device characterized by the above-mentioned. The drive circuit board,
A first bonding portion provided on a surface facing the plurality of organic light emitting elements at a position facing the transparent electrode for each of the plurality of organic light emitting elements;
A second bonding portion provided on a surface facing the plurality of organic light emitting elements at a position facing the back electrode for each of the plurality of organic light emitting elements,
The display panel includes:
An insulating layer covering the plurality of organic light emitting elements,
For each of the plurality of organic light emitting elements, a first opening reaching the transparent electrode through the insulating layer in the thickness direction thereof,
For each of the plurality of organic light-emitting elements, a second opening reaching the back electrode through the insulating layer in the thickness direction thereof,
A first conductive connecting portion that is filled in the first opening portion and directly electrically connects the transparent electrode and the first bonding portion of the drive circuit board;
The semiconductor device according to claim 1, further comprising a second conductive connection portion that is filled in the second opening and that directly electrically connects the back electrode and the second bonding portion of the drive circuit board. Item 2. The display device according to Item 1. The display according to claim 1, wherein the first joint and the second joint are formed larger than the first conductive connection and the second conductive connection. apparatus. The first junction and the second junction are formed larger than the first conductive connection and the second conductive connection by a stud bump or a plating layer. 4. The display device according to claim 3, wherein: The display device according to claim 1, wherein an adhesive layer is formed in a gap between the insulating layer and the drive circuit board. Forming a display panel having a plurality of organic light-emitting elements in which a transparent electrode, one or more organic layers including a light-emitting layer, and a back electrode are sequentially laminated on a transparent substrate;
A drive circuit board is disposed to face the plurality of organic light emitting elements of the display panel, and the drive circuit board is directly electrically connected to the transparent electrode and the back electrode for each of the plurality of organic light emitting elements. And a method of manufacturing a display device. On the surface of the drive circuit board facing the plurality of organic light-emitting elements, a first joint is formed at a position facing the transparent electrode for each of the plurality of organic light-emitting elements and at the same time, facing the back electrode. Forming a second joint at a position where
A step of covering the plurality of organic light-emitting elements with an insulating layer;
In the insulating layer, for each of the plurality of organic light emitting elements, a first opening reaching the transparent electrode through the insulating layer in a thickness direction thereof is formed, and the insulating layer is penetrated in the thickness direction thereof. Forming a second opening reaching the back electrode;
Filling the first opening with a first conductive connection and filling the second opening with a second conductive connection;
The first junction and the first conductive connection are opposed to each other to be electrically connected, and the second junction and the second conductive connection are opposed to be electrically connected to each other. 7. The method for manufacturing a display device according to claim 6, further comprising the steps of: The first junction and the first conductive connection are opposed to each other to be electrically connected, and the second junction and the second conductive connection are opposed to be electrically connected to each other. 8. The method for manufacturing a display device according to claim 7, wherein the step of performing is performed using ultrasonic waves. The first junction and the first conductive connection are opposed to each other to be electrically connected, and the second junction and the second conductive connection are opposed to be electrically connected to each other. 8. The method according to claim 7, wherein the step of performing is performed using a conductive resin. The method according to claim 9, wherein a film-shaped conductive resin is used as the conductive resin. The first junction and the first conductive connection are opposed to each other to be electrically connected, and the second junction and the second conductive connection are opposed to be electrically connected to each other. 8. The method for manufacturing a display device according to claim 7, wherein the step of performing is performed by pressure bonding after plasma cleaning. The first junction and the first conductive connection are opposed to each other to be electrically connected, and the second junction and the second conductive connection are opposed to be electrically connected to each other. 8. The method according to claim 7, wherein the step of performing is performed using a conductive paste.

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