JP2005203345A - Substrate for organic el panel, organic el panel, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent occurrence of faults such as leakage resulting from the remainder of a removal resist film. <P>SOLUTION: This is a manufacturing method of an organic EL panel in which an organic EL element wherein an organic material layer containing an organic luminous layer is interposed between an lower electrode and an upper electrode is formed on a support substrate 1 and a wiring electrode extended from the lower electrode and the upper electrode is formed. When a wiring pattern portion is formed on the conductive film layers 10A, 10B forming the above wiring electrode according to a pattern of a resist film 11 to be formed after the exposed portion is removed, a first exposure is applied on the resist film 11 through a photo mask 20 having a light shield part 20A corresponding to the wiring pattern portion, and then, a second exposure is applied on the removal objective portion of the resist film 11 corresponding to at least the light-emitting part of the organic EL element. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an organic EL (Electroluminescence) panel, a substrate for the panel, and a manufacturing method thereof.

  The organic EL panel has a basic structure of an organic EL element in which a lower electrode is formed on a support substrate, an organic material layer including a light emitting layer made of an organic compound is formed thereon, and an upper electrode is formed thereon. The organic EL element is formed on a support substrate as a unit surface light emitting element.

  In addition, in order to connect the drive circuit to the organic EL panel, wiring electrodes extending from the lower electrode and the upper electrode are formed on a support substrate. An extraction electrode is formed by being drawn out from a sealing portion that seals the element.

  In forming such an organic EL panel, first, a wiring pattern of a lower electrode and a wiring electrode is formed on a support substrate, and other components of the organic EL element are formed on the panel substrate on which the wiring pattern is formed. It will be formed sequentially. In general, the wiring electrode forming the extraction electrode portion is formed of a laminate of conductive films such as metal films, and attempts have been made to reduce the electrical resistance as much as possible.

  In the prior art described in Patent Document 1 below, a transparent conductive film for forming a lower electrode is formed on a support substrate made of a glass substrate, and then a metal is used for a necessary wiring electrode formation portion using a shadow mask. A film substrate is formed to obtain a panel substrate on which a resist film pattern is formed in accordance with the positions of the lower electrode and the wiring electrode. And it is disclosed that the lower electrode and the wiring electrode are patterned by etching the metal film and the transparent conductive film on the panel substrate.

  In general, a conductive film for forming a lower electrode is formed on a support substrate, and a conductive film such as a metal film for forming a wiring pattern portion of the wiring electrode is formed on the conductive film. A panel substrate on which a resist film pattern corresponding to the pattern portion is formed is obtained, and then a wiring pattern portion made of a conductive film such as a metal film is formed by edging performed on the panel substrate. An electrode pattern is formed.

JP 2003-163080 A

  In such a conventional technique, a photolithography technique using a positive resist is employed when forming a pattern of a lower electrode or a wiring electrode formed on a support substrate. That is, the resist film applied on the conductive film layer is exposed with ultraviolet light or the like through a photomask having a light-shielding portion corresponding to the pattern to be formed, and the exposed resist film is removed by development processing. Thus, a panel substrate in which a pattern by a resist film is formed on an unexposed portion is obtained. Thereafter, the conductive film exposed from the resist film on the panel substrate is removed by etching to form a wiring pattern on the support substrate. Here, the panel substrate refers to the substrate in a state where the conductive layer of the lower electrode and the wiring electrode is formed on the support substrate and before the wiring pattern portion is formed by etching.

  A problem with such a panel substrate or an organic EL panel using the panel substrate is when a resist film that should have been removed by exposure remains partially. If dust or the like adheres to the photomask and the exposure of the portion to be removed of the resist film becomes insufficient, the resist film remains in that portion, and the conductive film that should be removed by the subsequent etching remains partially. Things happen. If this is on the lower electrode corresponding to the light emitting portion of the organic EL element, a local conductive film protrusion is formed on the lower electrode on which the organic material layer is formed. When an organic material layer is formed thereon and an upper electrode is further formed thereon, a local thin layer portion of the organic material layer is formed between the upper and lower electrodes in the light emitting portion of the organic EL element. Therefore, there arises a problem that problems such as leakage occur.

  In particular, the occurrence of leaks is an important problem for organic EL panels. If there is a current in the reverse direction (leakage current), crosstalk, uneven brightness, or dot defects occur, which is fatal as a mass-produced product. It can be bad. In addition, when a local thin layer portion of the organic material layer is formed as described above, a leak current is generated by a reverse bias voltage applied during operation even if no defect is confirmed during manufacturing. In some cases, problems such as expansion of non-lighting areas and increase in power consumption with the passage of operating time occur after product shipment.

  One object of the present invention is to deal with such a problem. That is, an organic EL element in which an organic material layer including an organic light emitting layer is sandwiched between a lower electrode and an upper electrode is formed on a support substrate, and a wiring electrode extending from the lower electrode and the upper electrode is formed. In the organic EL panel substrate, the organic EL panel, and the manufacturing method thereof, it is an object of the present invention to prevent the occurrence of problems such as leakage due to the remaining resist film.

  In order to achieve such an object, a substrate for an organic EL panel, an organic EL panel, and a method for manufacturing an organic EL panel according to the present invention include at least the configurations according to the following independent claims.

[Claim 1] An organic EL element in which an organic material layer including an organic light emitting layer is sandwiched between a lower electrode and an upper electrode is formed on a support substrate, and wiring extended from the lower electrode and the upper electrode An organic EL panel substrate for forming an electrode,
When forming the wiring pattern portion according to the pattern of the resist film formed by removing the exposed portion on the conductive film layer forming the wiring electrode,
An organic EL panel substrate, wherein an exposure process is performed a plurality of times on at least a part of the removal target portion of the resist film.

[Claim 5] An organic EL element in which an organic material layer including an organic light emitting layer is sandwiched between a lower electrode and an upper electrode is formed on a support substrate, and wiring extended from the lower electrode and the upper electrode An organic EL panel manufacturing method for forming an electrode,
When forming the wiring pattern portion according to the pattern of the resist film formed by removing the exposed portion on the conductive film layer forming the wiring electrode,
A first exposure step of exposing a portion to be removed of the resist film formed on the conductive film layer;
And a second exposure step of exposing at least a part of the removal target portion of the resist film corresponding to the light emitting portion of the organic EL element.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an example of the structure of an organic EL panel targeted in the present invention. Here, an example in which the passive drive method is adopted is shown, but the embodiment of the present invention is not limited to this. 4A is an overall perspective view, FIG. 2B is an XX sectional view, and FIG. 2C is a YY sectional view. In this organic EL panel, an organic material layer 4 is sandwiched between a plurality of lower electrodes 2 formed in a stripe shape on a support substrate 1 and a plurality of upper electrodes 3 formed in a stripe shape in a direction perpendicular thereto. With this structure, an organic EL element is formed at the intersection of the lower electrode 2 and the upper electrode 3. Each layer of the organic material layer 4 forming the organic EL element includes, for example, a hole transport layer 4a, a light emitting layer 4b, and an electron transport layer 4c. In FIG. 2B, L ₀ indicates a light emitting region of the organic EL panel, and L ₁ indicates a light emitting portion of the organic EL element.

Then, the wiring electrode 2A is formed by extending from the lower electrode 2, and the wiring electrodes 3A and 3B are formed by extending from the upper electrode 3, and these wiring electrodes 2A, 3A and 3B are not shown. An extraction electrode extracted from the stop is formed. In addition, a wiring pattern portion 5 is formed at an end portion where the lead electrodes of the wiring electrodes 2A, 3A, and 3B are formed. In the wiring pattern portion 5, the wiring electrodes 2A and 3B are formed of a laminated body of a plurality of conductive films. In the illustrated example, the wiring electrode 2A extending from the lower electrode 2 is the first conductive film. 2A ₁ and made from the second conductive film 2A ₂ Prefecture, similarly, the wiring electrodes 3B extending from the upper electrode 3 is made of a first conductive film 3B ₁ and the second conductive film 3B ₂ Prefecture. The wiring pattern portion 5 can be formed by etching after patterning by photolithography, but this etching may be performed simultaneously with the second conductive films 2A ₂ and 3B ₂ and the first conductive films 2A ₁ and 3B _1. However, they may be performed sequentially.

  As another structure, the lower electrode 2 is formed along the upper electrode 3 on the insulating film 6 that insulates and partitions the lower electrode 2 for each light emitting portion of the organic EL element, and the upper electrode 3 and the organic material layer 5 are formed. Is provided with a partition wall 7 for insulating partitioning.

In such an organic EL panel, the embodiment of the present invention is characterized by the panel substrate on which the pattern of the wiring pattern portion 5 is formed. FIG. 2 is an explanatory view for explaining the process of forming the panel substrate. First, conductive film layers 10 </ b> A and 10 </ b> B are formed on the support substrate 1. The conductive film layer 10A is for forming the first conductive films 2A ₁ , 3B ₁ or the lower electrode 2, and the conductive film layer 10B is for forming the second conductive films 2A ₂ , 3B ₂ . A positive resist film 11 is applied on the conductive film layer 10B, and a photomask 20 is disposed on the positive resist film 11 to perform exposure with ultraviolet rays or the like. The photomask 20 includes a light shielding portion 20A having a pattern corresponding to the wiring pattern portion 5 to be formed, and thereby the removal target portion 11a of the resist film 11 is exposed.

At this time, the removal target portion 11a of the resist film 11 forms the pattern of the second conductive films 2A ₂ and 3B _{2 in} the wiring pattern portion 5, but the light emitting region L ₀ of the organic EL panel is formed in other regions. All the regions including the region become the removal target portion 11a. Here, for example, the unexposed portion of the resist film 11 exists at a position corresponding to the light-emitting portion L ₁ of the organic EL element, is left resist film to be removed in the subsequent development process, resist further subsequent etching process Since the conductive film remains in the portion where the film is left, this causes product defects such as leakage.

Therefore, in the embodiment of the present invention, the removal target portion of the resist film 11 corresponding to the light emitting portion L ₁ of at least an organic EL element is subjected to multiple exposures. In this case, it is preferable to perform the multiple exposures by changing the installation state and type of the photomask 20 or changing the exposure conditions in order to avoid unexposed portions to be removed. Thereby, the unexposed portion of the removal target portion 11a of the resist film 11 can be eliminated, and problems such as leakage of the organic EL panel can be solved.

  After such exposure processing, the resist film pattern 11b is developed as shown in FIG. In the panel substrate in this state, a resist film pattern 11b corresponding to the wiring pattern portion 5 is formed on the conductive film layer 10B. When exposure is performed a plurality of times by changing the installation state and type of the photomask 20 or by changing the exposure conditions, there is a slight effect on the edge of the resist film pattern 11b, but there is a significant effect on the pattern itself. Does not occur.

The obtained Thereafter, as shown in FIG. (C), the exposed portions of the conductive layer 10B is etched, for example, a desired wiring pattern formed of the second conductive film 2A _2. Thereafter, the resist film is peeled off, and the conductive layer 10A is patterned as the next step. Here, the case where the conductive film layer 10A is etched after the conductive film layer 10B is etched is shown as an example. However, for the wiring pattern portion 5, the conductive film layers 10A and 10B can be etched simultaneously.

FIG. 3 is an explanatory diagram illustrating a method for manufacturing an organic EL panel according to an embodiment of the present invention. In the substrate preparation step (S1), the support substrate 1 is polished or cleaned. In the film forming step (S2), film formation for forming the conductive film layers 10A and 10B on the support substrate 1 is performed. In the resist coating step (S3), the resist film 11 is applied on the conductive film layer 10B. In the wiring pattern portion forming step (S4), as described above, a plurality of exposure steps including the first exposure step S41 and the second exposure step S42, the developing step (S43), the etching step (S44), and the resist peeling. Step (S45) is included. In the lower electrode formation step (S5), the lower electrode 2 is formed by patterning the conductive film layer 10A. In the insulating film, the partition wall formation step (S6), the insulating film 6 and the partition wall 7 so as to partition the light-emitting portion L ₁ of the organic EL element on the lower electrode 2 is formed. In the organic material layer forming step (S7), the organic material layer 5 is sequentially formed. In the upper electrode formation step (S8), the upper electrode 3 is formed on the organic material layer 5. In the sealing step (S9), attached to each other the sealing member to the support substrate, the light emitting region L ₀ of the organic EL panel is sealed.

  The wiring pattern portion forming step (S4) in such an organic EL panel will be described more specifically. As described above, the multiple exposures are preferably performed by changing the installation state and type of the photomask 20 or changing the exposure conditions. Unexposed portions of the resist film 11 to be removed are often caused by foreign matter or the like attached to the photomask 20, so that the unexposed portion does not occur if the foreign matter adheres to the resist film 11.

  Therefore, the first exposure process and the second exposure process can be repeated exposure processes using the photomask 20 for forming the wiring pattern portion 5, but in this case, exposure such as the light irradiation angle is performed. By changing the conditions, unexposed portions of the resist film 11 to be removed can be avoided.

  Further, the first exposure process and the second exposure process are repeated as an exposure process using the photomask 20 for forming the wiring pattern portion 5, and the photomask 20 is further replaced for each exposure process. As a result, it is considered that there is no overlapping of foreign matter and the like on the photomask 20 before and after the replacement, so that unexposed portions of the resist film 11 to be removed can be avoided.

  Further, the first exposure process and the second exposure process are repeated as an exposure process using the photomask 20 for forming the wiring pattern portion 5, and the photomask 20 is used as a single exposure process. By slightly shifting the arrangement every time (a minute distance that does not affect pattern formation), it is possible to avoid unexposed portions of the resist film 11 to be removed.

Further, it is also possible to use photomasks having different patterns as shown in FIG. 4 in the first exposure process and the second exposure process. That is, in the first step, as shown in FIG. 5A, the light shielding patterns 21a and 21b corresponding to the wiring pattern portion 5 (here, the wiring pattern portion 5 is formed in different directions) for each organic EL panel region 21A. However, it is a matter of course that the wiring pattern portion 5 may be formed in the same direction as shown in FIG. used in the second step, as shown in FIG. (b), a photomask 22 made for each organic EL panel region 22A, the light-shielding substrate formed with the exposure pattern 22a corresponding to the light-emitting region L ₀ of the organic EL panel Is used. This also, in part to the light emitting region L ₀ of at least an organic EL panel, since a plurality of exposures are made using different photomasks, it can be avoided unexposed resist film 11.

  The characteristics according to the embodiment of the present invention described above are summarized as follows.

For example, an organic EL element in which an organic material layer 4 including an organic light emitting layer is sandwiched between a lower electrode 2 and an upper electrode 3 is formed on a support substrate 1, and extends from the lower electrode 2 and the upper electrode 3. A method for manufacturing a substrate for an organic EL panel, an organic EL panel or an organic EL panel for forming the exposed wiring electrodes 2A and 3B, wherein the exposed portions are formed on the conductive layers 10A and 10B forming the wiring electrodes 3A and 3B. when forming the wiring pattern portion 5 in accordance with the pattern 11b of the resist film 11 which is formed by removing a part of the removal target portion of the resist film 11 corresponding to the light emitting portion L ₁ of at least an organic EL element, first The exposure process is performed a plurality of times by the first exposure process and the second exposure process.

According to this, the portion corresponding to the light emitting portion L ₁ of at least an organic EL element, since the exposure process for a plurality of times is performed in order to completely remove the positive resist film 11, due to the unexposed resist film 11 The formation of local protrusions of the conductive film can be avoided, and problems such as leakage of the organic EL element can be prevented in advance.

  In addition, in the panel substrate of the organic EL panel described above, the conductive film layers 10A and 10B are formed of a laminate of a plurality of conductive films, and the wiring pattern portion 5 is drawn out from the sealing portion of the organic EL element. In addition, a lead electrode is formed.

According to this, the portion of the extraction electrode can be a low-resistance wiring structure composed of a laminate of a plurality of conductive films, and when forming the wiring pattern portion 5 of this wiring structure, as described above, at least the portion corresponding to the light emitting portion L ₁ of the organic EL element, since the exposure process for a plurality of times is performed in order to completely remove the positive resist film 11, the local conductive film due to the unexposed resist film 11 Therefore, it is possible to avoid formation of a protruding portion, and to prevent occurrence of problems such as leakage of the organic EL element.

  Moreover, in the method for manufacturing an organic EL panel described above, the first exposure step and the second exposure step are repetitions of exposure using a photomask for forming the wiring pattern portion 5. Features.

  According to this, by performing repeated exposure, it is possible to eliminate a portion of insufficient exposure, and if necessary, by changing exposure conditions such as a light irradiation angle, a portion to be removed of the resist film 11 Can be reliably avoided.

  In addition, in the method for manufacturing an organic EL panel described above, the photomask 20 is replaced for each exposure process.

  According to this, even if the photomask 20 used in the first exposure process has deposits such as foreign matters and the unexposed portion of the resist film 11 is removed, the photomask is used in the second exposure process. By replacing 20, even if foreign matter or the like adheres to the photomask 20 that has been replaced, it is considered that this does not overlap with the foreign matter adhesion portion of the previous photomask 20. Unexposed portions can be reliably avoided.

  In addition, in the above-described organic EL panel manufacturing method, a single photomask is used, and the arrangement is slightly shifted for each exposure process.

  According to this, even if the photomask 20 used in the first exposure process has deposits such as foreign matters and the unexposed portion of the resist film 11 is removed, the photomask is used in the second exposure process. By shifting the arrangement of 20, the unexposed portion in the first exposure step can be exposed in the second exposure step. Therefore, it is possible to reliably avoid unexposed portions of the resist film 11 to be removed.

Moreover, in the organic EL panel manufacturing method described above, the first exposure step is exposure using a photomask 21 for forming the wiring pattern portion 5, and the second exposure step is organic. characterized in that it is a light exposure using a photomask 22 having a pattern corresponding to a part or the whole in the light emitting region L ₀ of the EL panel.

According to this, patterning is performed for the wiring pattern 5 using a photomask 21 in the first exposure step, the second time so that no unexposed areas in the light-emitting area L ₀ of the organic EL panel in the second exposure step Exposure can be performed. Therefore, since the second exposure process can be performed regardless of the pattern formation in the first exposure process, there is no pattern shift associated with the two exposures, and only the light emitting region L ₀ that is important for leak countermeasures. A plurality of exposures can be performed with different photomasks, and unexposed portions of the resist film 11 to be removed can be reliably avoided.

  Since each embodiment of the present invention has such a feature, in the above-described organic EL panel panel substrate and organic EL panel manufacturing method, the occurrence of problems such as leakage due to the remaining of the removed resist film is prevented in advance. This makes it possible to improve the product yield and solve problems after product shipment such as an increase in the non-lighting area and an increase in power consumption as the operating time elapses.

  It is as follows when each part aspect of the organic electroluminescent panel which concerns on embodiment of this invention is appended.

a. Support substrate;
The support substrate 1 may be a flat plate or a film having transparency, but is not limited to this, and various forms can be employed. In addition to the glass substrate, various materials such as plastic, quartz, wood, and paper can be used as the material.

b. Electrodes (lower electrode, upper electrode, wiring electrode (lead electrode));
Any of the lower electrode 2 formed on the support substrate 1 and the upper electrode 3 formed on the organic material layer 4 may be set as an anode or a cathode. The anode is made of a material having a work function higher than that of the cathode, such as a metal film such as chromium (Cr), molybdenum (Mo), nickel (Ni), platinum (Pt), indium oxide (In ₂ O ₃ ), ITO, IZO, etc. The transparent conductive film is used. Conversely, the cathode is made of a material having a work function lower than that of the anode, and is made of a metal film such as aluminum (Al) or magnesium (Mg), an amorphous semiconductor such as doped polyaniline or doped polyphenylene vinylene, Cr ₂ O ₃ , NiO, Mn ₂ O _{5 and} other oxides can be used. In general, the light extraction side is formed of a transparent electrode, but the lower electrode 2 and the upper electrode 3 are both formed of a transparent material, and a reflection film can be provided on the electrode side opposite to the light emission side.

The wiring electrodes 2A and 3B forming the extraction electrodes are formed of the first conductive films 2A ₁ and 3B ₁ with the same material as the lower electrode 2 (for example, transparent electrodes such as ITO and IZO), and Ag, Cr are formed thereon. It may be formed by laminating a plurality of such metals or their alloys, or the same material as the single layer of the lower electrode or the upper electrode, for example, a single layer of chromium single film, aluminum single film, ITO single film, etc. It may be a single layer film made of a material different from the film or the upper and lower electrodes. Preferred examples in the case of a laminated body include a two-layer structure of ITO (or IZO) / Ag—Pd, a three-layer structure of ITO (or IZO) / AgO / Ag, and 3 of ITO (or IZO) / Cr / Ag. Although it is a layer structure etc., not only this but what kind of material and laminated structure may be employ | adopted.

c. Organic material layer;
As described above, the organic material layer 4 is generally formed of an organic light emitting functional layer including a hole transport layer 4a, a light emitting layer 4b, and an electron transport layer 4c. In addition to the hole transport layer 4a and the electron transport layer 4c, either layer may be omitted or both layers may be omitted. It is also possible to insert organic functional layers such as a hole injection layer and an electron injection layer depending on the application.

  The organic material layer 4 is laminated by a wet process such as a coating method such as a spin coating method or a dipping method, a printing method such as an ink jet method or a screen printing method, or a dry process such as a vapor deposition method or a laser transfer method. be able to. The material of the light emitting layer 4b includes light emission (fluorescence) when returning from the singlet excited state to the ground state and light emission (phosphorescence) when returning from the triplet excited state to the ground state. In the embodiment of the present invention, The present invention can be applied to an organic EL panel using either light emission.

d. Various types of organic EL panels;
The display method of the organic EL panel may be single color light emission or multi-color light emission of two or more colors. In particular, in order to realize a multi-color light emission organic EL panel, a method of forming three types of light emitting functional layers corresponding to RGB For forming two or more light-emitting functional layers including a color (coloring method), a method in which a color conversion layer made of a color filter or a fluorescent material is combined with a monochromatic light-emitting functional layer such as white or blue (CF method, CCM method) A system that realizes multiple light emission by irradiating electromagnetic waves to the light emitting area of a single color light emitting functional layer (photo bleaching system), a system in which two or more sub-pixels are stacked vertically to form one pixel (SOLED) (Transparent stracked OLED) method). Further, the driving method of the organic EL element may be not only the passive driving method as described above but also the active driving method, and the light extraction method is opposite to the bottom emission method in which light is extracted from the support substrate 1 side and the support substrate 1. Either the top emission method of extracting light from the side may be used.

  Hereinafter, as a specific example of the present invention, an example of a method for manufacturing an organic EL panel using the present invention will be described. Needless to say, the present invention is not limited to this embodiment.

<Pretreatment process>
First, as shown in FIG. 5, a substrate 1 (glass, plastic, etc.) having a transparent conductive film 10A ₁ (ITO, IZO, etc.) and a metal conductive film 10B ₁ (Cr, Al, Ag, etc.) laminated on the upper surface is provided. prepare. Preferably, the transparent conductive film 10A ₁ is made of ITO, the metal conductive film 10B ₁ is made of Cr, and the substrate 1 is made of glass. When glass is used for the substrate, if the glass contains an impure element (alkali metal, Ca, Na, etc.), the buffer layer 1A (SiO2) is formed on the surface of the glass substrate in order to block the impregnation of the impure element. ₂ , TiO _2, etc.).

Next, as shown in FIG. 6 (FIG. 6A is a plan view and FIG. 6B is an AA cross-sectional view), the substrate 1 / buffer layer 1A (SiO ₂ ) / transparent conductive film 10A ₁ (ITO) The metal conductive film 10B ₁ is patterned by photolithography on the layer laminated with the metal conductive film 10B ₁ (Al) to form wiring electrode patterns 30A, 30B, 30C for the upper electrode and the lower electrode. In the illustrated example, wiring electrode patterns 30A, 30B, and 30C are formed on the multi-sided substrate 1M.

  At this time, in order not to form a resist film residue, a photomask having a wiring electrode pattern is arranged at the first exposure position and the first exposure process is performed, and the photomask is shifted to the second exposure position and the second time. The exposure process is performed. Further, this may be repeated to perform a plurality of exposure processes.

The following, FIG. 7 (FIG. (A) is a plan view, FIG. (B) is sectional view taken along line B-B) as shown in, photolithography transparent conductive film 10B ₁ that is exposed on the substrate 1 By patterning, a part of the pattern 31 of the lower electrode and the wiring electrode is formed. Also at this time, the photomask having the pattern 31 is arranged at the first exposure position and the first exposure process is performed so that the resist film residue is not formed, and the photomask is shifted to the second exposure position to obtain the second exposure position. A second exposure process is performed. Further, this may be repeated to perform a plurality of exposure processes.

  At this time, the surface of the lower electrode may be polished and smoothed, or the lower electrode surface may be chemically etched with a lower etchant concentration of the lower electrode to smooth the surface. .

  Then, as shown in FIG. 8 (FIG. 8A is a plan view and FIG. 8B is a CC cross-sectional view), an insulating film 32 such as photosensitive polyimide is formed by photolithography between the lines of the lower electrode. Patterning. As in the illustrated example, a partition wall (upper electrode separator) 33 for patterning the upper electrode may be formed, and the upper electrode may be formed using a film formation mask without forming such a partition wall 33. Patterning is also possible. Thereafter, if necessary, a UV cleaning process is performed to remove organic substances and moisture on the surface of the substrate 1.

<Film formation process>
FIG. 9 is a schematic explanatory diagram of a film forming apparatus. The substrate 1 that has undergone the pretreatment process described above is transferred into the film forming apparatus 40. In the film forming apparatus 40, a vapor deposition source (vapor deposition cell or crucible) 42 for forming an organic material layer by vapor deposition is disposed in a film deposition chamber (chamber) 41 in which a vacuum is maintained. A film formation mask 43 supported by the mask frame is provided. The substrate 1 is mounted above the deposition mask 43 and the deposition mask 43 is brought into close contact with the substrate 1 by the adsorption action of the magnet unit 44 installed above the substrate 1. When the vapor deposition source 42 is heated by the heating means 45 with the substrate 1 placed in this manner, the film deposition material 46 emitted from the vapor deposition source 42 is applied to the film deposition surface 1S of the substrate 1 through the film deposition mask 43. The organic material layer pattern is formed by vapor deposition.

The organic material layer may be any material as long as it can form an organic EL element. For example, a hole transport layer, an organic light emitting layer, an electron transport layer, etc. are laminated in a single layer or composite layer structure. Is done. As the organic material to be used, CuPc, NPB, Alq ₃ or the like is selected according to the function. Further, when the organic light emitting layer is a full color organic EL element, the organic light emitting layer can be formed in various patterns corresponding to the color of each pixel, and further, a hole transport layer, an electron transport layer, etc. The film may be formed to a film thickness adjusted to correspond to the color.

As an example of the film formation process, CuPc is deposited as a hole injection layer by 50 nm on the substrate 1 that has undergone the above-described pretreatment process on which the insulating film 32 is formed. , 4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD) is laminated to 50 nm. Further, RGB light emitting layers are separately formed in each light emitting layer film forming region using a film forming mask having a pattern. As a B (blue) light emitting layer, 4,4′-bis (2,2-diphenylvinyl) -biphenyl (DPVBi) host material and 4,4′-bis (2-carbazol vinylene) biphenyl as a 1 wt% dopant (BCzVBi) is co-evaporated to 50 nm, coumarin 6 is deposited to a thickness of 50 nm as a G (green) light emitting layer, and a tris (8-quinolinol) aluminum (Alq ₃ ) host is used as an R (red) light emitting layer. 4-Dicyanomethylene-2-methyl-6- (p-dimethylaminostillin) -4H-pyran (DCM) is co-evaporated to 50 nm as a 1 wt% dopant on the material. On top of this, 20 nm of Alq ₃ is deposited as an electron transport layer and 150 nm of aluminum (Al) is deposited as a cathode.

<Sealing process>
FIG. 10 is an explanatory view showing an organic EL panel sealed by a sealing process. The substrate 1 on which the organic EL element 50 is formed after the organic material film forming step is subjected to the light emission inspection step, and is then carried from the vacuum film forming chamber 41 into the N ₂ inert gas atmosphere sealing chamber. A sealing step is performed. At this time, a recess 51A is formed on the surface by blasting, and a glass sealing substrate 51 having a drying means (SrO) 53 installed in the recess 51A is also carried into the sealing chamber. On the sealing substrate 51, an adhesive 52 made of an ultraviolet curable epoxy resin in which an appropriate amount of 0.1 to 0.5% by weight of a glass spacer having a particle diameter of 1 to 300 μm is mixed in the peripheral adhesive portion. The sealing substrate 51 coated with the adhesive 52 and the substrate 1 on which the organic EL element 50 is formed are bonded to each other through the adhesive 52, and ultraviolet rays are applied to the substrate 1 side or the sealing substrate 51. The sealing step is completed by irradiating the adhesive 52 from the side and curing it.

<Effect of Example>
In the organic EL panel manufactured in this way, there is no resist residue when patterning the lower electrode or the wiring electrode as compared with the organic EL element by the conventional forming method, and it is possible to suppress the leakage of the organic EL element as much as possible. become.

It is explanatory drawing of the organic electroluminescent panel used as the premise of embodiment of this invention. It is explanatory drawing explaining the formation process of the panel board | substrate which concerns on embodiment of this invention. It is explanatory drawing explaining the manufacturing method of the organic electroluminescent panel which concerns on embodiment of this invention. It is explanatory drawing explaining the photomask used for the manufacturing method of the organic electroluminescent panel which concerns on embodiment of this invention. It is explanatory drawing of an Example. An explanatory view of the example (the figure (a) is a top view and the figure (b) is an AA sectional view). An explanatory view of the example (the figure (a) is a top view and the figure (b) is a BB sectional view). An explanatory view of the example (the figure (a) is a top view and the figure (b) is a CC sectional view). It is a schematic explanatory drawing of the film-forming apparatus. It is explanatory drawing which shows the organic electroluminescent panel sealed by the sealing process.

Explanation of symbols

1 supporting substrate 2 lower electrode 3 upper electrode 4 organic material layer 2A, 3A, 3B wiring electrodes 2A _1, 3B ₁ first conductive film 2A _2, 3B ₂ second conductive film 10A, 10B conductive film layer 11 a resist film 11b resist film Pattern 20, 21, 22 Photomask L ₀ light emitting area L ₁ light emitting part

Claims (10)

An organic EL element in which an organic material layer including an organic light emitting layer is sandwiched between a lower electrode and an upper electrode is formed on a support substrate, and an organic layer that forms a wiring electrode extending from the lower electrode and the upper electrode An EL panel substrate,
When forming the wiring pattern portion according to the pattern of the resist film formed by removing the exposed portion on the conductive film layer forming the wiring electrode,
An organic EL panel substrate, wherein an exposure process is performed a plurality of times on at least a part of the removal target portion of the resist film.   2. The organic EL panel substrate according to claim 1, wherein a part of the removal target part is a part corresponding to at least a light emitting part of the organic EL element.   3. The conductive film layer according to claim 1, wherein the conductive film layer is formed of a laminate of a plurality of conductive films, and the wiring pattern portion forms a lead electrode drawn from a sealing portion of the organic EL element. The described panel substrate for an organic EL panel.   The organic EL panel which uses the board | substrate for organic EL panels described in any one of Claims 1-3 as a support substrate. An organic EL element in which an organic material layer including an organic light emitting layer is sandwiched between a lower electrode and an upper electrode is formed on a support substrate, and an organic layer that forms a wiring electrode extending from the lower electrode and the upper electrode A method of manufacturing an EL panel,
When forming the wiring pattern portion according to the pattern of the resist film formed by removing the exposed portion on the conductive film layer forming the wiring electrode,
A first exposure step of exposing a portion to be removed of the resist film formed on the conductive film layer;
And a second exposure step of exposing at least a part of the removal target portion of the resist film corresponding to the light emitting portion of the organic EL element.   6. The method of manufacturing an organic EL panel according to claim 5, wherein the first exposure step and the second exposure step are repeated exposure using a photomask for forming the wiring pattern portion. .   The method of manufacturing an organic EL panel according to claim 6, wherein the photomask is replaced for each exposure process.   7. The method of manufacturing an organic EL panel according to claim 6, wherein a single photomask is used and the arrangement is slightly shifted for each exposure process.   The first exposure step is exposure using a photomask for forming the wiring pattern portion, and the second exposure step is a photomask having a pattern corresponding to at least a part of the light emitting region of the organic EL panel. The method for producing an organic EL panel according to claim 5, wherein the exposure is performed by using the above.   The first exposure step is exposure using a photomask for forming the wiring pattern portion, and the second exposure step uses a photomask having a pattern corresponding to the entire light emitting region of the organic EL panel. 6. The method for producing an organic EL panel according to claim 5, wherein the exposure is performed.

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