KR20220021676A - Stencil for printing process with fine patterns and manufacturing method of the same - Google Patents

Abstract

A stencil for a printing process in which a fine pattern is formed and a method for manufacturing the same are provided. According to an embodiment of the present invention, a through hole having a shape corresponding to the printed pattern is formed, and a fine pattern for reducing adhesion to the substrate is formed on the lower surface.

Description

Stencil for printing process with fine patterns and manufacturing method of the same

The present invention relates to a stencil for a printing process having a fine pattern formed therein and a method for manufacturing the same, and more particularly, to a stencil for a printing process having a fine pattern formed therein. It relates to a stencil for a printing process and a method for manufacturing the same.

Recently, in the electronic product production market, various attempts are being made to reduce production costs, improve material consumption efficiency, and establish a clean production environment through the introduction of a new production process. A typical example is printed electronic technology, which refers to a next-generation printing technology that uses a printing process to print electronic circuits, sensors, devices, and various electronic products. Printed electronic technology includes various printing processes such as inkjet printing, screen printing, roll-to-roll printing, and imprinting.

Among them, a method of printing metal ink by a screen printing method or a spray printing method is mainly used for printing a conductive circuit of a fine pattern.

However, the conventional screen printing method using a stencil combined with a screen mesh generally uses a screen mesh having a diameter of about 40 μm. In this case, when a pattern having a size smaller than the diameter of the screen mesh is printed, the printed pattern formed on the stencil is covered by the screen mesh, and a printing defect portion is generated depending on the position, thereby causing a problem of non-uniformity of the pattern.

In addition, in the conventional spray printing method, when the stencil is manufactured, the stencil is manufactured to have a predetermined thickness or more to maintain minimum rigidity. Therefore, the finer the pattern to be printed, the greater the height compared to the line width of the pattern, and the printing material printed through the stencil is caught between the print patterns of the stencil and is removed together in the process of removing the stencil, resulting in poor printing. there was

In order to solve this problem, in the 'micro stencil and its manufacturing method (Publication No. 10-2020-0043796)', a through-hole having a shape corresponding to a printed pattern is formed and protruding from one surface of the mask part, Disclosed is a micro stencil including a reinforcing part provided in a portion where a through hole is not formed.

However, according to the above method, since the mask part is supported by the reinforcing part and spaced apart from the substrate, the mask part does not come into contact with the printed metal ink, thereby preventing the metal ink from being caught in the through hole. Since there is a limit to print clearly, it is time to develop a new technology for this.

KR 10-2020-0043796 A

The present invention is to solve the above problems, and it is possible to secure the uniformity of the fine pattern, and to prevent the deterioration of the pattern quality due to the adhesion between the substrate and the stencil, the stencil for the printing process in which the fine pattern is formed, and its manufacture The purpose is to provide a method.

In order to achieve the above object, in the stencil for a printing process in which a fine pattern is formed according to an embodiment of the present invention, a through hole having a shape corresponding to the printing pattern is formed, and a fine pattern to reduce adhesion to the substrate is formed on the lower surface. to become a technical gist.

In addition, in order to achieve the above object, in the method for manufacturing a stencil for a printing process in which a fine pattern is formed according to an embodiment of the present invention, a first chrome pattern corresponding to the printed pattern and a transparent electrode layer are laminated on the upper surface of a glass substrate. A first step of preparing a substrate for an exposure process; a second step of manufacturing a photoresist pattern for reducing adhesion on the transparent electrode layer of the substrate for the exposure process; a third step of manufacturing a photoresist pattern for a stencil using the photoresist pattern for reducing adhesion; and a fourth step of manufacturing a stencil using the photoresist pattern for the stencil.

The first step of preparing the substrate for the exposure process of the stencil manufacturing method for the printing process on which the fine pattern is formed is the first- Step 1(a); and a step 1-2(a) of forming a transparent electrode layer on an upper surface of the first photomask.

The first step of preparing the substrate for the exposure process of the stencil manufacturing method for the printing process on which such a fine pattern is formed is Step 1-1, in which a transparent electrode layer and a chromium layer are sequentially formed on a glass substrate, and a photosensitizer is applied on the chromium layer. (b) step; A 1b photomask having a first chrome pattern formed thereon to correspond to the printed pattern is placed on top of the photosensitizer of step 1-1 (b), and a first 1-2 photoresist pattern is formed through ultraviolet irradiation and developing process. (b) step; and steps 1-3 (b) of forming a first chrome pattern by etching the chrome layer using the first photoresist pattern as a mask.

The second step of manufacturing the photosensitive agent pattern for reducing the adhesion of the stencil manufacturing method for the printing process in which such a fine pattern is formed is a step 2-1 (a) of forming a second photomask having a second chrome pattern formed thereon on a glass substrate ; a step 2-2 (a) of arranging the second photomask on top of the substrate for the exposure process to form a second photoresist pattern through ultraviolet irradiation and developing process; and a step 2-3(a) of heat-treating the second photosensitive agent pattern to form a micro-photosensitive agent pattern for reducing adhesion.

The second step of manufacturing the photosensitive agent pattern for reducing the adhesion of the stencil manufacturing method for the printing process in which such a fine pattern is formed is a step 2-1 (b) of forming a second photomask having a second chrome pattern formed thereon on a glass substrate ; Step 2-2 (b) of arranging the second photomask on top of the substrate on which the photosensitive agent is applied, and manufacturing a substrate for producing a phase mask on which a second photosensitive agent pattern is formed through ultraviolet irradiation and developing process; a step 2-3(b) of pouring and curing a transparent liquid polymer on the second photoresist pattern of the substrate for preparing the phase mask, and separating it to prepare a phase mask; a step 2-4 (b) of arranging the phase mask on top of the substrate for the exposure process to form a third photoresist pattern through ultraviolet irradiation and developing process; and a second-5 (b) step of heat-treating the third photoresist pattern to form a nano photoresist pattern for reducing adhesion.

The third step of manufacturing the pattern for the stencil of the stencil manufacturing method for the printing process in which the fine pattern is formed includes: a 3-1 step of applying a photosensitive agent to the top of the photosensitive agent pattern for reducing adhesion formed on the substrate for the exposure process; and a step 3-2 of forming a photoresist pattern for a stencil through a developing process of irradiating ultraviolet rays on the lower surface of the substrate for the exposure process.

In the fourth step of manufacturing the stencil of the stencil manufacturing method for the printing process in which such a fine pattern is formed, a metal electroplating process is performed on the photoresist pattern for the stencil to form a metal plating layer from the transparent electrode layer to manufacture the stencil. do it with

According to the present invention by means of a solution to the above problems, it is possible to prevent deterioration of pattern quality due to the adhesion between the substrate and the stencil by the fine pattern implemented on the lower surface of the stencil.

In addition, by performing an exposure process by irradiating ultraviolet rays from the back side of the glass substrate, a phenomenon in which a gap is generated between the chromium pattern of the photomask and the photosensitizer can be prevented, thereby solving the pattern non-uniformity.

1 is a flowchart of a stencil manufacturing method for a printing process in which a fine pattern is formed according to an embodiment of the present invention.
FIG. 2 is a view showing an embodiment of a step of preparing a substrate for an exposure process of FIG. 1 ;
FIG. 3 is a view showing another embodiment of a step of preparing a substrate for an exposure process of FIG. 1 .
4 is a view showing an embodiment in which the photosensitive agent pattern for reducing adhesion of FIG. 1 is implemented as a micro pattern;
5 and 6 are views showing an embodiment in which the photosensitive agent pattern for reducing adhesion of FIG. 1 is implemented as a nano-pattern;
FIG. 7 is a view showing an embodiment of implementing the photoresist pattern for a stencil of FIG. 1;
Fig. 8 is a diagram illustrating an embodiment implementing the stencil fabrication of Fig. 1;

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings 1 to 8. On the other hand, in the drawings and detailed description, a general photomask, a photosensitizer, a transparent electrode, an exposure process, a photolithography process Illustrations and references to configurations and actions that can be easily understood by those skilled in this field from others have been simplified or omitted. In particular, in the drawings and detailed descriptions, detailed descriptions and illustrations of specific technical configurations and actions of elements not directly related to the technical features of the present invention are omitted, and only the technical configurations related to the present invention are briefly illustrated or described. did

As shown in FIG. 1, the method of manufacturing a stencil for a printing process having a fine pattern according to an embodiment of the present invention includes a first step (S100) of preparing a substrate for an exposure process, a photoresist pattern for reducing adhesion and reducing adhesion. It consists of a second step (S200) of manufacturing, a third step (S300) of manufacturing the photoresist pattern for the stencil, and a fourth step (S400) of manufacturing the stencil.

First, in the first step (a), a substrate 200 for an exposure process is prepared. (S100)

In the exposure process substrate 200, as shown in FIG. 2, a transparent electrode layer 220 is formed on the 1a photomask 100a in which the first chrome pattern 110 is formed on the glass substrate.

At this time, the first chrome pattern 110 is formed to correspond to the printed pattern.

이하의 값을 갖는 범위 내에서 선택될 수 있다.In addition, as the transparent electrode layer 220 , a metal oxide layer including an indium tin oxide (ITO) thin film or a metal oxide-metal-metal oxide composite layer may be used. The thickness of the thin film of the transparent electrode layer 220 has a light transmittance of 70% or more in the ultraviolet region, and a sheet resistance of 20

It may be selected within a range having the following values.

이상일 경우, 추후 전주도금 공정 시 도금 두께의 균일도 저하를 유발할 수 있기 때문이다.This is because, when the light transmittance of the transparent electrode layer 220 is 70% or less, excessive light is required in applying the exposure process to the thick photoresist pattern, and thus the quality of the exposure pattern may be deteriorated. In addition, the sheet resistance is 20

This is because, in the case of abnormality, the uniformity of the plating thickness may be deteriorated during the subsequent electroplating process.

On the other hand, when the substrate 200 for the exposure process is formed by the above-described method, since the 1a photomask 100a is directly used as the substrate, there may be a problem in that the manufacturing cost increases due to problems such as damage. Accordingly, the first step (b), which is another embodiment of manufacturing the substrate 200 for the exposure process capable of solving this problem, will be described as follows.

3 , a transparent electrode layer 220 and a chromium layer 230 are sequentially formed on a glass substrate, and a photosensitizer is applied on the chromium layer 230 .

The 1b photomask 100b on which the first chrome pattern 110 corresponding to the printed pattern is formed is disposed on top of the photoresist, and the first photoresist pattern 240 is formed through ultraviolet irradiation and developing process.

When the chromium layer 230 is etched using the first photoresist pattern 240 as a mask, the substrate 200 for the exposure process on which the first chromium pattern 210 is formed can be manufactured in the same manner as the 1b photomask 100b. .

Next, the second step is a step of manufacturing the photoresist patterns 330 and 350 for reducing adhesion. (S200)

The photoresist patterns 330 and 350 for reducing adhesion are for implementing a micro pattern 630 to be formed on the lower surface of the stencil 600 later, and may be formed in a micro pattern or a nano pattern.

First, referring to FIG. 4, the second step (a) in the case of forming a micro-pattern is as follows.

A second photomask 300 having a second chrome pattern 310 formed thereon is manufactured on a glass substrate, and a photosensitizer is applied on the transparent electrode layer 220 of the substrate 200 for the exposure process prepared in the first step (S100). . A second photomask 300 is disposed on the upper end thereof to form a second photoresist pattern 320 through ultraviolet irradiation and development process.

Here, the thickness of the photoresist is preferably within a range of 0.5 to 5 times the line width of the second photoresist pattern 320 to be implemented. If the ratio of the thickness to the line width of the photosensitive agent is less than 0.5, the micropattern is formed too thinly to obtain an effect of reducing adhesion, and if the ratio of the thickness to the line width of the photosensitive agent is thicker than 5, the exposure pattern quality deteriorates in applying the exposure process There is this.

A reflow process of heat-treating the second photoresist pattern 320 thus formed is performed to implement the micro photoresist pattern 330 for reducing adhesion. At this time, the heat treatment temperature is preferably in the range of 120 to 160 ℃.

Meanwhile, the second step (b) in the case of forming a nano-pattern will be described with reference to FIGS. 5 and 6 .

A second photomask 300 having a second chrome pattern 310 formed thereon is manufactured on a glass substrate, and a photosensitizer is applied on the transparent electrode layer 220 of the substrate 200 for the exposure process prepared in the first step (S100). . A second photomask 300 is disposed on the upper end thereof to form a substrate 400 for producing a phase mask on which the second photoresist pattern 320 is formed through ultraviolet irradiation and development process.

Here, the thickness of the photosensitizer is preferably in the range of 1 to 5 μm. When the thickness of the photosensitizer is shallower than 1 μm, the phase mask 500 to be described later is thinly formed, so that the nano-pattern is difficult to appear. There is this.

A transparent liquid polymer is poured on the second photoresist pattern 320 of the substrate 400 for producing the phase mask prepared by the above method to cure, and then separated from the second photoresist pattern 320 to produce the phase mask 500 . do.

The curing method may be selected from heat or ultraviolet curing. In the case of thermosetting, the temperature is in the range of 40 to 100 ℃, in the case of UV curing, it is preferable that the amount of light irradiation is 100 to 2000 mJ/cm ² . If the thermosetting temperature is lower than 40°C or the amount of UV irradiation is lower than 100 mJ/cm ² , there is a problem that curing does not occur well, and if the thermosetting temperature is higher than 100°C or the UV curing temperature is higher than 2000 mJ/cm ² Since the shrinkage occurs, there is a problem in that the pattern of the phase mask 500 does not come out in a desired shape.

In addition, as the polymer used herein, PDMS (Polydimethylsiloxane) or Polyurethane may be mainly used, but the present invention is not limited thereto, and all materials that can be cured by heat or UV light and are suitable for pattern molding can be applied.

A photosensitizer is applied on the transparent electrode layer 220 of the substrate 200 for the exposure process manufactured in the first step (S100), and a phase mask 500 is disposed on the upper part of the third photoresist pattern through ultraviolet irradiation and development process. (340) is formed.

The third photoresist pattern 340 thus formed implements the nano photoresist pattern 350 for reducing adhesion by performing a reflow process of heat treatment. At this time, the heat treatment temperature is preferably in the range of 120 to 160 ℃.

As described above, as the photoresist patterns 330 and 350 for reducing adhesion, any one selected from the micro photosensitizer pattern 330 for reducing adhesion or the nano photoresist pattern 350 for reducing adhesion may be used, which will be described later with a fine pattern 630 . ) is implemented using the micro-photosensitizer pattern 330 for reducing adhesion, the process is simple and cost is reduced, whereas if air is trapped and adsorbed in the micro-pattern 630, there may be a problem in that adhesion is rather increased.

On the other hand, when the micropattern 630 is implemented using the nanophotosensitizer pattern 350 for reducing adhesion, the process is complicated and the cost is increased, whereas the adhesion between the substrate and the stencil 600 is caused by the micropattern 630 . This can certainly be reduced.

Therefore, the stencil 600 pattern and the micro-photosensitizer pattern 330 for reducing adhesion or the nano-sensitizer pattern 350 for reducing adhesion can be selectively used according to the user's needs, and in this embodiment, the nano-sensitizer pattern for reducing adhesion ( 350) will be selected and described.

Next, as shown in FIG. 7 , in the third step, a photoresist pattern 610 for a stencil is manufactured. (S300)

First, a photosensitizer is applied to the upper end of the nanophotosensitizer pattern 350 for reducing adhesion formed on the substrate 200 for the exposure process. In this case, the thickness of the photoresist is preferably within a range of 0.5 to 5 times the line width of the photoresist pattern 610 for a stencil to be implemented. If the ratio of the thickness to the line width of the photosensitive agent is less than 0.5, the thickness of the electroplating performed thereafter is formed too thin, so that the stencil 600 cannot be manufactured. This is because there is a problem in that the quality of the exposure pattern is deteriorated.

Here, the nano-photoresist pattern 350 for reducing adhesion is heat-treated through a reflow process, so that the solvent is all volatilized, so the performance as a photoresist is lost, and can only act as a pattern shape.

In this way, ultraviolet rays are irradiated from the back side of the substrate 200 for the exposure process to which the photosensitive agent is applied, and the photosensitive agent pattern 610 for a stencil is implemented through a developing process. That is, the photoresist pattern 610 for stencil is a state in which the photoresist pattern is implemented in the shape of the first chrome pattern 210 on the nano photoresist pattern 350 for reducing adhesion.

Next, as shown in FIG. 8 , the fourth step is a step of manufacturing a stencil. (S400)

A metal electropole plating process is performed on the photoresist pattern 610 for a stencil. The metal plating layer 620 is formed from the transparent electrode layer 220 . At this time, all metals capable of electroplating process such as nickel, nickel alloy, copper, and copper alloy can be used for plating. The reason for using the transparent electrode layer 220 as an electrode thin film in the first step (S100) is to use it as a seed layer for the plating process in the current step.

According to the above-described method, the stencil 600 in which the through hole 640 is formed in the shape of the first chrome pattern 210 and the fine pattern 630 is formed on the lower surface can be manufactured.

This stencil 600 can prevent the deterioration of the pattern quality due to the adhesion between the substrate and the stencil 600 by the micropattern 630 implemented on the lower surface, and the exposure process is performed by irradiating ultraviolet rays directly from the back side of the glass substrate. By doing so, a phenomenon in which a gap is generated between the chromium pattern of the photomask and the photosensitive agent can be prevented, thereby eliminating the pattern non-uniformity.

As described above, although the stencil for the printing process in which the fine pattern is formed and the manufacturing method thereof according to the embodiment of the present invention is shown according to the above description and drawings, this is merely an example and does not depart from the technical spirit of the present invention. It will be well understood by those skilled in the art that various changes and modifications can be made without departing from the scope of the present invention.

100a: 1a photomask
100b: 1b photomask
110: first chrome pattern
200: substrate for exposure process
210: first chrome pattern
220: transparent electrode layer
230: chrome layer
240: first photoresist pattern
300: second photo mask
310: second chrome pattern
320: second photoresist pattern
330: micro photosensitizer pattern for reducing adhesion
340: third photosensitizer pattern
350: nano photoresist pattern for reducing adhesion
400: substrate for phase mask production
500: phase mask
600: stencil
610: photoresist pattern for stencil
620: metal plating layer
630: fine pattern
640: through hole

Claims (8)

A through hole having a shape corresponding to the printed pattern is formed,
A stencil for a printing process with a fine pattern, characterized in that a fine pattern that reduces adhesion to the substrate is formed on the lower surface. The method for manufacturing a stencil for a printing process according to claim 1,
A first step of preparing a substrate for an exposure process in which a first chrome pattern corresponding to the printed pattern and a transparent electrode layer are laminated on an upper surface of a glass substrate;
a second step of manufacturing a photoresist pattern for reducing adhesion on the transparent electrode layer of the substrate for the exposure process;
a third step of manufacturing a photoresist pattern for a stencil using the photoresist pattern for reducing adhesion; and
A method of manufacturing a stencil for a printing process in which a fine pattern is formed, comprising: a fourth step of manufacturing a stencil using the photoresist pattern for the stencil. 3. The method of claim 2,
The first step of preparing the substrate for the exposure process is,
a step 1-1 (a) of forming a 1a photomask having a 1a chrome pattern formed thereon to correspond to the printed pattern on the upper surface of the glass substrate;
A method of manufacturing a stencil for a printing process having a fine pattern formed therein, characterized in that it comprises; step 1-2 (a) of forming a transparent electrode layer on the top surface of the first photomask. 3. The method of claim 2,
The first step of preparing the substrate for the exposure process is,
Step 1-1 (b) of sequentially forming a transparent electrode layer and a chromium layer on a glass substrate, and applying a photosensitizer on the chromium layer;
A 1b photomask having a first chrome pattern formed thereon to correspond to the printed pattern is placed on top of the photosensitizer of step 1-1 (b), and a first 1-2 photoresist pattern is formed through ultraviolet irradiation and developing process. (b) step;
Steps 1-3 (b) of forming a first chrome pattern by etching the chrome layer using the first photoresist pattern as a mask; 3. The method of claim 2,
The second step of producing the photosensitive agent pattern for reducing the adhesion is,
Step 2-1 (a) of forming a second photomask having a second chrome pattern formed thereon on a glass substrate;
a 2-2 (a) step of applying a photosensitive agent on the upper surface of the substrate for the exposure process, arranging the second photomask, and forming a second photosensitive agent pattern through ultraviolet irradiation and developing process;
A method of manufacturing a stencil for a printing process with a fine pattern, characterized in that it comprises a; step 2-3 (a) of heat-treating the second photoresist pattern to form a micro photoresist pattern for reducing adhesion. 3. The method of claim 2,
The second step of producing the photosensitive agent pattern for reducing the adhesion is,
Step 2-1 (b) of forming a second photomask having a second chrome pattern formed thereon on a glass substrate;
Step 2-2 (b) of arranging the second photomask on top of the substrate on which the photosensitive agent is applied, and manufacturing a substrate for producing a phase mask on which a second photosensitive agent pattern is formed through ultraviolet irradiation and developing process;
a step 2-3(b) of pouring and curing a transparent liquid polymer on the second photoresist pattern of the substrate for producing the phase mask, then separating it to prepare a phase mask;
a step 2-4 (b) of arranging the phase mask on top of the substrate for the exposure process to form a third photoresist pattern through ultraviolet irradiation and developing process;
Step 2-5 (b) of heat-treating the third photoresist pattern to form a nano photoresist pattern for reducing adhesion. 3. The method of claim 2,
The third step of producing the pattern for the stencil is,
a 3-1 step of applying a photosensitive agent to the upper end of the photosensitive agent pattern for reducing adhesion formed on the substrate for the exposure process;
A method for manufacturing a stencil for a printing process with a fine pattern, comprising: a step 3-2 of forming a photoresist pattern for a stencil through a developing process of irradiating ultraviolet rays on the lower surface of the substrate for the exposure process. 3. The method of claim 2,
The fourth step of manufacturing the stencil is,
A method for manufacturing a stencil for a printing process with a fine pattern, characterized in that the stencil is manufactured by performing a metal electroplating process on the photoresist pattern for the stencil to form a metal plating layer from the transparent electrode layer.

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