JP2014135250A - Organic light emitting device and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic light emitting device causing no crack and separation in an organic compound layer that is formed on an element isolation film using a photolithography method.SOLUTION: An organic light emitting device 1 includes an organic light emitting element and an element isolation film 11 provided on the periphery of the organic light emitting element. The organic light emitting element has a first electrode provided on a substrate 10, an organic compound layer and a second electrode 23. The organic compound layer covers at least a part of a surface of the element isolation film 11, and is formed to have a predetermined shape by a photolithography method. An interposing layer 12 is provided between the element isolation film 11 and the organic compound layer, in at least a part of a region where the organic compound layer covers the element isolation film 11. The interposing layer 12 includes one of an organic compound having a hydrophobic site at a terminal of a molecule, an oxide thereof, an organic compound having a hydrophobic substituent, and an oxide thereof.

Description

  The present invention relates to an organic light emitting device and a manufacturing method thereof.

  An organic light emitting device is a device in which a plurality of organic light emitting elements are arranged in a matrix on a substrate. Here, a combination of organic light-emitting elements that output red, green, or blue colors is arranged as a single pixel, for example, in a matrix, thereby displaying a full color.

  By the way, the organic light emitting element which comprises an organic light-emitting device has arrange | positioned the organic compound layer with a film thickness of several dozen nm thru | or several hundred nm between a pair of electrodes including the light emitting layer which contributes to light emission. Here, by appropriately selecting a light emitting material to be included in the light emitting layer, the light emitting color of the organic light emitting element can be changed to various colors.

  As a method for forming an organic compound layer that is a constituent member of an organic light emitting element included in an organic light emitting device, a vacuum deposition method is widely used. A metal having an opening in a region corresponding to a region where a light emitting material is formed in order to selectively form a light emitting material in accordance with an organic light emitting element by vacuum deposition when manufacturing a multicolor display organic light emitting device. A predetermined light emitting material is selectively formed in a predetermined region using a mask. However, the vacuum deposition method using a metal mask has problems that the alignment accuracy between the metal mask and the deposition target substrate is low and the film formation accuracy is low due to thermal expansion of the metal mask. For this reason, it is not suitable for manufacturing a high-definition light-emitting device.

  Here, Patent Document 1 discloses a method of selectively forming an organic compound layer with high accuracy using a photolithography method without using a high-definition metal mask. Specifically, an intermediate layer composed of a water-soluble polymer and a resist layer are sequentially provided on the organic compound layer formed on the entire substrate, and the resist layer and the intermediate layer are patterned in a desired shape by a known method. I do. Then, the organic compound layer is patterned using the resist layer and the intermediate layer as a mask. Then, after patterning the organic compound layer, the intermediate layer is dissolved with water, and the intermediate layer and the resist layer are removed (lifted off) from above the organic compound layer. Through the series of steps described above, an organic compound layer having a desired pattern shape can be obtained.

Japanese Patent No. 4507759

  By the way, in the method disclosed in Patent Document 1, the intermediate layer and the photoresist layer are formed from the organic compound layer side for the purpose of reducing damage to the organic compound layer when the resist layer is applied, exposed, developed, and the like. Is used as a mask. In Patent Document 1, a water-soluble material is used as a constituent material of the intermediate layer. Thereby, since the photoresist layer can be removed by dissolving the intermediate layer in water or alcohol, the organic compound layer is not damaged. In addition to the intermediate layer of Patent Document 1, a sacrificial layer soluble in a polar solvent is formed in advance between the intermediate layer and the organic compound layer in order to suppress residues of the constituent materials of the intermediate layer and the resist layer. May be.

  However, when such a sacrificial layer is employed, when the sacrificial layer is removed, the organic compound layer under the sacrificial layer is cracked or peeled off, and fragments of the organic compound layer generated due to cracking / peeling. In some cases, the quality of the organic light-emitting device is impaired, for example, scattering in the display region and causing a light emission failure. In particular, when the element separation film is made of an inorganic compound, the organic compound layer is easily cracked or peeled off on the element separation film provided to separate adjacent electrodes on the substrate and partition the light emitting region. It becomes more prominent. This is because the adhesion between the device isolation film having a hydrophilic surface and the organic compound layer having a relatively hydrophobic surface is insufficient, and cracking or peeling occurs due to the polar solvent entering the interface. Conceivable.

  Further, the above-described cracking or peeling may occur due to temperature stress such as thermal shock. The above-described cracking and peeling have also been a cause of impairing the reliability of the organic light emitting device.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an organic light-emitting device in which the organic compound layer formed on the element isolation film is not cracked or peeled off using a photolithography method. There is.

An organic light emitting device of the present invention includes an organic light emitting element provided on a substrate,
An element isolation film provided on the substrate and around the organic light emitting element,
The organic light emitting device has a first electrode provided on the substrate, an organic compound layer provided on the first electrode, and a second electrode provided on the organic compound layer,
The organic compound layer covers at least a part of the surface of the element isolation film;
The organic compound layer is formed in a predetermined shape by a photolithography method,
In at least part of the region where the organic compound layer covers the element isolation film, an intervening layer is provided between the element isolation film and the organic compound layer,
The intervening layer has any one of an organic compound having a hydrophobic site at its molecular end and an oxide thereof, and an organic compound having a hydrophobic substituent and an oxide thereof.

  ADVANTAGE OF THE INVENTION According to this invention, the organic light-emitting device which a crack and peeling do not arise in the organic compound layer formed on the element separation film using the photolithographic method can be provided.

  That is, in the organic light emitting device of the present invention, an intervening layer made of a predetermined organic compound and improving the adhesion between the element isolation film and the organic compound layer is provided between the element isolation film and the organic compound layer. For this reason, even if it exposes to the solvent used when removing the sacrificial layer used by the photolithographic method, a crack of an organic compound layer and peeling from an element isolation film can be suppressed. Further, by providing the intervening layer, the organic compound layer on the element isolation film is not peeled off from the element isolation film due to temperature stress. Therefore, the organic light emitting device of the present invention is a highly reliable organic light emitting device.

It is a cross-sectional schematic diagram which shows the example of embodiment in the organic light-emitting device of this invention. It is a cross-sectional schematic diagram which shows the example of the manufacturing process of the organic light-emitting device which has two types of subpixels. It is a cross-sectional schematic diagram which shows the example of the manufacturing process of the organic light-emitting device which has three types of subpixels.

  The organic light emitting device of the present invention includes an organic light emitting element provided on a substrate and an element isolation film provided on the substrate and around the organic light emitting element. In the present invention, the organic light emitting device has a first electrode provided on the substrate, an organic compound layer provided on the first electrode, and a second electrode provided on the organic compound layer. doing.

  In the present invention, the organic compound layer is a layer that covers at least a part of the surface of the element isolation film and is formed in a predetermined shape by a photolithography method.

  Here, in the present invention, an intervening layer is provided between the element isolation film and the organic compound layer in at least a part of the region where the organic compound layer covers the element isolation film. In the present invention, the intervening layer includes any one of an organic compound having a hydrophobic site at the end of the molecule and its oxide, and an organic compound having a hydrophobic substituent and its oxide.

  Embodiments of the present invention will be specifically described below with reference to the drawings. It should be noted that well-known or well-known techniques in the technical field can be applied to matters that are not particularly illustrated in the drawings or that are not particularly described in the following description. The embodiments described below are merely examples, and the present invention is not limited to these embodiments.

[Organic light-emitting device]
FIG. 1 is a schematic cross-sectional view showing an example of an embodiment of the organic light-emitting device of the present invention, where (a) shows the first embodiment and (b) shows the second embodiment. .

  In the organic light emitting device 1 of FIG. 1A, two types of organic light emitting elements having different emission colors, that is, a first organic light emitting element 20a and a second organic light emitting element 20b are provided on a substrate 10, respectively. Yes.

  In the organic light emitting device 1 of FIG. 1A, the first organic light emitting element 20a includes a first electrode 21a provided on the substrate 10, a first organic compound layer 22a, and a second electrode 23 sequentially stacked. It is a member made. In the organic light emitting device 1 of FIG. 1A, the second organic light emitting element 20b includes a first electrode 21b, a second organic compound layer 22b, and a second electrode 23 provided on the substrate 10 sequentially. It is a member formed by lamination.

  In the organic light emitting device 1 of FIG. 1A, the first electrodes (21 a and 21 b) are separated by an element isolation film 11. That is, the two types of organic light emitting devices (20a, 20b) are partitioned by the device isolation film 11, respectively. Here, an intervening layer 12 is provided on the element isolation film 11 constituting the organic light emitting device 1 of FIG. Further, in the organic light emitting device 1 of FIG. 1A, the end portion of the first organic compound layer 22 a or the second organic compound layer 22 b covers the intervening layer 12. That is, in the organic light emitting device 1 in FIG. 1A, the end portion of the first organic compound layer 22 a or the second organic compound layer 22 b covers the element isolation film 11. In the present invention, each organic compound layer (22a, 22b) only needs to cover a part of the element isolation film 11, but as shown in FIG. 1 (a), each organic compound layer (22a) 22b), the surface of the element isolation film 11 is preferably covered.

  The organic light emitting device 2 shown in FIG. 1B has three kinds of organic light emitting elements having different emission colors on the substrate 10, that is, a first organic light emitting element 20a, a second organic light emitting element 20b, and a third organic light emitting element. 20c are provided.

  In the organic light emitting device 2 of FIG. 1B, the first organic light emitting element 20a is the same as the first organic light emitting element 20a in FIG. Further, in the organic light emitting device 2 of FIG. 1B, the second organic light emitting element 20b is the same as the second organic light emitting element 20b in FIG. In the organic light emitting device 2 of FIG. 1B, the third organic light emitting element 20c includes a first electrode 21c provided on the substrate 10, a third organic compound layer 22c, and a second electrode 23 sequentially stacked. It is a member made.

  In the organic light emitting device 2 of FIG. 1B, the first electrodes (21 a, 21 b, 21 c) are separated by the element isolation film 11. That is, the three types of organic light emitting elements (20a, 20b, 20c) are each partitioned by the element isolation film 11. Here, an intervening layer 12 is provided on the element isolation film 11 constituting the organic light emitting device 1 of FIG. 1B as in the case of FIG. Further, in the organic light emitting device 1 in FIG. 1B, any end portion of each organic compound layer (22 a, 22 b, 22 c) covers the intervening layer 12. That is, in the organic light emitting device 2 in FIG. 1B, any one end portion of each organic compound layer (22 a, 22 b, 22 c) covers the element isolation film 11. As in FIG. 1A, in FIG. 1B, it is preferable that the surface of the element isolation film 11 is covered with any one of the organic compound layers (22a, 22b, 22c).

In the present invention, the intervening layer 12 is a layer having any of the compounds shown in the following (i) to (iv).
(I) A compound obtained by oxidizing an organic compound (ii) (i) having a hydrophobic site at the end of the molecule (oxide of (i))
(Iii) An organic compound having a hydrophobic substituent (iv) (iii) obtained by oxidizing a compound (oxide of (iii))

  Details of the compounds represented by (i) to (iv) will be described later.

[Method for Manufacturing Organic Light-Emitting Device]
Next, the manufacturing method of the organic light emitting device of the present invention will be described.

  FIG. 2 is a schematic cross-sectional view illustrating an example of a manufacturing process of an organic light emitting device having two types of subpixels. The manufacturing process shown in FIG. 2 is also a manufacturing process of the organic light emitting device 1 of FIG. Hereinafter, the manufacturing method of the organic light-emitting device of the present invention will be described based on the manufacturing process of FIG.

(1) Substrate The substrate 10 on which the organic light emitting element is provided is provided with a display area (not shown) and an external connection terminal (not shown). Here, the first organic light emitting element 20a including the first organic compound layer 22a and the second organic light emitting element 20b including the second organic compound layer 22b are two-dimensionally arranged in the display area. On the other hand, the external connection terminal is electrically connected to a circuit (not shown) built in the substrate 10 by wiring (not shown).

  By the way, in FIG. 2, for simplification of the drawing, only one pixel composed of a combination of one first organic light emitting element 20a and one second organic light emitting element 20b is displayed. In practice, however, a plurality of pixels composed of the first organic light emitting element 20a and the second organic light emitting element 20b are two-dimensionally arranged.

(2) First electrode formation process (FIG. 2A)
First, the first electrode (21a, 22b), the element isolation film 11 and the intervening layer 12 are sequentially formed in predetermined regions on the substrate 10 (FIG. 2A).

  The substrate 10 (element substrate) is not particularly limited as long as the organic light-emitting device can be stably manufactured and the manufactured organic light-emitting device can be driven. For example, an insulating or semiconductor support substrate such as glass or silicon wafer, a drive circuit for driving the organic light emitting device, and a planarization layer for planarizing unevenness caused by the drive circuit are sequentially laminated. A circuit board with the following structure can be used.

  As a specific constituent material of the first electrode (21a, 22b), for example, a metal material such as aluminum or silver, or a transparent electrode material such as indium tin oxide (ITO) or indium zinc oxide can be used. . The first electrode (21a, 21b) can be formed as a single layer made of the metal material or the transparent electrode material, but the metal material and the transparent electrode material are laminated. It may be formed as a laminated electrode film.

  As a method for forming the first electrodes (21a, 22b), a conventionally known method such as a vacuum deposition method, a sputtering method, a CVD method, or the like can be used. Specifically, after a conductive layer is formed over the entire surface of the substrate 10 by vacuum deposition or the like, this conductive layer is patterned for each element using a photolithography method to form each organic light emitting element (20a, 20b). The corresponding first electrodes (21a, 21b) are respectively formed. In addition, the 1st electrode (21a, 21b) formed at this process may be one, respectively, and two or more may be sufficient as it.

  The constituent material of the element isolation film 11 is preferably an insulating material such as silicon oxide, silicon nitride, or silicon oxynitride if it is an inorganic material, and acrylic resin, polyimide resin, novolac resin, or the like if it is an organic material. desirable. In the present invention, the organic compound layer is patterned by photolithography as described later. At this time, since dry etching or wet etching is used, the constituent material of the element isolation film 11 is preferably a material having etching resistance. Therefore, in the present invention, the constituent material of the element isolation film 11 is preferably an inorganic material.

  Examples of the method for forming the element isolation film 11 include a method of forming a film made of a predetermined material over the entire surface of the substrate 10 and then patterning (processing) the film by a photolithography method. In the case where an inorganic material is used as the constituent material of the element isolation film 11, examples of a film forming method for forming the element isolation film 11 include conventionally used methods such as vacuum deposition, sputtering, and CVD. It is done. On the other hand, when an organic material is used as the constituent material of the element isolation film 11, examples of the film formation method for the element isolation film 11 include a spin coat method and a slit coat method.

The intervening layer 12 formed next to the element isolation film 11 is a layer having any one of the compounds shown in the following (i) to (iv).
(I) A compound obtained by oxidizing an organic compound (ii) (i) having a hydrophobic site at the end of the molecule (oxide of (i))
(Iii) An organic compound having a hydrophobic substituent (iv) (iii) obtained by oxidizing a compound (oxide of (iii))

  In the present invention, the intervening layer 12 only needs to be provided in a region where the organic compound layer (22a, 22b) formed in at least a later step covers the element isolation film 11. Preferably, as shown in FIG. 2A, an intervening layer 12 is provided so as to cover the surface of the element isolation film 11. In the present invention, the intervening layer 12 may be formed on a portion other than the surface of the element isolation film 11 as long as the light emitting performance of the organic light emitting elements (20a, 20b) is not impaired.

  Examples of the material shown in (i) above include organic compounds having a hydrophobic molecular end such as diamond-like carbon (hydrogenated amorphous carbon).

  The material shown in the above (ii) is a compound in which a part of the material shown in the above (i) is oxidized by an oxidizing agent or the like. However, the material shown in the above (ii) is a hydrophobic compound like the material shown in the above (i).

  As the material shown in (iii) above, for example, a compound having a hydrophobic group represented by an alkyl group or a phenyl group, more specifically, an acrylic resin, a polyimide resin, a novolac resin, an epoxy resin, etc. An organic polymer compound is mentioned.

  The material shown in (iv) is a compound in which a part of the material shown in (iii) is oxidized by an oxidizing agent or the like. However, the material shown in the above (iv) is a hydrophobic compound like the material shown in the above (iii).

  Examples of a method for forming the film that becomes the intervening layer 12 include a vacuum deposition method, a sputtering method, a CVD method, a spin coating method, a slit coating method, and the like, which are appropriately selected according to the material to be used. However, if a film that becomes the intervening layer 12 is formed on the first electrode (21a, 21b), the light emission characteristics of the organic light emitting element (20a, 20b) may be impaired. In such a case, it is desirable to process the film that becomes the intervening layer 12 using a photolithographic method and to partially remove the intervening layer 12 on the first electrodes (21a, 21b).

  In addition, the intervening layer 12 may be formed (patterned) together with the element isolation film 11 by a photolithography method after being formed over the entire surface of the substrate 10 before the element isolation film 11 is patterned.

  Further, as the constituent material of the intervening layer 12, a resist material used in patterning the element isolation film 11 using a photolithography method can be employed. In such a case, after the element isolation film 11 is processed using the resist material, a film made of the resist material on the element isolation film 11 can be used as the intervening layer 12 as it is.

  By the way, a film (a film corresponding to an intervening layer) made of a resist material on the element isolation film 11 by using an etching source such as an etching gas used when patterning the element isolation film 11 using a photolithography method. The surface may be oxidized.

(3) Step of forming the first organic compound layer (FIG. 2B)
Next, the first organic compound layer 22a is formed over the entire surface of the substrate 10 (FIG. 2B). Here, since the first electrode (21a, 21b) and the laminated body of the element isolation film 11 and the intervening layer 12 are formed on the substrate 10, the first organic compound layer 22a includes the first electrode (21a, 21b). ) Or on the intervening layer 12.

  The first organic compound layer 22a is a single layer film having at least a light emitting layer or a laminated film composed of a plurality of layers. When the first organic compound layer 22a is a laminated film composed of a plurality of layers, the layers constituting the first organic compound layer 22a and other than the light emitting layer include a hole injection layer, a hole transport layer, an electron Examples include a transport layer and an electron injection layer.

  The constituent material of the first organic compound layer 22a can be appropriately selected from known low molecular weight materials or high molecular weight materials.

(4) Sacrificial layer and release layer forming step (FIG. 2C)
Next, a sacrificial layer 31a and a release layer 32 are sequentially formed on the first organic compound layer 22a (FIG. 2C).

  The sacrificial layer 31a and the release layer 32 are formed for the purpose of protecting the first organic compound layer 22a from the solvent or developer of the resist layer 40 formed in a later step.

  As a constituent material of the sacrificial layer 31a, a material having an etching rate with respect to a polar solvent used in a later step (sacrificial layer removing step) is larger than that of the constituent material of the first organic compound layer 22a.

  The etching rate of the sacrificial layer 31a with respect to the polar solvent is preferably 10 times or more, more preferably 100 times or more the etching rate of the first organic compound layer 22a. If the etching rate of the sacrificial layer 31a with respect to the polar solvent is less than 10 times the etching rate of the first organic compound layer 22a, the sacrificial layer 31a is exposed in the subsequent step (sacrificial layer removing step). The in-plane uniformity of the first organic compound layer 22a may decrease. In addition, a part of the exposed first organic compound layer 22a is etched, and the device characteristics of the first organic light emitting device 20a may be deteriorated.

  In the present invention, as the constituent material of the first organic compound 22a, a compound having no polar site in either the main skeleton or the substituent is used. It is preferable to select a compound having a polar site in the group. The compound containing a polar site here refers to, for example, a compound containing a heterocyclic ring, specifically, a heterocyclic compound shown below.

  As described above, by appropriately selecting the constituent material of each layer (first organic compound layer 22a, sacrificial layer 31a), the sacrificial layer 31a is selectively removed with a solvent (polar solvent) that dissolves the sacrificial layer 31a. It becomes possible.

  In the present invention, examples of the polar solvent for dissolving the sacrificial layer 31a include a solvent containing water, an organic compound having a hetero atom (N, O, S, etc.) (an organic compound having a polar site). In the present invention, among the layers constituting the first organic compound layer 22a, the constituent material of the layer farthest from the first electrode is the sacrificial layer 31a at the etching rate for the polar solvent that dissolves the sacrificial layer 31a. It is preferable to select a material that can easily make a difference.

  As the constituent material of the release layer 32, a material that is highly soluble in a solvent in which the constituent material of the sacrificial layer 31a is low and that does not damage the sacrificial layer 31a or the first organic compound layer 22a when formed is selected. To do.

  Here, when a material having low solubility in water is used as the constituent material of the sacrificial layer 31a, a material that dissolves in water can be suitably used as the constituent material of the release layer 32. In such a case, specifically, a water-soluble inorganic material such as LiF or NaCl, or a water-soluble polymer such as polyvinyl alcohol (PVA) or polyvinyl pyrrolidone (PVP) can be used as a constituent material of the release layer 5. .

(5) Resist layer forming step (FIG. 2D)
Next, a resist layer 40 having an opening in a region where the first organic compound layer 22a is partially removed is formed on the release layer 32 (FIG. 2D).

  As a constituent material of the resist layer 40, a material having an etching rate with respect to the developing solution of the resist layer 40 larger than that of the peeling layer 32 is selected.

  Here, when the developer of the resist layer 40 dissolves the first organic compound layer 22a (a constituent material thereof) or causes the dissolution or alteration of the release layer 32, the release layer 32 and A protective layer is preferably provided between the resist layers 40. As a constituent material of the protective layer, inorganic materials such as silicon nitride and silicon oxide can be preferably used. By using the protective layer, dissolution and alteration of the peeling layer 32 and the first organic compound layer 22a caused by the formation of the resist layer 40 can be suppressed, and as a constituent material of the resist layer 40 formed on the peeling layer 32 The choice of materials that can be used can be increased.

By the way, this process is performed by the process shown by the following (5-1) thru | or (5-3), for example.
(5-1) Resist film formation step (5-2) Exposure step (5-3) Development step

  In the case where the resist layer 40 having a predetermined pattern is formed by adopting the photolithography method, the above processes (5-1) to (5-3) are indispensable. The method for forming the layer 40 is not limited to the photolithography method. For example, an ink jet method or a printing method may be employed.

(6) Processing step of the first organic compound layer (FIG. 2 (e))
Next, by using the resist layer 40 as a mask, the peeling layer 32, the sacrificial layer 31a, and the first organic compound layer 22a provided in a region where the resist layer 40 is not formed are partially removed, so that the peeling layer 32, the sacrificial layer The layer 31a and the first organic compound layer 22a are sequentially processed. Thereby, the first electrode 21b is exposed (FIG. 2E).

  As a processing method of the peeling layer 32, the sacrificial layer 31a, and the first organic compound layer 22a, dry etching or wet etching is exemplified. At the stage of completing this process, the first organic compound layer 22a having a predetermined pattern shape is formed.

  In addition, when performing this process, a part or all of the resist layer 40 may be removed. That is, at the stage where this process is completed, as shown in FIG. 2E, the resist layer 40 used as a mask may be etched and removed. If the resist layer 40 remains on the surface of the processed release layer 32 after removing the first organic compound layer 22a provided in the region where the resist layer 40 is not formed, the resist remaining in a separate process Layer 40 may be removed.

(7) Step of forming second organic compound layer and sacrificial layer (FIG. 2 (f))
Next, the second organic compound layer 22b and the sacrificial layer 32b are sequentially formed on the first electrode 21b exposed in the previous step (processing step of the first organic compound layer). In addition, since this process is a process of forming the 2nd organic compound layer 22b and the sacrificial layer 32b over the whole surface of the board | substrate 10, of the peeling layer 32 which remain | survived in the previous process (process of a 1st organic compound layer) A second organic compound layer 22b and a sacrificial layer 32b are also formed thereon (FIG. 2 (f)).

  The constituent material of the second organic compound layer 22b can be appropriately selected from known low molecular weight materials or high molecular weight materials, similarly to the first organic compound layer 22a.

  The second organic compound layer 22b is a single-layer film having at least a light-emitting layer or a laminated film composed of a plurality of layers. When the second organic compound layer 22b is a laminated film composed of a plurality of layers, the layers constituting the second organic compound layer 22b and other than the light emitting layer include a hole injection layer, a hole transport layer, an electron Examples include a transport layer and an electron injection layer.

  The second organic compound layer 22b can be formed by the method adopted when forming the first organic compound layer 22a.

  The constituent material of the sacrificial layer 31b formed in this step is preferably selected on the same basis as the sacrificial layer 31a formed on the first organic compound layer 22a, and is made of the same material as the sacrificial layer 31a. Is desirable.

  The sacrificial layer 31b formed in this step can be formed by the method employed when the sacrificial layer 31a is formed.

(8) Lift-off process (FIG. 2 (g))
Next, the release layer 32 is dissolved by bringing the release liquid into contact with the release layer 32. Thereby, the peeling layer 32 is removed, and the second organic compound layer 22b and the sacrificial layer 31b formed on the peeling layer 32 are removed (lifted off) (FIG. 2G).

  In addition, since each organic compound layer (22a, 22b) provided under the peeling layer 32 is protected by the sacrificial layer (31a, 31b), it is not affected by the peeling solution.

(9) Sacrificial layer removal step (FIG. 2 (h))
Next, the sacrificial layers (31a, 31b) formed on the organic compound layers (22a, 22b) are selectively dissolved with a polar solvent and removed from the organic compound layers (22a, 22b). (FIG. 2 (h)).

(10) Step of forming second electrode or the like (FIG. 2 (i))
Finally, the second electrode 23 is formed on each organic compound layer (22a, 22b). Thus, the basic configuration of the organic light emitting device is completed (FIG. 2 (i)).

  As a constituent material of the second electrode 23, a known electrode material such as a metal material such as aluminum or silver, a transparent electrode material such as indium tin oxide (ITO) or indium zinc oxide, or a laminated film thereof is used. be able to.

  In addition, it is preferable that the constituent material of the second electrode 23 is appropriately selected in consideration of a method of extracting light output from the organic compound layer. Here, in order to emit the light output from the organic compound layer to the outside, at least one of the first electrode (21a, 21b) and the second electrode 23 is an electrode made of a transparent or translucent material. Here, transparent means a material having a transmittance of 80% or more with respect to visible light, and translucent means a material having a transmittance of 20% or more and less than 80% with respect to visible light.

  In the present invention, a common layer may be formed as a common organic compound layer on each organic compound layer (22a, 22b) prior to the formation of the second electrode 23. The common layer is not particularly limited as long as it is a layer formed after the light emitting layer that needs to be patterned for each pixel. For example, when the first electrode (21a, 21b) is an anode, examples of the common layer include an electron transport layer and an electron injection layer. When the first electrode (21a, 21b) is a cathode, examples of the common layer include a hole transport layer and a hole injection layer.

  In the present invention, after the second electrode 23 is formed, a known sealing member (not shown) is preferably provided as appropriate in order to prevent moisture from entering the organic light emitting element from the outside.

  In the present embodiment, an organic light emitting device having two types of organic light emitting elements having different emission colors has been described as an example. However, the present invention is not limited to this, and an organic light emitting device including three or more types of organic light emitting elements is provided. The present invention can also be applied to a light emitting device.

For example, an organic light emitting device having three or more types of organic compound layers can be obtained by appropriately repeating a process similar to the process of patterning the first organic compound layer 22a with respect to the other organic compound layers. Specifically, after forming the first organic compound layer 22a and then forming the sacrificial layer 31a on the first organic compound layer 22a, the processes shown below may be repeated as appropriate.
・ Peeling layer forming process (Protective layer forming process)
・ Resist layer formation process ・ Exposure and development process ・ (Protective layer) Release layer, sacrificial layer, organic compound layer processing process ・ Other organic compound layer formation process ・ Sacrificial layer formation process ・ Lift-off process

  In addition, the manufacturing process of an organic light-emitting device provided with three types of organic light-emitting elements is demonstrated in detail in an Example.

  Hereinafter, the present invention will be described specifically by way of examples.

[Example 1]
According to the manufacturing process shown in FIG. 3, the organic light emitting device shown in FIG.

(1) Step of Forming Substrate with Electrode First, a reflective electrode was formed by depositing AlNd on the entire surface of the substrate 10 by sputtering. At this time, the thickness of the AlNd film was set to 100 nm. Next, an ITO film was formed on the reflective electrode by sputtering to form an ITO film. At this time, the thickness of the ITO film was 10 nm.

  Next, a laminated film composed of a reflective electrode (AlNd film) and an ITO film was patterned using a known photolithography method. Thereby, a plurality of first electrodes (21a, 21b, 21c) constituting the first organic light emitting element 20a, the second organic light emitting element 20b, or the third organic light emitting element 20c were formed (FIG. 3A). .

  The substrate 10 used in the present embodiment includes a base material (not shown) and a circuit (not shown) for driving each organic light emitting element (20a, 20b, 20c) provided on the base material. ) And an insulating layer (not shown) for covering this circuit. Although not shown in FIGS. 1B and 3, each first electrode (21a, 21b, 21c) is electrically connected to the circuit through a contact hole provided in a predetermined region of the insulating layer. Connected.

(2) Element isolation film and intervening layer formation step (FIG. 3A)
Next, a silicon oxide film was formed over the entire surface of the substrate 10 by plasma CVD to form a SiO ₂ film. At this time, the thickness of the SiO ₂ film was 100 nm. Next, a photoresist made of polyimide resin was applied and formed on the SiO ₂ film using a spin coater to form a resist film. At this time, the film thickness of the resist film was 1.4 μm. Next, a predetermined region of the resist film was exposed through a photomask, and developed to develop the resist film. Thereby, the resist film provided on the first electrodes (21a, 21b, 21c) was removed. Next, dry etching with carbon tetrafluoride plasma was performed to remove the SiO ₂ film provided on the first electrodes (21a, 21b, 21c), thereby patterning the SiO ₂ film.

  By the above, the area | region which provides each organic light emitting element (20a, 20b, 20c), ie, the element isolation film 11 which divides a light emission area | region, was formed (FIG. 3 (a)). Note that the resist film provided on the element isolation film 11 by dry etching using carbon tetrafluoride plasma described above has an element isolation film in a thickness range of 1.0 μm to 1.3 μm, although a part of the resist film is removed. 11 remained. Hereinafter, the resist film remaining on the element isolation film 11 in this step is referred to as an intervening layer 12.

(3) Step of forming the first organic compound layer (FIG. 3B)
Next, the first organic compound layer 22a including the blue light emitting layer was formed over the entire surface of the substrate 10 by a continuous film formation using a vacuum evaporation method (FIG. 3B). The first organic compound layer 22a is a stacked body in which a hole transport layer, a blue light emitting layer, and a hole block layer are sequentially stacked.

  First, of the two surfaces of the substrate 10, on the surface on which the first electrodes (21a, 21b, 21c) are formed, a hole transport layer was formed with a film thickness of 120 nm over the entire surface. Next, a blue light emitting layer containing a blue light emitting material was formed with a film thickness of 30 nm. Next, the condensed polycyclic hydrocarbon compound (Compound 1) shown below was formed into a film to form a hole blocking layer. At this time, the thickness of the hole blocking layer was 10 nm.

(4) Formation process of sacrificial layer Next, the phenanthroline derivative (compound 2) shown below was formed on the first organic compound layer 22a by a vacuum vapor deposition method to form a sacrificial layer 31a. At this time, the thickness of the sacrificial layer 31a was set to 40 nm.

(5) Release layer forming step (FIG. 3C)
Next, polyvinyl pyrrolidone (PVP), which is a water-soluble polymer material, and water were mixed to prepare an aqueous PVP solution. Next, the prepared PVP aqueous solution was applied onto the sacrificial layer 31a by spin coating, and then dried to form the release layer 32. At this time, the thickness of the release layer 32 was 500 nm (FIG. 3C).

(6) Resist Layer Formation Step Next, a commercially available photoresist material (manufactured by AZ Electronic Materials, product name “AZ1500”) is formed on the release layer 32 by spin coating, and the resist layer 40 is formed. Formed. At this time, the film thickness of the resist layer 40 was 1000 nm.

(7) Exposure / development process (FIG. 3D)
Next, the resist layer 40 is irradiated with light using a photomask having an opening in a region excluding a region where the first electrode 21a serving as a constituent member of the first organic light emitting element 20a is provided and a region around it. did. Next, the resist layer 40 was developed using a developer for the resist layer 40 (manufactured by AZ Electronic Materials, product name “312MIF”). By this development processing, the resist layer 40 was processed by selectively removing the resist layer 40 formed in the region excluding the region where the first electrode 21a is provided and the surrounding region (FIG. 3D )).

(8) Processing steps for organic compound layer (FIG. 3 (e))
Next, using the resist layer 40a remaining on the substrate 10 as a mask, the release layer 32 not covered with the resist layer 40a was removed by dry etching, thereby processing the release layer 32. At this time, the reaction gas was oxygen, the flow rate of the reaction gas was 20 sccm, the pressure in the apparatus was 8 Pa, and the output was 150 W.

  Next, under the same etching conditions as those for the peeling layer 32, the sacrificial layer 31a and the first organic compound layer 22a not covered with the peeling layer 32 are partially removed by dry etching, and each layer is processed. (FIG. 3 (e)). In this way, the first organic compound layer 22a provided on the predetermined first electrode (21b, 21c) was selectively removed to expose the predetermined first electrode (21b, 21c). Moreover, the resist layer 40a provided on the peeling layer 32 was completely removed when the processing (partial etching) of the first organic compound layer 22a was completed by the dry etching described above.

(9) Step of forming second organic compound layer Next, a hole transport layer, a green light emitting layer, and a hole blocking layer are formed by the same method as the first organic compound layer (continuous film formation using a vacuum deposition method). A second organic compound layer 22 b that was sequentially laminated was formed over the entire surface of the substrate 10. At this time, the film thicknesses of the hole transport layer, the green light emitting layer, and the hole blocking layer constituting the second organic compound layer 22b are 160 nm, 30 nm, and 10 nm, respectively, and the light emitting material contained in the green light emitting layer is a known green A luminescent material was obtained.

(10) Sacrificial layer forming step (FIG. 3F)
Next, the sacrificial layer 31b was formed by depositing the compound 2 on the second organic compound layer 22b by vacuum deposition (FIG. 3F). At this time, the thickness of the sacrificial layer 31b was set to 40 nm.

(11) Lift-off process (FIG. 3 (g))
Next, the substrate 10 formed up to the sacrificial layer 31b was immersed in water as a peeling solution for the peeling layer 32. Here, the etching rate for water of the release layer 32 made of water-soluble polyvinylpyrrolidone is 100 times or more larger than the etching rate for water of the sacrificial layers (31a, 31b) made of compound 2 (phenanthroline derivative). For this reason, the release layer 32 could be selectively dissolved. By dissolving the release layer 32 in this way, the layer formed on the release layer 32 was lifted off (FIG. 3G). In addition, in the stage which finished this process, on the sacrificial layer (31a, 31b) formed on each organic compound layer (22a, 22b), and on the 1st electrode 21c which comprises the 3rd organic light emitting element 20c. The formed sacrificial layer 31b remained (FIG. 3G).

(12) Step of forming release layer (FIG. 3 (h))
Next, polyvinyl pyrrolidone (PVP), which is a water-soluble polymer material, and water were mixed to prepare an aqueous PVP solution. Next, the prepared PVP aqueous solution was applied / formed over the entire surface of the substrate 10 by spin coating, and then dried to form a release layer 32 on the sacrificial layers (31a, 31b) (FIG. 3). (H)). At this time, the film thickness of the release layer 32 was 500 nm.

(13) Resist Layer Formation Step Next, a commercially available photoresist material (manufactured by AZ Electronic Materials, product name “AZ1500”) is formed on the release layer 32 by spin coating, and the resist layer 40 is formed. Formed. At this time, the film thickness of the resist layer 40 was 1000 nm.

(14) Exposure / development process (FIG. 3 (i))
Next, the resist layer 40 was irradiated with light using a photomask having an opening in a region where the first electrode 21c serving as a constituent member of the third organic light emitting element 20c is provided and a region around it. Next, the resist layer 40 was developed using a developer for the resist layer 40 (manufactured by AZ Electronic Materials, product name “312MIF”). By this development processing, the resist layer 40 was processed by selectively removing the resist layer 40 formed in the region where the first electrode 21c is provided and the peripheral region thereof (FIG. 3 (i)).

(15) Processing step for organic compound layer, etc. (FIG. 3 (j))
Next, using the resist layer 40b remaining on the substrate 10 as a mask, the release layer 32 not covered with the resist layer 40b was removed by dry etching, thereby processing the release layer 32. At this time, the reaction gas was oxygen, the flow rate of the reaction gas was 20 sccm, the pressure in the apparatus was 8 Pa, and the output was 150 W.

  Next, under the same etching conditions as those for the peeling layer 32, the sacrificial layer 31b and the second organic compound layer 22b not covered with the peeling layer 32 are partially removed by dry etching, and each layer is processed. (FIG. 3 (j)). Thus, the 2nd organic compound layer 22b provided on the 1st electrode 21c which comprises the 3rd organic light emitting element 20c was selectively removed, and the said 1st electrode 21c was exposed. Moreover, the resist layer 40b provided on the peeling layer 32 was completely removed when the processing (partial etching) of the second organic compound layer 22b was completed by the dry etching described above.

(16) Formation Step of Third Organic Compound Layer Next, a hole transport layer, a red light emitting layer, and a hole block layer are formed by the same method as the first organic compound layer (continuous film formation using a vacuum deposition method). A third organic compound layer 22c is sequentially formed over the entire surface of the substrate 10. At this time, the film thicknesses of the hole transport layer, the red light emitting layer, and the hole blocking layer constituting the third organic compound layer 22c are set to 200 nm, 30 nm, and 10 nm, respectively. A luminescent material was obtained.

(17) Sacrificial layer formation step (FIG. 3 (k))
Next, the sacrificial layer 31c was formed by depositing the compound 2 on the third organic compound layer 22c by vacuum deposition (FIG. 3K). At this time, the thickness of the sacrificial layer 31c was set to 40 nm.

(18) Lift-off process (FIG. 3 (l))
Next, the substrate 10 formed up to the sacrificial layer 31c was immersed in water which is a peeling solution of the peeling layer 32. As a result, the release layer 32 was dissolved and removed, and the layer formed on the release layer 32 was lifted off (FIG. 3 (l)).

(19) Sacrificial layer removal step (FIG. 3 (m))
Next, IPA solution was prepared by mixing isopropyl alcohol (IPA) and water so that IPA was 60% by weight. Next, the substrate 10 was immersed in the prepared IPA solution to remove the sacrificial layers (31a, 31b, 31c) provided on the organic compound layers (22a, 22b, 22c) (FIG. 3 (m )).

(20) Common Layer Formation Step Next, a compound 2 was formed on the organic compound layers (22a, 22b, 22c) to form a charge transport layer (electron transport layer, not shown). At this time, the thickness of the charge transport layer was set to 20 nm. Next, Compound 2 and cesium carbonate (Cs ₂ CO ₃ ) were co-evaporated on the charge transport layer to form an electron injection layer (not shown). At this time, the thickness of the electron injection layer was 29 nm. Note that a stacked body in which the charge transport layer and the electron injection layer are sequentially stacked functions as a common layer common to the respective organic light emitting elements (20a, 20b, 20c).

(21) Second electrode formation step (FIG. 3 (n))
Next, silver was formed on the common layer by sputtering, and the second electrode 24 was formed as a semitransparent electrode common to each organic light emitting element (20a, 20b, 20c) (FIG. 3 ( n)). At this time, the film thickness of the second electrode 24 was 16 nm.

(22) Sealing step Finally, in a nitrogen atmosphere, a sealing glass (not shown) is bonded to the substrate 10 using an adhesive made of an ultraviolet curable resin, and each organic light emitting element (20a, 20b, An organic light emitting device was obtained by sealing 20c).

(23) Evaluation of organic light-emitting device Ten organic light-emitting devices obtained by the above method were prepared and evaluated.

  When the surface of the organic light emitting element included in the obtained organic light emitting device was observed with a microscope, no cracks or peeling were observed in each of the organic compound layers (22a, 22b, 22c).

  Moreover, the thermal shock test was done about the obtained organic light-emitting device. Specifically, the obtained organic light-emitting device was subjected to 1000 cycles of heating and cooling in a temperature range of −30 ° C. to 85 ° C. As a result, no change in the organic compound layer was observed in the organic light emitting device after 1000 cycles.

[Comparative Example 1]
In Example 1 (2), after processing the SiO ₂ film by dry etching, the resist layer provided on the SiO ₂ film was removed using an organic amine-based stripping solution. Other than this, an organic light-emitting device was fabricated in the same manner as in Example 1.

  The obtained organic light emitting device was evaluated by the same method as in Example 1.

  As a result, in microscopic observation, cracks and peeling occurred at the end of the organic compound layer provided on the element isolation film. Here, when all the colors of the organic light emitting device of this comparative example were turned on to emit white light, a part of the organic light emitting elements included in the device was not lit. When the organic light emitting element which did not light here was examined, it was found that about 80% of the organic light emitting layer was generated due to peeling off of the organic compound layer and the scattered organic compound layer was the cause of non-light emission.

  Further, when a thermal shock test was performed, cracks and peeling of the organic compound layer provided on the element isolation film increased, and an enlargement of the non-light emitting region was observed in the light emitting portion adjacent to the cracks and peeling.

[Example 2]
In Example 1 (2), an organic light emitting device was obtained by the same method as in Example 1 except that the intervening layer was formed by the following process.

(Process for forming element isolation film and intervening layer)
First, an SiO ₂ film was formed over the entire surface of the substrate 10 by the same method as in Example 1 (2). Next, diamond-like carbon (hydrogenated amorphous carbon) was formed on the SiO ₂ film by a plasma CVD method using acetylene gas to form a DLC layer. At this time, the thickness of the DLC layer was set to 50 nm.

  Next, a resist film having an opening in a region where the first electrodes (21a, 21b, 21c) were provided was formed on the DLC layer by the same method as in Example 1 (2).

Next, the DLC layer and the SiO ₂ film not covered with the resist film were removed by dry etching using oxygen and carbon tetrafluoride plasma, thereby patterning the DLC layer and the SiO ₂ film.

Finally, the photoresist remaining on the DLC layer was removed using a stripping solution. Thus, the element isolation film 11 obtained by processing the SiO ₂ film and the intervening layer 12 provided on the element isolation film 11 and processed by the DLC layer were formed.

  The obtained organic light emitting device was evaluated by the same method as in Example 1. As a result of microscopic observation, no cracking or peeling was observed in the organic compound layers (22a, 22b, 22c) constituting the organic light emitting device of this example (Example 2).

  Further, even after the thermal shock test, the organic compound layers (22a, 22b, 22c) were not changed.

[Example 3]
In Example 1 (2), an organic light emitting device was obtained by the same method as in Example 1 except that the intervening layer was formed by the following process.

(Process for forming element isolation film and intervening layer)
First, an SiO ₂ film was formed over the entire surface of the substrate 10 by the same method as in Example 1 (2). Next, using a spin coater, a photoresist film made of polyimide resin was formed on the SiO ₂ film to form a resist film. At this time, the film thickness of the resist film was 1.4 μm. Next, it exposed and developed through the photomask which has an opening in the area | region which provides a 1st electrode (21a, 21b, 21c). Thus, the photoresist on the first electrodes (21a, 21b, 21c) was removed.

Next, dry etching using carbon tetrafluoride plasma was performed to remove the SiO ₂ film formed on the first electrodes (21a, 21b, 21c), and the SiO ₂ film was patterned. Next, dry etching using oxygen plasma was performed to oxidize the resist film formed on the SiO ₂ film remaining on the substrate 10 to form the intervening layer 12. Here, the film thickness of the intervening layer 12 made of an oxide of polyimide resin was in the range of 0.05 μm to 0.1 μm.

  The obtained organic light emitting device was evaluated by the same method as in Example 1. As a result of microscopic observation, no cracking or peeling was observed in the organic compound layers (22a, 22b, 22c) constituting the organic light emitting device of this example (Example 3).

  Further, even after the thermal shock test, the organic compound layers (22a, 22b, 22c) were not changed.

  From the above results, it was found that the organic light-emitting device of this example can emit light with high yield and stability compared to the organic light-emitting device of the comparative example. Further, it was found that the organic light emitting device of this example is a highly reliable organic light emitting device that is not easily deteriorated by temperature stress.

  1 (2): organic light emitting device, 10: substrate, 11: element isolation film, 12: intervening layer, 20a: first organic light emitting element, 20b: second organic light emitting element, 20c: third organic light emitting element, 21a ( 21b, 21c): first electrode, 22a: first organic compound layer, 22b: second organic compound layer, 22c: third organic compound layer, 23: second electrode, 31a (31b): sacrificial layer, 32: peeling Layer, 40 (40a, 40b): resist layer

Claims (5)

An organic light emitting device provided on a substrate;
An element isolation film provided on the substrate and around the organic light emitting element,
The organic light emitting device has a first electrode provided on the substrate, an organic compound layer provided on the first electrode, and a second electrode provided on the organic compound layer,
The organic compound layer covers at least a part of the surface of the element isolation film;
The organic compound layer is formed in a predetermined shape by a photolithography method,
In at least part of the region where the organic compound layer covers the element isolation film, an intervening layer is provided between the element isolation film and the organic compound layer,
The organic light-emitting device, wherein the intervening layer has any one of an organic compound having a hydrophobic site at a molecular end and an oxide thereof, and an organic compound having a hydrophobic substituent and an oxide thereof.   The organic light-emitting device according to claim 1, wherein the element isolation film is a member made of an inorganic material. An organic light emitting device provided on a substrate;
An element isolation film provided on the substrate and around the organic light emitting element,
The organic light emitting device has a first electrode provided on the substrate, an organic compound layer provided on the first electrode, and a second electrode provided on the organic compound layer,
The organic compound layer is a method of manufacturing an organic light emitting device that covers at least a part of the surface of the element isolation film,
Forming an element isolation film;
Forming an intervening layer in contact with the element isolation film;
And a method of forming an organic compound layer having a predetermined pattern shape by a photolithography method.   The method for manufacturing an organic light emitting device according to claim 3, wherein the intervening layer is made of a resist material used in the step of forming the element isolation film.   The method for manufacturing an organic light-emitting device according to claim 3, further comprising a step of oxidizing the surface of the intervening layer.

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