JP2001250686A - Light emission element and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a light emission element to which a formation method of an electrode is not restricted by a material of a light emission layer, and its manufacturing method. SOLUTION: In the light emission element equipped with an anode 2 which consists of two or more electrodes, a negative pole 5 comprising two or more electrodes, a light emission layer 4 put between the anode 2 and the negative pole 5, the element is manufactured through process steps in which the anode 2 and the light emission layer 4 are formed on a substrate 1A, the negative pole 5 is formed on a substrate 1B, and a thermo-compression bonding process step in which, the 1A equipped with the anode 2 and the light emission layer 4 and the substrate 1B equipped with the pole 5 are adhered by thermo- compression bonding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a light emitting device having a light emitting layer sandwiched between electrodes and a method for manufacturing the same.

[0002]

2. Description of the Related Art There is known an electroluminescence panel which displays an arbitrary image by light emission when a predetermined voltage is applied to a light emitting layer. Such an electroluminescent panel includes a plurality of anodes and cathodes arranged in a stripe shape in a direction orthogonal to each other, and the above-described light emitting layer is sandwiched between the anodes and the cathodes. By controlling the current at the intersections arranged in a matrix constituted by the intersection of the anode and the cathode, the presence or absence of light emission at each intersection is controlled. Thereby, an arbitrary image can be displayed using each intersection as a pixel.

[0003]

However, when the light emitting material is an organic material or when the light emitting layer contains an organic material, it is difficult to form an anode or a cathode at a fine pitch. That is, for example, when trying to form each layer in the order of anode, light emitting layer, cathode,
If the cathode is formed using the photolithography technique after the formation of the light emitting layer, the light emitting layer is damaged by a resist developing solution or an electrode etching solution during the patterning of the cathode, so that the cathode cannot be patterned. There is a problem. Although it is conceivable to form the cathode by a method other than photolithography, it is difficult to cope with a fine pitch. Even if the order of forming each layer is changed and the cathode, the light emitting layer, and the anode are formed in this order, the anode cannot be formed using the photolithography technique for the same reason as described above, and fine pitch patterning is performed. Can not respond to.

An object of the present invention is to provide a light emitting device in which a method of forming an electrode is not limited by a material of a light emitting layer, and a method of manufacturing the same.

[0005]

The light emitting device of the present invention comprises a first electrode group (2) comprising a plurality of electrodes, a second electrode group (5) comprising a plurality of electrodes, and a first electrode group. Light emitting layer (4) sandwiched between group (2) and second electrode group (5)
Forming a first electrode group (2) and a light emitting layer (4) on a first substrate (1A), and forming a second electrode group (5) on a second substrate ( 1B), a first substrate (1A) on which a first electrode group (2) and a light emitting layer (4) are formed, and a second substrate on which a second electrode group (5) is formed. And a thermocompression bonding step of thermocompression bonding the substrate (1B) (FIGS. 1 to 4).

According to the present invention, the first electrode group (2) is formed on the first substrate (1A), and the second electrode group (5) is formed on the second substrate (1B). The first substrate (1
Since A) and the second substrate (1B) are thermocompression bonded, photolithography technology can be used when forming the first electrode group (2) and the second electrode group (5). Therefore, for example, the first electrode group (2) and the second electrode group (5) can be formed at a fine pitch.

In the thermocompression bonding step, a thermocompression bonding layer formed on the first substrate (1A) or the second substrate (1) is formed.
The pressure-bonded layer formed in B) may have heat-fusibility.

[0008] In this case, the first substrate (1A) can be used without interposing a hot-melt sheet or the like between the first substrate (1A) and the second substrate (1B) in the thermocompression bonding step. And the second substrate (1B) can be thermocompression-bonded to each other.

The pressure-bonding layer may have the lowest glass transition temperature among the layers constituting the light emitting device.

In this case, the first substrate (1A) and the second substrate (1B) can be thermocompression-bonded to each other by melting the pressure-bonding layer without damaging other layers.

The method for manufacturing a light-emitting device according to the present invention includes a first electrode group (2) including a plurality of electrodes, a second electrode group (5) including a plurality of electrodes, and a first electrode group (2). ) And the second
And a light emitting layer (4) sandwiched between the electrode groups (5) of (1), wherein the first electrode group (2) and the light emitting layer (4) are formed on a first substrate (1A). Forming a second electrode group (5) on a second substrate (1B)
And a first substrate (1A) on which the first electrode group (2) and the light emitting layer (4) are formed, and a second substrate (1A) on which the second electrode group (5) is formed. 1B) and a thermocompression bonding step of thermocompression bonding (FIG. 1 to FIG. 4).

According to the present invention, after the first electrode group (2) is formed on the first substrate (1A) and the second electrode group (5) is formed on the second substrate (1B), The first substrate (1
Since A) and the second substrate (1B) are thermocompression bonded, photolithography technology can be used when forming the first electrode group (2) and the second electrode group (5). Therefore, for example, the first electrode group (2) and the second electrode group (5) can be formed at a fine pitch.

In the thermocompression bonding step, heating may be performed to a temperature close to the glass transition temperature of a layer having a low glass transition temperature among the compression layer of the first substrate (1A) or the compression layer of the second substrate (1B).

In this case, other layers other than the layer having a low glass transition temperature among the compression layers of the first substrate (1A) or the compression layers of the second substrate (1B) are not excessively heated,
Since the first substrate (1A) and the second substrate (1B) can be thermocompression bonded, the influence on these other layers can be minimized.

In the thermocompression bonding step, the first substrate (1A) and the second substrate (1B) are thermocompression bonded while the light emitting layer (4) and the second electrode group (5) are overlapped. (FIG. 4).

A step of forming a hole transport layer (3) on the second electrode group (2) formed on the second substrate (1A) is provided. In the thermocompression bonding step, a light emitting layer (4) is formed. The first substrate (1B) and the second substrate (1A) may be thermocompression bonded together with the hole transport layer (3) (FIG. 5).

A step of forming a hole transport layer (3) on the light emitting layer (4) formed on the first substrate (1B) is provided. In the thermocompression bonding step, a first electrode group (2) is formed. The first substrate (1B) and the second substrate (1B) are overlapped with the hole transport layer (3).
(1A) may be thermocompression bonded (FIG. 6).

The first electrode group (2, 5) may be formed using a photolithography technique. In this case, the first electrode group (2, 5) can be formed without damaging the light emitting layer (4), and for example, it can be formed at a fine pitch.

The second electrode group (2, 5) may be formed by using photolithography. In this case, the second electrode group (2, 5) can be formed without damaging the light emitting layer (4), and for example, it can be formed at a fine pitch.

Note that, in order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are added in parentheses, but the present invention is not limited to the illustrated embodiment.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment A first embodiment in which a light emitting device of the present invention is applied to an electroluminescent device will be described below with reference to FIGS.

FIG. 1 is a cross-sectional view of an electroluminescent panel in which the light emitting elements of the first embodiment are arranged in a matrix, FIG. 2 is a diagram showing the direction of electrodes, and FIG. 3 is a layer configuration of the electroluminescent panel. FIG. 4, FIG.
FIG. 3 is a cross-sectional view illustrating a method for manufacturing an electroluminescence panel.

As shown in FIGS. 1 to 3, the electroluminescence panel 100 includes a substrate 1A and a substrate 1B. Between the substrate 1A and the substrate 1B, an anode 2, a hole transport layer 3, a light emitting layer 4, and a cathode 5 made of aluminum formed in a stripe shape are respectively provided. .

As the substrate 1A and the substrate 1B, a substrate made of an inorganic material such as glass may be used, or a substrate made of a flexible material such as a polymer film may be used.

As a material of the hole transport layer 3, for example,
Aromatic tertiary amines, derivatives of triphenylamine, fluorene derivatives, stilbene compounds, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, porphyrin derivatives, phenylenediamine derivatives, arylamines Derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styryl anthracene derivatives, hydrazone derivatives, silazane derivatives, polysilane-based aniline-based polymers, styrylamine compounds, organic compounds such as aromatic dimethylidin-based compounds, polymers such as polyolefin-based derivatives, or A dispersion system in which a low-molecular-weight hole transport agent is mixed in a polymer is exemplified.

Examples of the material of the light-emitting layer 4 include 8-hydroxyquinoline-based metal complexes, coumarin derivatives, benzoxazole-based, benzothiazole-based, benzimidazole-based, styrylbenzene-based compounds, distyrpyrazine derivatives, naphthalimide derivatives, Organic compounds such as perylene derivatives, oxadiazole derivatives, aldazine derivatives, metal-chelating oxinoid compounds, aromatic dimethylidin derivatives, polymers such as polyolefin derivatives, polyparaphenylenevinylene derivatives, and polythiophene derivatives, or in polymers A dispersion system mixed with a low-molecular luminescent agent is exemplified.

An electron transport layer (not shown) may be inserted between the cathode and the light emitting layer.

As shown in FIG. 2, the anode 2 and the cathode 5 are formed in directions orthogonal to each other, and a pixel is formed at the intersection of the anode 2 and the cathode 5. By applying a voltage between the selected anode 2 and cathode 5, a predetermined portion of the light emitting layer 4 emits light as a selected pixel, and a predetermined image can be displayed. Light emission of the light emitting layer 4 is visually recognized from the substrate 1A side. In addition, the electroluminescence panel 1
Known driving methods such as a simple matrix method and an active matrix method can be applied as the 00 driving method, but the description thereof is omitted.

Hereinafter, a method for manufacturing the electroluminescent panel 100 will be described with reference to FIG.

As shown in FIG. 4A, an anode 2, a hole transport layer 3, and a light emitting layer 4 are formed inside a substrate 1A.
First, the IT is formed on the substrate 1A by using a sputtering method or the like.
A transparent conductive film such as O is formed, and a photoresist is formed on the transparent conductive film. Thereafter, the photoresist is patterned by exposure and development steps, the transparent conductive film is etched using the patterned photoresist as a mask to form the anode 2, and then the photoresist is removed. Next, the hole transport layer 3 is formed on the anode 2 by an evaporation method or the like, and the light emitting layer 4 is formed by an evaporation method or the like.

On the other hand, as shown in FIG. 4B, a cathode 5 is formed inside the substrate 1B. First, an aluminum film is formed on the substrate 1B by an evaporation method or the like, and a photoresist is formed on the aluminum film. Thereafter, the photoresist is patterned by exposure and development steps, the aluminum film is etched using the patterned photoresist as a mask to form the cathode 5, and then the photoresist is removed.

Next, as shown in FIG.
And the cathode 5 are superimposed, heat and pressure are applied, and thermocompression bonding is performed. By thus integrating the substrate 1A and the substrate 1B, the electroluminescent panel 100 is formed. In this case, the glass transition temperature of the light-emitting layer 4 is set lower than the glass transition temperature of each of the other layers, and the other layers are affected by heating to a vicinity of the glass transition temperature of the light-emitting layer 4 in the thermocompression bonding step. The light emitting layer 4 can be melted without heat and the light emitting layer 4 and the cathode 5 can be thermocompression bonded.

In the first embodiment, the anode 2 is formed inside the substrate 1A and the cathode 5 is formed inside the substrate 1B, and then the substrate 1A and the substrate 1B are thermocompression-bonded to manufacture an electroluminescent panel. are doing. Therefore, even if a photolithography process is used when forming the anode 2 and the cathode 5, the underlying layer of the anode 2 or the cathode 5 may be damaged by a developing solution of the resist, an etching solution of the electrode, a stripping solution of the resist, or the like. Absent. Accordingly, it is possible to cope with a case where the anode 2 or the cathode 5 must be formed at a fine pitch.

Regarding the correspondence between the first embodiment and the claims, the substrate 1A corresponds to the first substrate, the substrate 1B corresponds to the second substrate, the anode 2 corresponds to the first electrode group, and the cathode 5 corresponds to the second substrate. , Respectively. Further, the light emitting layer 4 and the cathode 5
Correspond to the pressure bonding layer of the first substrate and the pressure bonding layer of the second substrate, respectively.

-Second Embodiment- A second embodiment in which the light emitting device of the present invention is applied to an electroluminescence device will be described below with reference to FIG. The second embodiment differs from the first embodiment in the method for manufacturing an electroluminescent panel.

FIGS. 5A to 5C are cross-sectional views illustrating a method of manufacturing the electroluminescent panel 100A. 5A to 5C, the same elements as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 5A, an anode 2 and a hole transport layer 3 are formed inside a substrate 1A. First, a transparent conductive film such as ITO is formed on the substrate 1A by a sputtering method or the like, and a photoresist is formed on the transparent conductive film. Thereafter, the photoresist is patterned by exposure and development steps, the transparent conductive film is etched using the patterned photoresist as a mask to form the anode 2, and then the photoresist is removed. Next, the hole transport layer 3 is formed on the anode 2 using an evaporation method or the like.

On the other hand, as shown in FIG. 5B, a cathode 5 and a light emitting layer 4 are formed inside the substrate 1B. First, an aluminum film is formed on the substrate 1B using an evaporation method or the like,
A photoresist is formed on the aluminum film. Thereafter, the photoresist is patterned by exposure and development steps, the aluminum film is etched using the patterned photoresist as a mask to form the cathode 5, and then the photoresist is removed. Next, the light emitting layer 4 is formed on the cathode 5 by using an evaporation method or the like.

Next, as shown in FIG. 5 (c), the hole transport layer 3 and the light emitting layer 4 are overlaid, heat and pressure are applied, and thermocompression bonding is performed. By thus integrating the substrate 1A and the substrate 1B, the electroluminescence panel 1
00A is formed. In this case, the glass transition temperature of the hole transport layer 3 or the light emitting layer 4 is set lower than the glass transition temperature of the other layers, and the lower glass transition temperature of the hole transport layer 3 or the light emitting layer 4 in the thermocompression bonding step. By heating to near the temperature, the layer having the lowest glass transition temperature can be melted without affecting other layers, and the hole transport layer 3 and the light emitting layer 4 can be thermocompression bonded.

In the second embodiment, similarly to the first embodiment, after the anode 2 is formed inside the substrate 1A and the cathode 5 is formed inside the substrate 1B, the substrates 1A and 1B are thermocompression-bonded. By doing so, an electroluminescent panel is manufactured. For this reason, a photolithography step can be used when forming the anode 2 and the cathode 5, and therefore, it is possible to cope with the case where the anode 2 or the cathode 5 must be formed at a fine pitch.

Regarding the correspondence between the second embodiment and the claims, the substrate 1B is the first substrate, the substrate 1A is the second substrate, the cathode 5 is the first electrode group, and the anode 2 is the second electrode. , Respectively. Further, the light emitting layer 4 and the hole transport layer 3 correspond to the pressure bonding layer of the first substrate and the pressure bonding layer of the second substrate, respectively.

Third Embodiment A third embodiment in which the light emitting device of the present invention is applied to an electroluminescence device will be described below with reference to FIG. The third embodiment differs from the first embodiment in the method for manufacturing an electroluminescent panel.

FIGS. 6A to 6C are cross-sectional views showing a method for manufacturing the electroluminescent panel 100B. 6A to 6C, the same elements as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 6A, the anode 2 is formed inside the substrate 1A. First, a transparent conductive film such as ITO is formed on the substrate 1A by a sputtering method or the like, and a photoresist is formed on the transparent conductive film. Then exposure,
The anode 2 is formed by patterning the photoresist by a developing process, etching the transparent conductive film using the patterned photoresist as a mask, and then removing the photoresist.

On the other hand, as shown in FIG. 6B, a cathode 5, a light emitting layer 4, and a hole transport layer 3 are formed inside the substrate 1B. First, an aluminum film is formed on the substrate 1B by an evaporation method or the like, and a photoresist is formed on the aluminum film. Thereafter, the photoresist is patterned by exposure and development steps, the aluminum film is etched using the patterned photoresist as a mask to form the cathode 5, and then the photoresist is removed. Next, the light emitting layer 4 is formed on the cathode 5 by using an evaporation method or the like. Further, the hole transport layer 3 is formed on the light emitting layer 4 by using an evaporation method or the like.

Next, as shown in FIG. 6 (c), the anode 2 and the hole transport layer 3 are superimposed and heat and pressure are applied.
Thermocompression bonding. By thus integrating the substrate 1A and the substrate 1B, the electroluminescent panel 100
B is formed. In this case, the glass transition temperature of the hole transport layer 3 is set lower than the glass transition temperatures of the other layers, and the other layers are affected by heating to a temperature near the glass transition temperature of the hole transport layer 3 in the thermocompression bonding step. , The hole transport layer 3 can be melted, and the anode 2 and the hole transport layer 3 can be thermocompression bonded.

In the third embodiment, similarly to the first embodiment, after the anode 2 is formed inside the substrate 1A and the cathode 5 is formed inside the substrate 1B, the substrates 1A and 1B are thermocompression-bonded. By doing so, an electroluminescent panel is manufactured. For this reason, a photolithography step can be used when forming the anode 2 and the cathode 5, and therefore, it is possible to cope with the case where the anode 2 or the cathode 5 must be formed at a fine pitch.

Regarding the correspondence between the third embodiment and the claims, the substrate 1B is the first substrate, the substrate 1A is the second substrate, the cathode 5 is the first electrode group, and the anode 2 is the second substrate. , Respectively. In addition, the hole transport layer 3 and the cathode 2 correspond to a pressure bonding layer of the first substrate and a pressure bonding layer of the second substrate, respectively.

[0049]

According to the present invention, the first electrode group is formed inside the first substrate, and the second electrode group is formed inside the second substrate. Since the two substrates are thermocompression bonded, photolithography technology can be used when forming the first electrode group and the second electrode group. Therefore, for example, the first electrode group and the second electrode group can be formed at a fine pitch.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an electroluminescent panel in which light-emitting elements according to a first embodiment are arranged in a matrix.

FIG. 2 is a diagram showing directions of an anode and a cathode.

FIG. 3 is a diagram showing a layer configuration of an electroluminescence panel.

4A and 4B are diagrams showing a method for manufacturing the electroluminescent panel shown in FIG. 1, wherein FIG. 4A is a cross-sectional view showing a layer formed on a substrate 1A, and FIG. 4B is a cross-sectional view showing a layer formed on a substrate 1B. FIG. 3C is a cross-sectional view showing the direction of thermocompression bonding between the substrate 1A and the substrate 1B.

5A and 5B are diagrams illustrating a method for manufacturing an electroluminescent panel in which light emitting elements according to the second embodiment are arranged in a matrix, and FIG. 5A is a cross-sectional view illustrating a layer formed on a substrate 1A; (B) is a sectional view showing a layer formed on the substrate 1B, and (c) is a sectional view showing the direction of thermocompression bonding between the substrate 1A and the substrate 1B.

FIGS. 6A and 6B are diagrams showing a method for manufacturing an electroluminescence panel in which the light emitting elements of the third embodiment are arranged in a matrix, and FIG. 6A is a cross-sectional view showing a layer formed on a substrate 1A; (B) is a sectional view showing a layer formed on the substrate 1B, and (c) is a sectional view showing the direction of thermocompression bonding between the substrate 1A and the substrate 1B.

[Explanation of symbols]

 Reference Signs List 1A substrate (first substrate, second substrate) 1B substrate (first substrate, second substrate) 2 anode (first electrode group, second electrode group) 3 hole transport layer 4 light emitting layer 5 cathode (First electrode group, second electrode group)

Claims (10)

[Claims] A first electrode group including a plurality of electrodes; a second electrode group including a plurality of electrodes; and a light emitting layer sandwiched between the first electrode group and the second electrode group. A step of forming the first electrode group and the light emitting layer on a first substrate; a step of forming the second electrode group on a second substrate; It is manufactured through a thermocompression bonding step of thermocompression bonding a first substrate on which an electrode group and the light emitting layer are formed, and the second substrate on which the second electrode group is formed. Light emitting element. 2. The compression bonding layer or the second compression bonding layer formed on the first substrate, which is thermocompression-bonded to each other in the thermocompression bonding step.
The light-emitting device according to claim 1, wherein the pressure-bonded layer formed on the substrate has heat-fusibility. 3. The light-emitting element according to claim 2, wherein the pressure-bonding layer has the lowest glass transition temperature among the layers constituting the light-emitting element.
The light-emitting device according to item 1. 4. A first electrode group including a plurality of electrodes, a second electrode group including a plurality of electrodes, and a light emitting layer interposed between the first electrode group and the second electrode group. A method for manufacturing a light emitting element comprising: a step of forming the first electrode group and the light emitting layer on a first substrate; a step of forming the second electrode group on a second substrate; A thermocompression bonding step of thermocompression bonding the first substrate on which the first electrode group and the light emitting layer are formed and the second substrate on which the second electrode group is formed. A method for manufacturing a light emitting device. 5. In the thermocompression bonding step, heating is performed to a temperature close to the glass transition temperature of a layer having a low glass transition temperature among the compression bonding layers of the first substrate or the compression bonding layers of the second substrate that are thermocompression bonded to each other. The method for manufacturing a light emitting device according to claim 4, wherein: 6. The thermocompression bonding step, wherein the first substrate and the second substrate are thermocompression-bonded in a state where the light emitting layer and the second electrode group are overlapped. Item 6. The method for manufacturing a light emitting device according to item 4 or 5. 7. A step of forming a hole transport layer on the second electrode group formed on the second substrate, wherein in the thermocompression bonding step, the light emitting layer and the hole transport layer are The method for manufacturing a light emitting device according to claim 4, wherein the first substrate and the second substrate are thermocompression-bonded in an overlapped state. 8. The method according to claim 8, further comprising: forming a hole transport layer on the light emitting layer formed on the first substrate. In the thermocompression bonding, the first electrode group and the hole transport layer are connected to each other. The method for manufacturing a light emitting device according to claim 4, wherein the first substrate and the second substrate are thermocompression-bonded in an overlapped state. 9. The method according to claim 4, wherein the first electrode group is formed using a photolithography technique.
9. The method for manufacturing a light-emitting element according to any one of items 8 to 8. 10. The method according to claim 4, wherein the second electrode group is formed by using a photolithography technique.