JP2009295461A - Manufacturing method of indium tin oxide layer, and manufacturing method of electro-optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem that, when an ITO layer is used as a transparent electrode, there is a case wherein a foreign matter having conductivity is formed and if such foreign matter is generated, it penetrates through an organic light-emitting layer of a thickness of several tens of nm in the organic EL device, and makes electrical short circuit with a counter electrode to generate a region which is not displayed, and that in the region which is connected by a wiring with a location electrically short-circuited, a linear defect is generated by the voltage drop caused by electrical short circuit and becomes a factor to deteriorate the display quality. <P>SOLUTION: The ITO layer is washed by hot water having a temperature of 30°C or more and 60°C or less. The foreign matter produced secondarily at the time the ITO layer is formed has a different composition to the ITO, and contains an oxide of excessive tin, thereby it reacts with hot water and is separated from the ITO layer. On the other hand, the ITO layer has resistance to the hot water, thereby the foreign matter can be removed selectively. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an ITO layer manufacturing method and an electro-optical device manufacturing method.

  In an electro-optical device such as a liquid crystal device or an organic EL (electroluminescence) device, an ITO (indium / tin / oxide) layer serving as a transparent electrode is used as an electrode. There are few transparent substances having conductivity, and the ITO layer plays an important role as a transparent electrode.

  When the ITO layer is used as a transparent electrode, conductive foreign matter may be formed. When such a foreign matter is generated, particularly in an organic EL device, an organic light emitting layer having a layer thickness of several tens of nm is penetrated to be electrically short-circuited with the counter electrode, thereby generating a region that is not displayed. Further, in a region where the electrically shorted place and the wiring are connected, a line defect is generated due to a voltage drop caused by the electrical short circuit, which causes the display image quality to deteriorate.

  In order to suppress such a phenomenon, when manufacturing an organic EL device, a process called laser repair is performed. Specifically, an operation of lighting all the pixels of the organic EL device is performed, a non-light emitting organic EL element is detected, and an operation of subsequently irradiating a laser beam to isolate a defective portion is performed. Specifically, in order to avoid foreign matters with unknown composition, the periphery of the foreign matter is burned out with a laser and electrically separated. This technique is publicly known and described in, for example, Patent Document 1.

JP 2005-276600 A

  When the laser burn-out technique is used, the burned-out area is always in a black state, and there is a problem that the image quality of the organic EL device is deteriorated. In addition, every time the organic EL device has a large screen, the load on the dark spot search / repair process increases, which becomes a big problem especially when the screen is enlarged. In addition, when a short circuit occurs in a fine region, there is a problem that the time required to detect the position becomes long.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples. Here, “warm water” includes those obtained by heating pure water or ultrapure water.

  Application Example 1 An ITO layer manufacturing method according to this application example includes a step of washing an ITO (indium / tin / oxide) layer with warm water having a temperature of 30 ° C. or more and 60 ° C. or less. .

  According to this, it is possible to selectively remove foreign substances that are generated secondaryly when the ITO layer is formed. The secondary foreign matter has a composition different from that of the ITO layer and contains an oxide containing excess tin, so that it can be peeled off from the ITO layer by reacting with warm water. On the other hand, the ITO layer is resistant to hot water. Therefore, it is possible to selectively remove foreign matters. In this case, the foreign matter can be removed at a practical speed by washing with warm water having a temperature of 30 ° C. or higher. And it becomes possible to suppress the damage given to an ITO layer by wash | cleaning with 60 degreeC or less warm water, and generation | occurrence | production of the nonuniformity by vapor | steam can be suppressed to the minimum.

  [Application Example 2] The manufacturing method of the ITO layer according to this application example includes a step of cleaning the ITO layer with an acidic cleaning liquid and a step of cleaning with warm water having a temperature of 30 ° C or higher and 60 ° C or lower. .

  According to this, it is possible to selectively remove foreign substances that are generated secondaryly when the ITO layer is formed. The secondary foreign matter contains a tin-excess oxide having a composition different from that of the ITO layer. Therefore, the foreign matter can be selectively reacted with the ITO cleaning solution in a selective ratio with the ITO layer. Therefore, the adhesion between the foreign matter and the ITO layer can be reduced. By performing the warm water cleaning in this state, the foreign matter whose adhesiveness with the ITO layer is lowered reacts with the hot water and is peeled off. On the other hand, since the ITO layer is resistant to warm water, foreign substances can be selectively removed. In this case, the foreign matter can be removed at a practical speed by washing with warm water having a temperature of 30 ° C. or higher. And it becomes possible to suppress the damage given to an ITO layer by washing | cleaning with warm water of 60 degrees C or less, and generation | occurrence | production of the nonuniformity by a vapor | steam, etc. can be suppressed to the minimum.

  [Application Example 3] In the manufacturing method of the ITO layer described above, the acidic cleaning liquid is phosphoric acid, nitric acid, acetic acid, hydrochloric acid, sulfuric acid, or a mixture thereof, or a liquid obtained by diluting the mixture with water, or phosphoric acid, It is a liquid obtained by diluting nitric acid, acetic acid, hydrochloric acid, and sulfuric acid alone with water.

  According to the application example described above, it is possible to selectively remove foreign matters with a combination of materials that are preferably used in the manufacturing process of an electro-optical device using an ITO layer. Further, by washing with an acidic cleaning liquid and then with warm water, the acidic cleaning liquid can be removed from the ITO layer, and the next step can be performed without acid contamination.

  Application Example 4 The manufacturing method of the ITO layer according to this application example includes a step of cleaning the ITO layer with electrolytic oxidation water and a step of cleaning with warm water having a temperature of 30 ° C. or more and 60 ° C. or less. To do.

  According to this, it is possible to selectively remove foreign substances that are generated secondaryly when the ITO layer is formed. The secondary foreign matter contains an indium-excess material having a composition different from that of the ITO layer. Therefore, the foreign matter can be selectively reacted with the electrolytically oxidized water by taking a selectivity with the ITO layer. Therefore, the adhesion between the foreign matter and the ITO layer can be reduced. By performing the warm water cleaning in this state, the foreign matter whose adhesiveness with the ITO layer is lowered reacts with the hot water and is peeled off. On the other hand, since the ITO layer is resistant to warm water, foreign substances can be selectively removed. In this case, the foreign matter can be removed at a practical speed by washing with warm water having a temperature of 30 ° C. or higher. And it becomes possible to suppress the damage given to an ITO layer by washing | cleaning with warm water of 60 degrees C or less, and generation | occurrence | production of the nonuniformity by a vapor | steam, etc. can be suppressed to the minimum.

  [Application Example 5] The manufacturing method of the ITO layer according to this application example includes a step of washing the ITO layer with electrolytic oxidation water and a step of washing with an acidic cleaning solution in any order, and a temperature of 30 ° C to 60 ° C. Washing with warm water having the following.

  According to this, it is possible to remove foreign matters caused by tin-excess oxide and indium-excess material. The tin-excess oxide can be selectively reacted with the ITO layer using an acidic cleaning solution, and can be reacted selectively to reduce the adhesion between the foreign matter and the ITO layer. The indium-excess material can be selectively reacted with the ITO layer using electrolytic oxidation water, and can be selectively reacted to reduce the adhesion between the foreign matter and the ITO layer. By performing the warm water cleaning in this state, the foreign matter whose adhesiveness with the ITO layer is lowered reacts with the hot water and is peeled off. On the other hand, since the ITO layer is resistant to warm water, foreign substances can be selectively removed. In this case, the foreign matter can be removed at a practical speed by washing with warm water having a temperature of 30 ° C. or higher. And it becomes possible to suppress the damage given to an ITO layer by washing | cleaning with warm water of 60 degrees C or less, and generation | occurrence | production of the nonuniformity by a vapor | steam, etc. can be suppressed to the minimum.

  Application Example 6 In the manufacturing method of the ITO layer described above, the acidic cleaning liquid is phosphoric acid, nitric acid, acetic acid, hydrochloric acid, sulfuric acid, a mixed solution thereof, a liquid obtained by diluting the mixed solution with water, or phosphoric acid. Nitric acid, acetic acid, hydrochloric acid, and sulfuric acid simple substance diluted with water.

  According to the application example described above, it is possible to selectively remove foreign matters with a combination of materials that are preferably used in the manufacturing process of an electro-optical device using an ITO layer. In addition, after washing with an acidic cleaning solution or electrolytic oxidation water, the acidic cleaning solution or electrolytic oxidation water can be removed from the ITO layer by washing with warm water, and the next step can be performed without acid contamination. It becomes possible.

  Application Example 7 The manufacturing method of the ITO layer described above is characterized in that the electrolytically oxidized water is manufactured using an aqueous ammonium carbonate solution.

  According to the application example described above, the electrolytically oxidized water can be produced without using an alkali metal or an alkaline earth metal. Therefore, it is possible to reliably suppress contamination of the semiconductor layer that drives the ITO layer due to alkali metal or alkaline earth metal.

  Application Example 8 A method for manufacturing an electro-optical device according to this application example includes the above-described ITO layer manufacturing method.

  According to this manufacturing method, the number of foreign matters remaining in the ITO layer can be reduced as compared with the case where the above-described ITO layer manufacturing method is not used, and a method for manufacturing an electro-optical device with excellent image quality is provided. It becomes possible.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

(Electrolytic oxidation water supply device)
First, the electrolytic oxidation water supply device used in this embodiment will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view illustrating the function performed by the electrolytically oxidized water supply device. The electrolytic oxidation water supply apparatus 200 includes an electrolyte container 201, an electrolytic oxidation water container 202, an electrolytic reduction water container 203, ion exchange membranes 204 and 205, an anode 206, a cathode 207, and a power source 208.

A saturated aqueous solution of ammonium carbonate is disposed in the electrolyte container 201, electrolytic oxidized water is disposed in the electrolytic oxidized water container 202, and electrolytic reduced water is disposed in the electrolytic reduced water container 203. Hereinafter, the generation mechanism of electrolytic oxidation water will be described. In an initial state, pure water is disposed in the electrolytic oxidation water container 202 and the electrolytic reduction water container 203, and a saturated aqueous solution of ammonium carbonate is disposed in the electrolyte container 201. When electrons are supplied from the power source 208 to the cathode 207 and current is supplied so as to suck up electrons from the anode 206, the following reaction occurs on the anode 206 side due to electrolysis of water.
2H ₂ O → O ₂ + 4H ⁺ + 4e ⁻
In addition, since carbonate ions enter through the ion exchange membrane 204, the following reaction also occurs.
2 (CO ₃ ) ²⁻ → 2CO ₂ + O ₂ + 4e ⁻
By the reaction described above, the water in the electrolytically oxidized water container 202 is acidic and becomes electrolytically oxidized water having higher oxidizability. The pH of the electrolytically oxidized water is, for example, about 2 to 3, and the redox potential (ORP) has a value of, for example, about 900 (mV vs. Ag / AgCl). On the cathode 207 side, the following reaction occurs due to water electrolysis.
2H ₂ O + 2e ⁻ → 2OH ⁻ + H ₂
In addition, since ammonium ions enter through the ion exchange membrane 205, the following reaction also occurs.
2 (NH ₄ ) ⁺ + 2e ⁻ → 2NH ₃ + H ₂
By the reaction described above, the water in the electrolytically reduced water container 203 is alkaline and becomes electrolytically reduced water having higher reducing properties. The pH of the electrolytically reduced water is, for example, about 10, and the oxidation-reduction potential (ORP) has a value of, for example, about −700 (mV vs. Ag / AgCl).

  By supplying such electrolyzed oxidized water, it becomes possible to supply electrolyzed oxidized water without using alkali metal or alkaline earth metal. Here, the concentration of ammonium carbonate is not necessarily a saturated aqueous solution, and it is possible to provide electrolytic oxidized water even if the concentration is lowered. In addition, when sufficient cleaning can be performed in a subsequent process, a solution containing an alkali metal or an alkaline earth metal can be placed in the electrolyte container 201 for generating electrolytic oxidized water.

(Parallel plate type sputtering equipment)
Next, an apparatus for forming an ITO layer according to this embodiment will be described. FIG. 2 is a cross-sectional view showing the configuration of the parallel plate sputtering apparatus 300. The parallel plate sputtering apparatus 300 includes an anode 301, a chamber 302, a gas introduction unit 303, an exhaust unit 304, a cathode 305, an ITO target 306, a magnet 307, and an RF power source 308.

  The anode 301 cooperates with the cathode 305 to generate plasma using high-frequency power supplied from the RF power source 308. The RF power supply 308 also has a function of supplying a DC bias voltage, and a bias voltage is applied between the anode 301 and the cathode 305. The plasma state is controlled by the magnetic field generated by the magnet 307.

  The gas introduction unit 303 supplies, for example, Ar gas as a sputtering gas. Then, the pressure inside the chamber 302 is controlled in cooperation with the exhaust unit 304. The chamber 302 is controlled so that the internal pressure is maintained at a pressure of about 50 Pa.

  The plasma generated between the anode 301 and the cathode 305 sputters the ITO target 306. The sputtered ITO is deposited on the glass substrate 1 to form an ITO layer 2.

  The parallel plate sputtering apparatus 300 has a simple structure and is excellent in maintainability, and can form the ITO layer 2 with high stability.

(Production method of ITO layer-1: washing process using warm water)
Hereinafter, after forming the ITO layer 2, a method for manufacturing the ITO layer including a cleaning process using warm water to remove foreign matters that cause defects in an organic EL device or the like will be described. 3A and 3B are schematic cross-sectional views for explaining a situation in which foreign matter is removed by hot water cleaning.

  First, a thin film transistor (hereinafter referred to as TFT) or the like (not shown) is formed on one surface of a substrate body 1A using glass or the like, and a glass substrate 1 on which an interlayer insulating layer is formed is 220 ° C. Bake for 60 minutes. By performing this step, adhesion between the ITO layer 2 and the glass substrate 1 described later is improved.

  Next, the ITO layer 2 is formed by mounting on the parallel plate sputtering apparatus 300 described above. Here, instead of the parallel plate type sputtering apparatus 300, a vapor deposition apparatus or a plasma coating apparatus may be used. In this step, foreign matter 402A is generated as a secondary. A cross-sectional view showing this state is shown in FIG.

  Next, in order to modify the ITO layer 2 formed on the glass substrate 1, baking is performed at 220 ° C. for 60 minutes. By baking, the ITO layer 2 is crystallized, chemical resistance is improved, and it is less likely to be damaged in the foreign matter removing process described later. Note that this baking step can be omitted, and the chemical resistance of the ITO layer 2 is reduced by omitting the baking step, but the chemical resistance of the foreign matter 402A is also reduced at the same time. It is possible to take a selection ratio between. In the present embodiment, the description will be continued for the case where a step of baking at 220 ° C. for 60 minutes is performed in order to modify the ITO layer 2.

The foreign matter is predominantly different from the composition of the ITO layer 2 and contains, for example, a tin-excess oxide (foreign matter 402A). Since the composition of the foreign matter 402A and the ITO layer 2 is different, it is possible to ensure a selection ratio between the ITO layer 2 and the foreign matter 402A. Therefore, it is possible to selectively remove foreign matters by the cleaning process. Specifically, when the glass substrate 1 on which the ITO layer 2 is formed is immersed in warm water having a temperature of 30 ° C. or more and 60 ° C. or less as a temperature at which the selection ratio can be taken between the ITO layer 2 and the foreign matter 402A, Such a reaction occurs.
SnO + H ₂ O⇔SnO ₂ + 2H ⁺
FIG. 3B is a cross-sectional view schematically illustrating a process in which the foreign matter 402A is peeled off from the ITO layer 2 by this reaction. Since the chemical reaction rate of the foreign matter 402A is faster than that of the ITO layer 2, the selectivity between the foreign matter 402A and the ITO layer 2 can be taken. As a result of this reaction, the adhesion strength of the foreign matter 402 </ b> A to the ITO layer 2 decreases, and the foreign matter 402 </ b> A peels off from the ITO layer 2. That is, it is possible to provide a manufacturing method of the ITO layer 2 that can selectively remove foreign matters by performing the above-described steps. In addition, you may add the process of wash | cleaning using ultrapure water etc. of normal temperature after warm water washing | cleaning.

(Production method of ITO layer-2: cleaning process using acidic cleaning liquid and warm water)
Hereinafter, after forming the ITO layer 2, a method for manufacturing the ITO layer 2 including a cleaning process using an acidic cleaning liquid and a cleaning process using warm water to remove the foreign matter 402 </ b> A that causes defects in an organic EL device or the like is illustrated. 4 will be described. FIGS. 4A to 4C are process cross-sectional views for explaining a process of removing foreign matter using the cleaning process according to the present embodiment. In the following description, the same parts as those described above are omitted in order to avoid duplication. Here, a process cross-sectional view after forming the ITO layer 2 is shown in FIG.

The foreign matter is predominantly different from the composition of the ITO layer 2 and contains, for example, a tin-excess oxide (foreign matter 402A). Since the composition of the foreign matter 402A and the ITO layer 2 is different, it is possible to ensure a selection ratio between the ITO layer 2 and the foreign matter 402A. Therefore, the foreign matter 402A can be selectively removed in the cleaning process. Specifically, for example, when the glass substrate 1 on which the ITO layer 2 is formed is immersed using phosphoric acid, mainly nitric acid and acetic acid, as an acidic cleaning solution, the following reaction occurs.
SnO ₂ + 2H ⁺ + 2e-⇔SnO + H ₂ O
Since the chemical reaction rate of the foreign matter 402A is faster than that of the ITO layer 2, the selectivity between the foreign matter 402A and the ITO layer 2 can be taken. And by this reaction, the adhesion strength between the foreign matter 402A and the ITO layer 2 is lowered. A process cross-sectional view after this process is shown in FIG. And the foreign material 402A peels by immersing the glass substrate 1 in which the ITO layer 2 was formed in the warm water which has the temperature of 30 to 60 degreeC. That is, the foreign matter 402A can be selectively removed. FIG. 4C is a cross-sectional view schematically illustrating a process in which the foreign matter 402A is peeled off from the ITO layer 2 by this reaction. By washing with warm water having a temperature of 30 ° C. or higher, foreign matter can be removed at a practical speed. In this case, it is possible to suppress damage to the ITO layer 2 by washing with hot water of 60 ° C. or less, and generation of unevenness due to steam can be minimized. Moreover, it becomes possible to remove the acidic cleaning liquid from the glass substrate 1 by performing the warm water treatment after the acidic cleaning liquid treatment, and it is no longer affected by the substance caused by the acidic cleaning liquid in the next step, so the cleanliness is maintained. It becomes possible.

  As the acidic aqueous solution used here, a general acid such as lactic acid or citric acid can be used. Among them, phosphoric acid, nitric acid, acetic acid, hydrochloric acid, sulfuric acid, or a mixed solution thereof, or the above-mentioned mixed solution can be used. It is preferable to use a liquid obtained by diluting the liquid with water, or a liquid obtained by diluting phosphoric acid, nitric acid, acetic acid, hydrochloric acid, or sulfuric acid alone with water, and the organic EL device 10 in the electro-optical device including the ITO layer 2 (see FIG. 8). The foreign matter 402A can be selectively removed by a combination of substances used in the manufacturing process (1). Therefore, it is possible to avoid the occurrence of unexpected contamination due to the introduction of a new substance. It becomes possible to provide the manufacturing method of the ITO layer 2 which can selectively remove a foreign material by performing the above-mentioned process. In addition, you may add the process of wash | cleaning using ultrapure water etc. of normal temperature after warm water washing | cleaning.

(Production method of ITO layer-3: washing process using electrolytically oxidized water and warm water)
Hereinafter, after the ITO layer 2 is formed, a manufacturing method of the ITO layer 2 including a cleaning process using electrolytic oxidation water and a cleaning process using warm water to remove foreign matters that cause defects in an organic EL device or the like will be described. To do. FIGS. 5A to 5C are schematic cross-sectional views for explaining a situation in which foreign matter is removed by electrolytic oxidation water cleaning and hot water cleaning. In the following description, the same parts as those described above are omitted in order to avoid duplication.

In the foreign matter, there is a foreign matter 402B having a composition close to that of metallic indium in addition to the foreign matter 402A as a tin-excess oxide. A cross-sectional view in the state where 402B exists is shown in FIG. For the removal of the foreign matter 402B, it is preferable to use electrolytic oxidized water, and it is possible to secure a selection ratio between the ITO layer 2 and the foreign matter 402B. As the electrolytically oxidized water, one having a pH of about 2 to 3 and a redox potential (ORP) of about 900 (mV vs. Ag / AgCl) can be used, for example. In this case, the following reaction occurs, and the bonding state of the foreign matter 402B to the ITO layer 2 is loosened.
In → In ³⁺ + 3e ⁻
In ³⁺ + OH ⁻ → InOH ²⁺

  On the other hand, the ITO layer 2 is resistant to the electrolytically oxidized water and can take a selection ratio with the foreign matter 402B. And by this reaction, the adhesion strength between the foreign matter 402B and the ITO layer 2 is lowered. A process cross-sectional view in this state is shown in FIG. Here, the foreign matter 402B is separated from the ITO layer 2 by being immersed in warm water having a temperature of 30 ° C. or higher and 60 ° C. or lower. FIG. 5C is a process cross-sectional view schematically illustrating a process in which the foreign matter 402B is peeled from the ITO layer 2 by this reaction.

  As a substance used for the production of electrolytic oxidized water, sodium chloride or the like may be used when sufficient cleaning can be performed to remove alkali metal. In order to reliably prevent alkali metal contamination, it is preferable to use an electrolyte that does not use an alkali metal, such as ammonium carbonate. By performing the above-described steps, it is possible to provide a method for manufacturing the ITO layer 2 that can selectively remove foreign substances. In addition, you may add the process of wash | cleaning using ultrapure water etc. of normal temperature after warm water washing | cleaning.

(Production method of ITO layer-4: cleaning process using acidic cleaning solution, electrolytic oxidation water and warm water)
Hereinafter, after forming the ITO layer 2, a cleaning process using an acidic cleaning liquid, a cleaning process using electrolytic oxidation water, and hot water were used to remove foreign matters 402A and 402B that cause defects in an organic EL device or the like. A method for manufacturing the ITO layer 2 including the cleaning step will be described with reference to FIG. In the following description, the same parts as those described above are omitted in order to avoid duplication. 6A to 6D are process cross-sectional views illustrating a process of removing foreign matter after the ITO layer 2 is formed.

  Here, the cleaning process using the acidic cleaning liquid and the electrolytically oxidized water can be performed in any order. Here, the cleaning process using the electrolytically oxidized water is performed after the cleaning process using the acidic cleaning liquid, and the temperature is 30 ° C. or higher and 60 ° C. or lower. The case where it processes with the warm water which has is demonstrated. Moreover, you may insert another process between the washing | cleaning process using electrolytic oxidation water, and the washing | cleaning process using warm water.

  When the ITO layer 2 is formed on the glass substrate 1, foreign substances 402A and 402B are formed as secondary as shown in FIG. Here, when cleaning is first performed using an acidic cleaning solution, the adhesion strength between the foreign matter 402A and the ITO layer 2 decreases as shown in FIG. 6B. Next, the acidic cleaning solution is replaced by washing with water. Here, warm water of 30 ° C. or more and 60 ° C. or less may be used. In this case, the foreign matter 402A can be removed in this step. Further, the step of replacing the acidic cleaning solution can be omitted, and the next step may be performed with the acidic cleaning solution attached to the glass substrate 1. In the present embodiment, the description of the case of washing at room temperature is continued. After washing with water, when washed with electrolytically oxidized water, the adhesion strength between the foreign matter 402B and the ITO layer 2 decreases. This state is shown in FIG. Next, it wash | cleans using 30 degreeC or more and 60 degrees C or less warm water. By this step, the foreign matters 402A and 402B are removed. This state is shown in FIG. By using this ITO layer 2 manufacturing process, it is possible to provide a method for manufacturing the ITO layer 2 that can remove both the tin-excess foreign matter and the indium-excess foreign matter. In addition, you may add the process of wash | cleaning using ultrapure water etc. of normal temperature after warm water washing | cleaning.

(Target structure of parallel plate type sputtering equipment)
Hereinafter, the structure of the ITO target 306 in the parallel plate sputtering apparatus 300 for forming the ITO layer 2 will be described. FIGS. 7A and 7B are plan views for explaining the planar structure of the ITO target 306 described in FIG. For example, when the glass substrate 1 having a side of 500 mm is used, it is necessary to use about three unit ITO targets 306A as shown in FIG.

  When the parallel plate sputtering apparatus 300 is used, it is necessary to use an ITO target 306 having an area comparable to the dimension of the glass substrate 1. In this case, it is necessary to arrange a plurality of unit ITO targets 306A in a tile shape, but foreign matters 402A and 402B as shown in FIG. 6A are generated from the joints of the unit ITO targets 306A. Here, as the size of the glass substrate 1 increases, the desired size of the ITO target 306 increases, but it is difficult to increase the size of the unit ITO target 306A due to manufacturing problems.

  Here, if the foreign matter 402A, 402B can be removed as described above, the ITO layer 2 from which the foreign matter 402A, 402B has been removed can be obtained even if the unit ITO target 306A is made small. Thus, the unit ITO target 306A can be configured. FIG. 7B is a plan view in which unit ITO targets 306A are spread to form an enlarged ITO target 306N. As shown in FIG. 7B, the size of the glass substrate 1 is increased. For example, even when an ITO target 306N having a side of 1000 mm is used, the size of the unit ITO target 306A is increased by removing the foreign matters 402A and 402B. The ITO target 306N can be configured without any problem.

(Method for manufacturing electro-optical device)
Hereinafter, as an application example using the method for manufacturing the ITO layer 2, a method for manufacturing an organic EL device as an electro-optical device will be described. FIG. 8 is an equivalent circuit diagram of the organic EL device 10 including the ITO layer 2. Here, “up” refers to the upward direction of each drawing.

  The organic EL device 10 shown in FIG. 8 has TFTs 122 and 123 as switching elements. In the case of using an active matrix system using TFTs 122 and 123, a plurality of scanning lines 101, a plurality of signal lines 102 extending in a direction intersecting with each scanning line 101, and a plurality of signal lines 102 extending in parallel with each signal line 102 are used. And the sub-pixel 40 is provided in the vicinity of each intersection of the scanning line 101 and the signal line 102.

  A data line driving circuit 100 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 102. Further, a scanning line driving circuit 80 including a shift register and a level shifter is connected to the scanning line 101. Each of the sub-pixels 40 includes a switching TFT 122 in which a scanning signal is supplied to the gate electrode via the scanning line 101, and a storage capacitor that holds a pixel signal shared with the signal line 102 via the switching TFT 122. 113. When a pixel signal held by the holding capacitor 113 is electrically connected to the power supply line 103 via the TFT 123 for driving supplied to the gate electrode and the TFT 123, a drive current is given from the power supply line 103. An organic EL element 17 (R, G, B) sandwiched between the pixel electrode 23 and the counter electrode 50 facing the pixel electrode 23 is provided.

  Hereinafter, a method for manufacturing the organic EL device 10 will be described. 9A to 9D are process cross-sectional views for explaining a method for manufacturing the organic EL device 10, and FIG. 10 is a plan view of the organic EL device 10 manufactured using the manufacturing method shown below. is there.

  First, the ITO layer 2 is manufactured using the parallel plate sputtering apparatus 300 (see FIG. 2) on the glass substrate 1 including the TFT 122 and the TFT 123 (see FIG. 8) on which the interlayer insulating layer 401 is formed. . Here, instead of the parallel plate type sputtering apparatus 300, a vapor deposition apparatus or a plasma coating apparatus may be used. In this step, a foreign matter 402A containing a tin-excess oxide and a foreign matter 402B having a composition close to that of metallic indium are produced as secondary components. A cross-sectional view showing this state is shown in FIG.

  When the foreign matters 402A and 402B remain, a black line is generated due to a short circuit between the ITO layer 2 serving as the anode and the cathode 219 (see FIG. 9D), and the image quality of the organic EL device 10 is degraded. When black line-like defects occur, it is necessary to search for and remove the short-circuited part, and particularly in an organic EL device with a large screen and high definition, the time required for this correction process is long. Therefore, productivity is reduced. Further, even if the black line defect is corrected, the black spot defect remains and the deterioration of the image quality is inevitable. Here, the load on the dark spot search / repair process can be suppressed by chemically removing the foreign matter from the transparent electrode.

  Next, the glass substrate 1 on which the ITO layer 2 is formed is cleaned with an acidic cleaning solution. And it wash | cleans using 30 degreeC or more and 60 degrees C or less warm water. By performing this cleaning, the foreign matter 402A can be removed. FIG. 9B shows the state after this process. Here, after washing with warm water, a process of washing with room-temperature ultrapure water or the like may be added.

  Next, the glass substrate 1 on which the ITO layer 2 is formed is cleaned using electrolytic oxidation water. And it wash | cleans using 30 degreeC or more and 60 degrees C or less warm water. By performing this cleaning, the foreign matter 402B can be removed. FIG. 9C shows the state after this process. Here, after washing with warm water, a process of washing with room-temperature ultrapure water or the like may be added.

  Next, after forming the first partition 215 and the second partition 216, the hole transport layer 217 and the organic light emitting layer 218 are formed using a manufacturing process such as a droplet discharge method. Then, the cathode 219 and the metal electrode 220 are formed using a sputtering method or the like, and the organic EL element 17 (R, G, B) is formed. Then, the organic EL device 10 including the organic EL elements 17 (R, G, B) is formed by being connected to the data line driving circuit 100 and the like. FIG. 9D shows the state after this process. Since the organic EL device 10 removes the foreign matters 402A and 402B that lead to line defects in advance, the number of defects can be suppressed. Therefore, it is possible to provide a method for manufacturing the organic EL device 10 with good display quality.

  Next, the organic EL device 10 will be described with reference to FIG. As shown in FIG. 10, in the actual display region 4 of the glass substrate 1, the organic EL elements 17 (R, G, and R) included in the sub-pixels 40 (see FIG. 8) provided corresponding to R, G, and B are provided. B) is regularly arranged in a matrix. Then, a pixel 41 is configured with a set of sub-pixels 40 corresponding to the organic EL elements 17 (R, G, B). In the present embodiment, the pixel unit 3 (within the dashed-dotted line frame in the figure) includes an actual display area 4 (within the two-dot chain line frame in the figure) at the center part and a dummy area 5 (one point around the actual display area 4). And a region between a chain line and a two-dot chain line). A scanning line driving circuit 80 is arranged so as to sandwich the actual display area 4.

  In addition, an inspection circuit 90 is disposed above the actual display area 4. The inspection circuit 90 is a circuit for inspecting the operating state of the organic EL device 10, and includes, for example, inspection information output means (not shown) for outputting the inspection result to the outside, and a color organic in the middle of manufacture or at the time of shipment. It is configured so that the quality and defect inspection of the EL display can be performed. By using the manufacturing method of the organic EL device 10, occurrence of a short circuit between the electrodes in the organic EL element 17 (R, G, B) can be suppressed. Therefore, it is possible to provide a manufacturing method capable of manufacturing the organic EL device 10 that can obtain a high-quality image in which the generation of line defects is suppressed.

The schematic cross section explaining the function which an electrolytic oxidation water supply device fulfills. Sectional drawing which shows the structure of a parallel plate type | mold sputtering device. (A), (b) is a schematic cross section for demonstrating the condition which peels a foreign material by warm water washing | cleaning. Sectional drawing which modeled the process of peeling a foreign material from an ITO layer by washing | cleaning by an acidic washing | cleaning liquid, and warm water washing | cleaning. Sectional drawing which modeled the process of peeling a foreign material from an ITO layer by washing | cleaning by electrolytic oxidation water, and warm water washing | cleaning. (A)-(d) is process sectional drawing which shows the process of removing a foreign material, after forming an ITO layer. (A), (b) is a top view for demonstrating the planar structure of an ITO target. The equivalent circuit diagram of the organic electroluminescent apparatus containing an ITO layer. (A)-(d) is process sectional drawing for demonstrating the manufacturing method of an organic electroluminescent apparatus. The top view of an organic electroluminescent apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Glass substrate, 1A ... Substrate body, 2 ... ITO layer, 3 ... Pixel part, 4 ... Actual display area, 5 ... Dummy area, 10 ... Organic EL device, 17 ... Organic EL element, 23 ... Pixel electrode, 40 ... Sub-pixel, 50 ... counter electrode, 80 ... scanning line driving circuit, 90 ... inspection circuit, 100 ... data line driving circuit, 101 ... scanning line, 102 ... signal line, 103 ... power supply line, 113 ... holding capacitor, 122 ... TFT , 123 ... TFT, 200 ... Electrolytically reduced water supply device, 201 ... Electrolyte container, 202 ... Electrolyzed oxidized water container, 203 ... Electrolytically reduced water container, 204 ... Ion exchange membrane, 205 ... Ion exchange membrane, 206 ... Anode, 207 ... Cathode, 208 ... Power source, 215 ... First partition, 216 ... Second partition, 217 ... Hole transport layer, 218 ... Organic light emitting layer, 219 ... Cathode, 220 ... Metal electrode, 300 ... Parallel plate sputtering apparatus, 30 DESCRIPTION OF SYMBOLS ... Anode, 302 ... Chamber, 303 ... Gas introduction part, 304 ... Exhaust part, 305 ... Cathode, 306 ... ITO target, 306A ... Unit ITO target, 306N ... ITO target, 307 ... Magnet, 308 ... RF power supply, 401 ... Interlayer Insulating layer, 402A ... foreign matter, 402B ... foreign matter.

Claims (8)

  A method for producing an ITO layer, comprising a step of washing an ITO (indium / tin / oxide) layer with warm water having a temperature of 30 ° C. or more and 60 ° C. or less. Cleaning the ITO layer with an acidic cleaning solution;
The manufacturing method of the ITO layer characterized by including the process wash | cleaned with the warm water which has the temperature of 30 degreeC or more and 60 degrees C or less.   The method for producing an ITO layer according to claim 2, wherein the acidic cleaning liquid is phosphoric acid, nitric acid, acetic acid, hydrochloric acid, sulfuric acid, or a mixture thereof, or a liquid obtained by diluting the mixture with water, or phosphoric acid, A method for producing an ITO layer, which is a liquid obtained by diluting nitric acid, acetic acid, hydrochloric acid, and sulfuric acid alone with water. Cleaning the ITO layer with electrolytic oxidation water;
The manufacturing method of the ITO layer characterized by including the process wash | cleaned with the warm water which has the temperature of 30 degreeC or more and 60 degrees C or less. Cleaning the ITO layer with electrolytic oxidation water;
Washing with an acidic washing solution;
In any order,
And a step of washing with warm water having a temperature of 30 ° C. or higher and 60 ° C. or lower.   6. The method for manufacturing an ITO layer according to claim 5, wherein the acidic cleaning liquid is phosphoric acid, nitric acid, acetic acid, hydrochloric acid, sulfuric acid, or a mixture thereof, or a liquid obtained by diluting the mixture with water, or phosphoric acid. A method for producing an ITO layer, which is a liquid obtained by diluting nitric acid, acetic acid, hydrochloric acid, and sulfuric acid alone with water.   The method for producing an ITO layer according to claim 4 or 5, wherein the electrolytically oxidized water is produced using an aqueous ammonium carbonate solution.   A method for manufacturing an electro-optical device, comprising the method for manufacturing an ITO layer according to claim 1.

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