JP2009117278A - Manufacturing method of organic el display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an organic EL display device, which enables separated material painting and constitution for every pixel without positioning a substrate to the other members with high precision. <P>SOLUTION: In the manufacturing method of the organic EL display device in which a plurality of pixels composed of the lower part electrode 110, organic compound layers 112 (114, 116), and the upper electrode 113 (115, 117) are formed on the substrate 101, a thin film heat generator 107 corresponding at least to one of the pixels is formed on the substrate, and after a process of forming at least one organic compound layer 112, regarding the pixel in which the organic compound layer 112 is not necessary, a process of removing the organic compound layer 112 by flowing current to the thin film heat generator 107 and generating heat, and furthermore another organic compound layer and the upper part electrode are formed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an organic EL display device in which a plurality of pixels including a lower electrode, an organic compound layer, and an upper electrode are formed on a substrate. About.

  The organic EL display device currently under development is provided with a lower electrode on a substrate, a plurality of organic compound layers having functions related to charge injection, transport and recombination separated thereon, and an upper electrode. It is based on organic EL elements to be stacked.

  Multi-color display devices have also been developed.

  As a full-color flat display, the focus of development has shifted from a passive matrix method to an active matrix method in which a thin film transistor is provided for each pixel.

  In any case, it is common to perform color display by combining pixels of a plurality of colors with different materials and configurations of the organic compound layer depending on the pixels. A method of coating a low molecular material by vacuum vapor deposition using a metal mask and a method of coating a high molecular material by an ink jet method are known.

  Further, in recent years, a coating method for removing unnecessary portions using a laser disclosed in Patent Document 1 has also been proposed.

JP 2002-324672 A

  In any of the above-described methods, there is a problem that it is necessary to control the position with respect to the pixel with high accuracy.

  In other words, in the method of coating by vacuum deposition using a metal mask, it is necessary to align the position of the substrate and the mask, and at the same time, the accuracy of the mask itself is necessary, which causes a problem that increases costs and decreases yield. is there.

  Even with a method of coating a polymer material by the ink jet method, it is necessary to make the droplets land on the pixels with high accuracy, and at the same time, it is necessary to spread the droplets uniformly within the pixels. Is not always easy.

  The coating method for removing unnecessary portions using a laser also requires the laser position to be accurately controlled and moved. Furthermore, in this case, with respect to the intensity of the laser beam, sufficient energy is required to remove the organic compound layer, and it is necessary to suppress the intensity so as not to affect other members. This requires control of both the intensity distribution in the laser beam and the focal position, which is not always easy.

  The present invention can be manufactured by patterning of a normal film forming process and a photolithography process, and can be easily performed by a conventional manufacturing apparatus. It is an object of the present invention to provide a method for manufacturing an organic EL display device that enables different materials and configurations for each pixel without aligning the substrate with other members with high accuracy after pattern formation.

As means for solving the above problems, the present invention provides:
In a method for manufacturing an organic EL display device in which a plurality of pixels including a lower electrode, an organic compound layer, and an upper electrode are formed on a substrate,
After forming a thin film heating element corresponding to at least one of the pixels on the substrate and forming at least one organic compound layer,
For pixels that do not require the organic compound layer, the thin film heating element is energized to generate heat, and the organic compound layer is removed.
Furthermore, another organic compound layer and an upper electrode are formed.

  The present invention eliminates the need for high-accuracy alignment that has conventionally been required to vary the material and configuration of the organic compound from pixel to pixel. For this reason, it is possible to eliminate the difficulty of alignment due to the increase in size of the mother glass, and it is possible to manufacture high-definition pixels. This will enable significant improvement in cost and yield.

  The present invention can be applied to an active matrix system using thin film transistors and a passive matrix system using time division driving. Here, an active matrix method will be described as an example. In general, the structure of the display portion and the peripheral portion of the display device are not necessarily the same. Although the present invention relates to a display portion, it can also be applied to removal of an organic compound layer in a terminal portion or a connection portion.

  First, a large number of thin film transistors each including a channel layer, a gate oxide film, a gate electrode, a first protective film, an electrode layer, and a second protective film are formed in a matrix on a substrate such as glass. The surface at this time is covered with an insulating protective film except that the electrode of the thin film transistor connected to the lower electrode and the terminal portion of the extraction electrode for electrical connection outside the display device are exposed. These can be produced by performing film forming methods such as CVD, patterning by a series of photolithography processes, doping for valence electron control, annealing for crystallization and surface treatment as necessary. A control circuit may be simultaneously formed around the display portion.

  A first energization layer is formed thereon, and a pattern capable of energizing a thin film heating element corresponding to a pixel of one color is formed. It is preferable to provide a power supply unit that supplies power to the first conductive layer from the outside around the display device. A first interlayer insulating layer is formed thereon, a connection portion of the multilayer wiring to the first energization layer, a power supply portion of the first energization layer, a connection portion that needs to be connected to the electrode of the thin film transistor, The terminal portion of the extraction electrode is removed by etching.

  The production of the current-carrying layer and the interlayer insulating layer can be repeated as necessary, so that the conductive layer and the interlayer insulating layer can be provided in an arbitrary hierarchy in a multilayer wiring state. For example, in the case of color display with three colors, it is sufficient to provide two layers corresponding to two colors.

  On top of this, a thin film heating element and an energization layer in contact with the thin film heating element are sequentially laminated to form a thin film heating element corresponding to a pixel and a pattern capable of energizing the thin film heating element. This energizing layer is responsible for the connection between the energizing layer on the substrate side and the thin-film heating element, and at the same time has an opposite polarity to the energizing layer on the substrate side and is taken out around the display device in a direction perpendicular to the wiring on the substrate side. Is preferred.

  The thin film heating element can be obtained by removing a part of the energization layer. If the conductive layer is patterned first, a thin film heating element can be provided on the conductive layer.

  An interlayer insulating layer is further formed thereon, and portions that require electrical connection are removed by patterning. At this time, the outermost surface is the connection portion of the electrode of the thin film transistor connected to the lower electrode, the terminal portion of the extraction electrode for electrical connection to the outside of the display device, and the feeding portion of the energization layer that supplies electricity to the thin film heating element Is covered with an interlayer insulating layer. Note that the interlayer insulating layer may be patterned by etching a plurality of layers at the same position.

  A lower electrode is formed on the surface of the interlayer insulating layer and patterned. The lower electrode is electrically connected to the connection portion of the thin film transistor electrode through a through hole provided in the interlayer insulating layer. In some cases, an insulating or semiconductive element isolation film that covers a part of the lower electrode and defines the light emitting portion of the pixel may be provided.

  A plurality of first organic compound layers separated in function are provided uniformly on the display portion. It is preferable that the terminal part of the extraction electrode and the power feeding part of the energization layer are not formed by using a mask having a large opening in the entire display part. At this time, in addition to the organic light emitting layer, an organic compound layer that improves the injectability and transportability of charges (electrons or holes) from the lower electrode may be provided. In the organic compound layer, a low molecular compound may be provided by a vacuum deposition method, or a high molecular compound may be provided by an ink jet method or a coating method. A transfer method can also be used. Further, the first upper electrode may be provided in a region wider than the organic compound layer by sputtering or the like. The first upper electrode is connected to an extraction wiring connected to the outside.

  Thereafter, a thin film heating element corresponding to a pixel that does not require the first organic compound layer is energized to generate heat, and the first organic compound layer and the first upper electrode are removed simultaneously. Since the upper electrode is thin, it is destroyed and removed by evaporation of the organic compound layer in a short time. This removal process is possible in a vacuum atmosphere. Further, it is possible even in an atmospheric pressure of an inert gas atmosphere with dew point management. Note that the first upper electrode is not necessarily required, and if the two-color color or a narrow color reproduction range is sufficient, only the first organic compound layer may be used.

  The power supplied in the above removal step can be direct current, alternating current, or a pulse having an arbitrary waveform. For example, if the pixel size is about 80 μm × 20 μm and DC power is used, it can be removed at about 360 mW. Even a rectangular pulse of 1 msec can be removed with a power of about 490 mW. In particular, when the organic compound layer and the upper electrode are removed at the same time, it is preferable to instantaneously evaporate with a short pulse of 1 sec or less. If the power is increased, even a microsecond pulse can be removed. For example, although it is difficult in terms of power to generate heat simultaneously for 300,000 pixels, it is possible to generate heat sequentially by time-division driving using multilayer wiring. The energization can be supplied using a probe or the like by providing a power supply unit connected to the energization layer around the display device.

  If another layer configuration is required, the process of forming another organic compound layer and the process of removing electricity from the unnecessary pixel by energizing the thin film heating element to generate heat are repeated as necessary. Also at this time, like the above-described upper electrode, the upper electrode may be provided in a region wider than the organic compound layer by sputtering or the like. Here again, the upper electrode is connected to an extraction wiring connected to the outside.

  Depending on the application field of the display device, it is not always necessary to have a full color, and it may be sufficient to change the structure of the organic compound layer depending on the pixel. Further, in the full color display, the three primary colors can be displayed by forming and removing the organic compound layer and the upper electrode connected to the outside. In this case, since the organic compound layers of the respective colors are overlapped, it is slightly disadvantageous in driving conditions and light extraction, and therefore, it is preferable that the organic compound layers are manufactured from those having high luminous efficiency. However, in general, the light transmittance of the upper layer to be overlaid can be easily set to 90% or more, which is not a big problem.

  Moreover, in order to ensure the coverage of the removed edge part, it is preferable to overlap from a thin color. However, by making the portion to be removed by re-evaporation wider than the pixel portion where the lower electrode is exposed, the layer configuration of the pixel portion is not affected. That is, it is possible to provide an end portion of reevaporation on the element isolation film. In general, a short-circuit is likely to occur at the step portion, but even if conduction between the upper electrodes occurs at the end of the reevaporation portion, the short-circuit between the upper electrode and the lower electrode does not occur on the element isolation film. Furthermore, it is preferable that the end portion of the re-evaporating section is made gentle by performing heating conditions for re-evaporation or heating for additional annealing. Further, even if a break occurs at a part of the step, it is generally not broken at all around the re-evaporating part.

  In the present invention, the organic compound layer of the light emitting part can be formed and used by the most proven vacuum deposition method, compared to the method of transferring the organic compound layer by heat or the method of sublimation vapor deposition. The portion that does not contribute to light emission is heated and re-evaporated.

  Moreover, the heat conduction is in the direction of the film thickness, which is on the order of submicrons. The conduction of heat to the order of several tens of microns in the planar direction can be sufficiently ignored by design.

  Although this case is suitable for the top emission type that extracts light to the opposite side of the substrate, the essence of the invention can also be applied to the bottom emission type that extracts light to the substrate side, by designing the planar configuration appropriately. It is possible to implement. A metal or an alloy such as Al or AgMg can be used for the electrode opposite to the direction in which light is extracted. The lower electrode may be an anode or a cathode. The upper electrode may be an anode or a cathode.

  Further, an uppermost organic compound layer and an upper electrode are provided. In either case, an organic compound layer that improves the injectability and transportability of charges (electrons or holes) to the upper electrode may be provided separately from the organic light emitting layer.

  A sealing member made of glass or the like is adhered and sealed around the substrate except for the terminal portion of the extraction electrode. A hygroscopic agent may be provided avoiding the light emitting part in the sealed space, or the light emitting part may be provided if the hygroscopic agent is transparent. Further, a protective film made of SiON, SiN, or the like may be provided in multiple layers, or both the protective film and the sealing member may be provided. A polarizing plate may be provided on the surface of the sealing member or the protective film. The polarizing plate may be mechanically fixed in addition to partial adhesion or entire surface adhesion.

  Thus, the organic EL display device of the present invention can be completed. The above-described method eliminates the need for alignment that was conventionally required to vary the material and configuration of the organic compound depending on the pixel, eliminates the alignment difficulties associated with the increase in the size of the mother glass, and enables high-definition pixels. Production is also possible. This will enable significant improvement in cost and yield.

  Next, embodiments of the present invention will be described in more detail with reference to the drawings.

  FIG. 1 shows an example of an organic EL display device according to the present invention. FIG. 1 (a) is a conceptual diagram of a cross section, and FIG. 1 (b) is a conceptual diagram of a corresponding plane. The display area is enlarged and displayed for three subpixels. Actually, for example, the diagonal is about 3 inches, 640 pixels × 480 pixels, and the pitch of each subpixel is about 95 μm × 32 μm for the subpixels of three colors per pixel. It becomes. Originally, pixels are composed of sub-pixels of a plurality of colors. However, in order to avoid complicated explanation, sub-pixels are expressed as pixels in other explanation portions. In the case of about 27 inches diagonal and 1920 pixels × 1080 pixels, the subpixels of three colors per pixel are about 285 μm × 127 μm. Although the drive circuit is represented by one thin film transistor, it may actually be composed of a plurality of transistors, capacitors, and connection wirings. The control circuit outside the display area is not shown in FIG. The present invention can be applied regardless of the size and definition of the display device.

  FIG. 2 is a conceptual view of a more macroscopic plane of the organic EL display device. A driving circuit is provided in the display area 202 corresponding to the pixel, and a control circuit 203 is provided outside. A portion other than the terminal portion 204 of the extraction electrode is sealed with a sealing member 205. In the figure, reference numeral 206 denotes a sealed space other than the light emitting region.

In the present invention, a driving thin film transistor 102 is provided at each position of each pixel on the substrate 101 (201). First, a barrier layer (not shown) such as SiO ₂ , SiN, or SiON is formed with a thickness of 100 nm to 200 nm on a substrate 101 such as glass, quartz, or silicon by a plasma CVD method or the like.

  Again, a channel layer is formed by providing amorphous or microcrystalline silicon with a thickness of 30 nm to 150 nm by plasma CVD. It is polycrystallized by laser annealing or the like, and is patterned into a desired shape by photolithography.

A gate insulating film of SiO ₂ , SiN, SiON or the like is formed with a thickness of 50 nm to 200 nm, and a gate electrode layer made of Ta or W is formed thereon with a thickness of 50 nm to 200 nm by sputtering or the like, and is patterned. A configuration in which the gate electrode is provided under the channel layer is also possible.

The source and drain regions of the channel layer are separately doped with phosphorus, boron, etc., and then activated with laser light. Further, a protective film made of SiO ₂ , SiN, SiON or the like is provided thereon with a thickness of 100 nm to 1000 nm. Further, a connection opening is patterned on the protective film using a photolithography technique, an electrode layer made of Ti, Al, or the like is formed, and then patterned to provide a source electrode and a drain electrode. The film thickness is preferably 100 nm to 500 nm and a multilayer structure. Further, a protective film made of SiO ₂ , SiN, SiON or the like is provided thereon with a thickness of 100 nm to 1000 nm. Only the portion connected to the lower electrode of the organic EL element is etched.

  A plurality of thin film transistors may be formed per pixel, and wirings to capacitors and control circuits, connection terminals to the outside, and the like can be formed using a channel layer or an electrode layer. Peripheral circuits such as a shift register for control can also be manufactured simultaneously around the display area of the same substrate. The above example is a thin film transistor of a polycrystalline type, but it can also be an amorphous type, a microcrystalline type, or a transparent oxide semiconductor such as InGaZnO.

  Through the above steps, the thin film transistor 102 can be manufactured.

  The first energization layer 103 is formed by uniformly sputtering Ti or Al by sputtering or vacuum deposition, and patterned into a desired shape by photolithography.

A first interlayer insulating layer 104 is formed. SiOC by SiO ₂ , SiN, SiON, and other CVD films, resins such as acrylic and polyimide, SOG (spin-on-glass), TEOS (tetraethoxysilane), and VUV-CVD (photo CVD using vacuum ultraviolet light) Etc. are also available. The desired position is also etched for connection by photolithography.

  The second energization layer 105 is formed by uniformly sputtering Ti or Al by sputtering or vacuum deposition, and is patterned into a desired shape by photolithography.

  The second interlayer insulating layer 106 is formed in the same manner as the first interlayer insulating layer 104.

The thin film heating element 107 is made of TaN, HfB ₂ , Ti or the like, and then the third conductive layer 108 is made of Ti or Al uniformly by sputtering or vacuum deposition. The thin film heating element 107 and the third conductive layer 108 are simultaneously patterned into a desired shape by photolithography. Further, only the third conductive layer 108 at a position corresponding to the pixel is etched to produce a thin film heating element. In any case, it is preferable that the end of the pattern of the conductive layer is etched into a tapered shape.

  A third interlayer insulating layer 109 is formed. It is preferable to flatten the unevenness caused by the thin film transistor or the conductive layer. The degree of flattening is not particularly problematic with unevenness with an elevation difference of about 200 nm and an inclination angle of 30 ° or less, preferably 10 ° or less. Resins such as acrylic and polyimide, SOG (spin on glass), TEOS (tetraethoxysilane), and SiOC by VUV-CVD method (photo CVD method using vacuum ultraviolet light) can also be used. The desired position is also etched for connection by photolithography.

  Aluminum, chromium, silver, magnesium, tin oxide, zinc oxide, indium oxide, ITO, or the like is formed by a sputtering method or the like, and the lower electrode 110 is manufactured by a photolithography technique. A mixture or a laminated structure is also possible, and a reflective layer may be provided. The lower electrode itself may be used for connection with the thin film transistor, but another conductive layer may be provided for connection.

  Further, an element isolation film 111 may be formed by depositing amorphous silicon, SiN, polyimide, acrylic, or the like and patterning to cover the end of the lower electrode 110 and restrict the light emitting region.

  Thereafter, following a sufficient dehydration process such as heating in a vacuum, the first organic compound layer 112 is uniformly deposited on the display portion by a vacuum evaporation method or the like. The first organic compound layer 112 may be composed of a charge injection layer, a charge transport layer, and a light emitting layer (not shown). For example, Alq3 (host) and coumarin 6 (light emitting compound) are co-deposited (weight ratio 99: 1) as a green light emitting layer. The configuration of the organic compound layer is not limited to this, and when the organic compound layer is formed in a two-layer configuration by using a transport layer that also serves as a light emitting layer, or by providing a hole injection layer or an electron injection layer, For example, the compound layer may be composed of a plurality of layers of four layers and five layers.

For example, as a hole transporting substance, N, N′-diphenyl-N, N′-di (3-methylphenyl) -1,1′-diphenyl-4,4′-diamine (TPD) or N, N Triphenylamines typified by '-diphenyl-N, N'-dinaphthyl-1,1'-diphenyl-4,4'-diamine (NPD) and the like;
Heterocyclic compounds represented by N-isopropylcarbazole, biscarbazole derivatives, pyrazoline derivatives, stilbene compounds, hydrazone compounds, oxadiazole derivatives and phthalocyanine derivatives;
In the polymer system, polycarbonate, polystyrene derivatives, polyvinyl carbazole, polysilane, polyphenylene vinylene and the like having the above monomer in the side chain are preferable.

  As the hole injecting substance, copper phthalocyanine, aromatic starburst amine compound, polythiophene, alkoxy-substituted polyparaphenylene vinylene, polypyrrole derivative, or the like can be used.

In addition to anthracene, pyrene, and 8-hydroxyquinoline aluminum, the material of the light emitting layer is, for example, a bisstyryl anthracene derivative, a tetraphenylbutadiene derivative, a coumarin derivative, an oxadiazole derivative;
In the case of distyrylbenzene derivatives, pyrrolopyridine derivatives, perinone derivatives, cyclopentadiene derivatives, thiadiazolopyridine derivatives, and polymer systems, polyphenylene vinylene derivatives, polyparaphenylene derivatives, polythiophene derivatives, and the like can be used. Further, as the dopant added to the light emitting layer, rubrene, quinacridone derivatives, phenoxazone 660, DCM1, perinone, perylene, coumarin 540, diazaindacene derivatives and the like can be used as they are.

Examples of the electron transporting substance include 8-hydroxyquinoline aluminum, hydroxybenzoquinoline beryllium, 2- (4-biphenyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole (t-BuPBD). Oxadiazole derivatives such as
1,3-bis (4-t-butylphenyl-1,3,4-oxadizolyl) biphenylene (OXD-1), 1,3-bis (4-t-butylphenyl-1) of oxadiazole dimer system derivatives , 3,4-oxadizolyl) phenylene (OXD-7);
Examples include triazole derivatives and phenanthroline derivatives. Examples of electron injecting substances include nitro-substituted fluorenone derivatives, anthraquinodimethane derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives;
Heterocyclic tetracarboxylic anhydrides such as naphthaleneperylene, carbodiimide, fluorenylidenemethane derivatives, anthraquinodimethane derivatives and anthrone derivatives, oxadiazole derivatives;
Tris (8-quinolinol) aluminum, tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum, tris (2-methyl-8-quinolinol) aluminum;
In addition, there are Mg, Cu, Ga, Sn, Pb complexes other than aluminum and In. Metal-free or metal phthalocyanine, or those having a terminal substituted with an alkyl group, a sulfonic acid group or the like is also desirable. Moreover, what added the alkali metal and alkaline-earth metal to the organic material may be used. Further, an alkali metal compound or an alkaline earth metal compound can be provided with an extremely thin oxide, carbonate, fluoride, nitride, or the like.

The materials used for the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer can form each layer alone. As a polymer binder, polyvinyl chloride, polycarbonate, polystyrene, poly (N-vinylcarbazole), polymethyl methacrylate, polybutyl methacrylate, polyester, polysulfone, polyphenylene ether;
Solvent-soluble resins such as polybutadiene, hydrocarbon resins, ketone resins, phenoxy resins, polyurethane resins;
It can also be used by being dispersed in a curable resin such as phenol resin, xylene resin, petroleum resin, urea resin, melamine resin, unsaturated polyester resin, alkyd resin, epoxy resin, or silicone resin.

  A first upper electrode 113 connected to the outside is uniformly provided on the first organic compound layer 112.

  At this time, the state of FIG. 3A is obtained. A probe or the like is connected to the power feeding portion 121 of the energization layer to cause the thin film heating elements 307a and 307b to generate heat. The first organic compound layer 112 of the pixels 318 (118) and 319 (119) evaporates and can be removed together with the first upper electrode 113, and the state of FIG. 3B is obtained.

  Thereafter, the second organic compound layer 114 is uniformly deposited on the display portion by vacuum evaporation or the like. The second organic compound layer 114 may be composed of a charge injection layer, a charge transport layer, and a light emitting layer (not shown). For example, Alq3 (host) and DCM [4- (dicyanomethylene) -2-methyl-6 (p-dimethylaminostyryl) -4H-pyran] are co-evaporated (weight ratio 99: 1) as a red light emitting layer. Other materials can also be made from the materials described above.

  A second upper electrode 115 connected to the outside is uniformly provided on the second organic compound layer 114. The second upper electrode 115 can be made of a transparent conductive material such as tin oxide, zinc oxide, indium oxide, ITO, or IZO. It is preferable that the wiring for extraction which can be manufactured simultaneously with the electrode layer of the thin film transistor is connected to the outside of the display region and connected to the connection terminal.

  At this point, the state shown in FIG. 3C is obtained. A probe or the like is connected to the power feeding portion 121 of the energization layer to cause the thin film heating element 307b to generate heat. The second organic compound layer 114 of the pixel 319 (119) evaporates and can be removed together with the second upper electrode 115, and the state shown in FIG. 3D is obtained.

  Thereafter, the third organic compound layer 116 is uniformly deposited on the display portion by vacuum evaporation or the like. For example, perylene dye (1.0 vol%) and tris [8-hydroxyquinolinato] aluminum (Alq3) are co-evaporated as a blue light emitting layer. Other materials can also be made from the materials described above.

  A third upper electrode 117 connected to the outside is uniformly provided on the third organic compound layer 116. The third upper electrode 117 can be made of a transparent conductive material such as tin oxide, zinc oxide, indium oxide, ITO, or IZO. It is preferable that the wiring for extraction which can be manufactured simultaneously with the electrode layer of the thin film transistor is connected to the outside of the display region and connected to the connection terminal.

  At this time, the state shown in FIG. 3E is obtained. Note that the organic compound layer and the upper electrode are preferably not provided in the extraction terminal portion 122 or the feeding portion 121 of the energization layer by using a metal mask having a large opening in the display portion.

  Thereafter, glass 120 or the like provided with a digging is bonded in order to block oxygen, water, and the like from the outside. It is preferable to provide a hygroscopic material in the internal space. Further, a protective film such as silicon nitride or silicon nitride oxide may be deposited on the member manufactured up to the third upper electrode by a plasma CVD method or the like.

  Commercially available polarizing plates for display may be provided on these surfaces to complete the organic EL display device of the present invention. The polarizing plate may be mechanically fixed by a spring or the like in addition to partial adhesion or entire surface adhesion.

  In the conventional method, for example, it is not easy to manufacture a high-definition organic EL display device having a diagonal of 3 inches and VGA (640 pixels × 480 pixels). According to the present invention, such a high-definition display device is possible, and further, a smaller and higher-definition display device for a head-mounted display or the like can be manufactured.

  Examples of the organic EL display device of the present invention will be described.

<Example 1>
In Example 1, an organic EL display device corresponding to the conceptual diagram of FIG. 1 was produced. Two 3 inch diagonal display devices were fabricated simultaneously on a 6 inch φ glass substrate. 640 pixels × 480 pixels, and the pitch of each pixel is about 95 μm × 32 μm for three color sub-pixels. A conceptual diagram of the plane corresponds to FIG.

A barrier layer (not shown) was formed on the glass substrate 101 (201) by a plasma CVD method using SiH ₄ , NH _3, and H ₂ as source gases to a thickness of 200 nm. Next, a channel layer is also formed by providing amorphous silicon with a thickness of 50 nm by plasma CVD. Polycrystallized by laser annealing and patterned by photolithography. Channel layers of transistors for driving, switching, and control circuits can be formed. Next, a SiO ₂ gate insulating film with a thickness of 100 nm was formed, and Ta was deposited thereon with a thickness of 50 nm and Al with a thickness of 200 nm by sputtering or the like, and patterned to produce a gate electrode. Next, a portion other than the N region of the channel layer was protected with a resist, and phosphorus was doped. Next, the region other than the P region was protected with a resist, and boron was doped. After that, activation by laser light was performed. Further, a protective film made of SiN was provided thereon with a thickness of 500 nm. Further, a connection opening is patterned on the protective film using a photolithography technique to form a two-layer electrode layer composed of 100 nm of Ti and 300 nm of a TiAl alloy, and patterned to form a source electrode and a drain electrode. Capacitor electrodes and connection terminals 122 were provided.

  The first conductive layer 103 was formed by uniformly laminating Ti with a thickness of 10 nm and Al with a thickness of 200 nm by sputtering, and patterned into a desired shape by a photolithography technique. The end portion was tapered by about 30 ° using wet etching. At this time, the first energization layer 103 has a pattern capable of energizing the thin film heating element corresponding to the red pixel 118.

  A first interlayer insulating layer 104 is formed. SiN was deposited to a thickness of 300 nm by a CVD method, and a desired position was etched for connection by a photolithography technique.

  Similarly to the first energization layer 103, the second energization layer 105 was formed by uniformly laminating Ti and Al by sputtering, and was patterned into a desired shape by photolithography. The end portion was tapered by about 30 ° using wet etching. At this time, the second energization layer 105 has a pattern capable of energizing the thin film heating element corresponding to the blue pixel 119.

  A second interlayer insulating layer 106 was formed in the same manner as the first interlayer insulating layer 104.

  The thin film heating element 107 was manufactured by using TaN and adjusting the thickness to 10 nm and the sheet resistance to 350Ω. Subsequently, the third current-carrying layer 108 was produced by sputtering Al uniformly to a thickness of 200 nm. The thin film heating element 107 and the third conductive layer 108 were simultaneously patterned into a desired shape by photolithography. Further, only the third conductive layer 108 at a position corresponding to the pixel was etched to produce a thin film heating element. The end portion was tapered by about 30 ° using wet etching.

  The third energization layer 108 is connected to the first and second energization layers through the etched portion of the interlayer insulating layer. Further, a power feeding portion is provided around the display area in a direction orthogonal to the extraction direction as indicated by reference numeral 108 in FIG.

  A third interlayer insulating layer 109 is formed. Since it is preferable to flatten the unevenness due to the thin film transistor and the current-carrying layer, SiOC was formed to a thickness of 500 nm by the VUV-CVD method (photo CVD method using vacuum ultraviolet light). Again, a desired position was dry-etched using CF4 for connection by photolithography. The degree of flattening was uneven with an elevation difference of about 200 nm and an inclination angle of about 15 °. Sufficient dehydration was performed by heating to 300 ° C. in vacuum.

  A 50 nm thick AlSi film and a 100 nm ITO film were stacked by sputtering or the like, and a lower electrode 110 was fabricated by photolithography.

  A 300 nm SiN film was formed and patterned to form an element isolation film 111 that covered the end of the lower electrode 110 and restricted the light emitting region. The end portion was tapered by about 20 ° using wet etching.

  Thereafter, following a sufficient dehydration treatment such as heating in vacuum, the first organic compound layer 112 was uniformly deposited by a vacuum evaporation method using a metal mask having a large opening in the display portion. The organic compound layer 112 was formed by laminating a hole transport layer (not shown), a green light emitting layer, and an electron injection layer. The hole transport layer was made of αNPD. The green light emitting layer was prepared by co-evaporation (weight ratio 99: 1) of Alq3 (host) and coumarin 6 (light emitting compound). The electron injection layer was prepared by co-evaporation of lithium fluoride (0.9 vol%) and a phenanthroline compound represented by Chemical Formula 1.

  On the first organic compound layer 112, a first upper electrode 113 connected to the outside was uniformly provided by sputtering at a thickness of 100 nm using IZO. Using an opened metal mask, it was made wider than the organic compound layer up to the connection with the outside.

  At this point, the state of FIG. 3A was obtained. A probe or the like was connected to the power feeding portion 121 of the energization layer, and the thin film heating elements 307a and 307b were caused to generate heat. A power of 490 mW (28 V 17.5 mA) was applied with a 1 msec pulse per pixel. The first organic compound layer 112 of the pixels 318 (118) and 319 (119) was evaporated and could be removed together with the first upper electrode 113, and the state shown in FIG. 3B was obtained.

  Thereafter, the second organic compound layer 114 was deposited uniformly on the display portion by a vacuum evaporation method or the like using a metal mask having a large opening. The second organic compound layer 114 was composed of a hole transport layer (not shown), a red light emitting layer, and an electron injection layer. Alq3 (host) and DCM [4- (dicyanomethylene) -2-methyl-6 (p-dimethylaminostyryl) -4H-pyran] were co-evaporated (weight ratio 99: 1) as a red light emitting layer. The hole transport layer and the electron injection layer used the same thing as a green pixel.

  On the second organic compound layer 114, a second upper electrode 115 connected to the outside was uniformly provided by sputtering with IZO at a thickness of 100 nm. Using an opened metal mask, it was made wider than the organic compound layer up to the connection with the outside.

  At this point, the state shown in FIG. 3C was obtained. A probe or the like was connected to the power feeding portion 121 of the energization layer, and the thin film heating element 307b was heated. A power of 490 mW (28 V 17.5 mA) was applied with a 1 msec pulse per pixel. The second organic compound layer 114 of the pixel 319 (119) evaporates and can be removed together with the second upper electrode 115, and the state of FIG. 3D is obtained.

  Thereafter, the third organic compound layer 116 was deposited uniformly on the display portion by vacuum evaporation using a metal mask having a large opening. The same materials as green and red were used for the hole transport layer and the electron injection layer. For the blue light-emitting layer, perylene dye (1.0 vol%) and tris [8-hydroxyquinolinate] aluminum (Alq3) were co-evaporated.

  On the third organic compound layer 116, a third upper electrode 117 connected to the outside was uniformly formed by sputtering with IZO at a thickness of 100 nm. Using an opened metal mask, it was made wider than the organic compound layer up to the connection with the outside. At this point, the state shown in FIG. 3E was obtained.

  Thereafter, glass 120 or the like provided with a digging in order to shut off oxygen and water from the outside was bonded. A hygroscopic material made of zeolite was provided in the internal space.

  Commercially available polarizing plates for display were provided on these surfaces to complete the organic EL display device of the present invention. When operated, full color display was possible.

<Example 2>
In Example 2, a passive matrix type two-color organic EL display device corresponding to the conceptual diagram of FIG. 4 was produced.

  Four 2 inch diagonal display devices were simultaneously fabricated on a 6 inch φ glass substrate 401. 160 pixels × 1200 pixels, and the pitch of each pixel is about 254 μm × 127 μm for two-color subpixels.

  The first conductive layer 402 was formed by uniformly laminating Ti with a thickness of 10 nm and Al with a thickness of 200 nm by sputtering, and patterned into a desired shape by a photolithography technique. The end portion was tapered by about 30 ° using wet etching. At this time, the first energization layer 402 has a pattern capable of energizing the thin film heating element corresponding to the red pixel 412.

  A first interlayer insulating layer 403 was produced. SiN was deposited to a thickness of 300 nm by a CVD method, and a desired position was etched for connection by a photolithography technique.

  The thin film heating element 404 was formed using TaN with a thickness of 10 nm, and then the second conductive layer 405 was formed with Al uniformly with a thickness of 300 nm by sputtering. The thin film heating element 404 and the second conductive layer 405 were simultaneously patterned by a photolithography technique. Further, only the second conductive layer 405 at a position corresponding to the pixel was etched to produce a thin film heating element.

  A second interlayer insulating layer 406 was produced. Polyimide was applied, and the desired position was etched for connection, also by photolithography.

  An Ag—Mg alloy was formed into a film by a sputtering method or the like, and a lower electrode 407 was produced by a photolithography technique. Further, a polyimide film was formed and patterned to form an inversely tapered element isolation film 408 that covers the end portion of the lower electrode 407 and restricts the light emitting region.

  Thereafter, heating was performed at 180 ° C. in vacuum, and the first organic compound layer 409 was uniformly deposited on the display portion by a vacuum evaporation method. Note that the first organic compound layer 409 is an electron-transporting light-emitting layer, and Alq3 (host) and coumarin 6 (light-emitting compound) were co-deposited (weight ratio 99: 1) as a green light-emitting layer.

  A probe or the like was connected to the power feeding portion 414 of the energization layer, and the thin film heating element 404 was caused to generate heat. A DC power of 30 V and 160 mA per pixel was applied for about 1 sec. The first organic compound layer 409 of the pixel 412 was evaporated and could be removed.

  Subsequently, the second organic compound layer 410 and the second upper electrode 411 were uniformly provided. As the second organic compound layer 410, red Alq3 (host) and DCM [4- (dicyanomethylene) -2-methyl-6 (p-dimethylaminostyryl) -4H-pyran] were co-evaporated (weight ratio 99: 1). . A hole transport layer was laminated thereon with αNPD. The second upper electrode 411 can be made of an ITO transparent conductive material.

  The organic compound layer and the upper electrode were not provided by using a metal mask having a large opening in the display portion in the extraction terminal portion 415 or the feeding portion 414 of the energization layer.

  Thereafter, a glass 413 provided with a digging in order to shut off oxygen, water, and the like from the outside was bonded. A hygroscopic material was provided in the internal space.

  When operated, multicolor display from red to yellow was possible.

It is the conceptual diagram which expanded and showed an example of the organic electroluminescent display apparatus of this invention. It is the conceptual diagram which showed the plane of an example of the whole organic electroluminescence display of this invention. It is a conceptual diagram of the preparation procedure of the organic electroluminescence display of this invention. It is the conceptual diagram which expanded and showed the cross section of another example of the organic electroluminescent display apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Substrate 102 Thin film transistor 103 1st electricity supply layer 104 1st interlayer insulation layer 105 2nd electricity supply layer 106 2nd interlayer insulation layer 107a Thin film heating element 107b corresponding to a red pixel Thin film heating element corresponding to a blue pixel 108 Third conductive layer 109 Third interlayer insulating layer 110 Lower electrode 111 Element isolation film 112 First organic compound layer (green)
113 First upper electrode 114 Second organic compound layer (red)
115 Second upper electrode 116 Third organic compound layer (blue)
117 Third upper electrode 118 Red pixel 119 Blue pixel 120 Sealing member 121 Power feeding portion 122 of conductive layer Extraction electrode terminal portion 201 Substrate 202 Display region 203 Control circuit 204 Connection terminal 205 Sealing member 206 Other than light emitting region Sealing space 307a Thin film heating element 307b corresponding to red pixel Thin film heating element 318 corresponding to blue pixel Red pixel 319 Blue pixel 401 Substrate 402 First conductive layer 403 First interlayer insulating layer 404 Thin film heating Body 405 Second conductive layer 406 Second interlayer insulating layer 407 Lower electrode 408 Element isolation film 409 First organic compound layer (green)
410 Second organic compound layer (red)
411 Upper electrode 412 Red pixel 413 Sealing member 414 Current-carrying power feeding portion 415 Extraction terminal portion

Claims (6)

In a method for manufacturing an organic EL display device in which a plurality of pixels including a lower electrode, an organic compound layer, and an upper electrode are formed on a substrate,
After forming a thin film heating element corresponding to at least one of the pixels on the substrate and forming at least one organic compound layer,
For pixels that do not require the organic compound layer, the thin film heating element is energized to generate heat, and the organic compound layer is removed.
Furthermore, another organic compound layer and an upper electrode are formed, The manufacturing method of the organic electroluminescence display characterized by the above-mentioned. In a method for manufacturing an organic EL display device, a plurality of pixels including a lower electrode, an organic compound layer, and an upper electrode connected to the outside are formed on a substrate.
After forming a thin film heating element corresponding to at least one of the pixels on the substrate and forming the first organic compound layer and the first upper electrode connected to the outside,
A step of removing the first organic compound layer and the first upper electrode by energizing the thin film heating element to generate heat for a pixel that does not require the first organic compound layer and the first upper electrode. Carried out,
Furthermore, the manufacturing method of the organic EL display device characterized by forming an organic compound layer and the upper electrode connected to the exterior. In a method for manufacturing an organic EL display device, a plurality of pixels including a lower electrode, an organic compound layer, and an upper electrode connected to the outside are formed on a substrate.
After forming a thin film heating element corresponding to at least one of the pixels on the substrate and forming the first organic compound layer and the first upper electrode connected to the outside,
A step of removing the first organic compound layer and the first upper electrode by energizing the thin film heating element to generate heat for a pixel that does not require the first organic compound layer and the first upper electrode. Carried out,
Subsequently, forming another organic compound layer and another upper electrode connected to the outside,
The thin film heating element is energized to generate heat, and the process of removing the organic compound layer and the upper electrode of unnecessary pixels is repeated as necessary.
A method of manufacturing an organic EL display device, further comprising forming an uppermost organic compound layer and an uppermost upper electrode connected to the outside.   The method for manufacturing an organic EL display device according to claim 1, wherein the organic compound layer includes a plurality of layers.   5. The organic EL display device according to claim 1, wherein an energization layer for energizing the thin film heating element is provided in a state of multilayer wiring on the substrate side from the lower electrode. Production method.   6. The method of manufacturing an organic EL display device according to claim 1, wherein the thin film heating element is formed wider than the pixel and the organic compound layer is removed wider than the pixel.

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