KR20150054400A - Mask for deposition and method of manufacturing the same - Google Patents

Abstract

A manufacturing method of a mask for deposition: forms a first metal layer which is made of a material different from a mask main body on a first side of the mask main body; forms a first photo resist pattern which exposes a second side partially on the second side of the mask main body; exposes the first metal layer partially by etching the mask main body through a first etching process based on the first photo resist pattern; and removes the first photo resist pattern. After that, the manufacturing method of the mask for deposition: forms a second metal layer which is made of a material different from the mask main body on an etched side of the mask main body; forms a second photo resist pattern which exposes the first metal layer partially on the first metal layer; and forms an opening of the mask for deposition by etching the first and second layers through a second etching process based on the second photo resist pattern; and removes the second photo resist pattern. The manufacturing method of the mask for deposition according to embodiments of the present invention can control the width and thickness of an opening precisely by performing a first etching process and a second etching process separately by using first and second metal layers which are made of a material having an etching selection ratio different from a mask main body.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a mask for vapor deposition,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a deposition mask, and more particularly, to a deposition mask used for depositing an organic emission layer of an organic light emitting display and a method of manufacturing the same.

Generally, in an organic light emitting diode display, an organic material (for example, an organic light emitting material) such as red (R), green (G), and blue (B) pixels is formed by using a fine metal mask (FMM) , A red light emitting material, a green light emitting material, and a blue light emitting material are individually vapor-deposited. These fine metal masks have openings patterned to correspond to each pixel.

The opening of the vapor deposition mask (for example, a fine metal mask) is formed by etching the mask body. At this time, since the shape of the photoresist pattern patterned on the upper and lower portions of the mask body and the etching time for the upper and lower portions of the mask body act as variables, it is difficult to control the thickness and width of the opening portion of the mask. Accordingly, the accuracy of deposition of the organic material on the pixels of the organic light emitting display device may be reduced.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of manufacturing an evaporation mask in which the width and height of an opening are precisely controlled.

Another object of the present invention is to provide an evacuation mask in which the width and height of the opening are precisely formed.

It is to be understood, however, that the scope of the present invention is not limited to the above-described embodiments, and may be variously modified without departing from the spirit and scope of the present invention.

According to another aspect of the present invention, there is provided a method for fabricating a mask for vapor deposition, including forming a first metal layer on the first surface of the mask body, the first metal layer being made of a material different from that of the mask body, Forming a first photoresist pattern partially exposing the second surface on a second surface, etching the mask body through a first etching process based on the first photoresist pattern to partially expose the first metal layer, And the first photoresist pattern can be removed. Thereafter, a second metal layer made of a material different from that of the mask body is formed on the etched surface of the mask body, a second photoresist pattern is formed on the first metal layer to partially expose the first metal layer, The first metal layer and the second metal layer may be etched through a second etching process based on the second photoresist pattern to form an opening of the deposition mask, and then the second photoresist pattern may be removed.

According to an embodiment, the opening may be formed in a part or all of a region where the first metal layer and the second metal layer are in contact with each other.

According to one embodiment, the width of the opening can be adjusted by the second photoresist pattern.

According to one embodiment, the mask body may be made of an iron-nickel alloy.

According to one embodiment, the first metal layer may be molybdenum (Mo), copper (Cu), titanium (Ti), or an alloy thereof.

According to one embodiment, the second metal layer may be molybdenum (Mo), copper (Cu), titanium (Ti), or an alloy thereof.

According to an embodiment, the first photoresist pattern and the second photoresist pattern may be formed by a photolithography process.

According to another aspect of the present invention, there is provided a vapor deposition mask including a mask body, a first metal layer disposed on a first surface of the mask body, the first metal layer being made of a material different from that of the mask body, A second metal layer disposed on a second surface of the mask body and made of a material different from that of the mask body, and an opening formed by etching the mask body, the first metal layer, and the second metal layer.

According to one embodiment, the mask body may be made of an iron-nickel alloy.

According to one embodiment, the first metal layer may be molybdenum (Mo), copper (Cu), titanium (Ti), or an alloy thereof.

According to one embodiment, the second metal layer may be molybdenum (Mo), copper (Cu), titanium (Ti), or an alloy thereof.

According to an embodiment, the first metal layer is formed on the first surface, the second metal layer is formed on the second surface with a first photoresist pattern partially exposing the second surface, The mask body may be formed in the etched region through a first etching process based on the photoresist pattern.

According to an embodiment, the first photoresist pattern may be removed after the first etching process.

According to an embodiment of the present invention, the opening may include a second photoresist pattern formed on the first metal layer to partially expose the first metal layer, and the second photoresist pattern may be formed on the first metal layer through a second etching process based on the second photoresist pattern. And then etching the metal layer and the second metal layer.

According to an embodiment, the second photoresist pattern may be removed after the second etching process.

According to an embodiment, the opening may be formed in a part or all of a region where the first metal layer and the second metal layer are in contact with each other.

According to one embodiment, the width of the opening can be adjusted by the second photoresist pattern.

According to an embodiment, the first photoresist pattern and the second photoresist pattern may be formed by a photolithography process.

The method for fabricating a deposition mask according to embodiments of the present invention includes performing a first etching process and a second etching process using a first metal layer and a second metal layer made of a material having an etch selectivity different from that of the mask body, Therefore, the width and thickness of the opening can be precisely controlled. In addition, since only the etching time of the second etching process acts as a variable in the process of forming the opening, it is easy to control the width and thickness of the opening by adjusting the etching time.

The deposition mask according to embodiments of the present invention may have an opening formed by precisely controlling the width and the thickness. As a result, by using the deposition mask in the process of depositing the organic light emitting layer of the organic light emitting device, the accuracy of deposition of the organic material (i.e., organic light emitting material) on the pixels of the organic light emitting device can be greatly improved.

It should be understood, however, that the effects of the present invention are not limited to the above-described effects, and may be variously modified without departing from the spirit and scope of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a flow chart showing a method of manufacturing a deposition mask according to embodiments of the present invention. Fig.
2A to 2G are cross-sectional views showing an example in which a vapor deposition mask is manufactured by the vapor deposition mask manufacturing method of FIG.
3 is a cross-sectional view illustrating a deposition mask according to embodiments of the present invention.
4A and 4B are views showing a mask substrate including the deposition mask of FIG.

For the embodiments of the invention disclosed herein, specific structural and functional descriptions are set forth for the purpose of describing an embodiment of the invention only, and it is to be understood that the embodiments of the invention may be practiced in various forms, The present invention should not be construed as limited to the embodiments described in Figs.

The present invention can be variously modified and may take various forms and should not be interpreted as being limited to specific embodiments.

The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms may be used for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between. Other expressions that describe the relationship between components, such as "between" and "between" or "neighboring to" and "directly adjacent to" should be interpreted as well.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprise", "having", and the like are intended to specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof, , Steps, operations, components, parts, or combinations thereof, as a matter of principle.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be construed as meaning consistent with meaning in the context of the relevant art and are not to be construed as ideal or overly formal in meaning unless expressly defined in the present application .

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals are used for the same constituent elements in the drawings and redundant explanations for the same constituent elements are omitted.

FIG. 1 is a flowchart showing a method of manufacturing a deposition mask according to an embodiment of the present invention, and FIGS. 2 (a) to 2 (g) are sectional views showing an example in which a deposition mask is manufactured by the method of manufacturing the deposition mask of FIG.

Referring to FIGS. 1 and 2A to 2G, the method for manufacturing a mask for vapor deposition of FIG. 1 includes forming a first metal layer made of a material different from the mask body on a first surface of a mask body (Step S110) After the first photoresist pattern is formed on two sides (Step S120), the first metal layer is partially exposed by etching the mask body in the first etching process based on the first photoresist pattern (Step S130) The resist pattern can be removed (step S140). 1, a second metal layer made of a material different from that of the mask body is formed on the etched surface of the mask body (Step S150), and a second photoresist pattern is formed on the first metal layer Step S160), the first metal layer and the second metal layer are etched through the second etching process to form the opening of the mask body (Step S170). 1, the second photoresist pattern may be removed (Step S180).

The deposition mask is used in the deposition process and is located between the substrate and the deposition source during the deposition process. Subsequently, a deposition material is deposited on the substrate through the deposition mask. For example, the vapor deposition mask includes a plurality of openings formed through the organic material, and the organic material is deposited on the substrate through the openings to form the organic light emitting layer of the organic light emitting device.

Specifically, FIGS. 2A to 2G show the process of forming the openings of the deposition mask by the method of manufacturing the deposition mask of FIG. However, for convenience of explanation, only one opening of the vapor deposition mask is shown in Figs. 2A to 2G.

2A, a first metal layer 120 made of a material different from that of the mask body 110 may be formed on the first surface 112 of the mask body 110 (Step S110). The mask body 110 may be made of a metal having high durability and strength. In one embodiment, the mask body 110 may be comprised of an iron-nickel (Fe-Ni) alloy. However, this is merely an example, and the material constituting the mask body 110 is not limited thereto. For example, the mask body 110 may include various metals such as nickel (Ni), aluminum (Al), and the like.

The first metal layer 120 may be formed entirely on the first side 112 of the mask body 110. For example, the first metal layer 120 may be deposited on the first side 112 of the mask body 110 to a desired thickness by a sputter process. The thickness of the opening of the deposition mask 100 may be controlled by the thickness of the first metal layer 120 deposited. The first metal layer 120 may be deposited to a thickness of several tens of angstroms. The metal included in the first metal layer 120 on the first surface 112 is a material different from the material constituting the mask body 110. In one embodiment, the first metal layer 120 may comprise molybdenum (Mo), copper (Cu), titanium (Ti), or alloys thereof. Thus, the mask body 110 and the first metal layer 120 have different etch selectivities. That is, when the mask body 110 is etched through an etchant or the like, the first metal layer 120 is not etched. On the contrary, when the first metal layer 120 is etched, 1 metal layer 120 is etched.

The first photoresist pattern 130 may be formed on the second surface 114 of the mask body 110 (Step S120) as shown in FIG. 2B. The first photoresist pattern 130 partially exposes the second surface 114. 2C, the mask body 110 may be etched through the first etching process based on the first photoresist pattern 130 to partially expose the first metal layer 120 (Step S130) have. The second surface 114 refers to the surface of the mask body 110 corresponding to the opposite surface of the first surface 112 of the mask body 110.

In one embodiment, the first photoresist pattern 130 may be formed by a photolithography process. The first etching process based on the first photoresist pattern 130 may etch only the mask body 110. The etchant used in the first etching process may include a ferric chloride etchant. The iron chloride etchant can etch the mask body 110 of the iron-nickel alloy, but does not affect metals such as molybdenum, copper, and titanium contained in the first metal layer 120. Thus, as shown in FIG. 2C, the mask body 110 may be etched by partially exposing the first metal layer 120 in a tapered manner by a first etching process. The area where the first metal layer 120 is exposed (i.e., denoted by A) and the taper angle can be controlled by the etching time of the first etching process.

The first photoresist pattern is removed (Step S140) and the second metal layer 140 is formed on the etched surface of the mask body 110 as a whole (Step S150), as shown in FIGS. 2D and 2E .

The second metal layer 140 is made of a material different from that of the mask body 110. In one embodiment, the second metal layer 140 may comprise molybdenum, copper, titanium, or alloys thereof. Thus, the mask body 110 and the second metal layer 140 have different etch selectivities. That is, when the mask body 110 is etched through an etching agent or the like, the second metal layer 140 is not etched. On the contrary, when the second metal layer 140 is etched, 140 are etched.

A region in which the first metal layer 120 and the second metal layer 140 are directly in contact (that is, indicated by B) may exist in the region where the first metal layer 120 is exposed. The second metal layer 140 may be formed by supporting the first metal layer 120 under the first metal layer 120 so that portions other than the desired opening width are not lost in the opening forming process subsequent to the first metal layer 120 having a small thickness. As a support for

2F and 2G, a second photoresist pattern 150 is formed on the first metal layer 120 to partially expose the first metal layer 120 (Step S160) The first metal layer 120 and the second metal layer 140 are etched through the second etching process based on the resist pattern 150 so that the opening 160 of the deposition mask 100 is formed (Step S170).

In one embodiment, the second photoresist pattern 150 may be formed by a photolithography process. The first metal layer 120 exposed by the second photoresist pattern 150 and the second metal layer 140 contacting the first metal layer 120 may be etched by a second etching process. In one embodiment, the first metal layer 120 and the second metal layer 140 may comprise molybdenum, copper, titanium, or alloys thereof. The first metal layer 120 and the second metal layer 140 may be formed of the same material or different materials. In the case where the first metal layer 120 and the second metal layer 140 are made of the same metal material, the second etching process can form the opening portion 160 of the deposition mask 100 using one kind of etching agent have. For example, when the first metal layer 120 and the second metal layer 140 are formed of titanium, the second etching process may form the opening 160 using a fluoric acid etchant. When the first metal layer 120 is made of titanium and the second metal layer 140 is made of molybdenum, the second etching process includes a process of etching the first metal layer 120 using a fluoric acid etchant, The opening 160 may be formed by etching the second metal layer 140 using an etchant composed of the compound.

As the width of the opening 160 (that is, indicated by C) is narrower, the deposition accuracy of the organic material deposited on the substrate through the deposition mask 100 increases. In one embodiment, the width C of the opening 160 may be adjusted by the second photoresist pattern 150. [ The width C of the opening 160 can be adjusted by adjusting the width of the first metal layer 120 exposed by the second photoresist pattern 150. [

The deposition mask may be in the final shape by removing the second photoresist pattern (Step S180).

1 includes a first metal layer 120 and a second metal layer 140 which are made of a material having an etch selectivity different from that of the mask body 110 to form the opening 160 The width and thickness of the opening 160 can be precisely controlled. In addition, when forming the opening 160, only the etching time of the second etching process acts as a variable. Therefore, it is easy to control the width and the thickness of the opening through the adjustment of the etching time.

3 is a cross-sectional view illustrating a deposition mask according to embodiments of the present invention.

Referring to FIG. 3, the deposition mask 100 may include a mask body 110, a first metal layer 120, a second metal layer 140, and an opening 165.

The mask body 110 may be made of a metal having high durability and strength. In one embodiment, the mask body 110 may be comprised of an iron-nickel alloy. However, this is an example, and the material constituting the mask body 110 is not limited thereto.

The first metal layer 120 is disposed on the first surface 112 of the mask body 110 and may be formed of a material different from that of the mask body 110. In one embodiment, the first metal layer 120 may comprise molybdenum, copper, titanium, or alloys thereof. Thus, the mask body 110 and the first metal layer 120 have different etch selectivities. The thickness of the opening 165 of the deposition mask 100 may be controlled by the thickness of the first metal layer 120 deposited. The first metal layer 120 may be deposited to a thickness of several tens of angstroms.

The second metal layer 140 is disposed on the second surface of the mask body 110 and may be made of a material different from that of the mask body 110. In one embodiment, the second metal layer 140 may comprise molybdenum, copper, titanium, or alloys thereof. Thus, the mask body 110 and the first metal layer 120 have different etch selectivities. The second metal layer 140 may be formed on the second surface 110 of the mask body 110 etched by the first photoresist pattern by sputtering or the like. Here, the second surface 114 refers to the surface of the mask body 110 corresponding to the opposite surface of the first surface 112 of the mask body 110. In one embodiment, the second metal layer 140 is formed by forming a first photoresist pattern partially exposing the second surface 114, and etching the mask body (not shown) through a first etching process based on the first photoresist pattern 110 may be formed in the etched area. A region where the first metal layer 120 and the second metal layer 140 are in contact may occur and a region where the first metal layer 120 and the second metal layer 140 are in contact may be formed by a second etching process The openings 165 may be formed by removing all or a part of the openings 165. In one embodiment, the first photoresist pattern may be removed after a first etch process, such as through a lift off or ashing process. The second metal layer 140 serves as a support for supporting the first metal layer 120 under the first metal layer 120 so that the first metal layer 120 having a small thickness is not lost in the subsequent process of forming the openings 165 can do.

The opening 165 may be formed in a part or all of a region where the first metal layer 120 and the second metal layer 140 are in contact with each other. The opening 165 serves to deposit the deposition material discharged from the deposition source in a predetermined region on the substrate during the deposition process. For example, in the step of forming the organic light emitting layer of the organic light emitting display, the organic light emitting materials passing through the opening 165 of the vapor deposition mask 100 may be deposited in the pixel region of the organic light emitting device. The opening 165 is formed by forming a second photoresist pattern partially exposing the first metal layer on the first metal layer and etching the first metal layer and the second metal layer through a second etching process based on the second photoresist pattern, And may be formed by etching a metal layer.

In one embodiment, the width C of the opening 165 may be adjusted by the second photoresist pattern. Further, the first photoresist pattern and the second photoresist pattern are formed by a photolithography process, and are removed after the first etching process and the second etching process, respectively. However, since the process of manufacturing the vapor deposition mask 100 has been described above, a duplicate description thereof will be omitted.

As described above, the deposition mask 100 includes a first metal layer 120 and a second metal layer 140 made of a material having a different etch selectivity from the mask body 110, thereby precisely controlling the width and thickness (Not shown). Further, when forming the openings 165, the width C of the openings and the thickness of the openings can be easily adjusted by adjusting the etching time. Therefore, when depositing the organic light emitting layer in the pixel region of the organic light emitting display device using the deposition mask 100, the accuracy of the deposition process can be improved.

4A and 4B are views showing a mask substrate including the deposition mask of FIG.

Referring to FIG. 4A, the mask substrate 400 may include at least one vapor deposition mask 420. Although FIG. 4A shows that 12 evaporation masks 420 are formed on the mask substrate 400, this is an illustrative example, and the number and arrangement of the evaporation masks 420 are not limited thereto.

Referring to FIG. 4B, each deposition mask 420 may include a shield 480 and a plurality of openings 460 patterned. Each of the deposition masks 420 may include first and second metal layers made of a material different from that of the mask body and the mask body. Therefore, since the upper and lower surfaces (i.e., the first surface and the second surface) of the mask body can be independently etched, the thickness and width of the opening 460 of each evaporation mask 420 can be precisely adjusted . The deposition mask 420 including the plurality of openings 460 and the method of manufacturing the same are described above with reference to FIGS. 1 to 3, and a duplicate description thereof will be omitted.

As described above, organic materials (i.e., organic light emitting materials) are deposited on the pixels constituting the organic light emitting display. The organic light emitting materials may be deposited (or patterned) on the pixels according to the pattern of the openings 460 of the evaporation mask 420 by an evaporation process or the like. At this time, since the organic materials to be deposited are different for each pixel emitting light of different colors, precise deposition is required. The deposition mask 420 according to embodiments of the present invention may have openings 460 that are precisely controlled in width and thickness by including first and second metal layers made of a material different from the mask body. Therefore, by using the mask substrate 400 including the deposition mask 420 in the organic material deposition process, the accuracy of deposition of the organic material on the pixels of the organic light emitting device can be greatly improved.

The present invention can be applied variously to an evaporation mask. For example, the present invention can be applied to an evaporation mask for individually depositing organic materials (i.e., a red light emitting material, a green light emitting material, and a blue light emitting material) in red, green, and blue pixels in an organic light emitting diode display.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the following claims. It can be understood that it is possible.

100: vapor deposition mask 110: mask body
112: first side 114: second side
120: first metal layer 140: second metal layer
160, 165: opening

Claims (18)

Forming a first metal layer made of a material different from that of the mask body on a first surface of the mask body;
Forming a first photoresist pattern partially exposing the second surface on a second surface of the mask body;
Etching the mask body through a first etching process based on the first photoresist pattern to partially expose the first metal layer;
Removing the first photoresist pattern;
Forming a second metal layer made of a material different from that of the mask body on an etched surface of the mask body;
Forming a second photoresist pattern partially exposing the first metal layer on the first metal layer;
Etching the first metal layer and the second metal layer through a second etching process based on the second photoresist pattern to form an opening of the deposition mask; And
And removing the second photoresist pattern. The method according to claim 1, wherein the opening is formed in a part or all of a region where the first metal layer and the second metal layer are in contact with each other. 3. The method of claim 2, wherein the width of the opening is controlled by the second photoresist pattern. The method of claim 1, wherein the mask body is an iron-nickel (Fe-Ni) alloy. The method of claim 4, wherein the first metal layer is molybdenum (Mo), copper (Cu), titanium (Ti), or an alloy thereof. The method of claim 4, wherein the second metal layer is molybdenum (Mo), copper (Cu), titanium (Ti), or an alloy thereof. The method of claim 1, wherein the first photoresist pattern and the second photoresist pattern are formed by a photolithography process. A mask body;
A first metal layer disposed on a first surface of the mask body, the first metal layer being made of a material different from that of the mask body;
A second metal layer disposed on a second surface of the mask body, the second metal layer being made of a material different from that of the mask body; And
And an opening formed by etching the mask body, the first metal layer, and the second metal layer. The mask according to claim 8, wherein the mask body is an iron-nickel alloy. 10. The mask according to claim 9, wherein the first metal layer is molybdenum (Mo), copper (Cu), titanium (Ti), or an alloy thereof. 10. The mask according to claim 9, wherein the second metal layer is molybdenum (Mo), copper (Cu), titanium (Ti), or an alloy thereof. 9. The method of claim 8,
Wherein the first metal layer is formed on the first surface,
The second metal layer may include a first photoresist pattern formed on the second surface to partially expose the second surface, and a second photoresist pattern may be formed on the second surface of the second metal layer through a first etching process based on the first photoresist pattern, Wherein the mask is formed on the substrate. 13. The mask according to claim 12, wherein the first photoresist pattern is removed after the first etching process. 13. The method of claim 12, wherein the opening is formed with a second photoresist pattern partially exposing the first metal layer on the first metal layer, and the second photoresist pattern is formed on the first metal layer through a second etching process based on the second photoresist pattern. Wherein the metal layer and the second metal layer are formed by etching. 15. The mask according to claim 14, wherein the second photoresist pattern is removed after the second etching process. 15. The mask according to claim 14, wherein the opening is formed in a part or all of a region where the first metal layer and the second metal layer are in contact with each other. 17. The mask according to claim 16, wherein the width of the opening is adjusted by the second photoresist pattern. 18. The mask according to claim 17, wherein the first photoresist pattern and the second photoresist pattern are formed by a photolithography process.

Images