KR20200113712A - The cleaning method of metal mask for organic electroluminescent device and metal mask using the same - Google Patents

Abstract

Provided are a cleaning method of a metal mask and a metal mask cleaned by the same. The cleaning method of the metal mask comprises the steps of: providing a metal mask to which an environmental foreign material or an organic light-emitting material is attached; and supplying a current to an electrode immersed in an electrolyte after immersing the metal mask in the electrolyte. The current is used in a manufacturing process of an organic electroluminescent device supplied in a pulse method or a reverse pulse method.

Description

Metal mask cleaning method for organic light emitting display device and metal mask using the same {THE CLEANING METHOD OF METAL MASK FOR ORGANIC ELECTROLUMINESCENT DEVICE AND METAL MASK USING THE SAME}

The present disclosure relates to a method of cleaning a metal mask used in a manufacturing process of an organic light emitting display device and a metal mask cleaned by the method.

The demand for a display device that outputs image information is also increasing in various forms, and accordingly, LCD (Liquid Crystal Display), PDP (Plasma Display Panel), OLED (Organic Luminescent Emission Diode, hereinafter, organic light emitting diode) Display devices), VFD (Vacuum Fluorescent Display), and other flat panel display devices have been researched and developed.

Among such flat panel display devices, the organic light emitting display device uses an organic light emitting layer, which is a self-luminous element that emits phosphor through recombination of electrons and holes, and has a contrast ratio and response time. It is attracting attention as the most ideal next-generation display due to its excellent display characteristics and easy implementation of a flexible display.

The organic light emitting display device is configured by arranging a plurality of pixel regions in a matrix form, and a micro pattern such as a driving element for driving each pixel is formed in each pixel region.

At this time, in the case of the organic light-emitting layer that emits light, since it is made of an organic material with poor chemical resistance, an organic material is vaporized rather than a photolithography method using conventional exposure and etching, and a mask for deposition of an organic light-emitting display device is used. It is formed by selectively depositing it on a substrate by using. However, since the organic material is also deposited on the surface of the organic light emitting display device deposition mask that selectively screens the substrate during the deposition process, cleaning the organic light emitting display device deposition mask after a certain number of processes has passed. Is required.

In an organic light emitting display device, an anode electrode is formed on a substrate by lithography including exposure and etching processes, and an organic thin film and a cathode electrode are formed by depositing on the substrate on which the anode electrode is formed using a deposition mask made of metal. .

However, when multiple depositions are performed using the deposition mask as described above, deposition materials such as organic materials are deposited on the surface of the deposition mask, and if the deposition mask on which the deposition material is deposited continues to be left unattended, contamination in the chamber occurs. .

In addition, the evaporation mask made of a thin metal plate is bent by the weight of the deposited evaporation material, which affects the precision of the pattern. Therefore, it is necessary to regularly remove the deposition material deposited on the deposition mask.

An exemplary embodiment is to provide a method of cleaning a metal mask used in a manufacturing process of an organic light emitting display device capable of securing stable cleaning power by minimizing polarization through removal of hydrogen gas.

Another embodiment is to provide a metal mask cleaned by the cleaning method.

One embodiment includes providing a metal mask to which an environmental foreign substance or organic light-emitting material is attached, and after immersing the metal mask in an electrolyte, supplying current to an electrode contained in the electrolyte, wherein the current is pulsed. Alternatively, a method of cleaning a metal mask used in a manufacturing process of an organic light emitting display device supplied in a reverse pulse method is provided.

The temperature of the electrolyte solution may be 20 ℃ to 100 ℃.

The current may have a current density of 1.5A/dm ² to 25A/dm ² .

The cleaning time may be 3 minutes to 120 minutes.

The cleaning method may further include the step of providing additional bubbles by a bubble supply device.

The cleaning method may further include applying ultrasonic waves by an ultrasonic generator.

The metal mask is made of invar or stainless steel, the electrolyte solution includes an alkali salt, a water-soluble organic acid salt, and an inhibitor to reduce damage to the metal mask, and the inhibitor is thiourea, 123-benzotriazole or pyridine It may contain a system compound.

The alkali salt may include hydroxide, carbonate, silicate or phosphate, and the organic acid salt may include citrate, succinate, acetate, or glycolate.

Providing the metal mask may include disposing the metal mask on a substrate for forming an organic light emitting display device; Forming a pattern made of the organic material on the substrate by using the metal mask; And separating the metal mask from the substrate.

Another embodiment provides a metal mask cleaned by a method of cleaning the metal mask.

Other specifics of aspects of the present invention are included in the detailed description below.

According to the cleaning method according to an embodiment, since mask cleaning and hydrogen gas removal can be performed at the same time, a polarization phenomenon can be minimized and a stable cleaning power can be secured.

1 is a diagram showing a waveform of a rectifier when a pulse method is applied.
2 is a diagram showing a waveform of a rectifier when the reverse pulse method is applied.
3 is a diagram showing a waveform of a rectifier when a conventional direct current (DC) method is applied.
4 is a graph showing a photoresist residue removal rate according to a temperature change.
5 is a graph showing a photoresist residue removal rate according to a change in current.
6 is a graph showing a photoresist residue removal rate over time.

Hereinafter, embodiments of the present invention will be described in detail. However, this is presented as an example, and the present invention is not limited thereby, and the present invention is only defined by the scope of the claims to be described later.

Embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below. In addition, embodiments of the present invention are provided in order to more completely explain the present invention to those having average knowledge in the art. Accordingly, the shapes and sizes of elements in the drawings may be exaggerated for clearer explanation, and elements indicated by the same reference numerals in the drawings are the same elements.

Throughout this specification, when a certain part "includes" a certain component, it means that other components may be further included rather than excluding other components unless otherwise stated.

A process of forming an organic electroluminescence display device (hereinafter referred to as an organic EL) includes depositing and patterning various materials on a substrate.

In particular, in order to form the organic EL, an organic light emitting pattern that generates red, green, and blue light must be formed on a substrate (eg, a glass substrate).

In this case, a metal mask is disposed on the substrate, and the organic light-emitting body pattern is formed using the metal mask.

The metal mask is a conductor, and is made of invar or stainless steel. A plurality of hole patterns corresponding to the organic light-emitting body pattern are formed in the metal mask.

At this time, environmental foreign matter is attached to the metal mask, so that an organic light-emitting body pattern different from the pattern to be formed on the substrate may be formed.

Examples of the environmental foreign matter include residues of a photoresist used to manufacture the metal mask, residues of a tape used to wrap the metal mask, and residues that may be attached during a transfer or cleaning process.

Also, the metal mask may be used several times to form the organic light emitting panel. In this case, a material used as the organic light-emitting body pattern is attached to the metal mask, and thus a defect may be caused in manufacturing the organic EL.

In addition, various substances may be attached to the metal mask.

Accordingly, several methods have been proposed for cleaning the metal mask, and the metal mask is generally cleaned in a power supply. Specifically, DC voltage (negative voltage) is applied to the metal mask to be cleaned through the cathode terminal, and DC voltage (positive voltage) is applied to the anode electrode. Unlike this, a positive voltage is applied to the metal mask. Also, a negative voltage may be applied to the electrode. In this case, examples of the material that can be used as the electrode include iridium oxide, titanium, platinum, or nickel. Conventionally, the mask is cleaned by continuously supplying current for a certain period of time (DC method; see Fig. 3). When the current is continuously supplied as described above, hydrogen gas generated on the surface of the metal mask forms a film (2H ⁺ + 2e → H). ₂ ) As a result, the current efficiency is lowered, and thus the cleaning power is reduced (polarization phenomenon), and there is a side that is insufficient to perform clean cleaning of the metal mask, and thus there is a great difficulty in reusing the metal mask.

However, according to one embodiment, by supplying current in a pulsed or reverse pulsed manner instead of a conventional DC method, the hydrogen gas generated from the surface of the metal mask is given time to be removed, thereby minimizing the occurrence of polarization to ensure a stable metal mask. Detergency can be secured.

Specifically, an embodiment includes providing a metal mask to which an environmental foreign substance or an organic light-emitting material is attached, and after immersing the metal mask in an electrolyte solution, supplying a current to an electrode immersed in the electrolyte solution, and the current Provides a method of cleaning a metal mask used in a manufacturing process of an organic light emitting display device supplied in a pulse manner. (See Fig. 1)

The pulse method is to clean the metal mask by repeating the steps of “supplying for a certain period of time, stopping for a certain period of time, and supplying for a certain period of time”. If the current is repeatedly supplied, stopped, and supplied, the cathode ( Metal mask) When hydrogen gas is generated on the surface, the metal mask is cleaned, and in the section in which the supply of current is stopped, the generation of polarization is minimized by giving time for the hydrogen gas to be removed, thereby securing stable cleaning power.

In addition, one embodiment includes providing a metal mask to which an environmental foreign material or organic light-emitting material is attached, and after immersing the metal mask in an electrolyte, supplying a current to an electrode contained in the electrolyte, the current being reversed. A method of cleaning a metal mask used in a manufacturing process of an organic light emitting display device supplied in a pulse manner is provided. (See Fig. 2)

In the reverse pulse method, a positive voltage is instantaneously applied to the metal mask by supplying a reverse current very short. When a positive voltage is momentarily applied to the metal mask, it has the effect of very finely polishing the surface of the metal mask. The oxide film can be removed. In addition, since it is possible to have a time for the hydrogen gas to be removed, the polarization phenomenon can be minimized. After the reverse current is supplied for a very short time, the process of flowing the forward current is repeated to clean the metal mask.

The temperature of the electrolyte solution may range from 20°C to 100°C, and in this case, the current may have a current density of 1.5A/dm ² to 25A/dm ² , and the cleaning time may be 3 minutes to 120 minutes. When the metal mask cleaning method according to the embodiment is performed within the range of the temperature of the electrolyte solution, the current density, and the cleaning time, more than 99% of the photoresist residue can be removed, thereby maximizing the cleaning power of the metal mask. . Specifically, the metal mask must be cleaned within the range of the temperature of the electrolyte solution, the current density, and the cleaning time, so that the solubility of foreign matters on the surface of the metal mask in the electrolyte solution remains sufficiently high (good for electrical decomposition). State), the cleaning power of the metal mask can be maximized.

For example, the cleaning method may further include the step of providing additional bubbles by a bubble supply device.

For example, the cleaning method may further include applying ultrasonic waves by an ultrasonic generator.

When the metal mask cleaning method according to an embodiment further includes the step of applying bubbles or ultrasonic waves, a metal mask deposition material such as an organic material may be more efficiently removed.

The metal mask is made of invar or stainless steel, the electrolyte solution includes an alkali salt, a water-soluble organic acid salt, and an inhibitor to reduce damage to the metal mask, and the inhibitor is thiourea, 123-benzotriazole or pyridine It may contain a system compound.

The alkali salt may include hydroxide, carbonate, silicate, or phosphate. Here, the salt may refer to an alkali metal such as sodium or potassium or an alkaline earth metal such as calcium and barium. In addition, the salt may refer to ammonium and the like. The alkali salt forms strong conductive ions that remove the organic material by electrolysis. In addition, the alkali salt makes the electrolyte solution highly alkaline.

The organic acid salt may include citrate, succinate, acetate or glycolate. The water-soluble organic salt functions as a buffer to prevent the pH of the electrolyte solution from rapidly changing. In addition, the water-soluble organic salt auxiliaryly removes the environmental foreign matter or organic light-emitting material. In addition, the water-soluble organic salt serves to prevent the precipitation of hydroxide of metal ions, thereby sustaining the cleaning effect of the electrolyte.

The inhibitor prevents the surface of the metal mask from being damaged by corrosion or overreaction by the electrolyte. The inhibitor may include thiourea, 123-benzotriazole, or pyridine-based compounds. In this case, the pyridine-based compound may be a nitrogen or sulfur compound having an unshared electron pair.

Additionally, the electrolyte may contain a surfactant or the like. The surfactant has excellent emulsifying effect and prevents re-adhesion of the organic material.

For example, the electrolyte may contain about 20 g/l to 100 g/l of potassium hydroxide, about 7 g/l to 50 g/l of potassium citrate, and about 0.08 g/l to 5 g/l of thiourea. have.

For example, the providing of the metal mask may include disposing the metal mask on a substrate for forming an organic light emitting display device; Forming a pattern made of the organic material on the substrate by using the metal mask; And separating the metal mask from the substrate.

According to another embodiment, a cleaned metal mask is provided by a method of cleaning the metal mask.

Hereinafter, preferred embodiments of the present invention will be described. However, the following examples are only preferred examples of the present invention, and the present invention is not limited by the following examples.

(Example)

Cleaning power evaluation

Example 1

First, the electrolyte is in the form of an aqueous solution, and contains 40 g/l of potassium hydroxide, 10 g/l of potassium citrate, and 0.1 g/l of thiourea.

In addition, the temperature of the electrolyte solution proceeded at 0° C., and voltage was applied to the metal mask and the electrode through a power supply device so that a current having a current density of 1.5 A/dm ² flows through the metal mask in a pulse manner.

The time lasted for 3 minutes, and a negative voltage was applied to the metal mask.

As the metal mask, a metal mask made of Invar was used, and a photoresist was attached to the metal mask.

Example 2

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 5°C.

Example 3

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 10°C.

Example 4

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 15°C.

Example 5

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 20°C.

Example 6

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 25°C.

Example 7

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 30°C.

Example 8

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 40°C.

Example 9

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 50°C.

Example 10

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 70°C.

Example 11

It was the same as in Example 1, except that the temperature of the electrolyte solution was set to 100°C.

Example 12

It was the same as in Example 5, except that the current density was set to 0.1 A/dm ² .

Example 13

It was the same as in Example 5, except that the current density was set to 0.3 A/dm ² .

Example 14

It was the same as in Example 5, except that the current density was set to 0.5 A/dm ² .

Example 15

It was the same as in Example 5, except that the current density was set to 1 A/dm ² .

Example 16

It was the same as in Example 5, except that the current density was set to 2 A/dm ² .

Example 17

It was the same as in Example 5, except that the current density was set to 5 A/dm ² .

Example 18

It was the same as in Example 5, except that the current density was set to 10 A/dm ² .

Example 19

It was the same as in Example 5, except that the current density was set to 15 A/dm ² .

Example 20

It was the same as in Example 5, except that the current density was set to 20 A/dm ² .

Example 21

It was the same as in Example 5, except that the current density was set to 25 A/dm ² .

Example 22

It was carried out in the same manner as in Example 5, except that the washing time was set to 10 seconds.

Example 23

It was carried out in the same manner as in Example 5, except that the washing time was set to 30 seconds.

Example 24

It was carried out in the same manner as in Example 5, except that the washing time was set to 1 minute.

Example 25

It was carried out in the same manner as in Example 5, except that the washing time was set to 2 minutes.

Example 26

It was carried out in the same manner as in Example 5, except that the washing time was 5 minutes.

Example 27

It was the same as in Example 5, except that the washing time was 10 minutes.

Example 28

It was carried out in the same manner as in Example 5, except that the washing time was 30 minutes.

Example 29

It was carried out in the same manner as in Example 5, except that the washing time was 60 minutes.

Example 30

It was carried out in the same manner as in Example 5, except that the washing time was set to 90 minutes.

Example 31

It was carried out in the same manner as in Example 5, except that the washing time was set to 120 minutes.

Example 1-1

It was the same as in Example 1, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-2

It was the same as in Example 2, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-3

It was the same as in Example 3, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-4

It was the same as in Example 4, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-5

It was the same as in Example 5, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-6

It was the same as in Example 6, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-7

It was the same as in Example 7, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-8

It was the same as in Example 8, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-9

It was the same as in Example 9, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-10

It was the same as in Example 10, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-11

It was the same as in Example 11, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-12

It was the same as in Example 12, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-13

It was the same as in Example 13, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-14

It was the same as in Example 14, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-15

It was the same as in Example 15, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-16

It was the same as in Example 16, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-17

It was the same as in Example 17, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-18

It was the same as in Example 18, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-19

It was the same as in Example 19, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-20

It was the same as in Example 20, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-21

It was the same as in Example 21, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-22

It was the same as in Example 22, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-23

It was the same as in Example 23, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-24

It was the same as in Example 24, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-25

It was the same as in Example 25, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-26

It was the same as in Example 26, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-27

It was the same as in Example 27, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-28

It was the same as in Example 28, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-29

It was the same as in Example 29, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-30

It was the same as in Example 30, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Example 1-31

It was the same as in Example 31, except that the current was made to flow in a reverse pulse method instead of a pulse method.

Comparative Example 1

It was the same as in Example 1, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 2

It was the same as in Example 2, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 3

It was the same as in Example 3, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 4

It was the same as in Example 4, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 5

It was the same as in Example 5, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 6

It was the same as in Example 6, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 7

It was the same as in Example 7, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 8

It was the same as in Example 8, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 9

It was the same as in Example 9, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 10

It was the same as in Example 10, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 11

It was the same as in Example 11, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 12

It was the same as in Example 12, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 13

It was the same as in Example 13, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 14

It was the same as in Example 14, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 15

It was the same as in Example 15, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 16

It was the same as in Example 16, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 17

It was the same as in Example 17, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 18

It was the same as in Example 18, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 19

It was the same as in Example 19, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 20

It was the same as in Example 20, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 21

It was the same as in Example 21, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 22

It was the same as in Example 22, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 23

It was the same as in Example 23, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 24

It was the same as in Example 24, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 25

It was the same as in Example 25, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 26

It was the same as in Example 26, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 27

It was the same as in Example 27, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 28

It was the same as in Example 28, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 29

It was the same as in Example 29, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 30

It was the same as in Example 30, except that the current was made to flow in a DC method instead of a pulse method.

Comparative Example 31

It was the same as in Example 31, except that the current was made to flow in a DC method instead of a pulse method.

Evaluation: cleaning power

Through the SEM equipment, the cleaning power (photoresist residue removal rate) was evaluated based on the photoresist residue removal rate, and the results are shown in Tables 1 to 9 and FIGS. 4 to 6 below.

Example One 2 3 4 5 6 7 8 9 10 11 Cleaning power (%) 73 79 85 91 100 100 100 100 100 100 100

Example 12 13 14 15 16 17 18 19 20 21 Cleaning power (%) 3 21 54 80 100 100 100 100 100 100

Example 22 23 24 25 26 27 28 29 30 31 Cleaning power (%) 8 26 52 82 100 100 100 100 100 100

Example 1-1 1-2 1-3 1-4 1-5 1-6 1-7 1-8 1-9 1-10 1-11 Cleaning power (%) 81 85 90 95 100 100 100 100 100 100 100

Example 1-12 1-13 1-14 1-15 1-16 1-17 1-18 1-19 1-20 1-21 Cleaning power (%) 4 29 60 86 100 100 100 100 100 100

Example 1-22 1-23 1-24 1-25 1-26 1-27 1-28 1-29 1-30 1-31 Cleaning power (%) 9 35 66 90 100 100 100 100 100 100

Comparative example One 2 3 4 5 6 7 8 9 10 11 Cleaning power (%) 59 67 72 75 83 83 84 84 85 87 88

Comparative example 12 13 14 15 16 17 18 19 20 21 Cleaning power (%) One 14 47 65 83 85 86 84 88 90

Comparative example 22 23 24 25 26 27 28 29 30 31 Cleaning power (%) 4 14 40 67 84 84 84 85 86 87

From Tables 1 to 9 and FIGS. 4 to 6, it can be seen that the cleaning power is excellent when the cleaning method according to an embodiment is used. In particular, it can be seen that cleaning power can be maximized by limiting the cleaning temperature, current, and time to a specific range.

The present invention is not limited to the above embodiments, but may be manufactured in a variety of different forms, and a person of ordinary skill in the art to which the present invention pertains may not change the technical spirit or essential features of the present invention, It will be appreciated that it can be implemented with. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not limiting.

Claims (11)

Providing a metal mask to which an environmental foreign material or an organic light-emitting material is attached, and
After immersing the metal mask in the electrolyte, supplying current to an electrode immersed in the electrolyte,
A method of cleaning a metal mask used in a manufacturing process of an organic light emitting display device in which the current is supplied in a pulse manner.
Providing a metal mask to which an environmental foreign material or an organic light-emitting material is attached, and
After immersing the metal mask in the electrolyte, supplying current to an electrode immersed in the electrolyte,
A method of cleaning a metal mask used in a manufacturing process of an organic light emitting display device in which the current is supplied in a reverse pulse method.
In claim 1 or 2,
A method of cleaning a metal mask in which the temperature of the electrolyte solution is 20°C to 100°C.
In paragraph 3,
The current is a method of cleaning a metal mask having a current density of 1.5A/dm ² to 25A/dm ² .
In claim 4,
The cleaning time is a method of cleaning a metal mask of 3 minutes to 120 minutes.
In claim 1 or 2,
The cleaning method further comprises the step of applying additional bubbles by a bubble supply device.
In claim 1 or 2,
The cleaning method further comprises applying ultrasonic waves by an ultrasonic generator.
In claim 1 or 2,
The metal mask is made of Invar or stainless steel,
The electrolyte solution includes an alkali salt, a water-soluble organic acid salt, and an inhibitor for reducing damage to the metal mask,
The inhibitor is a method for cleaning a metal mask containing thiourea, 123-benzotriazole or a pyridine-based compound.
In clause 8,
The alkali salt includes hydroxide, carbonate, silicate or phosphate, and the organic acid salt includes citrate, succinate, acetate or glycolate.
In claim 1 or 2,
Providing the metal mask
Disposing the metal mask on a substrate for forming an organic light emitting display device;
Forming a pattern made of the organic material on the substrate by using the metal mask; And
And separating the metal mask from the substrate.
A metal mask cleaned by the method of cleaning the metal mask of claim 1 or 2.

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