JP3781647B2 - Method for manufacturing electroluminescent device - Google Patents

Description

【０１４１】
ポジ型フォトレジスト液（東京応化社製；ＯＦＰＲ−８００）を２ｍｌとり、基体の中心部に滴下して、スピンコーティングを行った。５００ｒｐｍで１０秒間保持し、その後、２０００ｒｐｍで２０秒間保持して層形成した。この結果、膜厚は約１μｍとなった。８０℃で３０分間プリベークを行った。その後、アライメント露光機に露光マスクと共にセットし、バッファー層を除去したい部分に紫外線露光した。レジスト現像液（東京応化社製；ＮＭＤ−３）で２０秒間現像後、水洗し、露光部のフォトレジスト層および、バッファー層を除去した。１２０℃で３０分間ポストベークした後、アセトンでフォトレジスト層を全て除去し、アセトンに不溶のバッファー層を任意のパターンに形成した。
【０１４２】
（発光層の成膜）
第１の発光層としてバッファー層がパターニングされた基体上にポリパラフェニレンビニレン誘導体発光高分子ＭＥＨ−ＰＰＶ（以下の化学式（２）に示す。）の１ｗｔ％キシレン溶液を、を２ｍｌとり、基体の中心部に滴下して、スピンコーティングを行った。２０００ｒｐｍで１０秒間保持して層形成した。この結果、膜厚は８００オングストロームとなった。
【０１４３】
【化２】

【０１４４】
ポジ型フォトレジスト液（東京応化社製；ＯＦＰＲ−８００）を２ｍｌとり、基体の中心部に滴下して、スピンコーティングを行った。５００ｒｐｍで１０秒間保持し、その後、２０００ｒｐｍで２０秒間保持して層形成した。この結果、膜厚は約１μｍとなった。８０℃で３０分間プリベークを行った。その後、アライメント露光機に露光マスクと共にセットし、第１発光部以外の発光層を除去したい部分に紫外線露光した。レジスト現像液（東京応化社製；ＮＭＤ−３）で２０秒間現像後、水洗し、露光部のフォトレジスト層を除去した。１２０℃で３０分間ポストベークした後、トルエンでフォトレジスト層が除去された部分の発光層を除去した。アセトンでフォトレジストを除去した後、再度、ポジ型フォトレジスト液（東京応化社製；ＯＦＰＲ−８００）を２ｍｌとり、基体の中心部に滴下して、スピンコーティングを行った。５００ｒｐｍで１０秒間保持し、その後、２０００ｒｐｍで２０秒間保持して層形成した。この結果、膜厚は約１μｍとなった。８０℃で３０分間プリベークを行った。その後、アライメント露光機に露光マスクと共にセットし、第１発光部の幅よりも１０μずつ大きい幅のフォトレジスト層を残すように紫外線露光した。レジスト現像液（東京応化社製；ＮＭＤ−３）で２０秒間現像後、水洗し、露光部のフォトレジスト層を除去した。１２０℃で３０分間ポストベークし、第１発光部が第1発光部の幅よりも１０μずつ大きい幅を有するフォトレジスト層で保護された基体を得た。
【０１４５】
第２発光層としてポリパラフェニレンビニレン誘導体発光高分子ＭＥＨ−ＰＰＶの１ｗｔ％キシレン溶液を、を２ｍｌとり、基体の中心部に滴下して、スピンコーティングを行った。２０００ｒｐｍで１０秒間保持して層形成した。この結果、膜厚は８００オングストロームとなった。
【０１４６】
ポジ型フォトレジスト液（東京応化社製；ＯＦＰＲ−８００）を２ｍｌとり、基体の中心部に滴下して、スピンコーティングを行った。５００ｒｐｍで１０秒間保持し、その後、２０００ｒｐｍで２０秒間保持して層形成した。この結果、膜厚は約１μｍとなった。８０℃で３０分間プリベークを行った。その後、アライメント露光機に露光マスクと共にセットし、第１発光部と第２発光部以外の発光層を除去したい部分に紫外線露光した。レジスト現像液（東京応化社製；ＮＭＤ−３）で２０秒間現像後、水洗し、露光部のフォトレジストを除去した。１２０℃で３０分間ポストベークした後、トルエンでフォトレジストが除去された部分の発光層を除去した。アセトンでフォトレジストを除去した後、再度、ポジ型フォトレジスト液（東京応化製ＯＦＰＲ−８００）を２ｍｌとり、基体の中心部に滴下して、スピンコーティングを行った。５００ｒｐｍで１０秒間保持し、その後、２０００ｒｐｍで２０秒間保持して層形成した。この結果、膜厚は約１μｍとなった。８０℃で３０分間プリベークを行った。その後、アライメント露光機に露光マスクと共にセットし、第１発光部および第２発光部の幅よりも１０μずつ大きい幅でフォトレジスト層が残るように紫外線露光した。レジスト現像液（東京応化社製；ＮＭＤ−３）で２０秒間現像後、水洗し、露光部のフォトレジストを除去した。１２０℃で３０分間ポストベークし、第１発光部および第２発光部の幅よりも１０μずつ大きい幅を有するフォトレジストで保護された基体を得た。
【０１４７】
第３発光層としてポリパラフェニレンビニレン誘導体発光高分子ＭＥＨ−ＰＰＶの１ｗｔ％キシレン溶液を、を２ｍｌとり、基体の中心部に滴下して、スピンコーティングを行った。２０００ｒｐｍで１０秒間保持して層形成した。この結果、膜厚は８００オングストロームとなった。
【０１４８】
ポジ型フォトレジスト液（東京応化社製；ＯＦＰＲ−８００）を２ｍｌとり、基体の中心部に滴下して、スピンコーティングを行った。５００ｒｐｍで１０秒間保持し、その後、２０００ｒｐｍで２０秒間保持して層形成した。この結果、膜厚は約１μｍとなった。８０℃で３０分間プリベークを行った。その後、アライメント露光機に露光マスクと共にセットし、第１発光部、第2発光部、および第3発光部以外の発光層を除去したい部分に紫外線露光した。レジスト現像液（東京応化社製；ＮＭＤ−３）で２０秒間現像後、水洗し、露光部のフォトレジストを除去した。１２０℃で３０分間ポストベークした後、トルエンでフォトレジストが除去された部分の発光層を除去し、第１発光部、第2発光部、および第３発光部がフォトレジストで保護された基体を得た。その後、アセトンでフォトレジストをすべて除去し、パターニングされた発光層を露出させた。
１００℃で１時間乾燥した後、次いで、得られた基体上に、第２電極層（上部電極）としてＣａを５００オングストロームの厚みで蒸着し、さらに保護層としてＡｇを２５００オングストロームの厚みで蒸着し、ＥＬ素子を作製した。
【０１４９】
（ＥＬ素子の発光特性の評価）
ＩＴＯ電極側を正極、Ａｇ電極側を負極に接続し、ソースメーターにより、直流電流を印加した。１０Ｖ印加時に第１発光部、第2発光部、および第３発光部それぞれより発光が認められた。
【０１５０】
［比較例］
第１発光層および第２発光層の現像工程の後、フォトレジスト層の剥離工程と二次フォトレジスト層の形成、露光、および現像工程による発光層の再保護を行わなかったこと以外は実施例１と同様にＥＬ素子を作製した。第２発光層および第３発光層の現像時に、すでにパターニングされている発光層が溶出し、画素細りを生じた。
【０１５１】
【発明の効果】
本発明によれば、パターニングされた発光部が露出しないようにフォトレジスト層で覆うため、既に形成された発光部が後に塗布する発光層用塗工液と接触しないことから、発光部と発光層用塗工液とが接触することによって生じる混色や画素細りを防止することができるという効果を奏する。
【図面の簡単な説明】
【図１】本発明のＥＬ素子の製造方法における第１実施態様の第１の例を示す工程図である。
【図２】本発明のＥＬ素子の製造方法における第１実施態様の第２の例を示す工程図である。
【図３】本発明のＥＬ素子の製造方法における第２実施態様の第１の例を示す工程図である。
【図４】本発明のＥＬ素子の製造方法における第２実施態様の第２の例を示す工程図である。
【図５】従来のＥＬ素子の製造方法を示す工程図である。
【符号の説明】
１ … 基体
２ … 電極層
３ … バッファー層
４ … 第１発光層
４’ … 第１発光部
５ … 一次フォトレジスト層
５’ … 二次フォトレジスト層
８ … 第２発光層
８’ … 第２発光部
９ … 第３発光層
９’ … 第３発光部
ａ … 第１発光部の端部
ｂ … 第２発光部の端部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an EL element having an organic electroluminescent (hereinafter sometimes abbreviated as EL) layer, wherein the organic EL layer is formed in a pattern by a photolithography method. It is about.
[0002]
[Prior art]
In the EL element, holes and electrons injected from opposing electrodes are combined in the light emitting layer, and the fluorescent material in the light emitting layer is excited with the energy to emit light of a color corresponding to the fluorescent material. It attracts attention as a self-luminous planar display element. Among them, organic thin-film EL displays using organic substances as light-emitting materials have high light-emission efficiency such as high-luminance light emission even when the applied voltage is less than 10 V, and can emit light with a simple element structure. It is expected to be applied to advertisements that display these patterns in light emission and other simple display displays at low cost.
[0003]
In manufacturing a display using such an EL element, patterning of an electrode layer or an organic EL layer is usually performed. As a patterning method of this EL element, there are a method of evaporating a luminescent material through a shadow mask, a method of coating by ink jet, a method of destroying a specific luminescent dye by ultraviolet irradiation, a screen printing method and the like. However, these methods cannot provide an EL element manufacturing method that realizes all of light emission efficiency, high light extraction efficiency, simple manufacturing process, and high-definition pattern formation.
[0004]
As means for solving such a problem, a method for manufacturing an EL element in which a light emitting layer is formed by patterning using a photolithography method has been proposed. According to this method, as compared with the conventional patterning method by vapor deposition, a vacuum facility equipped with a highly accurate alignment mechanism or the like is unnecessary, so that it can be manufactured relatively easily and inexpensively. On the other hand, compared to the patterning method using the inkjet method, it is preferable in that it does not perform a pretreatment for a structure or a substrate that assists patterning, and the photolithography method is more preferable because of the discharge accuracy of the inkjet head. However, this method has an advantage that it can be said to be a preferable method for forming a finer pattern.
[0005]
As a method for forming a plurality of light emitting portions by such a photolithography method, for example, a method shown in FIG. 5 has been proposed.
[0006]
First, as shown in FIG. 5A, a patterned first electrode layer 32 is formed on a substrate 31, and a first light emitting layer coating solution 33 is applied on the entire surface thereof. Next, as shown in FIG. 5B, a positive resist 34 is applied over the entire surface, and as shown in FIG. 5C, only the portion where the first light emitting portion is formed is masked with the photomask 35, and the portions other than that portion are masked. Exposure with ultraviolet light 36.
[0007]
This is developed with a resist developer and washed with water, whereby the resist in the exposed portion is removed as shown in FIG. Further development with the solvent of the light emitting layer removes the exposed first light emitting layer 33 as shown in FIG. 5E, leaving the resist and the first light emitting portion 33 'covered with the resist.
[0008]
Next, as in the formation of the first light emitting portion 33 ′, a second light emitting layer coating solution 37 is applied to the entire surface as shown in FIG. At this time, as is apparent from FIG. 5 (f), there is a portion where the second light emitting layer coating liquid 37 applied to the entire surface and the first light emitting portion 33 ′ are in contact with each other. That is, as described above, the surface of the first light emitting portion 33 ′ remaining on the substrate 31 is covered with the positive resist, but the end a developed with the light emitting layer developer is exposed. Yes. Accordingly, when the second light emitting layer coating solution 37 is applied thereon, the first light emitting portion 33 'and the second light emitting layer coating solution come into contact with each other at the end a. At this time, the first light-emitting portion is eluted into the second light-emitting layer coating solution, thereby causing problems such as color mixing and pixel thinning.
[0009]
Further, as shown in FIG. 5 (g), a positive resist 34 is applied over the entire surface, and as shown in FIG. 5 (h), the portions where the first and second light emitting portions are formed are masked with the photomask 35, and the others are Exposure with ultraviolet light 36.
[0010]
When this is developed with a resist developer, washed with water, and further developed with the solvent of the light emitting layer, only the exposed second light emitting layer 37 is removed and the second light emitting portion coated with the resist 34 is removed as shown in FIG. 37 'was formed.
[0011]
Further, as in the formation of the first and second light emitting portions, a third light emitting layer coating solution 38 is applied as shown in FIG. Also at this time, as is clear from FIG. 5 (j), the first light emitting portion and the third light emitting layer coating solution are in contact with each other at the end a of the first light emitting portion 33 ′ formed first, Further, the second light emitting unit and the third light emitting layer coating solution are in contact with each other at the end b of the second light emitting unit 37 ′. At this time, similarly, the first light emitting portion 33 ′ and the second light emitting portion 37 ′ may elute in the third light emitting layer coating solution, and problems such as color mixing and pixel thinning may occur.
[0012]
Further, a positive resist 34 is applied to the entire surface, and the portions where the first, second, and third light emitting portions are formed are masked with a photomask 35 as shown in FIG. To do.
[0013]
When this is developed with a resist developer, washed with water, and developed with the solvent of the light emitting layer, only the exposed third light emitting layer 38 is removed as shown in FIG. 5 (l), and the portion covered with the resist remains. Further, when the stripping process is performed with a resist stripping solution, the upper layer is stripped from the portion where the resist is formed, and as shown in FIG. 5 (m), the first light emitting unit 33 ′, the second light emitting unit 37 ′, and the third layer The three color light emitting portions of the light emitting portion 38 'are formed to be exposed.
[0014]
Finally, as shown in FIG. 5 (n), when the second electrode layer 39 is formed on these light emitting portions, an EL element that emits EL light emission 40 below the figure can be manufactured.
[0015]
As described above, according to this photolithography method, the patterned end portion a of the first light emitting portion and the end portion b of the second light emitting portion are not covered with the photoresist layer. When the liquid is applied, there is a problem in that the patterned light-emitting portion elutes into the light-emitting layer coating solution to be applied later, resulting in color mixing and pixel thinning.
[0016]
[Problems to be solved by the invention]
The present invention has been made in view of the above-described problems, and has the advantages of the photolithographic method such as high luminous efficiency and high extraction efficiency, simple manufacturing process, and high-definition pattern formation, and pattern formation. It is a main object of the present invention to provide a method for manufacturing an EL element by a photolithography method that prevents color mixing between an end portion of a light emitting portion and a different light emitting layer to be laminated later, and further prevents pixel thinning.
[0017]
[Means for Solving the Problems]
  In order to achieve the above object, according to the present invention, as described in claim 1, a light emitting layer of a different kind is patterned a plurality of times on a substrate on which an electrode layer is formed using a photolithography method. In the method of manufacturing an EL element in which a plurality of types of light emitting portions are formed on the substrate, a light emitting layer and a light emitting layer are formed on the substrate.onceForming the photoresist layer in this order; andonceThe portion of the photoresist layer corresponding to the predetermined light-emitting portiononceA step of developing after pattern exposure so that the photoresist layer remains; andonceBy removing the exposed light-emitting layer after removing the photoresist layerForming a light emitting portion surface covered with the primary photoresist layer and an exposed light emitting end surface not covered with the primary photoresist layer;the aboveLight emitting part surface and light emitting end surfaceTo coversecondaryA step of forming a photoresist layer;surfaceandAbove light emissionedgesurfaceTo prevent exposuresecondaryAnd a step of developing after pattern exposure of the photoresist layer.
[0018]
  In the present invention, the patterned light emitting part is not exposed.secondarySince it is covered with a photoresist layer, the already formed light emitting part does not come into contact with the light emitting layer coating liquid to be applied later, thereby preventing pixel thinning and color mixing caused by contact between the light emitting part and the light emitting layer coating liquid. can do.
[0019]
  The present invention further includesAs described in claim 2,In the EL element manufacturing method for forming a plurality of types of light-emitting portions on the substrate by patterning a plurality of types of light-emitting layers on the substrate on which the electrode layer is formed, using a photolithography method multiple times. A step of forming a light emitting layer and a primary photoresist layer on the substrate in this order, and pattern exposure so that a portion of the primary photoresist layer corresponding to a predetermined light emitting portion remains on the primary photoresist layer. Then, the step of developing and the light-emitting portion surface covered with the primary photoresist layer and the primary photoresist layer are not covered by removing the exposed light-emitting layer by removing the primary photoresist layer. A step of forming an exposed light emitting end surface, and peeling off the primary photoresist layer remaining on the light emitting portion to expose the light emitting portion. A step of forming a secondary photoresist layer on the substrate on which the exposed light emitting part is formed so as to cover the light emitting part, and so that the surface of the light emitting part and the surface of the light emitting end are not exposed. And a step of developing the second photoresist layer after pattern exposure, and a method for producing an EL element.
This was formed earlieronceOn top of the photoresist layersecondaryAfter applying the photoresist,secondaryIt may be difficult to form a photoresist layer well. Therefore in advanceonceAfter removing the photoresist layer, a photoresist layer is formed on the entire surface.
[0020]
  In the present invention, a plurality of types of light-emitting layers are patterned on a substrate on which an electrode layer is formed by using a photolithography method a plurality of times on the substrate. In the method for manufacturing an EL element for forming a light emitting part of the above, a light emitting layer and a light emitting layer on the substrateonceForming the photoresist layer in this order; andonceThe portion corresponding to all the light emitting portions with respect to the photoresist layeronceA step of developing after pattern exposure so that the photoresist layer remains; andonceBy removing the exposed light emitting layer by removing the photoresist layer,Forming a light emitting portion surface covered with the primary photoresist layer and an exposed light emitting end surface not covered with the primary photoresist layer;the aboveLight emitting part surface and light emitting end surfaceTo coversecondaryA step of forming a photoresist layer and a predetermined light emitting portion;surfaceAnd givenLight emissionedgesurfaceTo prevent exposuresecondaryDevelop after pattern exposure of photoresist layerTo remove the primary photoresist layer and the secondary photoresist layer other than the predetermined light emitting portion.The primary photoresist layer andsecondaryAnd a step of removing the exposed light-emitting portion by removing the photoresist layer.
[0021]
Also in this case, similarly to the invention described in claim 1, the patterned light emitting portion is not exposed.secondarySince it is covered with the photoresist layer, the already formed light-emitting part does not come into contact with the light-emitting layer coating liquid to be applied later, so that color mixing caused by contact between the light-emitting part and the light-emitting layer coating liquid can be prevented. it can. And when developing a photoresist layer further, an electrode layer will always be in the state covered with the light emission part. Therefore, even when an organic EL layer such as a buffer layer is formed on the electrode layer, such an organic EL layer does not come into contact with the developer for the photoresist layer. Even if it is a soluble organic EL layer, it has the advantage that it can be used.
[0022]
  In the present invention, as further described in claim 4,In the EL element manufacturing method for forming a plurality of types of light-emitting portions on the substrate by patterning a plurality of types of light-emitting layers on the substrate on which the electrode layer is formed, using a photolithography method multiple times. A step of forming a light emitting layer and a primary photoresist layer on the substrate in this order, and pattern exposure so that a portion of the primary photoresist layer corresponding to all the light emitting portions remains with respect to the primary photoresist layer. Then, the developing step and the light emitting layer exposed by removing the primary photoresist layer are removed to cover the light emitting portion surface covered with the primary photoresist layer and the primary photoresist layer. A step of forming an exposed light emitting end surface that is not exposed, and removing the primary photoresist layer remaining on all the light emitting portions. A step of exposing all the light emitting portions, a step of forming a secondary photoresist layer on the substrate on which the exposed light emitting portions are formed so as to cover the light emitting portions, a predetermined light emitting portion surface, and a predetermined light emitting portion Removing the secondary photoresist layer other than the predetermined light emitting portion by pattern exposure of the secondary photoresist layer so as not to expose the surface of the light emitting edge, and developing the secondary photoresist layer; And a step of removing a light emitting portion exposed by removing the light emitting portion.
This was formed earlier as in the case of claim 2 above.onceOn top of the photoresist layersecondaryAfter applying the photoresist,secondaryThis is because it is difficult to satisfactorily form a photoresist layer, and thus problems caused by the failure to form a favorable photoresist layer can be solved.
[0023]
In the invention described in any one of claims 1 to 4, as described in claim 5, the step of removing the light emitting layer or the light emitting portion exposed by removing the photoresist layer. However, it is preferable to be a step of removing by dry etching. By using the method of removing the light emitting layer by dry etching in this way, it becomes possible to form a higher definition pattern.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
The EL device manufacturing method of the present invention can be roughly divided into two embodiments. Hereinafter, the EL device manufacturing method of the present invention will be described in detail for each embodiment.
[0025]
A. First embodiment
In the first embodiment of the present invention, a plurality of types of light emitting portions are formed on the substrate by patterning a plurality of types of light emitting layers on the substrate on which the electrode layer is formed, using a photolithography method multiple times. The method of manufacturing an EL element that includes at least the following steps.
[0026]
(1) Step of forming a light emitting layer and a photoresist layer in this order on a substrate (light emitting layer and primary photoresist layer forming step)
(2) Step of developing after pattern exposure so that a portion of the photoresist layer corresponding to the predetermined light emitting portion remains on the photoresist layer (primary photoresist layer developing step)
(3) A step of forming a light emitting part whose surface is covered with a photoresist layer by removing the exposed light emitting layer after removing the photoresist layer (light emitting layer developing step)
(4) Step of forming a photoresist layer on the substrate so as to cover the light emitting portion (secondary photoresist layer forming step)
(5) A step of developing the photoresist layer after pattern exposure so that the light emitting portion and the end thereof are not exposed (secondary photoresist layer developing step)
For each of these steps, first, the first example of the present embodiment shown in FIG. 1 will be used to briefly explain the formation of the first light emitting portion (FIGS. 1A to 1E).
[0027]
In the first example of this embodiment, first, as shown in FIG. 1A, the first light emission is performed on the first electrode layer 2 patterned on the substrate 1 and the buffer layer 3 formed thereon. The layer coating solution is applied to the entire surface using a spin coating method or the like. The first light emitting layer 4 is formed by drying and curing the first light emitting layer coating solution applied over the entire surface. Then, a positive photoresist is applied on the entire surface of the first light emitting layer 4 to form a primary photoresist layer 5 (light emitting layer and primary photoresist layer forming step).
[0028]
Next, the ultraviolet light 7 is pattern-irradiated using the primary photomask 6 so that the portion corresponding to the first light emitting portion is not exposed (FIG. 1A). The exposed portion of the primary photoresist layer 5 is developed with a photoresist developer and washed with water, whereby the exposed primary photoresist layer 5 is removed (primary photoresist layer developing step).
[0029]
Further, by developing with a light emitting layer developer, only the portion of the light emitting layer 4 not covered with the primary photoresist layer 5 is removed (FIG. 1B, light emitting layer developing step).
[0030]
Then, as shown in FIG. 1 (c), a positive photoresist is further applied over the entire surface so as to form a secondary photoresist layer 5 '(secondary photoresist layer forming step).
[0031]
Next, exposure is performed with ultraviolet rays 7 using a secondary photomask 6 ′ wider than the primary photomask 6 masked with the primary photoresist layer shown in FIG. 1A (FIG. 1D). Then, the exposed portion of the secondary photoresist layer 5 is developed with a photoresist developer and washed with water, thereby covering the first light emitting portion 4 ′ and its end a as shown in FIG. Next, a photoresist layer 5 ′ is formed (secondary photoresist layer developing step).
[0032]
As described above, when patterning one light emitting layer, the photoresist portion of the first light emitting portion 4 ′ is formed into a photoresist by performing the photoresist development process twice for the primary photoresist layer and the secondary photoresist layer. It can be set as the application | coating process of the coating liquid for 2nd light emitting layers for the following 2nd light emission part formation in the state coat | covered with the layer. Therefore, even if the next coating solution for the second light emitting layer is applied, problems such as color mixing do not occur.
[0033]
FIG. 2 shows the process up to the formation of the first light emitting portion in the second example of the present embodiment (FIGS. 2A to 2E). In this example, the process of FIG. 1B, that is, the process of developing the primary photoresist layer 5 and developing the first light emitting layer (light emitting layer developing process) is exactly the same (see FIG. 2B). ). In this example, a step of peeling the developed primary photoresist layer 5 is performed next (primary resist peeling step, see FIG. 2C). Next, a secondary photoresist layer 5 ′ is formed on the entire surface of the substrate from which the primary photoresist layer is completely removed and the first light emitting portion 4 ′ is exposed, and a secondary photomask is formed in the same manner as in the example of FIG. 6 'is exposed (FIG. 2D) to form a wide secondary photoresist layer 5' so that the end a of the first light emitting portion 4 'is not exposed. The state is covered with 5 '(FIG. 2 (e)).
[0034]
In the method of this example, it is necessary to perform an extra step of the photoresist layer peeling step between the light emitting layer developing step and the secondary photoresist layer forming step, but it has already been formed as in the example shown in FIG. Since the photoresist layer is not formed again on the existing photoresist layer, the secondary photoresist layer can be easily formed.
[0035]
Next, formation of the second light-emitting portion will be described using the first example shown in FIG. 1 (FIGS. 1 (f) to (j)). The second light emitting part can also be formed by performing the same process as the method for forming the first light emitting part on the second light emitting layer. At this time, the end a of the first light emitting part and the second light emitting part are formed. The third light emitting layer coating solution can be applied in a state where the end b of the part is covered, and color mixing can be prevented.
[0036]
That is, first, the second light emitting layer 8 is formed by the same spin coating or the like, and then the step of forming the primary photoresist layer 5 is performed (light emitting layer and primary photoresist layer forming step, FIG. 1 (f)). Next, pattern exposure is performed using a primary photomask 6 that masks a portion corresponding to the first light-emitting portion and a portion corresponding to the second light-emitting portion (FIG. 1 (f)). Thereafter, the primary photoresist layer is developed with a photoresist developer (primary photoresist layer developing step), and the exposed second light emitting layer is developed (light emitting layer developing step, FIG. 1 (g)). Next, a secondary photoresist layer 5 ′ is overlaid (secondary photoresist layer forming step, FIG. 1 (h)). Similarly, pattern exposure is performed using a wide secondary photomask 6 ′ and development is performed, so that the end a of the first light-emitting portion 4 ′ and the end b of the second light-emitting portion 8 ′ are subjected to secondary photo. It is formed so as to be covered with the resist layer 5 ′ (secondary photoresist layer developing step, FIG. 1 (j)). Therefore, when the third light emitting layer coating liquid is applied next to form the third light emitting layer 9 (FIG. 1 (k)), no color mixing occurs with the first light emitting part and the second light emitting part.
[0037]
Next, a second example of the formation of the second light emitting unit will be described (FIGS. 2 (f) to (j)). In the second example, in the case of forming the second light emitting part, a photoresist layer peeling process is performed between the light emitting layer developing process and the secondary photoresist layer forming process, as in the case of the first light emitting part. Is.
[0038]
First, similarly to the first example, the second light emitting layer 8 and the primary photoresist layer 5 forming step were performed (FIG. 2F), and the primary photoresist layer developing step and the second light emitting layer developing step were performed. The state is shown in FIG. 2G (corresponding to FIG. 1G). In this state, the primary photoresist layer 5 and the secondary photoresist layer 5 'are peeled off (photoresist layer peeling step, FIG. 2 (h)). Next, a secondary photoresist layer 5 ′ is formed, and exposure and development are performed using a wide secondary photomask 6 ′ (FIG. 2 (i)), whereby the end portion a is formed by the secondary photoresist layer 5 ′. The first light-emitting portion 4 ′ covered up to the end and the second light-emitting portion 8 ′ covered up to the end b are formed (secondary photoresist layer forming step, secondary photoresist layer developing step, FIG. 2 (j) ).
[0039]
In the second example shown in FIG. 2, as in the case of the first light emitting layer, the photoresist layer peeling step is performed in advance and then the secondary photoresist layer forming step is performed. As described above, the secondary photoresist layer is not further laminated on the primary photoresist layer. Therefore, there is an advantage that the secondary photoresist layer can be easily formed.
[0040]
Finally, in the example shown in FIG. 1 and the example shown in FIG. 2 as well, the light emitting layer forming step and the photoresist forming step for forming the third light emitting layer 9 and the photoresist 5 are performed (FIG. 1 (k), FIG. 2 (k)). Then, the photoresist is exposed and developed, and after the third light emitting layer developing step is performed, the photoresist is peeled off, whereby the first light emitting unit 4 ′, the second light emitting unit 8 ′, and the third light emitting unit 9 are removed. 'Is formed (FIG. 1 (l)). Finally, as shown in FIG. 1 (m), the second electrode layer 10 is formed on these light emitting portions, and an EL element that emits EL light can be manufactured below the figure.
[0041]
Hereafter, each process of the manufacturing method of such an EL element of this embodiment is demonstrated in detail.
1. Light emitting layer and primary photoresist layer forming process
In this embodiment, first, a light emitting layer and photoresist layer forming step is performed. As shown in FIG. 1 and FIG. 2, when the light emitting layer is the first light emitting layer, the first light emitting layer is applied by applying the first light emitting layer coating liquid onto the substrate on which the normal electrode layer is formed. Form.
[0042]
The substrate used in the present embodiment is such that at least the electrode layer is formed as described above, but in the present embodiment, the substrate is not limited to this, and other organic EL layers such as a buffer layer may be used. It is also possible to use the formed one.
[0043]
However, in this embodiment, as shown in FIGS. 1D to 1E, when developing the secondary photoresist layer 5 ′, the buffer layer 3 must be exposed. . Therefore, in this embodiment, the organic EL layer such as the buffer layer formed at this position is preferably an organic EL layer that does not elute into the developer or solvent of the photoresist layer. Specifically, a buffer layer using a sol-gel reaction liquid, a photocurable resin, or a thermosetting resin can be given. In other words, an uncured sol-gel reaction solution, a photocurable resin or a thermosetting resin added with an additive for functioning as a buffer layer to form a buffer layer forming coating solution, a sol-gel reaction solution, a photocuring agent Insoluble in a solvent by curing a buffer layer forming coating solution that is made to function as a buffer layer by modifying the curable resin or the thermosetting resin itself. Such as a simple buffer layer.
[0044]
Hereinafter, each structure used for such a light emitting layer and a photoresist layer formation process is demonstrated concretely.
[0045]
a. Substrate
The substrate used in this embodiment is not particularly limited as long as it has high transparency, and an inorganic material such as glass, a transparent resin, or the like can be used.
[0046]
The transparent resin is not particularly limited as long as it can be formed into a film, but a polymer material having high transparency, relatively high solvent resistance and heat resistance is preferable. Specifically, polyethersulfone, polyethylene terephthalate (PET), polycarbonate (PC), polyetheretherketone (PEEK), polyvinyl fluoride (PFV), polyacrylate (PA), polypropylene (PP), polyethylene (PE) , Amorphous polyolefin, or fluorine-based resin.
[0047]
b. Electrode layer
An electrode layer is formed on the substrate as described above. Such an electrode layer is not particularly limited as long as it is usually used for an EL element. In addition, the electrode layer provided in advance on the substrate may be referred to as a first electrode layer, and the electrode layer provided after the organic EL layer is formed may be referred to as a second electrode layer. These electrode layers are composed of an anode and a cathode, and either the anode or the cathode is transparent or translucent, and the anode is preferably a conductive material having a large work function so that holes can be easily injected. . A plurality of materials may be mixed. Each of the electrode layers preferably has a resistance as small as possible. Generally, a metal material is used, but an organic material or an inorganic compound may be used.
[0048]
c. Luminescent layer coating solution
In this embodiment, the light emitting layer is formed on the substrate by applying a coating solution for the light emitting layer on the substrate on which the electrode layer is formed at least and drying it.
[0049]
Such a light emitting layer coating solution is usually composed of a light emitting material, a solvent, and additives such as a doping agent. In this embodiment, since the EL element manufacturing method forms a plurality of types of light emitting portions on a substrate by patterning different types of light emitting layers using a photolithography method a plurality of times, a plurality of types are used. A color light emitting layer is formed. Therefore, a plurality of types of light emitting layer coating liquids are used.
[0050]
The method for applying the light emitting layer coating solution onto the substrate is not particularly limited as long as it can be applied to the entire surface. For example, spin coating, casting, dipping, bar It is applied by a coating method such as a coating method, a blade coating method, a roll coating method, a gravure coating method, a flexographic printing method, or a spray coating method.
[0051]
The applied light emitting layer coating solution is dried and solidified by heating or the like to form a light emitting layer. Hereinafter, each material which comprises these light emitting layer coating liquids is demonstrated.
[0052]
I. Luminescent material
The light emitting material used in this embodiment is not particularly limited as long as it contains a material that emits fluorescence and emits light, and may also have a light emitting function, a hole transport function, and an electron transport function. In the present embodiment, the material for forming the light emitting layer is insoluble in a photoresist solvent, a photoresist developer, and a photoresist stripper, which will be described later, because the light emitting layer is patterned by photolithography as described later. Some materials are preferred. In this case, it is preferable to use a material insoluble in the solvent used for forming the light emitting layer as the photoresist used when the light emitting layer is patterned by a photolithography method.
[0053]
Examples of such a light emitting material include a dye material, a metal complex material, and a polymer material.
[0054]
(1) Dye-based materials
Examples of dye-based materials include cyclopentamine derivatives, tetraphenylbutadiene derivatives, triphenylamine derivatives, oxadiazol derivatives, pyrazoloquinoline derivatives, distyrylbenzene derivatives, distyrylarylene derivatives, silole derivatives, thiophene ring compounds, pyridine rings Examples thereof include compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives, trifumanylamine derivatives, oxadiazole dimers, pyrazoline dimers, and the like.
[0055]
(2) Metal complex materials
Examples of metal complex materials include aluminum quinolinol complex, benzoquinolinol beryllium complex, benzoxazole zinc complex, benzothiazole zinc complex, azomethyl zinc complex, porphyrin zinc complex, europium complex, etc. Examples thereof include a metal complex having a rare earth metal such as Tb, Eu, or Dy and having a oxadiazole, thiadiazole, phenylpyridine, phenylbenzimidazole, quinoline structure, or the like as a ligand.
[0056]
(3) Polymeric material
Polymer materials include polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, the above dye bodies, and metal complex light emitting materials. Can be mentioned.
[0057]
In this embodiment, from the viewpoint of taking advantage of the ability to accurately form a light emitting layer by a photolithography method using a light emitting layer coating solution, a material using the above polymer material as a light emitting material is used. More preferred.
[0058]
II. solvent
As is apparent from the examples shown in FIGS. 1 and 2, the light emitting layer coating solution may be applied onto the photoresist layer. Therefore, it is preferable to select a solvent having a solubility in a photoresist at 25 ° C. and 1 atm of 0.001 (g / g solvent) or less as the solvent used in the light emitting layer coating solution, and more preferably 0 It is preferable to select a solvent of 0.0001 (g / g solvent) or less. For example, when a buffer layer described later is dissolved in a polar solvent such as water or DMF, DMSO, or alcohol, and the photoresist is a general novolac positive resist, isomers of benzene, toluene, xylene and mixtures thereof, mesitylene , Tetralin, p-cymene, cumene, ethylbenzene, diethylbenzene, butylbenzene, chlorobenzene, dichlorobenzene isomers and mixtures thereof, anisole, phenetol, butylphenyl ether, tetrahydrofuran, 2- Ether solvents such as butanone, 1,4-dioxane, diethyl ether, diisopropyl ether, diphenyl ether, dibenzyl ether, diglyme, dichloromethane, 1,1-dichloroethane, 1,2-diethyl Examples include chloro-based solvents such as chloroethane, trichloroethylene, tetrachloroethylene, chloroform, carbon tetrachloride, 1-chloronaphthalene, cyclohexanone, etc., but other solvents that satisfy the conditions can be used. It may be.
[0059]
In addition, when used with a buffer layer that is soluble in a solvent as described later, in order to prevent the buffer layer and the light emitting layer material from being mixed or dissolved during the formation of the light emitting layer, the original light emitting characteristics of the light emitting material are maintained It is desirable not to dissolve the buffer layer.
[0060]
From such a viewpoint, it is preferable to select a solvent for the light emitting layer coating solution having a solubility in the buffer layer material of 25 ° C. or less and 0.001 (g / g solvent) or less at 1 atm. It is preferable to select a solvent of 0.0001 (g / g solvent) or less.
[0061]
III. Additive
In addition to the light emitting material and the solvent as described above, various additives can be added to the light emitting layer coating solution used in this embodiment. For example, a doping material may be added for the purpose of improving the light emission efficiency in the light emitting layer or changing the light emission wavelength. Examples of the doping material include perylene derivatives, coumarin derivatives, rubrene derivatives, quinacridone derivatives, squalium derivatives, porphyrene derivatives, styryl dyes, tetracene derivatives, pyrazoline derivatives, decacyclene, phenoxazone, and the like.
[0062]
d. Photo resist
In this embodiment, a primary photoresist layer is formed by applying a photoresist to the entire surface of the substrate on which the light emitting layer is formed.
[0063]
In this case, the method for applying the photoresist is not particularly limited as long as it is generally a method for applying the coating liquid to the entire surface. Specifically, the spin coating method, the casting method, the dipping method, the bar coating, and the like. Coating methods such as a method, a blade coating method, a roll coating method, a gravure coating method, a flexographic printing method, and a spray coating method are used.
[0064]
In this embodiment, the primary photoresist layer is thus formed on the light emitting layer, and the light emitting layer is patterned by a photolithography method. This photolithography method is a method of forming an arbitrary pattern according to the light irradiation pattern by utilizing the change in solubility of the light irradiation portion of the film by light irradiation.
[0065]
The photoresist that can be used in this embodiment is not particularly limited, whether it is a positive type or a negative type, but one that is insoluble in a solvent used for forming an organic EL layer such as a light-emitting layer. preferable.
[0066]
Specific examples of the photoresist that can be used include novolak resin-based, rubber + bisazide-based, and the like.
[0067]
e. Photoresist solvent
In this embodiment, as the photoresist solvent used when coating the photoresist, the above-described organic EL layer such as the light emitting layer and the photoresist material are prevented from being mixed or dissolved during the photoresist film formation, In order to maintain the original light emission characteristics, it is desirable to use a material that does not dissolve the organic EL material such as the light emitting layer material. Considering this point, the photoresist solvent that can be used in this embodiment has a solubility in an organic EL layer forming material such as a light emitting layer forming material of 0.001 (g / g at 25 ° C. and 1 atm). g solvent) The following solvent is preferably selected, more preferably 0.0001 (g / g solvent) or less is selected.
[0068]
For example, as a photoresist solvent that can be used when the buffer layer forming material is dissolved in an aqueous solvent and the light emitting layer is dissolved in an aromatic non-polar organic solvent, ketones such as acetone and methyl ethyl ketone are used. Cellosolve acetates such as propylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether Cellosolves such as ethylene glycol monoethyl ether, methanol, ethanol, 1-butanol, 2-butanol , Alcohols such as cyclohexanol, ester solvents such as ethyl acetate and butyl acetate, cyclohexane, decalin and the like can be used. It may be a solvent.
[0069]
2. Primary photoresist layer development process
Next, in the present embodiment, a primary photoresist layer developing step is performed in which pattern exposure is performed and development is performed so that a portion of the photoresist layer corresponding to a predetermined light emitting portion remains on the primary photoresist layer. It is.
[0070]
In this step, the primary photoresist layer is first exposed through a photomask. Since this exposure method and the like are the same as the conventional exposure method, description thereof is omitted here, but the photomask is formed so that the photoresist layer of the portion where the first light emitting portion is formed remains. A photomask is used. Specifically, in the example shown in FIG. 1 or FIG. 2, since a positive type photoresist is used, a photomask that shields light from a portion corresponding to the first light emitting portion is used. When a negative photoresist is used, a photomask that exposes only the portion corresponding to the first light emitting portion is used.
[0071]
In addition, although the case where it exposes in pattern shape by drawing with a laser beam etc., for example is considered, this embodiment includes such a case.
[0072]
Then, after the pattern exposure is performed, the first photoresist layer is developed, and as a result, the photoresist layer is patterned so that the first photoresist layer remains on the first light emitting portion.
[0073]
Hereinafter, the developer used for patterning the photoresist layer in this step will be described.
[0074]
(Photoresist developer)
The photoresist developer that can be used in this embodiment is not particularly limited as long as it does not dissolve the material for forming the light emitting layer. Specifically, a commonly used organic alkaline developer can be used, but in addition, an inorganic alkali or an aqueous solution capable of developing a photoresist layer can be used. It is desirable to wash with water after developing the photoresist layer.
[0075]
The developer that can be used in this embodiment is preferably a developer having a solubility in the light emitting layer forming material of 0.001 (g / g developer) or less at 25 ° C. and 1 atm. Is to select a developing solution of 0.0001 (g / g developing solution) or less.
[0076]
3. Light emitting layer development process
In this embodiment, the step of forming a light emitting part whose surface is covered with the photoresist layer is performed by removing the exposed light emitting layer by removing the primary photoresist layer in this way.
[0077]
In this light emitting layer development step, a wet method using a solvent that dissolves the light emitting layer and a dry method using dry etching can be used, but in this embodiment, a dry method free from problems such as color mixing is used. It is preferable. Hereinafter, each method will be described.
[0078]
(Wet method)
In this case, the wet method is a method in which the light emitting layer is dissolved and removed using a solvent capable of dissolving or peeling the light emitting layer without removing the photoresist. As the solvent that can be used in this case, the solvent of the light emitting layer coating solution described above can be used, and other solvents can be selected as long as they satisfy the above conditions.
[0079]
Moreover, you may make it carry out in an ultrasonic bath, when removing using this solvent. By using an ultrasonic bath in this way, it is possible to perform patterning with high accuracy without causing defects such as thinning of the pattern of the light emitting layer and outflow of the light emitting layer, and it is possible to perform patterning with high accuracy in a short time. This is preferable.
[0080]
In this embodiment, it is preferable that the ultrasonic conditions used in the ultrasonic bath be set at 25 ° C. and at an oscillation frequency of 20 to 100 kilohertz for 0.1 to 60 seconds. Highly accurate patterning is possible in a short time.
[0081]
(Dry method)
On the other hand, the dry method is a method of removing a portion of the light emitting layer where the photoresist is removed by dry etching.
[0082]
Usually, since the photoresist layer is formed much thicker than the light emitting layer, the light emitting layer can be removed by dry etching as a whole.
[0083]
In this case, the thickness of the photoresist layer is preferably in the range of 0.1 to 10 μm, and more preferably in the range of 0.5 to 5 μm. With such a film thickness, dry etching with high processing accuracy can be performed while maintaining the resist function of the photoresist.
[0084]
Thus, if dry etching is used, it becomes possible to make the edge of etching more sharp, so it becomes possible to narrow the width of the film thickness non-uniform region existing at the edge of the pattern, As a result, there is an effect that patterning with higher definition becomes possible.
[0085]
As the dry etching method used in this embodiment, it is preferable that the dry etching is reactive ion etching. By using reactive ion etching, the organic film undergoes a chemical reaction and becomes a compound having a low molecular weight, so that it can be vaporized and evaporated to be removed from the substrate. This is because processing becomes possible.
[0086]
In this embodiment, it is preferable to use oxygen alone or a gas containing oxygen in the dry etching. By using oxygen alone or a gas containing oxygen, the organic film can be decomposed and removed by oxidation reaction, unnecessary organic substances can be removed from the substrate, and processing with high etching accuracy and short time is possible. . Further, under this condition, the normally used oxide transparent conductive film such as ITO is not etched, and therefore, it is effective in that the electrode surface can be purified without impairing the electrode characteristics.
[0087]
Furthermore, in this embodiment, it is preferable to use atmospheric pressure plasma for the dry etching. By using atmospheric pressure plasma, dry etching, which normally requires a vacuum apparatus, can be performed under atmospheric pressure, and the processing time and cost can be reduced. In this case, the etching can utilize the fact that the organic substance is oxidatively decomposed by oxygen in the atmosphere converted into plasma, but the gas composition of the reaction atmosphere may be arbitrarily adjusted by gas replacement and circulation.
[0088]
4). Photoresist layer peeling process
In this embodiment, after performing the light emitting layer developing step, a step of peeling the developed primary photoresist layer may be performed. Specifically, as shown in FIGS. 2 (b) to 2 (c), the primary photoresist layer remaining on the substrate is peeled to expose the light emitting portion, and then a secondary photoresist layer described later. It is a method of performing a formation process.
[0089]
In the state where the primary photoresist layer remains, it is difficult to form a secondary photoresist layer by laminating it, or by laminating the photoresist layer, the film thickness increases, and the subsequent light emitting layer In the case where a problem arises in the formation of the second photoresist layer, it is preferable to form the secondary photoresist layer from the state where all the photoresist layers on the substrate have been once peeled.
(Photoresist stripper)
When stripping such a photoresist layer, a photoresist stripping solution is used. The photoresist stripping solution that can be used in this embodiment does not dissolve the light emitting layer, but it is necessary to dissolve the photoresist layer, and the photoresist solvent as described above is used as it is. Can do. In addition, when a positive photoresist is used, it can be peeled off using the solution mentioned as the resist developer after UV exposure.
[0090]
Further, a strong alkaline aqueous solution, a solvent such as dimethylformamide, dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, a mixture thereof, or a commercially available resist stripping solution may be used. After the resist is peeled off, it may be rinsed with 2-propanol or the like and further rinsed with water.
[0091]
5). Secondary photoresist layer formation process
After performing the light emitting layer developing step, a step of forming a secondary photoresist layer on the substrate so as to cover the light emitting portion is performed.
[0092]
Since the secondary photoresist layer used here can be made of the same material as the primary photoresist layer, description thereof is omitted here.
[0093]
In this embodiment, the primary photoresist layer and the secondary photoresist layer may use the same photoresist or may use different photoresists. When performing the above-described photoresist layer peeling step, the primary photoresist and the secondary photoresist are used separately, and therefore it is preferable to use the same photoresist for reasons such as simple process.
[0094]
On the other hand, when the photoresist layer peeling step is not performed, it is necessary to form a secondary photoresist layer on the primary photoresist layer. Therefore, a different photoresist may be used depending on circumstances.
[0095]
6). Secondary photoresist layer development process
At the stage of FIGS. 1 (b) and 2 (b), the patterned light emitting portion end a was not covered with the primary photoresist layer and was exposed. When the next light emitting layer coating solution is further applied from this state, the light emitting layer material is eluted from the ends a and b into the applied light emitting layer coating solution, resulting in problems such as color mixing and pixel thinning. Occurs.
[0096]
In order to solve this problem, in the exposure / development process of the secondary photoresist layer, patterning is performed so as to cover the light emitting part with a width larger than the width of the primary photoresist layer left in the exposure / development process of the primary photoresist. Is made. That is, the secondary photoresist layer is exposed and developed with a size that covers the end of the light emitting portion and does not cover the adjacent light emitting portion.
[0097]
Since the other points are the same as those in the primary photoresist layer developing step, description thereof is omitted here.
7). Other
In this embodiment, after repeating the steps 1 to 6 twice, as described in the example of FIG. 1, the light emitting layer forming step and the photoresist layer forming step are performed again, and the formed photoresist layer After performing the exposure / development process and the development process of the formed light-emitting layer, a light-emitting portion of three colors can be formed by performing a photoresist layer peeling process.
[0098]
Then, after forming a 2nd electrode layer and a protective layer, it can be set as an EL element by sealing.
[0099]
B. Second embodiment
Next, a second embodiment of the EL device manufacturing method of the present invention will be described.
[0100]
In this embodiment, an EL element in which a plurality of types of light-emitting portions are formed on the substrate by patterning a plurality of types of light-emitting layers a plurality of times on the substrate on which the electrode layer is formed using a photolithography method. It is a manufacturing method and has at least the following steps.
(1) A step of forming a light emitting layer and a photoresist layer in this order on the substrate (light emitting layer and primary photoresist layer forming step)
(2) Step of developing after pattern exposure so that a portion of the photoresist layer corresponding to all light emitting portions remains on the photoresist layer (primary photoresist layer developing step)
(3) A step of forming a light emitting portion whose surface is covered with a photoresist layer by removing the exposed light emitting layer after removing the photoresist layer (light emitting layer developing step 1)
(4) Step of forming a photoresist layer on the substrate so as to cover the light emitting portion (secondary photoresist layer forming step)
(5) Step of developing the photoresist layer after pattern exposure so that the predetermined light emitting portion and its end are not exposed (secondary photoresist layer developing step)
(6) Step of removing the light emitting portion exposed by removing the photoresist layer (light emitting portion developing step 2)
First, the formation of the first light emitting part (FIGS. 3A to 3F) will be briefly described with reference to the first example shown in FIG.
[0101]
FIG. 3 shows a first example of this embodiment. As shown in FIG. 3A, the first light emitting layer 4 and the primary photoresist layer 5 are formed on the substrate 1 on which the electrode layer 2 and the buffer layer 3 are formed, similarly to the case shown in FIG. Light emitting layer and primary photoresist layer forming step).
[0102]
Next, the primary photoresist layer is exposed and developed (primary photoresist layer developing step). This embodiment is greatly different from the first embodiment, in this primary photoresist layer development step, in this embodiment, in this embodiment, the primary photoresist layer remains in the region where all the light emitting portions are formed. A photomask 6 is formed (FIG. 3A), and after being exposed by such a photomask 6, development is performed.
[0103]
Then, a process of developing the exposed first light emitting layer 4 is performed in a state where the primary photoresist layer 5 remains in a region where all the light emitting parts are formed (light emitting layer developing process 1, FIG. 3B). .
[0104]
Next, a secondary photoresist layer is formed so as to cover the light emitting portion on the substrate (secondary photoresist layer forming step, FIG. 3C).
[0105]
Then, only a predetermined light emitting portion is subjected to pattern exposure using a secondary photomass 6 ′ formed wider than the primary photomask 6 (FIG. 3D) and developed (secondary photoresist layer developing step, FIG. 3 (e)).
[0106]
Finally, by developing the light emitting layer remaining on the other light emitting portion, the secondary photoresist layer 5 ′ is formed on the first light emitting portion 4 ′ so that the end a is not exposed. (Light-emitting layer developing step 2, FIG. 3 (f)).
[0107]
Also in this embodiment, when patterning one light emitting layer, by performing the photoresist development process twice of the primary photoresist layer and the secondary photoresist layer, the end a of the first light emitting portion 4 ′ is formed. In the state of being coated with the photoresist layer, the next coating process of the second light emitting layer coating solution can be performed. Therefore, even if the next coating solution for the second light emitting layer is applied, problems such as color mixing do not occur.
[0108]
In addition, the feature of this embodiment is that the secondary photoresist layer is developed in a state where the buffer layer 3 is covered with the first light emitting layer 4 in the secondary photoresist layer developing step. That is, after the pattern exposure in FIG. 3 (d), the secondary photoresist layer is developed. At this time, the first light emitting layer 4 is present on the buffer layer (FIG. 3 (e)), and directly The photoresist layer developer does not come into contact with the buffer layer. Therefore, this embodiment has an advantage that even a buffer layer made of a material soluble in a photoresist developer can be used.
[0109]
FIG. 4 shows the process up to the formation of the first light emitting section in the second example of the present embodiment (FIGS. 4A to 4F). In this example, the process up to the step of FIG. 3B, that is, the step of developing the primary photoresist layer 5 and developing the first light emitting layer (light emitting layer developing step 1) is exactly the same (FIG. 4B). Next, it is characterized in that a step of peeling the developed primary photoresist layer 5 is performed (primary resist peeling step, see FIG. 4C).
[0110]
Next, a secondary photoresist layer 5 ′ is formed on the entire surface of the substrate from which the first photoresist layer 4 ′ is exposed and the first light emitting portion 4 ′ is exposed. The photoresist layer 5 ′ is formed wide using a secondary photomask 6 ′ and is covered with the secondary photoresist layer 5 ′ so that the end a of the first light emitting portion 4 ′ is not exposed ( FIG. 4 (f)).
[0111]
In the second method, it is necessary to carry out an extra step called a photoresist layer peeling step between the light emitting layer developing step 1 and the secondary photoresist layer forming step, but it has already been formed as in the example shown in FIG. Since the photoresist layer is not formed again on the photoresist layer, the formation of the secondary photoresist layer is easy, and the film thickness does not increase significantly. It has the advantage that it can be formed.
[0112]
Also in the second method, when the primary photoresist layer is developed as in the first method (FIG. 4D), the light emitting layer 4 is present (FIG. 4E), so that the buffer layer 3 does not come into direct contact with the photoresist developer. Therefore, there is an advantage that even a buffer layer soluble in a photoresist developer can be used.
[0113]
Also in this embodiment, as in the case of the first embodiment, the same process is performed on the second light emitting layer (FIG. 3 (g) to FIG. 3 (k)), whereby the first light emitting section 4 ′. The coating solution for the third light emitting layer can be applied in a state where the end portion a of the first light emitting portion 8 and the end portion b of the second light emitting portion 8 ′ are covered (FIG. 3 (l)), and color mixing can be prevented. . Similarly to the first light emitting portion forming step, the second light emitting layer 8 exists on the buffer layer during the secondary photolithography layer developing step (FIG. 3 (j)), and then the light emitting layer developing step. 2 is performed (FIG. 3 (k)). Therefore, the buffer layer 3 does not come into direct contact with the photoresist developer even when the second light emitting portion is formed.
[0114]
In the second example of the present embodiment, the same process can be performed on the second light emitting layer in the same manner (FIGS. 4G to 4K).
[0115]
Then, after forming the third light emitting layer and the photoresist layer, exposure (FIG. 3 (l) and FIG. 4 (l)) and development are performed, so that the first light emitting unit 4 ′, the second light emitting unit 8 ′, A third light emitting unit 9 ′ is formed. Finally, a second electrode layer is formed on these light emitting portions, and an EL element that emits EL light is produced below the figure.
[0116]
Hereafter, each process of the manufacturing method of such an EL element of this embodiment is demonstrated in detail. Note that the materials used in the present embodiment and the method for forming the same are the same as those described in the first embodiment, except for the points particularly pointed out in the following description. Is omitted.
[0117]
1. Light emitting layer and primary photoresist layer forming process
In this embodiment, as in the first embodiment, first, a light emitting layer and primary photoresist layer forming step for forming a light emitting layer and a photoresist layer in this order on a substrate is performed.
[0118]
In this embodiment, as will be described later, an organic EL layer soluble in a photoresist developer, such as a buffer layer, can be formed on the electrode layer. Such a buffer layer will be described.
[0119]
(Buffer layer)
The buffer layer in the present embodiment is provided between the anode and the light emitting layer or between the cathode and the light emitting layer so that charge can be easily injected into the light emitting layer, and is an organic substance, particularly an organic conductor, etc. It is a layer containing. For example, it is possible to increase the efficiency of hole injection into the light-emitting layer and to form a conductive polymer having a function of flattening irregularities such as electrodes.
[0120]
When the conductivity of the buffer layer used in this embodiment is high, it is desirable that the buffer layer be patterned in order to maintain the diode characteristics of the device and prevent crosstalk. If the resistance of the buffer layer is high, the patterning may not be necessary. In the case of an element that can omit the buffer layer, the buffer layer may not be provided.
[0121]
In this embodiment, when both the buffer layer and the light emitting layer are formed by patterning by photolithography, the material forming the buffer layer is insoluble in the photoresist solvent and the solvent used for forming the light emitting layer. It is preferable to select, and more preferably, the material for forming the buffer layer is a material that is insoluble in the photoresist stripping solution.
[0122]
Specific examples of the material for forming the buffer layer used in this embodiment include polyalkylthiophene derivatives, polyaniline derivatives, polymers of hole transporting substances such as triphenylamine, sol-gel films of inorganic oxides, trifluoromethane Examples include organic polymer films such as Lewis acid-containing organic compound films, etc., but are not particularly limited as long as the above-described solubility conditions are satisfied. The condition may be satisfied.
[0123]
In addition, the solvent used in forming the buffer layer in the present embodiment is not particularly limited as long as the buffer material is dispersed or dissolved. When a film is required, it is necessary to use a buffer layer solvent that does not dissolve the photoresist material, and more preferably a buffer layer solvent that does not dissolve the light emitting layer.
[0124]
As the buffer layer solvent that can be used in this embodiment, a solvent having a resist material solubility of 0.001 (g / g solvent) or less at 25 ° C. and 1 atm is selected.
It is preferable to select a solvent of 0.0001 (g / g solvent) or less. Further, it is more preferable to select a solvent having a solubility of the light-emitting layer constituting material of 0.001 (g / g solvent) or less at 25 ° C. and 1 atm, particularly 0.0001 (g / g) as the buffer layer solvent. Solvent) The following solvents are preferably selected.
[0125]
Specific examples include water, methanol, ethanol and other alcohols, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone, and other solvents that satisfy the conditions. Can be used. Two or more solvents may be mixed and used.
[0126]
2. Primary photoresist layer development process
Next, a primary photoresist layer developing step is performed in which the photoresist layer is subjected to pattern exposure and developed so that a portion of the photoresist layer corresponding to all light emitting portions remains on the formed photoresist layer.
[0127]
This step is significantly different from the first embodiment, and the first embodiment is performed so that the portion of the photoresist layer corresponding to the portion corresponding to the predetermined light emitting portion remains. Then, pattern exposure is performed and developed so that portions of the photoresist layer corresponding to all the light emitting portions remain.
[0128]
3. Light emitting layer development process 1
Then, as described above, the light emitting layer developing process 1 is performed in which the light emitting layer whose surface is covered with the photoresist layer is formed by removing the exposed light emitting layer by removing the photoresist layer.
[0129]
In this way, after the primary photoresist layer forming step is performed, the light emitting layer existing between the portions corresponding to the light emitting portions covered with the primary photoresist layer is removed by performing the light emitting layer developing step 1. Can do.
[0130]
In the above step 2 and this step, the end of the light emitting part is removed in the next step by removing the light emitting layer existing between the light emitting part, that is, the part where the buffer layer is present, while removing the light emitting layer existing therebetween. At the same time as covering the secondary photoresist layer to be formed, the buffer layer can be protected by the light emitting layer in the subsequent development step of the secondary photoresist layer.
[0131]
4). Photoresist layer peeling process
In this embodiment, as in the first embodiment, after the light emitting layer developing step is performed, a step of peeling the developed primary photoresist layer may be performed. In the state where the primary photoresist layer remains, it is difficult to form a secondary photoresist layer by laminating it, or by laminating the photoresist layer, the film thickness increases, and the subsequent light emitting layer In the case where a problem arises in the formation of the second photoresist layer, it is preferable to form the secondary photoresist layer from the state where all the photoresist layers on the substrate have been once peeled.
[0132]
5). Secondary photoresist layer formation process
Next, a secondary photoresist layer forming step of forming a photoresist layer on the substrate so as to cover the light emitting portion is performed. Thereby, as described above, the light emitting portion end is covered with the secondary photoresist layer.
[0133]
6). Secondary photoresist layer development process
Then, a secondary photoresist layer developing step is performed in which the photoresist layer is subjected to pattern exposure and then developed so that a predetermined light emitting portion and its end portion are not exposed. In this step, when developing the secondary photoresist layer, the buffer layer located on the electrode layer, that is, in the region where the light emitting portion is formed is covered with the light emitting layer. There is no contact with the photoresist layer developer used in the layer development step. Therefore, in the present embodiment, it is possible to use a buffer layer that is soluble in the photoresist layer developer as described above.
[0134]
7). Light emitting layer development process 2
Next, a light emitting portion developing process 2 is performed in which the light emitting portion exposed by removing the photoresist layer is removed.
[0135]
In this embodiment, the light emitting layer developing step is performed in two steps in this manner, so that the buffer layer is covered with the light emitting layer and not exposed in the photoresist layer developing step.
[0136]
In this embodiment, as compared with the first embodiment, the light emitting layer developing process is certainly performed once more. However, in some cases, a buffer layer soluble in a solvent must be formed in order to improve luminous efficiency, and this embodiment can be said to be a useful embodiment in such a case.
[0137]
The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.
[0138]
【Example】
The following examples further illustrate the invention.
[0139]
[Example]
(Buffer layer deposition)
A patterned ITO substrate having a size of 6 inches and a thickness of 1.1 mm was washed to obtain a substrate and a first electrode layer. A buffer layer coating solution (manufactured by Bayer; BaytronP, represented by the following chemical formula (1)) was dropped onto the center of the substrate to perform spin coating. The layer was formed by holding at 2500 rpm for 20 seconds. As a result, the film thickness was 800 angstroms.
[0140]
[Chemical 1]

[0141]
2 ml of a positive photoresist solution (manufactured by Tokyo Ohka Kogyo Co., Ltd .; OFPR-800) was taken and dropped onto the center of the substrate for spin coating. The layer was formed by holding at 500 rpm for 10 seconds and then holding at 2000 rpm for 20 seconds. As a result, the film thickness was about 1 μm. Pre-baking was performed at 80 ° C. for 30 minutes. Then, it set with the exposure mask to the alignment exposure machine, and ultraviolet-exposed to the part which wants to remove a buffer layer. After developing with a resist developer (manufactured by Tokyo Ohka Co., Ltd .; NMD-3) for 20 seconds, it was washed with water to remove the photoresist layer and the buffer layer in the exposed area. After post-baking at 120 ° C. for 30 minutes, the photoresist layer was completely removed with acetone, and a buffer layer insoluble in acetone was formed into an arbitrary pattern.
[0142]
(Light-emitting layer deposition)
2 ml of 1 wt% xylene solution of polyparaphenylene vinylene derivative light emitting polymer MEH-PPV (shown in the following chemical formula (2)) is taken on a substrate having a buffer layer patterned as a first light emitting layer, It was dripped at the center and spin coating was performed. The layer was formed by holding at 2000 rpm for 10 seconds. As a result, the film thickness was 800 angstroms.
[0143]
[Chemical formula 2]

[0144]
2 ml of a positive photoresist solution (manufactured by Tokyo Ohka Kogyo Co., Ltd .; OFPR-800) was taken and dropped onto the center of the substrate for spin coating. The layer was formed by holding at 500 rpm for 10 seconds and then holding at 2000 rpm for 20 seconds. As a result, the film thickness was about 1 μm. Pre-baking was performed at 80 ° C. for 30 minutes. Then, it set to the alignment exposure machine with the exposure mask, and exposed the ultraviolet-ray to the part which wants to remove light emitting layers other than a 1st light emission part. After developing with a resist developer (manufactured by Tokyo Ohka Co., Ltd .; NMD-3) for 20 seconds, it was washed with water to remove the exposed photoresist layer. After post-baking at 120 ° C. for 30 minutes, the light emitting layer where the photoresist layer was removed was removed with toluene. After removing the photoresist with acetone, 2 ml of a positive photoresist solution (manufactured by Tokyo Ohka Kogyo Co., Ltd .; OFPR-800) was again taken and dropped onto the center of the substrate to perform spin coating. The layer was formed by holding at 500 rpm for 10 seconds and then holding at 2000 rpm for 20 seconds. As a result, the film thickness was about 1 μm. Pre-baking was performed at 80 ° C. for 30 minutes. Then, it set to the alignment exposure machine with the exposure mask, and exposed to ultraviolet rays so as to leave a photoresist layer having a width 10 μm larger than the width of the first light emitting portion. After developing with a resist developer (manufactured by Tokyo Ohka Co., Ltd .; NMD-3) for 20 seconds, it was washed with water to remove the exposed photoresist layer. Post-baking was performed at 120 ° C. for 30 minutes to obtain a substrate in which the first light emitting portion was protected with a photoresist layer having a width 10 μm larger than the width of the first light emitting portion.
[0145]
As the second light emitting layer, 2 ml of 1 wt% xylene solution of polyparaphenylene vinylene derivative light emitting polymer MEH-PPV was taken and dropped on the center of the substrate to perform spin coating. The layer was formed by holding at 2000 rpm for 10 seconds. As a result, the film thickness was 800 angstroms.
[0146]
2 ml of a positive photoresist solution (manufactured by Tokyo Ohka Kogyo Co., Ltd .; OFPR-800) was taken and dropped onto the center of the substrate for spin coating. The layer was formed by holding at 500 rpm for 10 seconds and then holding at 2000 rpm for 20 seconds. As a result, the film thickness was about 1 μm. Pre-baking was performed at 80 ° C. for 30 minutes. Then, it set to the alignment exposure machine with the exposure mask, and exposed the ultraviolet-ray to the part which wants to remove light emitting layers other than a 1st light emission part and a 2nd light emission part. After developing with a resist developer (manufactured by Tokyo Ohka Co., Ltd .; NMD-3) for 20 seconds, it was washed with water to remove the photoresist in the exposed area. After post-baking at 120 ° C. for 30 minutes, the light emitting layer where the photoresist was removed with toluene was removed. After removing the photoresist with acetone, 2 ml of a positive photoresist solution (OFPR-800 manufactured by Tokyo Ohka Kogyo Co., Ltd.) was again taken and dropped onto the center of the substrate to perform spin coating. The layer was formed by holding at 500 rpm for 10 seconds and then holding at 2000 rpm for 20 seconds. As a result, the film thickness was about 1 μm. Pre-baking was performed at 80 ° C. for 30 minutes. Then, it set to the alignment exposure machine with the exposure mask, and ultraviolet-ray-exposed so that a photoresist layer might remain in the width | variety 10 micrometer larger than the width | variety of a 1st light emission part and a 2nd light emission part. After developing with a resist developer (manufactured by Tokyo Ohka Co., Ltd .; NMD-3) for 20 seconds, it was washed with water to remove the photoresist in the exposed area. Post baking was performed at 120 ° C. for 30 minutes to obtain a substrate protected with a photoresist having a width 10 μm larger than the width of the first light emitting portion and the second light emitting portion.
[0147]
As a third light emitting layer, 2 ml of 1 wt% xylene solution of polyparaphenylene vinylene derivative light emitting polymer MEH-PPV was taken and dropped on the center of the substrate to perform spin coating. The layer was formed by holding at 2000 rpm for 10 seconds. As a result, the film thickness was 800 angstroms.
[0148]
2 ml of a positive photoresist solution (manufactured by Tokyo Ohka Kogyo Co., Ltd .; OFPR-800) was taken and dropped onto the center of the substrate for spin coating. The layer was formed by holding at 500 rpm for 10 seconds and then holding at 2000 rpm for 20 seconds. As a result, the film thickness was about 1 μm. Pre-baking was performed at 80 ° C. for 30 minutes. Then, it set to the alignment exposure machine with the exposure mask, and exposed the ultraviolet-ray to the part which wants to remove light emitting layers other than a 1st light emission part, a 2nd light emission part, and a 3rd light emission part. After developing with a resist developer (manufactured by Tokyo Ohka Co., Ltd .; NMD-3) for 20 seconds, it was washed with water to remove the photoresist in the exposed area. After post-baking at 120 ° C. for 30 minutes, the light emitting layer where the photoresist has been removed with toluene is removed, and the first light emitting unit, the second light emitting unit, and the third light emitting unit are protected with a photoresist. Obtained. Thereafter, all of the photoresist was removed with acetone to expose the patterned light emitting layer.
After drying at 100 ° C. for 1 hour, Ca was deposited as a second electrode layer (upper electrode) with a thickness of 500 Å on the obtained substrate, and Ag was further deposited as a protective layer with a thickness of 2500 Å. An EL element was produced.
[0149]
(Evaluation of light emission characteristics of EL element)
The ITO electrode side was connected to the positive electrode, the Ag electrode side was connected to the negative electrode, and a direct current was applied by a source meter. Light emission was recognized from each of the first light-emitting part, the second light-emitting part, and the third light-emitting part when 10 V was applied.
[0150]
[Comparative example]
Example, except that after the development process of the first light emitting layer and the second light emitting layer, the photoresist layer was peeled off and the secondary photoresist layer was formed, exposed, and re-protected by the development process. An EL element was produced in the same manner as in 1. During the development of the second light emitting layer and the third light emitting layer, the already patterned light emitting layer was eluted, resulting in pixel thinning.
[0151]
【The invention's effect】
According to the present invention, since the patterned light emitting portion is covered with the photoresist layer so as not to be exposed, the already formed light emitting portion is not in contact with the light emitting layer coating liquid to be applied later. There is an effect that it is possible to prevent color mixture and pixel thinning caused by contact with the coating liquid for use.
[Brief description of the drawings]
FIG. 1 is a process diagram showing a first example of a first embodiment in a method for producing an EL element of the present invention.
FIG. 2 is a process diagram showing a second example of the first embodiment in the method for producing an EL element of the present invention.
FIG. 3 is a process diagram showing a first example of a second embodiment in the method for manufacturing an EL element of the present invention.
FIG. 4 is a process diagram showing a second example of the second embodiment in the method for manufacturing an EL element of the present invention.
FIG. 5 is a process diagram showing a conventional method of manufacturing an EL element.
[Explanation of symbols]
1 ... Base
2… Electrode layer
3 ... Buffer layer
4 ... 1st light emitting layer
4 '... 1st light emission part
5 ... Primary photoresist layer
5 '... Secondary photoresist layer
8 ... 2nd light emitting layer
8 '... 2nd light emission part
9: Third light emitting layer
9 '... 3rd light emission part
a: End of first light emitting unit
b: End of second light emitting unit

Claims (5)

A method for manufacturing an electroluminescent element, wherein a plurality of types of light emitting portions are formed on the substrate by patterning a plurality of types of light emitting layers a plurality of times on the substrate on which the electrode layer is formed using a photolithography method. In
Forming a light emitting layer and a primary photoresist layer in this order on the substrate;
Relative to the primary photoresist layer, as a primary photoresist layer in a portion corresponding to a predetermined light emitting portion is left, after the pattern exposure, a step of developing,
By removing the light emitting layer in which the primary photoresist layer is exposed by removing the primary photoresist layer by covered with the light emitting portion surface and the exposed light emitting end surface which is not covered with the primary photoresist layer Forming a step;
Forming a secondary photoresist layer so as to cover the light emitting portion surface and the light emitting end surface ;
Developing the secondary photoresist layer after pattern exposure so that the light emitting portion surface and the light emitting end surface are not exposed; and
A method for producing an electroluminescent device, comprising: A method of manufacturing an electroluminescent element, wherein a plurality of types of light emitting portions are formed on a substrate by patterning a plurality of types of light emitting layers on the substrate on which the electrode layer is formed, using a photolithography method a plurality of times. In
  Forming a light emitting layer and a primary photoresist layer in this order on the substrate;
  A step of developing after pattern exposure so that a portion of the primary photoresist layer corresponding to a predetermined light emitting portion remains with respect to the primary photoresist layer; and
  By removing the light emitting layer exposed by removing the primary photoresist layer, the light emitting portion surface covered by the primary photoresist layer and the exposed light emitting end surface not covered by the primary photoresist layer are formed. Forming, and
  Peeling the primary photoresist layer remaining on the light emitting part to expose the light emitting part;
  Forming a secondary photoresist layer on the substrate on which the exposed light emitting part is formed so as to cover the light emitting part;
  Developing the secondary photoresist layer after pattern exposure so that the light emitting portion surface and the light emitting end surface are not exposed; and
A method for producing an electroluminescent device, comprising: A method for manufacturing an electroluminescent element, wherein a plurality of types of light emitting portions are formed on the substrate by patterning a plurality of types of light emitting layers a plurality of times on the substrate on which the electrode layer is formed using a photolithography method. In
Forming a light emitting layer and a primary photoresist layer in this order on the substrate;
Relative to the primary photoresist layer, so that the primary photoresist layer portion corresponding to all the light-emitting portion remaining after pattern exposure, a step of developing,
By removing the light emitting layer in which the primary photoresist layer is exposed by removing the primary photoresist layer by covered with the light emitting portion surface and the exposed light emitting end surface which is not covered with the primary photoresist layer Forming a step;
Forming a secondary photoresist layer so as to cover the light emitting portion surface and the light emitting end surface ;
A primary photoresist layer and a secondary photoresist other than the predetermined light emitting portion are developed by pattern exposure of the secondary photoresist layer so that the predetermined light emitting portion surface and the predetermined light emitting end surface are not exposed. and the more engineering to remove the layers,
Removing the light emitting part exposed by removing the primary photoresist layer and the secondary photoresist layer; and
A method for producing an electroluminescent device, comprising: A method of manufacturing an electroluminescent element, wherein a plurality of types of light emitting portions are formed on a substrate by patterning a plurality of types of light emitting layers on the substrate on which the electrode layer is formed, using a photolithography method a plurality of times. In
  Forming a light emitting layer and a primary photoresist layer in this order on the substrate;
  A step of developing after pattern exposure so that a portion of the primary photoresist layer corresponding to all light emitting portions remains with respect to the primary photoresist layer, and developing.
  By removing the exposed light emitting layer after removing the primary photoresist layer, the light emitting portion surface covered with the primary photoresist layer and the exposed light emitting end surface not covered with the primary photoresist layer are formed. Forming, and
  Peeling the primary photoresist layer remaining on all of the light emitting parts to expose all of the light emitting parts;
  Forming a secondary photoresist layer on the substrate on which the exposed light emitting part is formed so as to cover the light emitting part;
  A step of removing the secondary photoresist layer other than the predetermined light emitting portion by pattern exposure of the secondary photoresist layer and developing so that the predetermined light emitting portion surface and the predetermined light emitting end surface are not exposed. When,
  Removing the light emitting portion exposed by removing the secondary photoresist layer;
A method for producing an electroluminescent device, comprising:   5. The method according to claim 1, wherein the step of removing the light emitting layer or the light emitting portion exposed by removing the photoresist layer is a step of removing by dry etching. The manufacturing method of the electroluminescent element of description.

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