JPH11273869A - Organic luminous element and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display element which is high in reliability by a relatively simple element structure without taking complicated measures for sealing it up. SOLUTION: An organic luminous element comprising, at least a positive electrode layer, a luminous layer 5 made of an organic material and a negative electrode layer, having a positive electrode 2 and a negative electrode 6 at least one of which is transparent, and emitting light from the luminous layer 5 by injecting a current thereinto, is turned into an element to act as a display element of high reliability and high definition by making up its pixels or segments for display out of a plurality of minute current injection area 3' groups neighboring each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-reliability, high-definition, low-cost color display device overcoming the drawbacks of conventional organic light-emitting devices, and a method of manufacturing the same.

[0002]

2. Description of the Related Art With the development of a highly information-oriented multimedia society, the development of flat display devices with low power consumption and high image quality has been activated. Non-emissive liquid crystal display elements have established their position with the feature of low power consumption, and their applications to portable information terminals and the like have been further enhanced.

On the other hand, since the self-luminous display element is not affected by external light, it replaces a conventional CRT and further has a CRT.
Electroluminescent displays are being actively developed to realize large-screen displays and ultra-high-definition displays, which are difficult to achieve.

[0004] Tan et al. Adhere and form a hole-injecting electrode layer, an organic hole-transporting layer, an organic electron-transporting light-emitting layer, and an electron-injecting electrode layer on a substrate, thereby forming an organic light-emitting layer at low voltage. Proposed EL (Reference: CWTang et al.
Appl. Phys. Lett. Vol. 51, p. 913 (1987)), and recently, ELDs using such devices as character display devices and image display devices.
Has been prototyped.

An outline of a conventional organic EL device proposed by Tan et al. Is shown in FIG. An anode 112 made of a transparent conductive thin film having a relatively large ionization potential such as indium tin oxide (ITO) and easy to inject holes is formed on a glass substrate 111. Next, a hole transport layer 114 and an electron transporting light emitting layer 115 are sequentially formed on almost the entire surface thereof. A cathode 116 is formed on the surface of the metal layer having a relatively low work function such as a silver magnesium alloy (AgMg) and is easy to inject electrons. Further, the surface is covered with a protective layer 117,
Further, a glass container 118 is provided on the element side, and the inside thereof is filled with an inert gas 120.

The light-emitting layer having an electron-transporting property generally has a lower work function than a metal. However, by using a metal having a low work function such as an AgMg alloy as a cathode, injection and transport of electrons can be relatively performed. Can be easily realized. Further, since the hole transport layer has a relatively large ionization potential, injection and transport of holes are relatively performed by using a material having a large ionization potential such as gold (Au) or indium tin oxide (ITO) as the anode. Can be easily realized. Then, by applying a positive DC voltage to the anode with respect to the cathode, holes are injected from the anode (ITO) 112 into the hole transport layer, and electrons are injected from the cathode 116 into the electron transporting light emitting layer. Further, in the light emitting layer near the junction between the hole transporting layer and the electron transporting layer (light emitting layer), these are combined to form excitons and emit light 121. This emission is observed through the transparent electrode and the substrate. Needless to say, light emission can also be obtained by bonding the hole transporting organic light emitting layer and the electron transporting organic layer and injecting and transporting holes and electrons.

This light emitting principle is similar to an inorganic light emitting diode formed of gallium arsenide or the like, in which electrons and holes are injected into a compound semiconductor having a PN junction, and the electrons and holes near the junction are formed. It can correspond to light emission due to recombination. The electron transport layer can be compared with an N-type compound semiconductor, and the hole transport layer can be compared with a P-type compound semiconductor.

However, in the organic EL device, the organic EL medium used for the charge injection layer and the light emitting layer and the low work function material used as the cathode have low moisture resistance and oxidation resistance, so that the reliability is low and the operating life of the device is low. In addition to that, there still remains a problem with the shelf life. For example, simply leaving the element in the air causes a non-light-emitting point called a black point to occur, deteriorating the display quality, and furthermore, a phenomenon occurs in which the light-emission does not occur due to expansion over time. there were.

Although the cause of the occurrence of black spots remains unclear, dust adhering to the substrate surface at the time of film formation, dust adhering after film formation, or at least local defects such as pinholes. Becomes the nucleus, the organic layer or the cathode layer is peeled off, and the peeled off part becomes a new defect, and oxygen and water repeatedly affect it,
Eventually, in most cases, the black point expands around the initial point defect portion to its peripheral portion.

[0010] In order to prevent the occurrence of black spots, it is conceivable to completely eliminate defects generated at the time of manufacturing. However, since the thickness of the organic thin film is as thin as about 0.1 μm, dust having a size substantially smaller than this is required. It is considered that it is almost impossible to eliminate a defect by removing the like. Therefore, attempts have been made to coat the surface of the element with a resin or the like so that the organic layer and the cathode layer are not directly exposed to moisture or oxygen after the formation of the thin film. However, in general, resins that can be used because organic solvents are low in solvent resistance are limited in addition to resins that can be used, and there is almost no resin that can sufficiently secure moisture resistance in practical use. As described above, it was necessary to enclose the entire device in a completely sealed container.

However, encapsulating the entire device in a completely sealed container not only increases the manufacturing cost, but also increases the thickness and weight of the display device. There was a big hindrance.

[0012]

As described above, it is difficult to realize a highly reliable display with conventional organic light-emitting devices, and it is extremely difficult to implement a low-cost color display. Met.

An object of the present invention is to overcome the drawbacks of the conventional organic light-emitting device and realize a highly reliable, high-definition display device and a low-cost color display device.

[0014]

The present invention comprises at least an anode layer, a light-emitting layer made of an organic substance, and a cathode layer,
And at least one of the anode or the cathode is transparent,
Further, in an organic light emitting device in which light is emitted from a light emitting layer by current injection, a pixel or segment for display is divided into a plurality of minute current injection regions adjacent to each other. It is.

The present invention also provides a process for forming a current block layer on a surface of a first electrode formed on a substrate so as to surround a plurality of minute regions into which current is injected, and an organic thin film including a light emitting layer. And a process of forming a second electrode.

[0016]

The invention according to claim 1 of the present invention comprises at least an anode layer, a light emitting layer made of an organic substance, and a cathode layer, and at least one of the anode and the cathode is transparent; Further, in the organic light emitting device in which light is emitted from the light emitting layer by current injection, a pixel or segment for display is constituted by a plurality of minute current injection region groups adjacent to each other. Thus, a high-reliability and high-definition display device overcoming the drawbacks of the conventional organic light-emitting device and a low-cost color display device can be obtained.

According to a second aspect of the present invention, there is provided at least an anode layer, a hole transport layer made of an organic substance, an electron transporting light emitting layer made of an organic substance, and a cathode layer. An organic light-emitting device in which one is transparent and light is emitted from a light-emitting layer by current injection, wherein pixels or segments for display are constituted by a plurality of minute regions adjacent to each other. Can display with high reliability and high definition.

According to the third aspect of the present invention, a high-definition display is possible with an organic light-emitting element characterized in that the size of the minute region is 50 microns or less.

According to a fourth aspect of the present invention, there is provided an organic light-emitting device in which a plurality of minute regions to which a current is injected are separated by a current non-injection region formed by an insulating layer disposed at a boundary between the minute regions. An organic light-emitting device with high reliability without the black spots of deterioration spreading can be obtained.

The invention described in claim 5 or 6 is:
A plurality of minute regions into which current is injected are separated by a current non-injection region formed by a cathode having a large work function arranged at a boundary portion of the minute region. Electron transport separated by a current non-injection region formed by a small ionization potential anode located at the boundary of When the light-emitting layer is made of a light-emitting layer and the current non-injection region is formed by the hole transport layer, the luminous efficiency of the device is expected to be improved.

The invention according to any one of claims 7 to 10 is characterized in that the plurality of minute regions into which current is injected are provided between the anode layer and the hole transport layer at the boundary of the minute regions. A plurality of minute regions, which are separated by a current non-injection region formed by an organic layer or are injected with a current, are composed of a hole transport layer divided into minute regions and a light emitting layer formed uniformly, and A non-injection region is formed by a light emitting layer, or a plurality of minute regions into which current is injected are formed by a hole transporting organic layer disposed between a cathode layer and an electron transport layer at a boundary of the minute region. When separated by the current non-injection region, a highly reliable and high definition organic light emitting device can be obtained.

Next, any of the organic display devices manufactured by the manufacturing method according to any one of claims 11 to 16 has the above-mentioned effects, and a high-reliability, high-definition, low-cost display device can be obtained. can get.

[0023]

Next, specific examples of the present invention will be described.

(Embodiment 1) Hereinafter, a light emitting device according to a first embodiment of the present invention will be described with reference to FIG.

In FIG. 1, reference numeral 1 denotes a glass substrate. A transparent anode (row electrode) 2 made of indium tin oxide for injecting holes is linearly divided on the surface thereof, and an oxide having a plurality of micropores formed on at least the surface of the anode layer and adhered to the surface of the anode layer. Triphenyldiamine (TPD [N, N'-bis (3-methylphenyl)-) uniformly formed on the surface of the insulating layer (current blocking layer) 3, the anode and the insulating layer made of silicon.
(1,1'-biphenyl) -4,4'-diamine]), and a uniformly formed aluminum quinolinol complex (Alq [tris (8-hydroxyquino) aluminium]). An organic light-emitting layer 5 having an electron transporting property, a cathode layer (column electrode) 6 made of a silver-magnesium alloy for injecting electrons, and a silicon oxide layer 7 as a protective layer are sequentially formed.

When an electric field is applied between the anode 2 and the cathode 6, holes and electrons are injected from the respective electrodes into the organic light emitting layer, but holes are not injected into the portion where the current blocking layer 3 is formed. The current is blocked, and light is emitted from a plurality of minute regions corresponding to the minute current injection region 3 'on which this layer is not formed. And a transparent anode 2 and a glass substrate 1
And the light 8 is emitted. In this organic light-emitting device, the light-emitting portion is formed of a plurality of minute regions adjacent to each other, so that it is observed to the naked eye that light is emitted almost uniformly.

Next, a method for manufacturing the organic light emitting device of the present invention will be described with reference to FIG. (A) 21 is a glass substrate. ITO on glass substrate
(Transparent electrode) 22 'is uniformly formed.

(B) The transparent electrode is divided into row electrodes 22 having a period of 500 μm and a width of 490 μm by photolithography.

(C) A silicon oxide layer (SiO 2) 23 is formed on the entire surface as an insulating layer. (D) A plurality of micro holes 2 arranged adjacent to each other in the silicon oxide layer on the transparent electrode by photolithography
Form 3 '. Here, the arrangement period of the micro holes is 50 μm, and the size of the micro holes is about 45 μm square.

(E) Next, triphenyldiamine (TPD [N, N'-bis (3-methylphenyl)-(1,1'-biph
enyl) -4,4'-diamine]) and an aluminum quinolinol complex (Alq [tris (8-hydroxyquino)).
aluminum]) is sequentially formed by vapor deposition.

(F) A column electrode 2 made of a silver-magnesium alloy for injecting electrons and having a period of 500 μm and a width of 400 μm
6 is formed by a mask evaporation method.

(G) Finally, a silicon oxide film is formed on the protective film 37.
As vapor deposition. In the organic light-emitting device formed as described above, the size of the display pixel is substantially determined by the width of the row electrode and the column electrode, and is about 500 μm square. However, as described above, since the current injection region is divided into micropore regions of 50 μm or less, one pixel is also divided into a plurality of (80) light emitting units. However, since the individual dimensions of the divided light emitting portions are minute dimensions smaller than the limit that can be identified by the naked eye and are adjacent to each other, it is observed by the naked eye that light is emitted almost uniformly.

Also in the organic light emitting device of the present invention, it is impossible to completely remove defects such as dust in the manufacturing process, as in the conventional case. Occurs. However, the current non-injection area where current is not injected (current block area)
There is no spread of sunspots. Therefore, even if a black spot is generated and expanded, the spread is limited to a small light emitting region of a size and does not affect an adjacent light emitting portion. Therefore, the black point does not expand to a size of 50 μm or more, and the black point does not expand to the entire light emitting portion. As a result, there is no significant deterioration in luminance due to the enlargement of the non-light emitting region as in the related art.

In addition, a black spot in a non-light-emitting portion occurs in a specific minute light-emitting region.
It is not observed with the naked eye because it is limited to submicron. Of course, when black spots are simultaneously generated in a plurality of light-emitting portions adjacent to each other, a non-light-emitting portion is observed with the naked eye, but this probability is extremely small and does not pose a practical problem.

As described above with reference to the embodiments, in the present invention, it is possible to realize a highly reliable display element with a relatively simple element configuration without taking complicated sealing means as in the prior art. Is possible.

In the above embodiment, the arrangement period of the minute area is set to 5
The size was set to 0 μm and the size was set to 45 μm, but it is not necessarily limited to this, and both may be smaller. Further, the electrode structure has a matrix shape in which a plurality of row electrodes and a plurality of column electrodes are orthogonal to each other, but may have a segment shape including a plurality of divided electrodes and a common electrode.

On the other hand, in the above embodiment, the hole transport layer made of TPD and the Alq
Although a light emitting layer having an electron transporting property is used, the material is not necessarily limited to this. Further, the light emitting layer may be interposed between the organic layer having an electron transporting property and the organic layer having a hole transporting property, and different organic dye materials may be added in order to enhance the luminous efficiency. Further, in addition to the carrier transport layer and the light emitting layer, a hole injection layer, an electron injection layer, and the like may be added.

In this embodiment, silicon oxide is used as the current block layer for dividing the light emitting region into minute regions. However, the present invention is not limited to this, and another insulating material may be used.

Although ITO is used for the anode and a silver-magnesium alloy is used for the cathode as the electrode material, it is obvious that the present invention is not necessarily limited to this.

(Embodiment 2) In the first embodiment, the plurality of minute regions into which the current is injected are formed by a current non-injection region constituted by an insulating layer (current block layer) arranged at the boundary between the minute regions. Although the organic light emitting device is characterized in that it is separated, the plurality of minute regions into which the current is injected are a current non-injection region formed by a cathode having a large work function arranged at the boundary of the minute region. The device of the present invention can be realized even with a configuration separated by the above.

Hereinafter, a light emitting device according to a second embodiment of the present invention will be described with reference to FIG.

In FIG. 3, reference numeral 31 denotes a glass substrate.
An anode (row electrode) 32 for injecting linearly divided holes and a triphenyldiamine (TPD [N,
N'-bis (3-methylphenyl)-(1,1'-biphenyl) -4,4'-diamin
e]), a hole transporting layer 34 composed of an aluminum quinolinol complex (Alq [tris (8-hydroxyquino) aluminium]), and a cathode in a small region composed of a silver-magnesium alloy for injecting electrons. An (electron injection electrode layer) 36, a silver electrode (column electrode) 38 having a work function larger than that of the silver-magnesium alloy and formed in a row, and a silicon oxide layer 37 as a protective layer are sequentially formed. By applying an electric field between the row electrode and the column electrode, the light-emitting layer 3
Electrons are injected into 5.

However, the low work function cathode 36 is not formed and electrons are not injected at the interface where the silver electrode 38 and the light emitting layer 35 are in direct contact. Therefore, in the present embodiment, a plurality of minute regions into which current is injected are separated by a current non-injection region formed by a cathode having a large work function arranged at the boundary of the minute region.

As a result, current injection can be performed only in a plurality of minute regions adjacent to each other on which the cathode 36 is formed, and only a plurality of minute regions arranged adjacent to each other at a predetermined interval in the light emitting layer. Emits light. Then, light is emitted through the transparent electrode 32 and the glass substrate 31.

Next, a method for manufacturing the organic light emitting device of the present invention will be described with reference to FIG. (A) ITO 42 'is deposited on the glass substrate 41.

(B) Next, the substrate is divided into row electrodes 42 having a period of 500 μm and a width of 490 μm by photolithography.

(C) Liphenyldiamine (TPD [N, N'-bis (3-methylphenyl)-(1,1'-biphenyl)-
4,4′-diamine]) and a hole transport layer 44 composed of aluminum quinolinol complex (Alq [tris (8-hydroxyquino) alum).
organic light emitting layer 45 made of indium]).

(D) Then, a metal electrode layer 46 made of a silver-magnesium alloy for injecting electrons is formed by vapor deposition through a metal mask in which fine holes are formed. Here, the arrangement period of the micro holes is 50 μm, and the size of the micro holes is about 45 μm square.

(E) Silver is vapor-deposited by mask and the cycle is 500 μm,
A column electrode having a width of 400 μm is formed. (F) Finally, a silicon oxide film is deposited as a protective film 47 by vapor deposition.

In the organic light emitting device formed as described above, since one pixel is divided into a plurality of adjacent minute light emitting portions, it is observed that the light is emitted almost uniformly to the naked eye.

Also, in the organic light emitting device of the present invention,
A black spot occurs in the light emitting portion of a specific minute area. However, the black spot does not spread to adjacent minute light-emitting portions that are substantially separated by the interface formed by the metal layer having a large work function. Therefore, the black spot does not expand to a size of 50 μm or more, and does not expand to the entire light emitting portion.

(Embodiment 3) In the second embodiment, a plurality of minute regions into which current is injected are separated by a current non-injection region formed by a cathode having a large work function disposed at the boundary of the minute region. The light emitting element of the configuration is shown,
The present invention is applicable to a light emitting device having a configuration in which the plurality of minute regions into which the current is injected are separated by a current non-injection region formed by an anode having a small ionization potential arranged at the boundary of the minute region. An element can be realized.

Hereinafter, a light emitting device according to a third embodiment of the present invention will be described with reference to FIG. In FIG. 5, reference numeral 51 denotes a glass substrate. On its surface, a transparent electrode (row electrode) 52 for injecting linearly divided holes, and on its surface an aluminum metal layer 59 for dividing and surrounding a plurality of minute regions for hole injection, triphenyl Diamine (TPD [N, N'-bis (3-methylphenyl)-(1,1'-biphenyl)-
4,4′-diamine]) and a hole transport layer 54 composed of aluminum quinolinol complex (Alq [tris (8-hydroxyquino) alum).
An organic light emitting layer 55 made of indium]), a metal electrode layer (column electrode) 56 made of a silver-magnesium alloy for injecting electrons, and a silicon oxide layer 57 as a protective layer are sequentially formed.

By applying an electric field between the row electrode and the column electrode, the anode 5 in a minute region having a large ionization potential is formed.
Holes are injected from an interface between the hole transport layer 2 and the hole transport layer 54. However, holes are not injected at the interface where the metal layer 59 having a small ionization potential is formed.

Therefore, in this embodiment, a plurality of minute regions into which current is injected are separated by a current non-injection region formed by a metal layer having a small ionization potential disposed at the boundary between the minute regions. Has become.

As a result, current injection is possible only in a plurality of adjacent minute regions surrounded by the metal layer 59, and only a plurality of adjacent minute regions of the light emitting layer are arranged at a certain interval corresponding thereto. Emits light. Then, light is emitted through the transparent electrode 52 and the glass substrate 51.

Next, a method for manufacturing the organic light emitting device of the present invention will be described with reference to FIG. (A) ITO 62 ′ is deposited on a glass substrate 61.

(B) Next, the substrate is divided into row electrodes 62 by photolithography. (C) Aluminum 63 is formed on the entire surface.

(D) Then, an aluminum layer formed on the transparent electrode is formed by photolithography so that a plurality of micropores having a diameter of 50 μm or less are adjacent to each other.

(E) Triphenyldiamine (TPD [N, N'-bis (3-methylphenyl)-(1,1'-biph
enyl) -4,4′-diamine]) and a hole transport layer 64 composed of aluminum quinolinol complex (Alq [tris (8-hydroxyquin)).
o) An organic light emitting layer 65 of aluminum]) is sequentially formed by vapor deposition.

(F) A metal electrode layer (column electrode) 66 made of a silver-magnesium alloy for injecting electrons is formed by a mask evaporation method.

(G) Finally, a silicon oxide film is formed on the protective film 67.
As vapor deposition. In the organic light emitting device formed as described above, since one pixel is divided into a plurality of minute light emitting portions adjacent to each other, it is observed that light is emitted almost uniformly to the naked eye.

In the organic light emitting device of the present invention,
A black spot occurs in the light emitting portion of a specific minute area. However, the black spot does not spread further to the adjacent minute light emitting portions separated by the metal layer having a small potential. Therefore, the black spot does not expand to a size of 50 μm or more, and therefore does not expand to the entire light emitting portion.

On the other hand, in the above embodiment, Al is used as a metal material for blocking hole injection. However, the present invention is not limited to this. The ionization potential is higher than that of a hole injection electrode such as indium tin oxide. Any small material may be used.

(Example 4) In Examples 2 and 3,
The light emitting element has a configuration in which a plurality of minute regions into which current is injected are formed with a cathode material having a large work function or an anode material having a small ionization potential, respectively, in a minute region at the interface between the cathode or the anode and the organic layer. Alternatively, the light emitting layer or the hole layer may be formed by being divided into a plurality of minute regions.

Hereinafter, a light emitting device according to a fourth embodiment of the present invention will be described with reference to FIG. In FIG. 7, reference numeral 71 denotes a glass substrate. A transparent electrode (row electrode) 72 for injecting linearly divided holes is provided on the surface thereof.
And triphenyldiamine (TPD [N, N'-bis (3-methyl
phenyl)-(1,1'-biphenyl) -4,4'-diamine]), a hole transport layer 74, and an aluminum quinolinol complex (Alq [tris (8-hydroxyquino)) formed in a fine island shape. alumin
ium]) and a metal electrode layer (column electrode) made of a silver-magnesium alloy for injecting electrons.
76, and a silicon oxide layer 77 as a protective layer are sequentially formed. In the minute region where the light emitting layer is formed, the electron is injected into the light emitting layer by applying a negative voltage to the column electrode with respect to the row electrode, and the hole is injected into the hole transport layer. Recombination occurs in the light emitting layer in the region, and light is emitted from the light emitting layer in the minute region. Then, light is emitted through the transparent electrode 72 and the glass substrate 71.

On the other hand, in a region where only the hole layer is not provided with a light-emitting layer, no light emission occurs. In addition, since electrons are not directly injected into the hole layer from the cathode, the hole layer is not heated and the entire device is not heated. Does not adversely affect

Next, a method for manufacturing the organic light emitting device of the present invention will be described with reference to FIG. (A) ITO 82 ′ is deposited on a glass substrate 81.

(B) Divide into row electrodes 82 by photolithography. (C) Triphenyldiamine (TPD [N, N'-bis (3-methylphenyl)-(1,1'-biph
The hole transport layer 84 composed of enyl) -4,4'-diamine]) is uniformly formed.

(D) Next, the aluminum quinolinol complex (Al
q [tris (8-hydroxyquino) aluminium]) is vapor-deposited through a mask in which a plurality of micropores having a diameter of 50 μm or less are formed adjacent to each other.

(F) A metal electrode layer (column electrode) 86 made of a silver-magnesium alloy for injecting electrons is formed by a mask evaporation method.

(G) Finally, a silicon oxide film is formed on the protective film 87.
As vapor deposition. In the above embodiment, the light emitting layer is formed in an island shape.
It is obvious that the same effect can be obtained even if the hole transport layer is formed in an island shape.

(Embodiment 5) In Embodiment 4, a device in which a plurality of minute regions into which current is injected is divided into a light emitting layer or a hole layer into a plurality of minute regions is shown. The current non-injection region surrounding the minute region may be a hole transport layer formed in contact with the cathode or an electron transport layer formed in contact with the anode.

Hereinafter, a light emitting device according to a fifth embodiment of the present invention will be described with reference to FIG.

In FIG. 9, reference numeral 91 denotes a glass substrate.
A transparent anode (row electrode) 92 for injecting linearly divided holes on its surface and an aluminum quinolinol complex (Alq) for dividing and surrounding a plurality of minute regions for hole injection on its surface. [tris (8-hydroxyquino) aluminium]) electron transport layer 95 ', triphenyldiamine (TPD
[N, N'-bis (3-methylphenyl)-(1,1'-biphenyl) -4,4'-dia
mine]) and an aluminum quinolinol complex (Alq [tris (8-hydroxyquino) aluminium])
, A cathode (column electrode) 96 made of a silver-magnesium alloy for injecting electrons, and a silicon oxide layer 97 as a protective layer are sequentially formed.

When an electric field is applied between the anode 92 and the cathode 96, holes and electrons are injected from the respective electrodes into the organic light emitting layer, but in the portion where the electron transport layer 95 'is formed directly on the surface of the anode. The holes are not injected and the current is blocked,
Light is emitted from a plurality of minute regions corresponding to the minute current injection region where this layer is not formed. And a transparent anode 9
2 and the glass substrate 91 to emit light. In this organic light-emitting device, the light-emitting portion is formed of a plurality of minute regions adjacent to each other, so that it is observed to the naked eye that light is emitted almost uniformly.

Next, a method for manufacturing the organic light emitting device of the present invention will be described with reference to FIG. (A) An anode (ITO) 102 'is deposited on a glass substrate 101.

(B) Divide into row electrodes 102 by photolithography. (C) An aluminum quinolinol complex (Alq [tr] having a period of 50 μm and a width of 5 μm in the row direction by mask evaporation on the surface of the transparent electrode.
is (8-hydroxyquino) aluminium]) to form an organic electron transport layer 105 '.

(D) Similarly, an aluminum quinolinol complex (A) having a period of 50 μm and a width of 5 μm in the column direction by mask evaporation
An organic electron transport layer composed of lq [tris (8-hydroxyquino) aluminium]) is formed. As a result, an electron transport layer 105 'surrounding the plurality of micro holes arranged adjacent to each other is formed. The arrangement period of the micro holes is 50 μm, and the size of the micro holes is about 45 μm square.

(E) Further, triphenyldiamine (TPD [N, N'-bis (3-methylphenyl)-(1,1'-biph
enyl) -4,4′-diamine]) and an aluminum quinolinol complex (Alq [tris (8-hydroxyqu
ino) aluminum]) is sequentially formed by vapor deposition.

(F) A column electrode 1 made of a silver-magnesium alloy for injecting electrons and having a period of 500 μm and a width of 400 μm
06 is formed by a mask evaporation method.

(G) Finally, a silicon oxide film is formed on the protective film 10.
7 is formed by vapor deposition. In the above embodiment, the current blocking layer was formed by the electron transporting layer formed at the interface between the anode and the hole transporting layer, but the current blocking layer was formed by the hole layer formed at the interface between the cathode and the electron transporting layer. It is self-evident.

In the organic light-emitting devices shown in the second to fifth embodiments, the size of the display pixel is substantially determined by the width of the row electrode and the column electrode as in the first embodiment.
It is 0 μm square. However, the current injection region is 5
Each pixel is divided into a plurality of (80) light-emitting portions because it is divided into minute hole regions of 0 μm or less. However, since the light emitting portions are minute and are adjacent to each other, the light is observed to be almost uniformly emitted to the naked eye.

Also in the organic light emitting device of the present invention, it is impossible to completely remove defects such as dust in the manufacturing process as in the prior art. Occurs. However, the current non-injection area where no current is injected (current block area)
There is no spread of sunspots. Therefore, even if a black spot is generated and expanded, the spread is limited to the minute light emitting region and does not affect the adjacent light emitting portion. Therefore, the black spot does not expand to a size of 50 μm or more, and does not expand to the entire light emitting portion. As a result, there is no significant deterioration in luminance due to the enlargement of the non-light emitting region as in the related art. In addition, although a non-light-emitting area black spot occurs and expands in a specific minute light-emitting area, even if the non-light-emitting area expands, the area is limited to 50 μm or less and is not visually observed. Of course, when black spots are simultaneously generated in a plurality of light-emitting portions adjacent to each other, a non-light-emitting portion is observed with the naked eye, but this probability is extremely small and does not pose a practical problem.

In the above embodiment, the arrangement period of the minute regions is set to 50 μm and the size is set to 45 μm. However, the present invention is not limited to this, and both may be smaller. Further, the electrode structure has a matrix shape in which a plurality of row electrodes and a plurality of column electrodes are orthogonal to each other, but may have a segment shape including a plurality of divided electrodes and a common electrode.

On the other hand, in the above embodiment, the hole transport layer made of TPD and the Alq
Although a light emitting layer having an electron transporting property is used, the material is not necessarily limited to this material. Further, the light emitting layer may be interposed between the organic layer having an electron transporting property and the organic layer having a hole transporting property, and different organic materials may be added to enhance luminous efficiency.

Further, in addition to the carrier transport layer and the light emitting layer, a hole injection layer, an electron injection layer and the like may be added. Further, in this embodiment, silicon oxide is used as the current block layer for dividing the light emitting region into minute regions. However, the present invention is not limited to this, and another insulating material may be used.

As the electrode material, a transparent ITO is used for the anode and a metal electrode made of a silver-magnesium alloy is used for the cathode. However, it is obvious that the present invention is not necessarily limited to this.

[0089]

As described above with reference to the embodiments, in the present invention, a highly reliable display element can be realized with a relatively simple element structure without taking complicated sealing means as in the prior art. It is possible to As shown in the above embodiment,
The present invention overcomes the drawbacks of the conventional organic electroluminescent device and provides a highly reliable and high-definition self-luminous flat panel display device that has never been seen before, and can be expected to have an extremely large effect in industry.

[Brief description of the drawings]

FIG. 1 is a sectional view of a light emitting device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a manufacturing process of the light emitting device according to the first embodiment of the present invention.

FIG. 3 is a sectional view of a light emitting device according to a second embodiment of the present invention.

FIG. 4 is a diagram showing a manufacturing process of the light emitting device according to the second embodiment of the present invention.

FIG. 5 is a sectional view of a light emitting device according to a third embodiment of the present invention.

FIG. 6 is a diagram showing a manufacturing process of the light emitting device according to the third embodiment of the present invention.

FIG. 7 is a sectional view of a light emitting device according to a fourth embodiment of the present invention.

FIG. 8 is a diagram showing a manufacturing process of the light emitting device according to the fourth embodiment of the present invention.

FIG. 9 is a sectional view of a light emitting device according to a fifth embodiment of the present invention.

FIG. 10 is a diagram showing a manufacturing process of the light emitting device according to the fifth embodiment of the present invention.

FIG. 11 is a diagram showing a cross-sectional structure of a conventional organic light emitting device.

[Explanation of symbols]

 1, 21, 31, 41 Glass substrate 2, 22, 32, 42 Anode (ITO) 3, 23 Insulating layer 4, 24, 34, 44 Hole transport layer 5, 25, 35, 45 Light emitting layer 6, 26, 36 , 46 Cathode (AgMg) 7, 27, 37, 47 Protective layer 3 'Current injection region 38, 48 Electrode (Ag) 51, 61 Glass layer 52, 62 Anode (ITO) 54, 64 Hole transport layer 55, 65 Light emission Layers 56, 66 Cathode (AgMg) 57, 67 Protective layer 59, 68 Metal layer (Al) 71, 81 Glass substrate 72, 82 Anode (ITO) 74, 84 Hole transport layer 75, 85 Light emitting layer 76, 86 Cathode ( AgMg) 77, 87 Protective layer 91, 101 Glass substrate 92, 102 Anode (ITO) 94, 104 Hole transport layer 95 ', 105' Electron transport layer 95, 105 Light emitting layer 96, 106 Cathode (AgMg) 97, 107 Protective layer

Claims (16)

[Claims] 1. An organic light-emitting device comprising at least an anode layer, a light-emitting layer made of an organic substance, and a cathode layer, wherein at least one of the anode and the cathode is transparent, and light is emitted from the light-emitting layer by current injection. An organic light-emitting device, wherein a pixel or a segment for display is constituted by a plurality of minute current injection region groups adjacent to each other. 2. At least one of an anode layer, a hole transporting layer made of an organic substance, an electron transporting light emitting layer made of an organic substance, and a cathode layer, and at least one of the anode and the cathode is transparent. 2. The organic light emitting device according to claim 1, wherein in the organic light emitting device in which light is emitted from the light emitting layer by current injection, pixels or segments for display are composed of a plurality of minute regions adjacent to each other. . 3. The organic light emitting device according to claim 1, wherein the size of the minute region is 50 μm or less. 4. The method according to claim 1, wherein the plurality of minute regions into which the current is injected are:
2. The organic light emitting device according to claim 1, wherein the organic light emitting device is separated by a current non-injection region formed by an insulating layer disposed at a boundary portion of the minute region. 5. The method according to claim 1, wherein the plurality of minute regions into which the current is injected are:
2. The organic light emitting device according to claim 1, wherein the organic light emitting device is separated by a current non-injection region formed by a cathode having a large work function disposed at a boundary portion of the minute region. 6. The plurality of minute regions into which current is injected,
2. The organic light emitting device according to claim 1, wherein the organic light emitting device is separated by a current non-injection region formed by an anode having a small ionization potential disposed at a boundary of the minute region. 7. The plurality of minute regions into which current is injected,
3. The organic light-emitting device according to claim 2, comprising a hole-transporting layer and a light-emitting layer having an electron-transporting property divided into minute regions, and wherein the current non-injection region is formed by the hole-transporting layer. 8. The plurality of minute regions into which current is injected,
3. The organic light emitting device according to claim 2, wherein the organic light emitting device is separated by a current non-injection region formed by an electron transporting organic layer disposed between the anode layer and the hole transporting layer at the boundary of the minute region. element. 9. The plurality of minute regions into which current is injected,
3. The organic light-emitting device according to claim 2, comprising a hole transport layer divided into minute regions and a uniformly formed light-emitting layer, wherein the current non-injection region is formed by the light-emitting layer. 10. The non-current-injected region formed by a hole-transporting organic layer disposed between a cathode layer and an electron-transporting layer at the boundary of the minute region, wherein the plurality of minute regions to be subjected to current injection are formed. The organic light-emitting device according to claim 2, wherein the organic light-emitting device is separated. 11. A process for forming a current block layer in a shape surrounding a plurality of minute regions into which current is injected on a surface of a first electrode formed on a substrate, and forming an organic thin film including a light emitting layer. A method for manufacturing an organic light emitting device, comprising a process and a process of forming a second electrode. 12. A process for forming an insulating film on a substrate having an anode or a cathode formed on the substrate, a process for forming a plurality of minute holes adjacent to each other in the insulating film, and a light emitting layer substantially uniformly on the surface of the substrate. And a process for forming a cathode or an anode on the surface of the organic film. 13. A process for forming an organic thin film including a light emitting layer substantially uniformly on a surface of a substrate on which an anode or a cathode is formed, wherein a plurality of metals having a lower work function than a cathode are formed on the surface of the organic layer. A method for manufacturing an organic light-emitting device, comprising: a process of forming a minute region; and a process of forming a cathode or an anode on the surface of the organic layer and the low work function metal layer. 14. A process of forming a conductive layer having a higher ionization potential on a surface of a substrate on which an anode or a cathode is formed in a plurality of minute regions, and further comprising an organic layer including a light emitting layer substantially uniformly on the surface. A method for manufacturing an organic light emitting device, comprising a process of forming a thin film and a process of forming a cathode or an anode on the surface of the organic layer. 15. A process of forming an organic thin film including at least a hole transport layer and a light emitting layer on a surface of a substrate on which an anode or a cathode is formed, and hole transport while leaving a plurality of minute regions on the surface. A method for manufacturing an organic light emitting device, comprising: a process of forming a layer; and a process of forming a cathode or an anode on the surface of the organic layer. 16. A process for forming an electron transporting layer while leaving a plurality of minute regions on a surface of a substrate on which an anode or a cathode is formed, and further comprising an organic layer including at least a hole transporting layer and a light emitting layer on the surface substantially uniformly. A method for manufacturing an organic light emitting device, comprising a process of forming a thin film and a process of forming a cathode or an anode on the surface of the organic layer.