JP2013054876A - Manufacturing method of organic light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem in which, in a manufacturing method using a peeling process to peel off a layer formed on a release layer by dissolving the release layer, there exists a possibility to cause a patterning defect due to adhesion of a film fragment drifting in a removing solvent to a surface of a substrate after patterning, since the peeled-off film fragment is insoluble in the removing solvent dissolving the release layer.SOLUTION: By forming a release layer continuously over a plurality of light emitting parts, a formed pattern of the release layer, ie., a size of a film to be peeled off, is made larger. Thus, an adhesion provability of the peeled-off film fragment to a surface of a substrate is reduced and the film fragment is easier to be removed even if it adheres, thereby an occurrence of a patterning defect is suppressed.

Description

  The present invention relates to a method for manufacturing an organic light-emitting device, which includes a step of patterning an organic compound layer using photolithography. In particular, the present invention relates to a manufacturing method including a step of patterning an organic compound layer using a release layer formed in a predetermined pattern by photolithography.

  Patent Document 1 discloses a method for manufacturing an electroluminescent element in which an organic light emitting layer is patterned using photolithography. A specific manufacturing method is as follows. First, a first light emitting layer that is insoluble in a photoresist material is formed on a substrate, a photoresist layer is formed on the first light emitting layer, and the photoresist layer remains in a portion where the first light emitting portion is formed. Then, the photoresist layer is patterned. After removing the first light emitting layer in the region where the photoresist layer does not remain, a second light emitting layer is formed on the substrate having the first light emitting layer and the photoresist layer remaining on the surface thereof. After that, a peeling solution is brought into contact with the remaining photoresist layer and peeled off together with the second light emitting layer formed thereon, thereby forming a first light emitting part and a second light emitting part.

  Further, in Patent Document 2, it is difficult to peel from the organic compound layer by providing a release layer having excellent peelability between the organic compound layer and the resist layer in the same manufacturing method as Patent Document 1. In addition, a method of manufacturing an electroluminescent element that can easily peel off unnecessary layers such as a photoresist layer is disclosed.

Japanese Patent No. 4578026 Japanese Patent No. 4544811

  As in Patent Documents 1 and 2, in the step of peeling the layer formed on the patterned photoresist layer or release layer together with the photoresist layer or release layer, a solution (peeling solution) that dissolves these layers Contact to dissolve. As the stripping solution, a solution that selectively dissolves the photoresist layer or the stripping layer is used. Therefore, since the film piece peeled off together with the dissolution of the photoresist layer or the peeling layer is not dissolved in the peeling liquid, it may float in the peeling liquid and adhere to the surface of the substrate after patterning to cause a patterning defect.

  Patent Documents 1 and 2 do not describe anything about the specific pattern of the organic compound layer, but when the size of the film to be peeled off during patterning is small and many, the peeled film pieces are The rate at which patterning defects occur due to adhesion to the surface of the substrate increases.

  The present invention reduces the probability that a peeled film piece adheres to the surface of a substrate by increasing the size of the peeling layer forming pattern, that is, the size of the peeled film, and once removed, it is removed later. An object is to suppress the occurrence of patterning defects.

In order to solve the above problems, a method for manufacturing an organic light-emitting device according to the present invention includes:
Forming a first organic compound layer including at least a first light emitting layer on a substrate on which a plurality of first electrodes are formed according to a plurality of light emitting portions;
Selectively forming a release layer continuous over a portion of the plurality of light emitting portions on the first organic compound layer;
Removing the portion of the first organic compound layer where the release layer is not formed;
Forming a second organic compound layer including at least a second light emitting layer on the portion from which the first organic compound layer has been removed and the release layer;
The base on which the second organic compound layer is formed is brought into contact with a release liquid that selectively dissolves the release layer, and both the release layer and the second organic compound layer formed on the release layer are combined. And a step of removing.

  According to the present invention, since the release layer is continuously formed on the plurality of light emitting portions, the release layer is selectively dissolved by contacting with the release liquid, and the film pieces such as the second organic compound layer to be peeled are removed. The size can be increased. Therefore, compared with the case where the organic compound layer is patterned for each first electrode, the number of film pieces to be peeled can be reduced, and the peeled film pieces can be prevented from adhering to the substrate. As a result, it is possible to suppress leakage, short circuit, non-light emission, and the like caused by the peeled film piece adhering to the patterned substrate, and to obtain an organic light emitting device with good performance.

The schematic diagram of the organic light-emitting device produced with the manufacturing method of this invention. The figure explaining an example of the manufacturing method of this invention. The figure explaining another example of the manufacturing method of this invention. The figure which shows the formation pattern of the organic compound layer concerning the manufacturing method of this invention. The figure which shows another formation pattern of the organic compound layer concerning the manufacturing method of this invention. The figure which shows another another formation pattern of the organic compound layer concerning the manufacturing method of this invention. The figure which shows the comparison pattern of the formation pattern of the organic compound layer concerning this invention.

  A method for manufacturing an organic light emitting device according to the present invention will be described with reference to the drawings. Note that well-known or publicly-known techniques in the technical field can be applied to parts that are not particularly illustrated or described. In addition, the embodiment described below is an example of a method for manufacturing a light emitting device according to the present invention, and is not limited thereto.

  FIG. 1A is a schematic plan view of an organic light-emitting device formed by the method for manufacturing an organic light-emitting device according to the present invention, and FIG. 1B is a schematic cross-sectional view taken along line XI-XII in FIG. It is. First, the configuration of the organic light emitting device will be described.

  The substrate 10 is provided with a light emitting region 12 in which a plurality of light emitting portions are formed. Outside the light emitting region 12, an external connection terminal 15 is provided for receiving power and signals from the outside. FIG. 1 shows only a state in which a part of the external connection terminal 15 is connected to the second electrode, but the other part of the external connection terminal 15 is provided on a circuit layer (not shown) provided on the base 10. Electrically connected.

  In the light emitting region 12, a plurality of first electrodes (lower electrodes) 21 to 23 are formed for each light emitting portion in the row direction and the column direction. Each first electrode is electrically connected to a circuit layer (not shown). A first organic compound layer 31 including at least a first light emitting layer is formed on the first electrode 21. A second organic compound layer 32 including at least a second light emitting layer is formed on the first electrode 22. Are provided with a third organic compound layer 33 including at least a third light-emitting layer. The first light-emitting layer, the second light-emitting layer, and the third light-emitting layer are layers that emit different colors, and when a layer that emits red (R), green (G), and blue (B) is assigned to each light-emitting layer. Full color can be displayed. On the 1st-3rd light emitting layer, the 2nd electrode (upper electrode) 70 which continues over a some light emission part is formed. Hereinafter, a stacked body including a first electrode, a second electrode, and an organic compound layer sandwiched between the first electrode and the second electrode provided in each light emitting portion is referred to as a light emitting element. The light emitting element can emit light according to a signal input to the circuit layer via the external connection terminal 15. Note that the first electrode may also be provided in common for the plurality of light emitting units. In other words, a plurality of light emitting units may be provided on one first electrode. The second electrode is connected to the external connection terminal 15 through the contact portion 11 and the wiring layer 14.

  Since a light-emitting element using an organic compound layer is significantly deteriorated by moisture, a sealing layer 90 that covers the light-emitting element and prevents moisture from entering the light-emitting region 12 from the outside is provided. Since organic materials such as the organic compound layer easily penetrate moisture, the organic compound layer is removed so as to surround the light emitting region 12 in order to prevent moisture from entering the light emitting region from the outside through the organic compound layer. It is preferable to cut off the moisture intrusion route. The sealing layer 90 is formed of a highly moisture-proof material. Instead of the sealing layer 90 in FIG. 1, a glass cap or the like may be fixed to the substrate 10 with an adhesive having low moisture permeability, and moisture from the outside may be suppressed.

  Hereinafter, a method for manufacturing an organic light emitting device according to the present invention will be described in detail with reference to FIG.

  First, the base 10 on which the plurality of first electrodes 21 to 23 are formed according to the light emitting unit is prepared. The substrate 10 can be an insulating substrate made of glass, synthetic resin, or the like, or a conductive substrate whose surface is covered with an insulating film such as a silicon oxide film, a silicon nitride film, or a silicon nitride oxide, or a semiconductor substrate. However, in the case of a bottom emission type light emitting device, a transparent substrate is used. A drive circuit including a known transistor (Tr), a planarization film, a pixel separation film, and the like are provided on the base 10 as necessary.

  The first electrode is an anode or a cathode, and when used as an anode, a material having a large work function is used so that holes can be easily injected. In the case of a top emission type organic light emitting device, from the viewpoint of increasing light extraction efficiency, the first electrode is made of a metal layer such as Al, Ag, Au, Pt, or Cr, or an alloy film or a laminated film made of these materials. It is preferable to use a light reflective layer. A laminated film in which a transparent conductive layer such as indium tin oxide or indium zinc oxide is formed on these light reflective layers is also preferable.

  The first electrode is formed by first forming a conductive layer on the entire surface of the substrate 10 using a vacuum film formation method such as sputtering or vapor deposition, and patterning the conductive layer for each light emitting portion by known photolithography. . After the formation of the first electrode, a partition layer for partitioning the light emitting part may be formed between the first electrodes as necessary to define the light emitting area of each light emitting part. The partition layer can be formed using an insulating organic material such as photosensitive polyimide or an insulating inorganic material such as silicon nitride.

  An organic compound layer is formed on the entire substrate surface on which the first electrode is formed. The organic compound layer includes at least a light emitting layer, and includes functional layers such as a hole injection layer, a hole transport layer, a hole block layer, an electron block layer, an electron transport layer, and an electron injection layer as necessary. May be.

  The organic light-emitting device of the present invention is a light-emitting device that includes a plurality of light-emitting portions that emit different colors, and is capable of multicolor display. Therefore, it is necessary to selectively form an organic compound layer including a different light emitting layer in each light emitting portion depending on the light emission color. However, there are cases where functional layers other than the light emitting layer can be shared between light emitting portions having different emission colors. In such a case, any layer formed after patterning each light emitting layer may be formed as a common layer across a plurality of light emitting portions emitting different colors.

  For the light-emitting layer, triarylamine derivatives, stilbene derivatives, polyarylenes, aromatic condensed polycyclic compounds, aromatic heterocyclic compounds, aromatic heterocondensed ring compounds, metal complex compounds, etc., and single or composite oligos thereof For example, a known low molecular weight material can be used. In addition, a polyparaphenylene vinylene derivative, a polythiophene derivative, a polyparaphenylene derivative, a polysilane derivative, a polyacetylene derivative, a polyfluorene derivative, a polyvinyl carbazole derivative, or a polymer obtained by polymerizing the above-described low molecular weight material is used. You can also The low molecular weight material can be formed by a vacuum deposition method, and the high molecular material can be formed by a coating method such as a spin coating method or an ink jet method.

  Hereinafter, in order of formation, they are referred to as a first organic compound layer, a second organic compound layer, and a third organic compound layer, and the organic layers included in the respective layers are referred to as a first light emitting layer, a second light emitting layer, and a third light emitting layer. Call. Each organic compound layer can be similarly formed.

  Next, the first organic compound layer 31 formed first on the first electrode is patterned using photolithography. A photoresist material 51 is applied to the entire substrate on which the first organic compound layer 31 is formed to form a photoresist layer 51, and then exposed and developed to form a photoresist layer on the plurality of first electrodes 21. 51 is selectively formed. At this time, if the first organic compound layer 31 is affected by the solvent contained in the photoresist material or the developer of the photoresist layer, the photoresist layer is directly formed on the organic compound layer. Therefore, it is necessary to protect the first organic compound layer from a solvent or the like. The case where the photoresist layer cannot be formed directly on the holding compound layer will be described later. First, the case where the photoresist layer can be formed directly on the organic compound layer will be described.

[When a photoresist layer can be formed directly on the organic compound layer]
FIG. 2 is a diagram illustrating a manufacturing method in the case where a photoresist layer can be directly formed on an organic compound layer. FIG. 2A shows the step of forming the first organic compound layer 31 on the first electrodes 21 to 23 described above. A photoresist layer 51 is formed on the first organic compound layer 31 (FIG. 2B). The photoresist material may be selected from known photosensitive materials, and can be applied by a known method such as a spin coating method, a dipping method, or a spray coating method. The substrate 10 on which the photoresist layer is formed is irradiated with ultraviolet light 60 or the like through a photomask 61 having a desired pattern using an exposure apparatus (FIG. 2C). Then, it is immersed in a developing solution and patterned so that a photoresist layer remains on the first organic compound layer formed on the first electrode 21 (FIG. 2D).

  Using the remaining photoresist layer 51 as a mask, the first organic compound layer 31 is patterned by dry etching (FIG. 2E). For the dry etching, a method of removing by chemical reactivity such as oxygen or fluorine-based gas or a method of physically removing using argon gas or the like can be used depending on the material formed on the substrate. By this dry etching process, the first organic compound layer 31 in the region where the photoresist layer 51 does not remain is removed, and the surfaces of the first electrodes 22 to 23 are exposed. In dry etching, the film can be removed almost perpendicularly to the substrate, so that the inclination angle of the end portion of the patterned first organic compound layer can be formed at an angle close to 90 °. As a result, high-definition patterning can be realized as compared with other methods.

  The photoresist layer 51 left as a mask is similarly dry etched when the first organic compound layer is dry etched. Therefore, in order to protect the organic compound layer 31 on the first electrode 21, the photoresist layer is preferably formed with a sufficiently large film thickness, and is preferably about 2 to 5 μm after coating.

  Subsequently, the second organic compound layer 32 is formed on the entire substrate 10 with the photoresist layer 51 remaining (FIG. 2F). When the second organic compound layer 32 is formed by a coating method, a condition that the solvent of the second organic compound layer material does not affect the first organic compound layer 31 and the photoresist layer 51, and a stripping solution for the photoresist layer 51 It is necessary to satisfy the condition that the solubility of the second organic compound layer 32 is small. However, when the second organic compound layer 32 is formed by a vacuum deposition method, the choice of materials can be made because the condition that the solvent of the second organic compound layer material does not affect the first organic compound layer 31 and the photoresist layer 51 can be ignored. Is preferable because it increases. The same applies to the third organic compound layer 33.

  The substrate 10 on which the second organic compound layer 32 is formed is immersed in a stripping solution that dissolves the photoresist layer 51, and the second organic compound layer 52 formed on the photoresist layer 51 is removed together with the removal of the photoresist layer 51. Is peeled off (FIG. 2G). Here, although the photoresist layer 51 also serves as a peeling layer for peeling the second organic compound layer 32, a layer having a surface of several tens to several hundreds nm of the photoresist layer 51 is not easily dissolved by dry etching. It has become. In order for the photoresist layer 51 to also serve as a release layer, it is better that a layer that is easily dissolved exists under a layer in which the photoresist layer 51 after dry etching is difficult to dissolve, and the film thickness after dry etching is good. Is preferably 1 μm or more. Furthermore, the solubility of the first organic compound layer and the second organic compound layer in the stripping solution of the photoresist layer 51 needs to be 1/10 or less, more preferably 1/50 or less of the photoresist layer 51. In order to promote the dissolution, it is preferable to increase the solubility by increasing the temperature of the stripping solution, or to promote the penetration into the photoresist layer 51 by applying ultrasonic vibration. In this way, the organic compound layer 32 peeled together with the layer in which the photoresist 51 is difficult to dissolve is in close contact with the surface of the photoresist layer 51 even after peeling, and thus becomes a large film piece without being finely broken. .

  In addition, the film piece formed of the layer 51 in which the photoresist 51 is hardly dissolved and the second organic compound layer 32 is hardly dissolved in the stripping solution, and thus floats in the stripping solution. In order to prevent the film pieces of the second organic compound layer from adhering to the surface of the patterned substrate 10, it is preferable to circulate the stripping solution or apply ultrasonic vibration. The substrate 10 after peeling off the photoresist layer 51 and the second organic compound layer 32 on the photoresist layer 51 is preferably washed with a pure water shower or the like in order to remove surface deposits.

  At this time, deposits on the substrate 10 can be reduced depending on the pattern of the photoresist layer. For example, as shown in FIG. 7, when the photoresist layer for patterning the first organic compound layer 31 is an individual pattern formed for each first electrode 21, the photoresist layer is peeled by the area and number of the first electrodes 21. The size and number of film pieces of the second organic compound layer 32 are determined. For example, when a 3-inch full-color display device having a resolution of VGA (pixel number: 640 × 480) is manufactured as the organic light emitting device, the first electrodes 21 to 23 have a size of about 30 μm × 100 μm and are each 640 ×. 480 = 307200 are formed. Therefore, since 307200 film pieces of the second organic compound layer 32 having a size of 30 μm × 100 μm are generated by the peeling process, the film pieces adhere to the surface of the substrate 10 and the incidence of patterning defects is very high. Become.

  Therefore, in the present invention, the formation pattern of the photoresist layer 51, that is, the first organic compound layer 31 is continuously formed on the plurality of light emitting portions, so that the peeled piece of the second organic compound layer is enlarged. At the same time, reduce the number of occurrences. If the number of peeled pieces of the second organic compound layer itself decreases, the probability of adhering to the surface of the substrate 10 can also be reduced. Moreover, even if it adheres to the substrate surface at the time of peeling, the removal force received from the cleaning liquid is increased by the amount of the second organic compound layer that is increased in the subsequent cleaning process such as shower cleaning, and the probability of removal is also increased. .

  4 and 5 partially show examples of formation patterns of specific organic compound layers according to the present invention. 4A shows a pattern in which each organic compound layer is continuous in one row of the first electrode, and FIG. 5A shows a pattern in which the first organic compound layer 31 is continuous over two rows of the first electrode 21. It is. (B) of each figure has shown the pattern of the photoresist layer formed when patterning a 1st organic compound layer, and the 2nd organic compound layer 32 of the magnitude | size equivalent to this pattern peels with a photoresist layer. Will do. The production method of the present invention is not limited to these specific examples, and various patterns can be used as long as the organic compound layer is continuously formed across a plurality of light emitting portions.

  After removing the second organic compound layer 32 on the photoresist layer 51, a photoresist layer 52 is newly formed on the entire surface of the substrate 10 provided with the first and second organic compound layers (FIG. 2). (H)). The formation pattern of the second organic compound layer 32 can be determined by the formation pattern of the photoresist layer 52. The new photoresist layer 52 can also be formed in the same manner as the previously formed photoresist layer 51. Then, a newly formed photoresist layer 52 is used by using a photomask 52 so as to remain on the first organic compound layer 31 and the second organic compound layer 32 formed on the first electrode 22. Patterning is performed (FIGS. 2 (i) to (j)). Similar to the patterning of the first organic compound layer 31, the second organic compound layer is also formed in a pattern continuous to the plurality of first electrodes 22. For each of the pattern examples of FIGS. 4 and 5, (c) shows the formation pattern of the photoresist layer when the second organic compound layer 32 is patterned. The photoresist layer 52 for patterning the second organic compound layer 32 is larger than the photoresist layer 51 for patterning the first organic compound layer 31, and the number thereof is reduced. It becomes difficult to adhere.

  Using the photoresist layer 52 remaining on the substrate 10 as a mask, the portion of the second organic compound layer 32 where the photoresist layer 52 does not remain is dry-etched in the same manner as the first organic compound layer 31, and the surface of the first electrode 23 Is exposed (FIG. 2 (k)). Subsequently, a third organic compound layer 33 is formed on the substrate 10 on which the photoresist layer 52 remains on the entire region or a predetermined region including the light emitting region 12 using a vapor deposition mask or the like (FIG. 2 (l)). . Thereafter, the photoresist layer 51 is brought into contact with a stripping solution, and the third organic compound layer 33 formed on the photoresist layer 52 is stripped (FIG. 2 (m)).

  When the third organic compound layer 33 is formed without using a vapor deposition mask or the like, the photoresist layer 52 formed when patterning the second organic compound layer 32 is applied to the external connection terminal 15 and the contact portion 11 in advance. It is good to form. Then, when the third organic compound layer 33 is peeled off, the surfaces of the external connection terminals 15 and the contact portions 11 can be exposed at the same time.

  Finally, when the second electrode layer 70 and a sealing layer (not shown) are formed on the first to third organic compound layers, the first organic compound layer 31 is formed in the first light emitting portion, and the second organic compound is formed in the second light emitting portion. An organic light emitting device in which the layer 32 and the third organic compound layer 33 are formed in the third light emitting part is completed (FIG. 2 (n)).

[When a photoresist layer cannot be formed directly on the organic compound layer]
Next, when a photoresist layer cannot be formed directly on the organic compound layer, that is, each organic compound layer is dissolved in a solvent of the photoresist material, a developer solution or a stripping solution of the photoresist layer, etc. A manufacturing method in this case will be described. FIG. 3 shows a method for producing an organic light emitting layer when a photoresist layer cannot be formed directly on the organic compound layer. The same points as when the photoresist layer can be formed directly on the organic compound layer will be omitted, and only different points will be described.

  FIG. 3B shows a step of forming a protective layer 41 for protecting the first organic compound layer before the photoresist layer 51. By providing the protective layer 41, the photoresist layer 51 can be formed without dissolving the first organic compound layer 31.

  The protective layer 41 includes at least a release layer. The peeling layer here refers to a layer having high solubility in a solution in which the organic compound layer hardly dissolves. The solubility of the organic compound layer in the peeling solution of the peeling layer is 1/10 or less, more preferably 1/50 or less of the solubility of the peeling layer. As the release layer satisfying such conditions, a water-soluble material such as a water-soluble polymer material or a water-soluble inorganic salt can be suitably used. Therefore, the second organic compound layer 32 formed on the photoresist layer and the photoresist layer can be removed by the release layer without dissolving the first organic compound layer 31 and the second organic compound layer 32. Examples of the water-soluble polymer material include polyvinyl alcohol (PVA), polyacrylic acid polymer, polyethylene glycol (PEG), polyethylene oxide (PEO), and polyvinylpyrrolidone (PVP).

  If the release layer does not allow the solvent of the photoresist material or the photoresist layer developer to permeate the organic compound layer and does not dissolve in these solutions, only the release layer is formed as a protective layer on the organic compound layer. do it. However, when the release layer permeates the solvent of the photoresist material, the developer of the photoresist layer or the like, or dissolves in these solutions, the release layer serves as the first protective layer, and the release layer and the photoresist layer 51 A second protective layer is further formed between the two. By providing the second protective layer, the photoresist layer 51 can be formed without dissolving the first organic compound layer 31. As the second protective layer, a highly moisture-proof inorganic film such as silicon nitride, silicon oxide, aluminum oxide, or the like is suitable. The protective layer 41 may be formed by, for example, applying a coating layer such as a spin coating method or a dip coating method for a release layer (first protective layer) made of a water-soluble polymer, and a coating method for a layer made of a water-soluble inorganic salt. It can select suitably from well-known methods by the material of the layer to form, such as a vacuum evaporation method. Similarly, in the case of forming the second protective layer, a vacuum film forming method such as a vacuum deposition method, a sputtering method, or a CVD method can be selected and used in addition to the coating method. After the protective layer 41 is formed, a photoresist layer 51 is formed in the same manner as when the protective layer 41 is not formed (FIGS. 3C to 3E).

Next, the first organic compound layer 31 is patterned by dry etching using the photoresist layer 51 as a mask (FIG. 3F). When dry etching the first organic compound layer 31, it is necessary to remove the protective layer 41 in a region where the photoresist layer does not remain. Depending on the material of the protective layer 41 and the first organic compound layer 31, a suitable dry etching method or etching gas may be used. For example, the second protective film formed of an inorganic material is etched using a chemically reactive gas such as CF ₄ , and the release layer (first protective layer) formed using a water-soluble polymer is etched using oxygen gas. Is preferred. FIG. 3F shows a state in which the photoresist layer 51 is removed while the first organic compound layer 31 is dry-etched. Even if the photoresist layer 51 is removed as shown in FIG. 3F, there is no particular problem as long as the protective layer 41 remains when the patterning of the first organic compound layer 31 is completed. After the photoresist layer 51 disappears, the protective layer 41 serves as an etching mask. Of course, the photoresist layer 51 may remain when the patterning of the first organic compound layer 31 is completed.

  A second organic compound layer 32 is formed on the entire surface of the substrate 10 where the protective layer 41 remains on the surface of the patterned first organic compound layer 31 (FIG. 3G). Thereafter, when the substrate 10 on which the second organic compound layer 32 is formed is immersed in a peeling solution of the peeling layer (first protective layer), the peeling layer dissolves and the second organic compound layer 32 formed on the peeling layer. Is peeled off. Even when the second protective layer is formed, the second organic compound layer can be peeled off by dissolving the peeling layer. When the release layer is formed of a water-soluble polymer, as the release solution, pure water or a mixed solution obtained by mixing 10 to 50% of an organic solvent such as isopropyl alcohol with pure water can be used. By mixing an appropriate amount of an organic solvent with pure water, the solubility of the release layer can be increased while keeping the solubility of the second organic compound layer 32 at a low value. For the same reason, it is also preferable to heat and use the stripping solution.

  If the edge part of a peeling layer is covered with the 2nd organic compound layer 32, it will become difficult for a peeling liquid to osmose | permeate. Therefore, it is preferable to use the following first to third methods alone or in combination as necessary. In the first method, the organic compound layers are formed in order of increasing film thickness. A 2nd method makes the film thickness of a peeling layer thicker than the total film thickness of a 1st organic compound layer and a 2nd organic compound layer. The third technique is to form a film thickness of the layer remaining on the surface of the first organic compound layer 31 after the patterning of the first organic compound layer 31 to be 100 times or more of the film thickness of the second organic compound layer 32. 2 The organic compound layer 32 is less likely to be formed at the end. By using these methods, the peeling solution penetrates from the end of the peeling layer, and the peeling can be performed efficiently.

  After removing the second organic compound layer 32 formed on the protective layer 41 together with the protective layer 41, a new photoresist layer 52 is formed in a predetermined pattern, and the second organic compound is formed using the photoresist layer 52 as a mask. The layer 32 is patterned by dry etching (FIGS. 3 (i) to (m)). After the dry etching, a third organic compound layer 33 is formed on the substrate 10 where at least the protective layer 42 remains on the first electrodes 21 and 22 (FIG. 3 (n)), and the photoresist layer 52 together with the protective layer 42 is formed. The upper third organic compound layer 33 is peeled off (FIG. 3 (o)). These steps can be performed in the same manner as the steps already described.

  In the case where a water-soluble material is used for the release layer, it is not suitable to use a water-soluble material for the material formed before the light emitting layer. However, there is no problem even if the water-soluble material is formed after the first to third light emitting layers are patterned. For example, a material containing an alkali metal or alkaline earth metal with a high electron-injecting property is a preferable material for the electron-injecting layer. However, it reacts with moisture or oxygen and loses the electron-injecting property. It is difficult to pass through the process of touching a mixture of water and an organic solvent without problems. Therefore, when a material containing an alkali metal or an alkaline earth metal is used as the electron injection layer, after the patterning step (FIG. 3 (o)) of the third organic compound layer 33 is completed, the first to third light emitting portions are formed. What is necessary is just to form as a common electron injection layer. After the electron injection layer is formed, the second electrode 70 is formed (FIG. 3 (p)), and a sealing layer is provided.

  As described above, when the release layer is continuously formed on the plurality of light emitting portions, a film piece such as the second organic compound layer to be peeled is obtained by selectively dissolving the release layer by contacting with the release liquid. Can be bigger. Therefore, compared with the case where the organic compound layer is patterned for each first electrode, the number of film pieces to be peeled can be reduced, and the peeled film pieces can be prevented from adhering to the substrate. As a result, it is possible to suppress leakage, short circuit, non-light emission, and the like caused by the peeled film piece adhering to the patterned substrate, and to obtain an organic light emitting device with good performance.

  By the way, when the release liquid is brought into contact with the release layer and dissolved, the release liquid gradually enters from the end of the release layer. Therefore, it takes a long time to cause the release liquid to enter the release layer having a relatively large area as in the present invention to dissolve the entire release layer, resulting in a decrease in productivity. is there. Therefore, in the present invention, in order to further improve the productivity, when forming a photoresist layer for patterning each organic compound layer, a slit for allowing the stripping solution to enter the non-light emitting region (non-light emitting portion). It is good to provide. FIG. 6 shows an example of a pattern that can improve the pattern of FIG. 4 and reduce the time required for peeling. 6A shows a pattern of the photoresist layer when the first organic compound layer 31 is patterned, and FIG. 6B shows a pattern of the photoresist layer when the second organic compound layer 32 is patterned. In any of the photoresist layer patterns, a slit 80 is formed so as to avoid the top of the first electrode serving as the light emitting portion and to allow the stripping solution to enter the non-light emitting portion. In FIG. 6, the light emitting portion is provided so as to avoid the first electrode, but the position where the slit 80 is provided is not particularly limited as long as it is a non-light emitting portion. For example, when the first electrode is divided into a plurality of portions by the partition layer, it may be provided on the partition layer. The slit 80 may be designed as appropriate according to the area and arrangement of the light emitting portion, but it is preferable to design the pattern of the photoresist layer so that it is not broken during the process. By providing the slits 80 in this way, even if the release layer is formed in a large pattern continuous to a plurality of light emitting portions, the release solution can be penetrated into the release layer in a short time because the intrusion route of the release solution is increased. , Productivity can be improved. The slit is not limited to the example of FIG. 6 and may be provided in any manner as long as it is provided in the non-light emitting portion and the release layer is continuously formed in the plurality of light emitting portions.

  Furthermore, the patterning in the present invention is not limited to the stripe arrangement as shown in FIGS. 4 and 5, but can also be applied to the delta arrangement. In this case as well, slits may be similarly provided if necessary. it can.

  Examples according to the present invention will be specifically described below.

[Example 1]
An example of manufacturing an organic light emitting device by the manufacturing method shown in FIG. 2 will be described. In this example, each organic compound layer was formed in the pattern shown in FIG.

  A glass substrate provided with a circuit layer made of a transistor and an insulating layer covering the circuit layer was prepared as the substrate 10. After sequentially depositing Ag and IZO on one whole surface of the substrate 10 by a sputtering method, patterning for dividing each light emitting portion was performed to form a plurality of first electrodes 21 to 23 in the row direction and the column direction.

  After the surface of each first electrode is cleaned by performing UV ozone treatment, poly (3,4) ethylenedioxythiophene / polystyrene sulfonate (PEDT / PSS: Baytron P manufactured by Bayer) is applied to the first electrode by spin coating. After being applied to the entire substrate surface on which was formed, it was dried to prepare a hole injection layer having a thickness of 1000 mm. Subsequently, a 2 wt% toluene solution containing polyvinyl carbazole as a main component was applied to the entire surface of the hole injection layer by spin coating and then dried to form a first light emitting layer having a thickness of 800 mm. As described above, in this example, the first organic compound layer 31 composed of the hole injection layer and the first light emitting layer was formed (FIG. 2A).

  A positive photoresist material (manufactured by Tokyo Ohka Kogyo Co., Ltd .: OFPR-800) is dropped onto the first organic compound layer 31 to form a film thickness of 1 μm by spin coating, and the film is formed at 80 ° C. for 30 minutes. Pre-baking was performed (FIG. 2 (b)). The substrate 10 on which the photoresist layer 51 was formed was set in an exposure apparatus, and exposure was performed so that the photoresist layer remained on the plurality of first electrodes 21 provided with the first light emitting portion (FIG. 2C). . At the time of exposure, a photomask 61 on which the same light shielding pattern as the photoresist layer 51 shown in FIG. 4B was formed was used. The light shielding pattern is continuous across the plurality of first electrodes 21 for one row.

  Subsequently, the substrate 10 after exposure was immersed in a developer (Tokyo Ohka: NMD-3) for development, washed with running water, and baked. The substrate 10 from which the portion of the photoresist layer not exposed by development was removed was put into a dry etching apparatus, and the first organic compound layer was removed by etching with oxygen plasma using the remaining photoresist layer as a mask. (FIG. 2 (e)).

  Similar to the first organic compound layer 31, the second organic compound layer 32 including the hole injection layer and the second light emitting layer is formed on the entire surface of the substrate 10 where the first organic compound layer 31 and the photoresist layer 51 remain. (FIG. 2 (f)). In the hole injection layer, 600 Å of the same material as the first organic compound layer was formed. For the second light emitting layer, a 1 wt% xylene solution containing polyparaphenylene vinylene derivative polymer material (MEH-PPV) as a main component is applied onto the whole surface of the hole injection layer by spin coating, and the solvent is dried to form a film thickness. It formed so that it might become 500 mm (FIG. 2 ()). Together with the second organic compound layer 32 formed on the photoresist layer 51 by immersing the substrate 10 on which the second organic compound layer 32 is formed in acetone and applying ultrasonic waves to dissolve the photoresist layer 51. It was made to peel (FIG.2 (g)).

  Subsequently, a new photoresist layer was formed in the same manner as described above on the substrate 10 on which the first organic compound layer 31 and the second organic compound layer were formed (FIG. 2H). At the time of exposure, a photomask 62 having the same light shielding pattern as the photoresist layer 52 shown in FIG. 4C was used (FIG. 2I). The light shielding pattern is continuous across the row of the first electrodes 21 and the row of the first electrodes 22 adjacent to each other. The exposed substrate 10 was developed by immersing it in a developer (Tokyo Ohka: NMD-3), washed with running water, and then poured into a dry etching apparatus to remove the photoresist layer 52. A portion of the second organic compound layer was removed by etching with oxygen plasma (FIG. 2 (j)).

  Similarly to the first and second organic compound layers, a hole injection layer 400 Å and a third light emitting layer were formed as the third organic compound layer 33 on the substrate 10 where the photoresist layer remains (FIG. 2L). ). The third light-emitting layer was formed so that a 1 wt% xylene solution containing polyparaphenylene vinylene derivative polymer material (MEH-PPV) as a main component was applied over the entire surface by spin coating and dried to a film thickness of 400 mm. .

  Next, the photoresist layer 52 was dissolved in the same manner as the photoresist layer 51, and removed together with the third organic compound layer 33 formed on the photoresist layer 52 (FIG. 2 (m)). The surface of the first organic compound layer 31, the second organic compound layer 32, and the third organic compound layer 33 formed in the pattern of FIG. The substrate 10 on which the patterning of each light emitting layer has been completed is heated at 100 ° C. for 30 minutes to sufficiently dissipate heat, and then Ag and Mg are co-evaporated, and the second electrode 70 having a ratio of Ag: Mg of about 8: 2. Was deposited to a thickness of 20 nm (FIG. 2 (n)). Finally, the substrate 10 on which the second electrode 70 was formed was transferred to a glove box connected to a vacuum deposition apparatus, and sealed with cap glass containing a desiccant in a nitrogen atmosphere.

  When a plurality of organic light emitting devices manufactured by the above method were energized and the light emission of each light emitting part was confirmed, none of the light emitting parts was noticeable, and good light emission could be obtained in all the light emitting parts.

[Example 2]
In this example, each organic compound layer was formed by vacuum deposition, a functional layer other than the electron injection layer was formed, and a protective layer was provided between each organic compound layer and the photoresist layer, This example is different from Example 1 in that silicon nitride is formed as a sealing layer. The manufacturing process of this embodiment is the same as that shown in FIG. In this example, each organic compound layer was formed in the pattern shown in FIG.

  As in Example 1, a glass substrate on which a circuit layer was formed was used as the base 10 to form a plurality of first electrodes 21 to 23. Thereafter, the surface of each first electrode was cleaned in the same manner as in Example 1, and then a laminated film composed of a hole transport layer, a first light emitting layer, and an electron transport layer was formed as the first organic compound layer (see FIG. 3 (a)). The hole transport layer is 2000 α α-NPD, the first light emitting layer (red light emitting layer) is CBP doped with Ir (piq) 3, and the hole blocking layer is 100 ク リ chrysene-based material. Films were formed in order by vacuum deposition.

  Subsequently, polyvinyl pyrrolidone (PVP) as a release layer (first protective layer) was dissolved to 5 wt% with respect to pure water, and the entire surface on which the first organic compound layer was formed was applied by spin coating, It was heated at 100 ° C. for 10 minutes to form a film thickness of 0.5 μm. After the release layer was formed, the substrate 10 was put into a CVD film forming apparatus, and a silicon nitride film having a thickness of 3 μm was formed as a second protective layer to form a protective layer 41 (FIG. 3B).

  A photoresist layer patterned by the same method as in Example 1 was formed on the silicon nitride film (FIGS. 3C to 3E). The substrate 10 having the photoresist layer remaining at the position of the first light emitting portion was put into a dry etching apparatus, and the silicon nitride film as the second protective layer was removed by etching with CF4 plasma. Subsequently, PVP and the first organic compound layer were continuously removed using oxygen plasma (FIG. 3F). At this time, the surface of the photoresist was also etched by oxygen plasma, and when the removal of PVP and the first organic compound layer was completed, the photoresist layer disappeared and the surface of the second protective layer was exposed.

  The substrate 10 having the protective layer remaining at the position of the first light emitting portion was put into a vacuum film forming apparatus, and the second organic compound layer 32 was formed by a vacuum deposition method (FIG. 3G). The second organic compound layer 32 has a hole injection layer made of molybdenum oxide of 10Å, a hole transport layer made of α-NPD of 1600Å, a second light emitting layer (green light emitting layer) doped with coumarin 6 in Alq3 of 300Å, A hole blocking layer made of a chrysene-based material was formed by sequentially laminating 100 mm.

  The base 10 on which the second organic compound layer 32 is formed is immersed in pure water, ultrasonic vibration is applied, PVP is dissolved, a silicon nitride film, and a second organic compound layer formed on the silicon nitride film Was peeled off together with PVP (FIG. 3 (h)). Subsequently, after the PVP and silicon nitride films are formed on the first organic compound layer 31 and the second organic compound layer 32 by the same method as before, the PVP, silicon nitride film and the first electrode on the first electrode 23 are formed. Two organic compound layers were removed (FIGS. 3 (i) to (m)).

  A third organic compound layer 33 was formed on the substrate 10 on which the protective layer remained on the first electrodes 21 and 22 by a vacuum film forming apparatus (FIG. 3 (n)). The third organic compound layer has a hole injection layer made of molybdenum oxide of 10 な る, a hole transport layer made of α-NPD of 1000Å, and a third light emitting layer (blue light emitting layer) made of anthracene derivative doped with perylene. A hole blocking layer made of chrysene-based material was formed by sequentially laminating 300 mm and 100 mm.

  In the same manner as before, the substrate 10 is immersed in pure water, ultrasonic vibration is applied, PVP is dissolved, and the silicon nitride film and the third organic compound layer formed on the silicon nitride film are combined with PVP. It was made to peel (FIG.3 (o)). The surface of the first organic compound layer 31, the second organic compound layer 32, and the third organic compound layer 33 formed in the pattern of FIG.

  The substrate 10 is put in a vacuum atmosphere, heated at 100 ° C. for 30 minutes and sufficiently dissipated, and then an electron transport layer and an electron injection layer common to the first to third light emitting portions are formed by a vacuum film formation method. (Not shown). 100 electron bathophenanthroline was formed as the electron transport layer, and 60 nm was formed as the electron injection layer by co-evaporation of bathophenanthroline and cesium carbonate (Cs2CO3) at a volume ratio of 7: 3. Then, 12 nm of the 2nd electrode 70 which consists of Ag was formed using sputtering method (FIG.3 (p)). Finally, a silicon nitride film having a thickness of 6 μm was formed as a sealing film on the entire surface of the substrate 10 on which the light emitting portion was formed by the CVD method.

  When the plurality of organic light emitting devices obtained by the above method were energized and the light emission of each light emitting part was confirmed, none of the light emitting parts was noticeable, and good light emission could be obtained in all the light emitting parts. .

[Example 3]
This example is different from Example 1 except that each organic compound layer is formed in the pattern shown in FIG. Since each manufacturing process is the same as that of Example 1, description is abbreviate | omitted here.

  In this embodiment, as shown in FIG. 6, slits are provided in the non-light-emitting portion to increase the intrusion route of the stripping solution. Therefore, when the second organic compound layer 32 and the third organic compound layer 33 are stripped by dissolving the stripping layer. It was possible to peel in a shorter time than the time taken for peeling in Example 1. When the obtained plurality of organic light emitting devices were energized and the light emission of each light emitting part was confirmed, none of the light emitting parts was noticeable, and good light emission could be obtained in all the light emitting parts.

DESCRIPTION OF SYMBOLS 10 Base | substrate 11 Contact part 12 Light emission area | region 15 External connection terminal 21-23 1st electrode 31 1st organic compound layer 32 2nd organic compound layer 33 3rd organic compound layer 41 Protective layer 51-52 Photoresist layer 70 2nd electrode

Claims (2)

Forming a first organic compound layer including at least a first light emitting layer on a substrate on which a plurality of first electrodes are formed according to a plurality of light emitting portions;
Selectively forming a release layer continuous over a portion of the plurality of light emitting portions on the first organic compound layer;
Removing the portion of the first organic compound layer where the release layer is not formed;
Forming a second organic compound layer including at least a second light emitting layer on the portion from which the first organic compound layer has been removed and the release layer;
The base on which the second organic compound layer is formed is brought into contact with a release liquid that selectively dissolves the release layer, and both the release layer and the second organic compound layer formed on the release layer are brought together. And a step of removing the organic light-emitting device.   In the step of selectively forming a release layer continuous over a part of the plurality of light emitting portions on the first organic compound layer, a slit is provided in the release layer formed in the non-light emitting portion. The manufacturing method of the organic light-emitting device of Claim 1.

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