阅读说明：本技术 掩模支撑模板及其制造方法、掩模制造方法及框架一体型掩模的制造方法 (Mask supporting template, method for manufacturing mask, and method for manufacturing frame-integrated mask ) 是由 李炳一 金奉辰 李裕进 于 2021-03-31 设计创作，主要内容包括：本发明涉及掩模支撑模板及其制造方法、掩模制造方法及框架一体型掩模的制造方法。根据本发明的掩模支撑模板的制造方法,包括以下步骤：(a)准备一面形成有第一绝缘部的掩模金属膜；(b)通过在模板上夹设第一绝缘部使掩模金属膜粘合到模板的上部面；(c)通过在掩模金属膜上形成掩模图案来制造掩模。(The invention relates to a mask supporting template and a manufacturing method thereof, a mask manufacturing method and a manufacturing method of a frame integrated mask. The method for manufacturing the mask supporting template according to the present invention comprises the steps of: (a) preparing a mask metal film having a first insulating portion formed on one surface thereof; (b) bonding a mask metal film to an upper surface of the stencil by sandwiching a first insulating portion on the stencil; (c) the mask is manufactured by forming a mask pattern on the mask metal film.)

1. A method of manufacturing a mask support stencil, comprising the steps of:

(a) preparing a mask metal film having a first insulating portion formed on one surface thereof;

(b) bonding a mask metal film to an upper surface of the stencil by sandwiching a first insulating portion on the stencil;

(c) the mask is manufactured by forming a mask pattern on the mask metal film.

2. The method of manufacturing a mask support template according to claim 1,

a temporary bonding portion is formed on an upper surface of the template, and the mask metal film is bonded to the upper surface of the template with the temporary bonding portion and the first insulating portion interposed therebetween.

3. The method of manufacturing a mask support template according to claim 1,

the first insulating portion includes at least one of a cured negative photoresist, a negative photoresist containing an epoxy resin.

4. The method of manufacturing a mask support template according to claim 1,

the temporary bonding portion is an adhesive or an adhesive sheet that can be separated by heating, or an adhesive sheet that can be separated by irradiation with ultraviolet rays.

5. The method of manufacturing a mask support template of claim 1, wherein step (c) comprises the steps of:

(c1) forming a patterned second insulating portion on the mask metal film;

(c2) etching the exposed portions of the mask metal film between the second insulating portions and forming a mask pattern; and

(c3) and removing the second insulating part.

6. The method of manufacturing a mask support template of claim 1, wherein step (c) comprises the steps of:

(c1) forming a patterned 2 nd-1 st insulating portion on the mask metal film;

(c2) forming a first mask pattern of a predetermined depth on one side of the mask metal film by wet etching;

(c3) filling a2 nd-2 nd insulating portion at least in the first mask pattern;

(c4) volatilizing at least a portion of the 2 nd-2 nd insulating portion by baking;

(c5) exposing the upper part of the 2 nd-1 st insulating part and only leaving the 2 nd-2 nd insulating part positioned at the vertical lower part of the 2 nd-1 st insulating part; and

(c6) wet etching is performed on one surface of the mask metal film to form a second mask pattern penetrating the other surface of the mask metal film from the first mask pattern.

7. The method of manufacturing a mask support template according to claim 6,

the first mask pattern has a thickness greater than that of the second mask pattern, and a width greater than that of the second mask pattern.

8. The method of manufacturing a mask support template according to claim 6,

the sum of the shapes of the first mask pattern and the second mask pattern as a whole exhibits a tapered shape or an inverted tapered shape.

9. The method of manufacturing a mask supporting template according to claim 6, wherein between steps (c2) and (c3) further comprising the steps of:

(1) forming 2-3 insulation parts on at least a portion of the first mask pattern exposed between the 2-1 insulation parts;

(2) reducing an angle formed by a side of the first mask pattern with a horizontal plane by further wet etching the first mask pattern;

(3) removing the 2 nd-3 rd insulation part.

10. The method of manufacturing a mask support template of claim 9,

in the step (2), the side of the first mask pattern forms an angle of 30 ° to 70 ° with the horizontal plane.

11. A mask holding stencil for holding a mask for forming an OLED pixel and for aligning the mask to a frame, the mask holding stencil comprising:

a template, the upper surface of which is formed with a temporary bonding part; and

a mask having a mask pattern formed thereon and a first insulating portion formed on one surface thereof,

the template and the mask are bonded by interposing a temporary bonding portion and a first insulating portion.

12. The mask support template of claim 11,

the mask is bonded to the stencil in a state where a tensile force in the side direction is applied.

13. A mask manufacturing method comprising the steps of:

(a) preparing a mask metal film having a first insulating portion formed on one surface thereof;

(b) bonding a mask metal film to an upper surface of the stencil by sandwiching a first insulating portion on the stencil;

(c) manufacturing a mask by forming a mask pattern on the mask metal film;

(d) the template and mask are separated.

14. A method for manufacturing a frame-integrated mask integrally formed of at least one mask and a frame for supporting the mask, wherein the method comprises the steps of:

(a) preparing a mask metal film having a first insulating portion formed on one surface thereof;

(b) bonding a mask metal film to an upper surface of the stencil by sandwiching a first insulating portion on the stencil;

(c) manufacturing a mask by forming a mask pattern on the mask metal film;

(d) loading a stencil onto a frame having at least one mask unit region so that the mask corresponds to the mask unit region of the frame; and

(e) the mask is attached to the frame.

15. The method of manufacturing a frame-integrated mask according to claim 14, wherein,

further comprising the step of removing the first insulating portion on the mask after the step (e).

16. The method of manufacturing a frame-integrated mask according to claim 15, wherein,

the first insulating portion is removed by applying at least one of plasma and ultraviolet rays.

17. The method of manufacturing a frame-integrated mask according to claim 14, wherein,

in the step (e), the mask is attached to the frame by irradiating laser to the first welding parts disposed on the four sides of the mask.

18. The method of manufacturing a frame-integrated mask according to claim 17, wherein,

second welding parts are further arranged at the vertex parts of the four sides of the dummy area of the mask, and the arrangement interval of the second welding parts is smaller than that of the first welding parts,

in the step (b), the mask is attached to the frame by irradiating the first welding portion and the second welding portion with laser.

19. The method of manufacturing a frame-integrated mask according to claim 17, wherein,

second welding parts are further arranged in vertex parts of four sides of the dummy area of the mask, and the number of the second welding parts arranged in a unit area is larger than that of the first welding parts,

in the step (b), the mask is attached to the frame by irradiating the first welding portion and the second welding portion with laser.

20. The method of manufacturing a frame-integrated mask according to claim 17, wherein,

the mask is bonded to the stencil in a state where a tensile force in the side direction is applied.

21. The method of manufacturing a frame-integrated mask according to claim 20,

after the step (b), separating the mask from the template by any one of heating, chemical treatment, ultrasonic wave application, and ultraviolet ray application to the temporary bonding portion,

if the stencil is separated from the mask, a tensile force applied to the mask is applied to the frame.

22. A method for manufacturing a frame-integrated mask integrally formed of at least one mask and a frame for supporting the mask, wherein the method comprises the steps of:

(a) loading the template of claim 11 onto a frame having at least one mask cell area such that the mask corresponds to the mask cell area of the frame; and

(b) the mask is attached to the frame.

Technical Field

The invention relates to a mask supporting template and a manufacturing method thereof, a mask manufacturing method and a manufacturing method of a frame integrated mask. And more particularly, to a mask supporting template capable of accurately controlling the size and position of a mask pattern, a method of manufacturing the same, a method of manufacturing a mask, and a method of manufacturing a frame-integrated mask.

Background

As a technique for forming pixels in an OLED (organic light emitting diode) manufacturing process, an FMM (Fine Metal Mask) method is mainly used, which attaches a Metal Mask (Shadow Mask) in the form of a thin film to a substrate and deposits an organic substance at a desired position.

The conventional mask manufacturing method prepares a metal thin plate used as a mask, performs PR coating on the metal thin plate and then performs patterning or performs PR coating to have a pattern and then manufactures the mask having the pattern by etching. However, in order to prevent the Shadow Effect (Shadow Effect), it is difficult to obliquely Taper the mask pattern (Taper), and an additional process needs to be performed, thereby causing an increase in process time and cost, and a decrease in productivity.

In the super-resolution OLED, the conventional QHD resolution is 500-600PPI (pixel per inch), the pixel size reaches about 30-50 μm, and the resolution of-860 PPI, -1600PPI is higher than that of the 4K UHD and 8K UHD resolution. Therefore, it is urgently required to develop a technique capable of precisely adjusting the size of the mask pattern.

In addition, in the existing OLED manufacturing process, after the mask is manufactured in a bar shape, a plate shape, or the like, the mask is solder-fixed to the OLED pixel deposition frame and used. One mask may have a plurality of cells corresponding to one display. In addition, in order to manufacture a large-area OLED, a plurality of masks may be fixed to an OLED pixel deposition frame, and each mask is stretched to be flat in the process of being fixed to the frame. Adjusting the tensile force to flatten the entire portion of the mask is a very difficult task. In particular, in order to align a mask pattern having a size of several to several tens μm while planarizing each cell, the following high-difficulty work is required: the alignment state is checked in real time while finely adjusting the tensile force applied to each side of the mask.

However, in the process of fixing a plurality of masks to one frame, there is a problem that alignment between the masks and between the mask units is not good. In addition, in the process of welding and fixing the mask to the frame, the mask film has a problem that the mask is sagged or distorted due to a load because the thickness of the mask film is too thin and the area of the mask film is large; a problem of misalignment of the mask unit due to wrinkles, burrs (burr), etc. generated at the welded portion during the welding process, etc.

In this way, in consideration of the pixel size of the ultra-high quality OLED, it is necessary to reduce the alignment error between the respective units to about several μm, and exceeding this error causes product defects, so the yield may be extremely low. Therefore, it is necessary to develop a technique capable of preventing deformation such as sagging or twisting of the mask and making alignment accurate, a technique of fixing the mask to the frame, and the like.

Disclosure of Invention

Technical problem

Accordingly, the present invention has been made to solve the above-mentioned various problems of the related art, and an object of the present invention is to provide a mask supporting template and a method of manufacturing the same, a mask manufacturing method, and a method of manufacturing a frame-integrated mask, which are capable of accurately controlling the size of a mask pattern.

Another object of the present invention is to provide a method for manufacturing a frame-integrated mask, which can prevent deformation such as wrinkles or twists from occurring in the mask.

Technical scheme

The above object of the present invention is achieved by a method for manufacturing a mask supporting template, comprising the steps of: (a) preparing a mask metal film having a first insulating portion formed on one surface thereof; (b) bonding a mask metal film to an upper surface of the stencil by sandwiching a first insulating portion on the stencil; (c) the mask is manufactured by forming a mask pattern on the mask metal film.

The temporary bonding portion is formed on an upper surface of the template, and the mask metal film may be bonded to the upper surface of the template by interposing the temporary bonding portion and the first insulating portion.

The first insulating portion may include at least one of a cured negative photoresist, a negative photoresist containing an epoxy resin.

The temporary bonding portion may be an adhesive or an adhesive sheet which can be separated by heating and an adhesive or an adhesive sheet which can be separated by irradiation with ultraviolet rays.

Step (c) may comprise the steps of: (c1) forming a patterned second insulating portion on the mask metal film; (c2) etching the exposed portions of the mask metal film between the second insulating portions and forming a mask pattern; and (c3) removing the second insulation.

Step (c) may comprise the steps of: (c1) forming a patterned 2 nd-1 st insulating portion on the mask metal film; (c2) forming a first mask pattern of a predetermined depth on one side of the mask metal film by wet etching; (c3) filling a2 nd-2 nd insulating portion at least in the first mask pattern; (c4) volatilizing at least a portion of the 2 nd-2 nd insulating portion by baking; (c5) exposing the upper part of the 2 nd-1 st insulating part and only leaving the 2 nd-2 nd insulating part positioned at the vertical lower part of the 2 nd-1 st insulating part; and (c6) performing wet etching on one side of the mask metal film to form a second mask pattern penetrating the other side of the mask metal film from the first mask pattern.

The thickness of the first mask pattern may be greater than that of the second mask pattern, and the width of the first mask pattern may be greater than that of the second mask pattern.

The sum of the shapes of the first mask pattern and the second mask pattern may be tapered or reverse tapered as a whole.

The following steps may be further included between the step (c2) and the step (c 3): (1) forming 2-3 insulation parts on at least a portion of the first mask pattern exposed between the 2-1 insulation parts; (2) reducing an angle formed by a side of the first mask pattern with a horizontal plane by further wet etching the first mask pattern; (3) removing the 2 nd-3 rd insulation part.

In the step (2), the side of the first mask pattern may form an angle of 30 ° to 70 ° with a horizontal plane.

Further, the above object of the present invention can be achieved by a mask supporting stencil for supporting a mask for OLED pixel formation and corresponding the mask to a frame, the mask supporting stencil comprising: a template, the upper surface of which is formed with a temporary bonding part; and a mask having a mask pattern formed thereon and having a first insulating portion formed on one surface thereof, the template and the mask being bonded by interposing the temporary bonding portion and the first insulating portion therebetween.

The mask may be bonded to the stencil in a state where a tensile force in a lateral direction is applied.

The above object of the present invention is achieved by a mask manufacturing method, comprising the steps of: (a) preparing a mask metal film having a first insulating portion formed on one surface thereof; (b) bonding a mask metal film to an upper surface of the stencil by sandwiching a first insulating portion on the stencil; (c) manufacturing a mask by forming a mask pattern on the mask metal film; (d) the template and mask are separated.

Further, the above object of the present invention is achieved by a method for manufacturing a frame-integrated mask integrally formed of at least one mask and a frame for supporting the mask, wherein the method comprises the steps of: (a) preparing a mask metal film having a first insulating portion formed on one surface thereof; (b) bonding a mask metal film to an upper surface of the stencil by sandwiching a first insulating portion on the stencil; (c) manufacturing a mask by forming a mask pattern on the mask metal film; (d) loading a stencil onto a frame having at least one mask unit region so that the mask corresponds to the mask unit region of the frame; and (e) attaching the mask to the frame.

The step (e) may be followed by a step of removing the first insulating portion on the mask.

The first insulating portion may be removed by applying at least one of plasma, ultraviolet rays.

In the step (e), the mask may be attached to the frame by irradiating laser to the first welding parts disposed at the four sides of the mask.

The second welding parts may be further arranged at the vertex portions of the four sides of the dummy area of the mask at an arrangement interval smaller than that of the first welding parts, and the mask may be attached to the frame by irradiating the laser to the first welding parts and the second welding parts in step (b).

The mask may be attached to the frame by irradiating the first welding part and the second welding part with laser in the step (b).

The mask may be bonded to the stencil in a state where a tensile force in a lateral direction is applied.

After the step (b), the temporary bonding portion is subjected to any one of heating, chemical treatment, application of ultrasonic waves, and application of ultraviolet rays to separate the mask from the template, and if the template is separated from the mask, a tensile force applied to the mask is applied to the frame.

Further, the above object of the present invention is achieved by a method for manufacturing a frame-integrated mask integrally formed of at least one mask and a frame for supporting the mask, the method including the steps of: (a) loading the template onto a frame having at least one mask unit region such that the mask corresponds to the mask unit region of the frame; and (b) attaching the mask to the frame.

Advantageous effects

According to the present invention as described above, there is an effect that the size and position of the mask pattern can be precisely controlled.

In addition, according to the present invention, the mask can be prevented from being deformed such as wrinkles and twists.

Drawings

Fig. 1 is a schematic view of a conventional process of attaching a mask to a frame.

Fig. 2 is a front view and a side sectional view of a frame-integrated mask according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of a mask according to an embodiment of the invention.

Fig. 4 to 5 are schematic views of a process of forming a mask by bonding a mask metal film on a template to manufacture a mask supporting template according to an embodiment of the present invention.

Fig. 6 is a schematic view of an etching degree of a mask according to a conventional mask manufacturing process and a comparative example.

Fig. 7 to 8 are schematic views of a manufacturing process of a mask according to an embodiment of the present invention.

Fig. 9 is a schematic diagram of the degree of etching of a mask according to an embodiment of the present invention.

Fig. 10 is a schematic view of a process of manufacturing a mask support template according to an embodiment of the present invention.

FIG. 11 is a schematic diagram of a mask etch profile according to a comparative example and an embodiment of the present invention.

Fig. 12 is a schematic view of a state in which a template is loaded on a frame so that a mask corresponds to a unit region of the frame according to an embodiment of the present invention.

Fig. 13 is a schematic view of a process of separating the mask and the template after attaching the mask to the frame according to an embodiment of the present invention.

Fig. 14 is a schematic view of a state in which a mask is attached to a cell region of a frame and an insulating portion is removed, according to an embodiment of the present invention.

Fig. 15 is a schematic view of a mask according to another embodiment of the present invention.

Fig. 16 is a schematic view of a process of loading a template onto a frame so that a mask corresponds to and is attached to a unit region of the frame according to another embodiment of the present invention.

Reference numerals:

23: first insulating part

25: second insulating part

50: stencil (template)

51: laser passing hole

55: temporary bonding part

100: mask and method for manufacturing the same

110: masking metal film

200: frame structure

210: edge frame section

220: mask unit sheet part

221: edge sheet part

223: first grid sheet part

225: second grid sheet part

C: cell and mask cell

CR: mask unit region

DM: dummy part and mask dummy part

L: laser

M1, M2, M3: 2 nd-1 st, 2 nd-2 nd, 2 nd-3 rd insulation parts

M2': 2 nd-2 nd insulating part left after exposure

P: mask pattern

P1, P1-1, P1-2: first mask pattern

P2, P2-1, P2-2: second mask pattern

WB: welding bead

WE1, WE2, WE 3: wet etching

WP, WP1, WP 2: weld part

Detailed Description

The following detailed description of the invention refers to the accompanying drawings that illustrate specific embodiments in which the invention may be practiced. These embodiments are described in detail below in order to enable those skilled in the art to practice the invention. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. The various embodiments of the invention should be understood as distinct and not mutually exclusive. For example, the particular shapes, structures and characteristics described herein may enable one embodiment to be implemented within other embodiments without departing from the spirit and scope of the present invention. In addition, the location or arrangement of individual elements within each disclosed embodiment should be understood as being modified without departing from the spirit and scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled. In the drawings, like numerals refer to the same or similar functions throughout the several views, and the length, area, thickness, etc. and forms thereof may be exaggerated for convenience.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings in order to enable those skilled in the art to easily practice the invention.

Fig. 1 is a schematic view of a conventional process of attaching a mask 10 to a frame 20.

The conventional mask 10 is a stripe Type (Stick-Type) or a Plate Type (Plate-Type), and the stripe Type mask 10 of fig. 1 may be used by solder-fixing both sides of a stripe to an OLED pixel deposition frame. The mask 10 has a plurality of display cells C in its Body (Body, or mask film 11). One cell C corresponds to one display of the smartphone or the like. The cell C has a pixel pattern P formed therein so as to correspond to each pixel of the display.

Referring to fig. 1(a), a tensile force F1 to F2 is applied along the longitudinal direction of the strip mask 10, and the strip mask 10 is mounted on the frame 20 having a box shape in an expanded state. The cells C1-C6 of the strip-type mask 10 are located in the blank area inside the frame 20.

Referring to fig. 1 (b), the tensile forces F1 to F2 applied to the respective sides of the bar-shaped mask 10 are finely adjusted while performing alignment, and then the bar-shaped mask 10 and the frame 20 are connected to each other by welding a portion of the side of the W-bar-shaped mask 10. Fig. 1 (c) shows a side cross section of the bar type mask 10 and the frame connected to each other.

Although the tensile forces F1 to F2 applied to the sides of the strip type mask 10 are finely adjusted, a problem of poor alignment of the mask cells C1 to C3 with respect to each other still occurs. For example, the distances between the patterns P of the cells C1-C6 are different from each other or the patterns P are skewed. Since the stripe type mask 10 has a large area including the plurality of cells C1-C6 and has a very thin thickness of several tens of μm, it is easily sagged or distorted by a load. It is very difficult to confirm the alignment state of the cells C1 to C6 in real time by a microscope while adjusting the tensile forces F1 to F2 to flatten all the cells C1 to C6. However, in order to prevent the mask pattern P having a size of several μm to several tens μm from adversely affecting the pixel process of the ultra high quality OLED, the alignment error is preferably not greater than 3 μm. The alignment error between such adjacent cells is referred to as Pixel Position Accuracy (PPA).

Further, it is very difficult to precisely align the plurality of bar masks 10 and the plurality of cells C1 to C6 of the bar mask 10 while connecting the bar masks 10 to one frame 20, respectively, and it is only necessary to increase the process time for alignment, thereby reducing the production efficiency.

In addition, after the bar type mask 10 is coupled and fixed to the frame 20, the tensile force F1-F2 applied to the bar type mask 10 is reversely applied to the frame 20. This tension causes a slight deformation of the frame 20 and a problem of distortion of the alignment state among the plurality of cells C-C6 occurs.

In view of this, the present invention provides a frame 200 and a frame-integrated mask, which can form an integrated structure of a mask 100 and a frame 200. The mask 100 integrated with the frame 200 may not only prevent deformation such as sagging or twisting, but also be accurately aligned with the frame 200.

Fig. 2 is a front view ((a) of fig. 2) and a side sectional view ((b) of fig. 2) of a frame-integrated mask according to an embodiment of the present invention.

Hereinafter, although the present specification describes the arrangement of the frame-integrated mask, the structure and the manufacturing process of the frame-integrated mask may be understood to include the entire contents of korean patent application No. 2018-0016186.

Referring to fig. 2, the frame integrated mask may include a plurality of masks 100 and a frame 200. In other words, the plurality of masks 100 are attached to the frame 200. For convenience of explanation, the mask 100 having a rectangular shape will be described as an example, but the mask 100 may have a bar-shaped mask shape having protrusions for sandwiching both sides before being attached to the frame 200, and the protrusions may be removed after being attached to the frame 200.

Each mask 100 is formed with a plurality of mask patterns P, and one mask 100 may be formed with one cell C. One mask unit C may correspond to one display of a smartphone or the like.

The mask 100 may be made of invar (invar), super invar (super invar), nickel (Ni), nickel-cobalt (Ni-Co), or the like. The mask 100 may use a sheet metal (sheet) generated by a rolling process or electroforming.

The frame 200 may be formed in a form of attaching a plurality of masks 100. The frame 200 is preferably formed of invar, super invar, nickel-cobalt, etc. having the same thermal expansion coefficient as the mask in consideration of thermal deformation. The frame 200 may include an edge frame portion 210 that is generally square, box-shaped. The interior of the edge frame portion 210 may be hollow in shape.

In addition, the frame 200 has a plurality of mask unit regions CR, and may include a mask unit sheet part 220 connected to the edge frame part 210. The mask unit sheet portion 220 may be composed of an edge sheet portion 221, and first and second grid sheet portions 223 and 225. The edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 are portions divided on the same sheet, and are integrated with each other.

The thickness of the edge frame part 210 may be greater than that of the mask unit sheet part 220, and may be formed in a thickness of several mm to several cm. The thickness of the mask die section 220, although thinner than the thickness of the edge frame section 210, is thicker than the mask 100, and may be about 0.1mm to 1 mm. The width of the first and second grid sheet portions 223, 225 may be about 1-5 mm.

In the planar sheet, a plurality of mask unit regions CR (CR11 to CR56) may be provided in addition to the regions occupied by the edge sheet portion 221 and the first and second grid sheet portions 223, 225.

The mask 200 has a plurality of mask cell regions CR, and the masks 100 are attached so that the mask cells C correspond to the mask cell regions CR, respectively. The mask unit C corresponds to the mask unit region CR of the frame 200, and a part or the whole of the dummy portion may be attached to the frame 200 (the mask unit sheet portion 220). Thus, the mask 100 and the frame 200 may form an integrated structure.

Fig. 3 is a schematic diagram of a mask 100 according to an embodiment of the invention.

The mask 100 may include a mask unit C formed with a plurality of mask patterns P and a dummy portion DM around the mask unit C. The mask 100 may be manufactured using a metal sheet produced by a rolling process, electroforming, or the like, and one cell C may be formed in the mask 100. The dummy portion DM corresponds to a portion of the mask film 110[ mask metal film 110] other than the cell C, and may include only the mask film 110 or may include the mask film 110 formed with a predetermined dummy portion pattern having a similar form to the mask pattern P. The dummy portion DM corresponds to an edge of the mask 100 and a part or the whole of the dummy portion DM may be attached on the frame 200 (the mask die section 220).

The width of the mask pattern P may be less than 40 μm and the thickness of the mask 100 may be about 5-20 μm. Since the frame 200 has a plurality of mask unit regions CR (CR11 to CR56), a plurality of masks 100 including mask units C (C11 to 56) corresponding to the mask unit regions CR (CR11 to CR56) may be provided. Further, a plurality of templates 50 for supporting a plurality of masks 100, which will be described later, may be provided.

The mask 100 includes a welding portion WP corresponding to an area where welding is performed. The welding parts WP are arranged in plural at predetermined intervals on the edge or dummy part DM portion of the mask 100.

Fig. 4 to 5 are schematic views of a process of forming a mask by bonding a mask metal film on a template to manufacture a mask supporting template according to an embodiment of the present invention. In addition, although the process of forming the mask pattern P after the mask metal film 110 is bonded to the template 50 is described in fig. 4 and 5, the mask 100 (see fig. 3) on which the mask pattern P is formed in advance may be bonded to the template 50, and thus the fabrication of the template 50 for supporting the mask 100 may be completed. The processes of fig. 4 (b) to 5(d) may be omitted for the case of adhering the mask 100 up to the template 50.

Referring to fig. 4 (a), a template (template)50 may be provided. The stencil 50 is a medium having one surface to which the mask 100 is attached and moves the mask 100 in a state of supporting the mask 100. One side of the stencil 50 is preferably a flat surface to support and move the flat mask 100. The center portion 50a may correspond to the mask cell C of the mask metal film 110, and the edge portion 50b may correspond to the dummy portion DM of the mask metal film 110. The stencil 50 has a flat plate shape having an area larger than the mask metal film 110 in order to be able to support the mask metal film 110 as a whole.

In order to allow the laser light L irradiated from the upper portion of the mask 50 to reach the welding portion WP (the region where welding is performed) of the mask 100, the mask 50 may be formed with a laser passing hole 51. The laser passage holes 51 can be formed in the mask 50 in a manner corresponding to the positions and the number of the welds WP. Since the plurality of welding portions WP are arranged at predetermined intervals on the edge or dummy portion DM portion of the mask 100, a plurality of laser passing holes 51 can be formed at predetermined intervals correspondingly. As an example, since a plurality of welding parts WP are arranged at predetermined intervals on both sides (left/right sides) of the dummy part DM portion of the mask 100, a plurality of laser passing holes 51 may also be formed at predetermined intervals on both sides (left/right sides) of the template 50.

The positions and the number of the laser passage holes 51 do not necessarily correspond to the positions and the number of the welded portions WP. For example, the laser L may be irradiated only to a part of the laser passage holes 51 to perform welding. In addition, the laser passage holes 51 in the portions not corresponding to the welding portions WP may be used as alignment marks when aligning the mask 100 and the mask 50. If the material of the template 50 is transparent to the laser light L, the laser passage hole 51 may not be formed.

A temporary bonding portion 55 may be formed on one surface of the template 50. The temporary bonding part 55 may temporarily attach the mask 100[ or the mask metal film 110] to one surface of the stencil 50 and support it on the stencil 50 before the mask 100 is attached to the frame 200.

The temporary bonding portion 55 may use an adhesive that can be separated by heating, an adhesive that can be separated by irradiation with ultraviolet rays.

As an example, the temporary bonding portion 55 may use liquid wax (liquid wax). The liquid wax may be the same wax as that used in the polishing step of the semiconductor wafer or the like, and the type thereof is not particularly limited. As the resin component mainly used for controlling the adhesive force, impact resistance, and the like associated with the holding power, the liquid wax may include substances such as acrylic acid, vinyl acetate, nylon, and various polymers, and solvents. As an example, Acrylonitrile-butadiene rubber (ABR) may be used as the resin component of the temporary bonding portion 55, and SKYLIQUIDABR-4016 containing n-propanol may be used as the solvent component. A liquid wax may be formed on the temporary bonding portion 55 using a spin coating method.

The temporary bonding portion 55, which is liquid wax, has a decreased viscosity at a temperature higher than 85 deg.c to 100 deg.c and an increased viscosity at a temperature lower than 85 deg.c, and a portion is solidified into a solid, so that the mask metal film 110' can be fixedly bonded to the stencil 50.

Then, referring to fig. 4 (b), a mask metal film 110' (or a mask 100 formed with a mask pattern P) may be adhered on the template 50. The liquid wax is heated to 85 c or more and the mask metal film 110 'is brought into contact with the stencil 50, after which the mask metal film 110' and the stencil 50 may be passed between rollers to be bonded.

According to an embodiment, baking (baking) is performed on the template 50 at about 120 ℃ for 60 seconds, thereby vaporizing the solvent of the temporary bonding portion 55, and then a masking metal film lamination (plating) process may be performed immediately thereafter. The lamination is performed by loading a mask metal film 110' on a stencil 50 having a temporary bonding portion 55 formed on one side thereof and passing it between an upper roller (roll) of about 100 c and a lower roller of about 0 c. As a result, the mask metal film 110' can be brought into contact with the template 50 with the temporary bonding portion 55 interposed therebetween.

In addition, when the mask metal film 110 or the mask 100 on which the mask pattern P is formed is bonded to the stencil 50, the mask metal film 110 or the mask 100 may be bonded to the stencil 50 in a state where a tensile force is applied in at least two side directions. Then, with respect to the mask metal film 110, a process of adhering to the stencil 50 in a state of applying a tensile force and forming a mask pattern may be further performed. Thereby, the mask metal film 110 or the mask 100 can be bonded and fixed to the stencil 50 in a state where it has a tensile force by itself. The remaining tensile force is maintained until the mask metal film 110 or the mask is separated from the stencil 50.

Next, referring to fig. 4 (b), one surface of the mask metal film 110' may be planarized PS. The mask metal film 110 'manufactured by the rolling process may be reduced in thickness (110' - >110) by the planarization PS process. In addition, the mask metal film 110 produced by the electroforming process may be subjected to the planarization PS process to control the surface characteristics and thickness thereof.

Therefore, as shown in (c) of fig. 4, as the thickness of the mask metal film 110 'is reduced (110' - >110), the thickness of the mask metal film 110 may be about 5 μm to 20 μm. In addition, the mask metal film 110 in which the patterning PS process is completed may be used without (c) of fig. 4.

Then, referring to fig. 5(d), a patterned insulating portion 25 may be formed on the mask metal film 110. The insulating portion 25 may be formed of a photoresist material using a printing method or the like.

Next, etching of the mask metal film 110 may be performed. Dry etching, wet etching, or the like may be used, and there is no particular limitation thereto. As a result of the etching, the mask metal film 110 exposed at the empty positions 26 between the insulating portions 25 is partially etched. The etched portion of the mask metal film 110 constitutes a mask pattern P, so that the mask 100 formed with a plurality of mask patterns P can be manufactured.

Then, referring to fig. 5 (e), the fabrication of the template 50 supporting the mask 100 may be completed by removing the insulating part 25.

Next, a process of manufacturing the mask 100 by forming the mask pattern P on the mask metal film 110 will be described.

Fig. 6 is a schematic view showing the etching degree (d) of a mask according to the conventional mask manufacturing processes [ (a) to (c) ] and a comparative example.

Referring to fig. 6, the conventional mask manufacturing process only performs wet etching (wet etching).

First, as shown in fig. 6 (a), a patterned photoresist M may be formed on a planarizing film 110' (sheet). Then, as shown in fig. 6 (b), wet etching WE may be performed through the space between the patterned photoresist M. After wet etching WE is performed, a part of the space of the film 110 'is penetrated, so that a mask pattern P' may be formed. Then, if the photoresist M is cleaned, the fabrication of the film 110' formed with the mask pattern P ', i.e., the mask 100', may be completed.

As shown in fig. 6 (c), the conventional mask 100 'has a problem that the size of the mask pattern P' is not necessarily large. Since wet etching WE proceeds isotropically, the etched form is approximately in the shape of a circular arc. Further, since it is difficult to make the etching rate uniform in each portion during wet etching WE, the widths R1', R1", R1 '" of the through pattern after penetrating the film 110' are different from each other. In particular, in the pattern in which the undercuts UC (undercut) frequently occur, not only the lower width R1 "but also the upper width R2" of the mask pattern P ' are formed to be wide, and the lower widths R1', R1' "and the upper widths R2', R2 '" in the pattern in which the undercuts UC are less frequently occur are relatively formed to be narrow.

As a result, the conventional mask 100 'has a problem that the sizes of the respective mask patterns P' are not uniform. For the ultra-high quality OLED, the QHD quality is 500-600PPI (pixel per inch), the pixel size reaches about 30-50 μm, and the 4K UHD and 8K UHD high quality has higher resolution of-860 PPI and-1600 PPI, so the slight size difference may cause the product defect.

Referring to fig. 6 (d), since the wet etching WE proceeds isotropically, the etched form is approximately in the shape of a circular arc. In addition, in the wet etching, the etching speed of each portion is hardly exactly the same, and if the mask metal film 110 is penetrated by only 1 wet etching to form a mask pattern, the deviation thereof is larger. For example, although the mask patterns 111 and 112 have different wet etching rates, the difference in the top width (undercut) is not very large. However, the difference between the lower width PD1 of the mask metal film 110 penetrated by the formation of the mask pattern 111 and the lower width PD2 of the mask metal film 110 penetrated by the formation of the mask pattern 112 is much larger than the difference in the upper width. This is a result of wet etching proceeding isotropically. In other words, the width determining the pixel size is the lower width PD1, PD2 of the mask patterns 111, 112, not the upper width, and thus, a scheme of controlling the lower width PD1, PD2 using a wet etching method other than 1 wet etching may be considered.

Therefore, according to an aspect of the present invention, the accuracy of the mask pattern during the wet etching process may be improved by the wet etching a plurality of times.

Fig. 7 to 8 are schematic views of a manufacturing process of a mask according to an embodiment of the present invention.

Referring to fig. 7 (a), first, a mask metal film 110 as a metal sheet may be provided. The mask metal film 110 may be formed by a rolling process, electroforming, or the like, and the material of the mask metal film 110 may be invar (invar), super invar (super invar), nickel (Ni), nickel-cobalt (Ni-Co), or the like.

Then, a patterned 2 nd-1 st insulating portion M1 may be formed on one side (upper surface) of the mask metal film 110. The 2 nd-1 st insulating part M1 may be formed of a photoresist material by a printing method or the like. The insulation portions M1, M2, and M3 in fig. 7 to 8 correspond to the second insulation portion 25 described later in fig. 10, and are different from the first insulation portion 23, and therefore it should be noted that: hereinafter, the insulation portions M1, M2, and M3 are referred to as a 2-1 st insulation portion M1, a 2-2 nd insulation portion M2, and a 2-3 rd insulation portion M3.

The 2 nd-1 st insulating part M1 may be a black matrix photoresist (black matrix photoresist) or a photoresist material on which a metal plating film is formed. The material of the 2 nd-1 st insulating section M1 may be a photoresist material different from that of the 2 nd-2 nd insulating section M2 or the 2 nd-3 rd insulating section M3 described later, and may preferably be an epoxy resin-based photoresist material. The black matrix photoresist may be a material including a black matrix resin (black matrix) for forming a black matrix of the display panel. The black matrix photoresist may have a superior light blocking effect than general photoresists. In addition, the photoresist having the metal plating film formed thereon has a good light shielding effect of shielding light irradiated from the upper portion by the metal plating film. The 2 nd-1 st insulating part M1 may be a positive type photoresist material.

Then, referring to fig. 7 (b), a first mask pattern P1' of a predetermined depth may be formed on one side (upper surface) of the mask metal film 110 by wet etching WE 1. When wet etching WE1 is performed, it should not penetrate the mask metal film 110. Accordingly, the first mask pattern P1' does not penetrate the mask metal film 110 and may be formed in a substantially circular arc shape. That is, the depth value of the first mask pattern P1' may be smaller than the thickness of the mask metal film 110.

The wet etching WE1 has isotropic etching characteristics, and thus the width R2 of the first mask pattern P1 is different from the pitch R3 between the patterns of the 2-1 st insulating part M1, and may have a width wider than the pitch R3 between the patterns of the 2-1 st insulating part M1. In other words, since the undercuts UC (undercut) are formed at both lower portions of the 2-1 st insulating part M1, the width R2 of the first mask pattern P1 may have an extra width to form the undercuts UC than the interval R3 between the patterns of the 2-1 st insulating part M1.

Then, referring to fig. 7 (c), a2 nd-2 nd insulating portion M2 may be formed on one surface (upper surface) of the mask metal film 110. The 2 nd-2 nd insulating part M2 may be formed of a photoresist material by a printing method or the like. The 2 nd-2 nd insulating portion M2 is preferably made of a positive photoresist material because it needs to remain in a space where an undercut UC is formed, which will be described later.

Since the 2 nd-2 nd insulating part M2 is formed on one side (upper surface) of the mask metal film 110, a portion is formed on the 2 nd-1 st insulating part M1 and the other portion is filled inside the first mask pattern P1.

The 2 nd-2 nd insulating portion M2 may use a photoresist diluted (dilution) in a solvent. If a high concentration photoresist solution is formed on the mask metal film 110 and the 2-1 st insulating part M1, the high concentration photoresist solution reacts with the photoresist of the 2-1 st insulating part M1, thereby possibly melting a portion of the 2-1 st insulating part M1. Therefore, in order not to affect the 2 nd-1 st insulating part M1, the 2 nd-2 nd insulating part M2 may use a photoresist whose concentration is decreased by dilution in a solvent.

Then, referring to (d) of fig. 8, a portion of the 2 nd-2 nd insulating portion M2 may be removed. As an example, a portion of the second insulating portion M2 may be volatilized and removed by baking. The solvent of the 2 nd-2 nd insulating portion M2 is volatilized by the baking process to leave only the photoresist component. Accordingly, the 2 nd-2 nd insulating part M2' leaves a thin portion, such as a coated film, at the exposed portion of the first mask pattern P1 and the surface of the 2 nd-1 st insulating part M1. The thickness of the remaining 2 nd-2 nd insulating part M2' is preferably less than about several μ M so as not to affect the pattern width R3 of the 2 nd-1 st insulating part M1 or the pattern width R2 of the first mask pattern P1.

Then, referring to fig. 8 (e), exposure L may be performed on one side (upper surface) of the mask metal film 110. The 2-1 st insulating part M1 may function as an exposure mask when the exposure L is performed on the upper portion of the 2-1 st insulating part M1. Since the 2 nd-1 st insulating part M1 is a black matrix photoresist (black matrix photoresist) or a photoresist material on which a metal plating film is formed, the light shielding effect is excellent. Therefore, the 2 nd-2 nd insulation part M2 ″ [ refer to (f) of fig. 8 ] located vertically below the 2 nd-1 st insulation part M1 is not exposed to light L, and the other 2 nd-2 nd insulation parts M2' are exposed to light L.

Then, referring to (f) of fig. 8, if development is performed after the exposure L, a portion of the 2 nd-2 nd insulating part M2 ″ that is not exposed by the exposure L is left, and the other 2 nd-2 nd insulating part M2' is removed. Since the 2 nd-2 nd insulating portion M2' is a positive type photoresist, the portion exposed to light L is removed. The space where the 2 nd-2 nd insulating portion M2 ″ remains can correspond to a space where undercuts UC [ refer to step (b) of fig. 7 ] are formed in the lower portions of both sides of the 2 nd-1 st insulating portion M1.

Then, referring to fig. 8 (g), wet etching WE2 may be performed on the first mask pattern P1 of the mask metal film 110. The wet etching liquid can penetrate into the spaces between the patterns of the 2 nd-1 st insulating portion M1 and the spaces of the first mask pattern P1, thereby performing wet etching WE 2. The second mask pattern P2 may be formed through the mask metal film 110. That is, the first mask pattern P1 is formed by penetrating the other surface of the mask metal film 110 from the lower end thereof.

At this time, the 2 nd-2 nd insulating portion M2 ″ remains on the first mask pattern P1. The remaining 2 nd-2 nd insulating portion M2 ″ may function as a mask for wet etching. That is, the 2 nd-2 nd insulating part M2 ″ masks (masking) the etching liquid to prevent the etching liquid from etching in a side surface direction of the first mask pattern P1, but in a lower surface direction of the first mask pattern P1.

Since the 2 nd-2 nd insulation part M2 "is disposed in the undercut UC space of the vertically lower portion of the 2 nd-1 st insulation part M1, the pattern width of the 2 nd-2 nd insulation part M2" substantially corresponds to the pattern width R3 of the 2 nd-1 st insulation part M1. Thus, the second mask pattern P2 corresponds to wet etching WE2 performed on the space R3 between the patterns of the 2 nd-1 st insulating part M1. Accordingly, the width R1 of the second mask pattern P2 may be less than the width R2 of the first mask pattern P1.

Since the width of the second mask pattern P2 defines the width of the pixel, the width of the second mask pattern P2 is preferably less than 35 μm. If the thickness of the second mask pattern P2 is excessively thick, it is difficult to control the width R1 of the second mask pattern P2, and the uniformity of the width R1 is degraded, and the shape of the mask pattern P as a whole may not be tapered/reverse tapered, so the thickness of the second mask pattern P2 is preferably smaller than that of the first mask pattern P1. The thickness of the second mask pattern P2 is preferably close to 0, and when considering the size of the pixel, for example, the thickness of the second mask pattern P2 is preferably about 0.5 to 3.0 μm, and more preferably 0.5 to 2.0 μm.

The sum of the shapes of the connected first and second mask patterns P1 and P2 may constitute a mask pattern P.

Then, referring to (h) of fig. 8, the manufacture of the mask 100 may be completed by removing the 2 nd-1 st insulating part M and the 2 nd-3 rd insulating part M3. The first mask pattern P1 includes an inclined plane and the height of the second mask pattern P2 is very low, so if the shapes of the first mask pattern P1 and the second mask pattern P2 are combined, the whole assumes a tapered shape or an inverted tapered shape.

In addition, between the steps (b) and (c) of fig. 7, the steps (b2) and (b3) may be further performed.

Referring to (b2) of fig. 7, a 2-3 rd insulating part M3 may be formed within the first mask pattern P1'. The 2-3 th insulation part M3 may be formed on at least a portion of the first mask pattern P1' exposed between the 2-1 st insulation parts M1. For example, the 2-3 nd insulation part M3 having a width R3 may be formed in an interval of patterns of an adjacent pair of the 2-1 st insulation parts M1, i.e., on the first mask pattern P1'.

For the convenience of exposure, a negative type photoresist material is preferably used for the 2 nd to 3 rd insulating part M3. When the upper portion is exposed after filling the negative photoresist in the first mask pattern P1', the 2 nd-1 st insulating portion M1 functions as an exposure mask with respect to the 2 nd-3 rd insulating portion M3, and thus only the 2 nd-3 rd insulating portion M3 exposed between the patterns of the 2 nd-1 st insulating portion M1 remains. At this time, as illustrated in (c) of fig. 7, a2 nd-3 rd insulating part M3 having a width R3 may be formed on the first mask pattern P1'.

Then, referring to fig. 7 (b3), wet etching WE2 may be further performed on the first mask pattern P1'. Since the 2 nd to 3 rd insulating part M3 is partially formed in the first mask pattern P1', the first mask pattern P1' is not further etched downward but is etched in a lateral direction. Accordingly, the width of the first mask pattern P1 'may be greater than R2(P1' - > P1).

Specific reasons for performing the steps (b2) and (b3) of fig. 7 are as follows.

If the first mask pattern P2, which will be described later in fig. 8, is formed immediately after the steps (b2) and (b3) of fig. 7 are omitted and the first mask pattern P1' is formed, it may result in that it may be difficult to reduce the taper angles of the mask patterns P ' (P1', P2). Based on the feature of the isotropic etching process of the first mask pattern P1', it is difficult for the side to have a small angle (an angle formed by a horizontal plane and the side of the mask pattern), and since the angle exceeds 60 ° or is nearly vertical, there is a case where the angle exceeds 70 ° even though the wet etching is performed twice. As a whole, the Shadow Effect (Shadow Effect) can be effectively prevented only when the side of the mask pattern P forms an angle of about 30 ° to 70 ° with the horizontal plane, and if the angle is exceeded, the Shadow Effect is still generated, so that it is difficult to uniformly form the OLED pixel.

In addition, in order to form the surface of the mask pattern P uniformly without roughness, the wet etching process needs to be performed in a short time. However, if the wet etching process is performed in a short time, the first mask pattern P1' is hardly formed at a small side angle. Finally, if the wet etching process is performed for a long time in order to form the side angle of the first mask pattern P1' into a small angle, there occurs a problem in that the surface of the mask pattern is rough and the morphology is not uniform.

Therefore, the 2 nd to 3 rd insulating part M3 is further formed in the first mask pattern P1 'to prevent the lower portion of the first mask pattern P1' from being etched, and as wet etching WE3(P1'- > P1) is further performed in the side direction of the first mask pattern P1', there is an effect that the angle (a1- > a2) formed by the side of the first mask pattern P1 and the horizontal plane can be reduced. Since the wet etching is performed in two times to form the first mask pattern P1, each etching process does not need to be continued for a long time, and the surface morphology of the mask pattern P can be uniformly formed.

After the first mask pattern P1 in which the angle a2 between the side and the horizontal plane becomes smaller is formed by further performing wet etching WE3, the 2 nd-3 rd insulating part M3 may be removed.

Fig. 9 is a schematic diagram of the degree of etching of a mask according to an embodiment of the present invention.

The processes up to (a) of fig. 9 are the same as those described in (a) to (b) of fig. 7. In fig. 9 (a), the first mask pattern P1-1 exhibiting different etching degrees in the wet-etch WE1 of the 2-1 st insulating part M1 is compared with the first mask pattern P1-2 and explained.

Referring to fig. 9 (a), even though the same wet etching WEs 1-1 and WE1-2 occurs, different etching processes occur according to etching portions, as shown in the first mask pattern P1-1 and the first mask pattern P1-2. The pattern width R2-1 of the first mask pattern P1-1 is smaller than the pattern width R2-2 of the first mask pattern P1-2, and such a difference in the pattern widths R2-1 and R2-2 adversely affects the resolution of the pixel.

Then, referring to fig. 9 (b), it can be confirmed that the vertical lower space of the 2-1 st insulation part M1 is formed with the 2-2 nd insulation parts M2"-1, M2" -2, respectively, after the processes illustrated in fig. 7 (c) to 8 (f) are performed. The 2 nd-2 nd insulation parts M2"-1, M2" -2 are formed in different sizes from each other according to the size of the undercut space at the lower portion of the 2 nd-1 st insulation part. Although the size of the 2 nd-2 nd insulating part M2 ″ -1 is smaller than the size of the 2 nd-2 nd insulating part M2 ″ -2, the pattern widths of the 2 nd-2 nd insulating parts M2 ″ -1 and M2 ″ -2 are the same. The pattern width R3 of each of the 2 nd-2 nd insulating parts M2 ″ -1, M2 ″ -2 may be the same to correspond to the pattern width R3 of the 2 nd-1 st insulating part M1.

Then, referring to fig. 9 (c), wet etching WE2 is performed using the 2 nd to 2 nd insulating portions M2 ″ -1 and M2 ″ -2 as masks for the wet etching, respectively, so that the masking metal film 110 can be penetrated. As a result, the deviation of the widths R1-1 and R1-2 of the formed second mask patterns P2-1 and P2-2 is significantly smaller than the deviation of the widths R2-1 and R2-2 of the first mask patterns P1-1 and P1-2. This is because the pattern width of the 2-2 nd insulating portions M2"-1 and M2" -2 formed by the second wet etching is substantially the same as the pattern width of the 2-1 st insulating portion M1 formed by the first wet etching, while the second wet etching is performed on the thickness of the remaining mask metal film 110 after the first wet etching is performed on the mask metal film 110 at the depth of the first mask patterns P1-1 and P1-2.

As described above, the mask manufacturing method of the present invention has an effect of forming the mask pattern P of a desired size by performing wet etching a plurality of times. Specifically, as part of the 2 nd-2 nd insulating part (M2") is remained, the wet etching WE2 forming the second mask pattern P2 will be performed in a thinner width and a thinner thickness than the wet etching WE1, WE2 forming the first mask pattern P1, and thus has an advantage of easily controlling the width R1 of the second mask pattern P2. On the other hand, since the inclined surface can be formed by wet etching, the mask pattern P that can prevent the shadow effect can be formed.

Fig. 10 is a schematic view of a process of manufacturing a mask support template according to an embodiment of the present invention.

The present invention may perform the formation process of the mask pattern P of fig. 7 to 8 after the mask metal film 110 is adhered to the stencil 50. The processes of (a), (b), (c) of fig. 10 correspond to the processes of (c) of fig. 4, (d), (e) of fig. 5, and thus the description of the same parts will be omitted.

Referring to fig. 10 (a), the mask metal film 110 may be bonded to the stencil by interposing a temporary bonding portion 55. However, it should be prevented that the etching solution enters the interface between the mask metal film 110 and the temporary bonding portion 55 to damage the temporary bonding portion 55/the template 50, thereby causing an etching error of the mask pattern P. Thereby, the mask metal film 110 can be bonded to the upper surface of the stencil 50 in a state where the first insulating portion 23 is formed on one surface of the mask metal film 110. That is, the surface of the mask metal film 110 on which the first insulating portion 23 is formed may be directed to the upper surface of the mask 50. The mask metal film 110 and the template 50 may be bonded to each other by interposing the first insulating portion 23 and the temporary bonding portion 55.

The first insulating portion 23 may be formed on the mask metal film 110 by a printing method or the like from a photoresist material that is not etched by an etching solution. In addition, in order to maintain a circular shape after a plurality of wet etching processes, the first insulating portion 23 may include at least one of a cured negative photoresist, a negative photoresist containing an epoxy resin. As an example, it is preferable to use an epoxy SU-8 photoresist or a black matrix photoresist and cure them together in the processes of baking the temporary bonding portion 55, baking the second insulating portion M2 (see fig. 8 (d)), and the like.

Then, referring to fig. 10 (b), a patterned second insulating portion 25 may be formed on the mask metal film 110. The second insulation part 25 corresponds to the insulation part 25 of fig. 5(d), or may correspond to the second insulation parts M1, M2, and M3 of fig. 7 to 8.

Next, etching of the mask metal film 110 may be performed. The mask pattern P may be formed using the etching method of fig. 5(d) or the etching methods of fig. 7 to 8.

Then, referring to fig. 10 (c), the fabrication of the template 50 supporting the mask 100 may be completed by removing the second insulating part 25. A mask supporting template including the mask 100/the first insulating portion 23/the temporary bonding portion 55/the template 50 may be manufactured.

The reason for manufacturing the mask supporting template further including the first insulating portion 23 will be described in more detail below.

FIG. 11 is a schematic diagram of a mask etch profile according to a comparative example and an embodiment of the present invention.

As shown in fig. 7 to 8, it is more advantageous to perform etching on only one side (e.g., the upper surface) of the mask metal film 110. If etching is performed simultaneously on both sides, the thickness of the mask metal film 110 may be uneven, and it may be difficult to obtain a desired form of the mask pattern P. It is important that wet etching WE is performed on one surface, and that etching liquid does not leak to the other surface (for example, the lower surface) of the mask metal film 110 because wet etching is performed a plurality of times.

Fig. 11(a) is a comparative example in which the mask metal film 110 is bonded to the template 50 with the temporary bonding portion 55 interposed therebetween without the first insulating portion 23. As detailed in (g) of fig. 8, since the thickness of the first mask pattern P1(P1-1, P1-2) is relatively thick and the width of the second mask pattern P2 defines the width of the pixel, the width of the second mask pattern P2 is preferably close to 0 μm.

Therefore, although the first mask pattern P1 is preferably formed to the maximum depth, even though the wet etches WE1-1 and WE1-2 are the same, the etching degree is different depending on the etching portion, as shown in the first mask pattern P1-1 and the first mask pattern P1-2. As with the first mask pattern P1-2' on the right side of fig. 11(a), an etching WE1-2 that penetrates the mask metal film 110 may occur.

In this case, the temporary bonding portion 55 exposed at the lower portion may be damaged (55- >55') by wet etching WE 1-2. The template 50 may be damaged in addition to the temporary bonding portion 55'.

In addition, when the etching liquid enters between the interface of the damaged temporary bonding portion 55 'and the mask metal film 110 (WE1-2'), the lower portion of the first mask pattern P1 is further etched, thereby causing a problem that the size of the pattern is excessively formed or a local amorphous defect is generated.

Therefore, in the present invention, by further interposing the first insulating portion 23 between the mask metal film 110 and the temporary bonding portion 55, even if the first mask pattern P1-2 is formed to penetrate the mask metal film 110 in the first wet etching WE1(WE1-1, WE1-2), the etching liquid can be prevented from entering the lower surface of the mask metal film 110.

Since the first insulating portion 23 includes at least one of a cured negative photoresist, a negative photoresist containing an epoxy resin, and a black matrix photoresist (black matrix), it can withstand without being melted by an etching solution even if a subsequent etching process such as the first wet etching WE1 process, the second wet etching WE2, the third wet etching WE3, and the like is performed. Thus, even if the first mask pattern P1-2 penetrates the mask metal film 110, the width of the pattern is not enlarged and has an effect that the width corresponding to the 2-1 st insulating part M1 can be maintained.

Fig. 12 is a schematic view of a state where the template 50 is loaded on the frame 200 and the mask 100 corresponds to the cell region CR of the frame 200 according to an embodiment of the present invention. Fig. 12 illustrates a case where one mask 100 is attached to the cell region CR, but a plurality of masks 100 may be attached to the frame 200 by simultaneously attaching the masks 100 to all the cell regions CR. In this case, there may be a plurality of templates 50 for respectively supporting a plurality of masks 100.

The template 50 may be removed by a vacuum chuck 90. The mask 100 may be transferred by sucking the surface of the template 50 opposite to the surface thereof to which the mask is adhered by a vacuum chuck 90. The vacuum chuck 90 does not affect the adhesion state and alignment state of the mask 100 in the process of transferring the stencil 50 to the frame 200 after adsorbing the stencil 50 and turning it over.

Then, referring to fig. 12, the mask 100 may correspond to one mask unit region CR of the frame 200. The correspondence of the mask 100 with the mask unit region CR may be achieved by loading the stencil 50 on the frame 200 (or the mask unit sheet part 220). Whether the mask 100 corresponds to the mask unit region CR or not can be observed through a microscope while controlling the position of the template 50/vacuum chuck 90. Since the template 50 presses the mask 100, the mask 100 and the frame 200 may be closely abutted.

In addition, the lower support 70 may be further disposed at the lower portion of the frame 200. The lower supporter 70 may press an opposite surface of the mask unit region CR in contact with the mask 100. At the same time, since the lower supporter 70 and the mask 50 press the edge of the mask 100 and the frame 200 (or the mask die parts 220) in opposite directions to each other, the alignment state of the mask 100 can be maintained without being disturbed.

Next, the mask 100 may be irradiated with laser light L and the mask 100 may be attached to the frame 200 based on the laser welding. The welding portion of the mask laser-welded generates a welding bead WB, which may have the same material as the mask 100/frame 200 and be integrally connected with the mask 100/frame 200.

Fig. 13 is a schematic view of a process of separating the mask 100 from the template 50 after attaching the mask 100 to the frame 200 according to an embodiment of the present invention.

Referring to fig. 13, after the mask 100 is attached to the frame 200, the mask 100 and the stencil 50 may be separated (bonding). The mask 100 and the template 50 can be separated by at least one of heating ET, chemical treatment CM, application of ultrasonic waves US, and application of ultraviolet rays UV to the temporary bonding portion 55. Since the mask 100 remains attached to the frame 200, only the stencil 50 may be lifted. As an example, if heat ET of a temperature higher than 85 ℃ -100 ℃ is applied, the viscosity of the temporary bonding portion 55 is lowered, the bonding force of the mask 100 and the stencil 50 is weakened, and thus the mask 100 and the stencil 50 can be separated. As another example, the mask 100 and the template 50 may be separated by immersing the temporary adhesion portion 55 with CM in a chemical such as IPA, acetone, ethanol, or the like, in such a manner that the temporary adhesion portion 55 is dissolved, removed, or the like. As another example, the mask 100 and the stencil 50 may be separated by weakening the adhesive force of the mask 100 and the stencil 50 by applying the ultrasonic wave US or applying the ultraviolet ray UV.

In addition, if the mask metal film 110 or the mask 100 is bonded to the mask 50 in a state where a tensile force is applied in a side direction of the mask metal film 110 or the mask 100 when the mask metal film 110 or the mask 100 is bonded to the mask 50, the tensile force applied to the mask 100 when the mask is separated from the mask 100 is released and the mask can be converted into a tensile force that tightens both sides of the mask 100. Thus, the mask 100 can be attached in a tight state by applying tension to the frame 200 (the mask unit sheet portion 220).

Fig. 14 is a schematic view of a state in which the mask 100 is attached to the frame 200 and the insulating part 23 is removed, according to an embodiment of the present invention. Fig. 14 illustrates a state in which all the masks 100 are attached to the cell regions CR of the frame 200. Although the templates 50 may be separated after the masks 100 are attached one by one, all the templates 50 may be separated after all the masks 100 are attached.

The template 50 is separated from the mask 100 by the vacuum chuck 90, and the first insulating portion 23 remains on the upper surface of the mask 100. If the first insulating portion 23 is a cured photoresist, it is difficult to remove by a wet etching process. Therefore, in order to remove the first insulating portion 23 on the mask 100, at least one of the plasma PS and the ultraviolet light UV may be applied. A process of removing only the first insulating layer 23 by applying a high pressure plasma or a vacuum plasma PS or an ultraviolet UV after loading the frame-integrated masks 100 and 200 into another chamber (not shown) may be performed.

As described above, the present invention has an effect of being able to accurately control the size and position of the mask pattern P at the time of the process of forming the mask pattern by using the mask supporting template including the mask metal film 110/the first insulating portion 23/the temporary bonding portion 55/the template 50.

FIG. 15 is a schematic view of a mask according to other embodiments of the present invention.

Referring to fig. 1, in the related art, in order to attach a strip-shaped mask 10 to a frame 20 after stretching it, welding W is performed only on both sides (left/right sides) of the strip-shaped mask 10. Since only two sides of the strip-shaped mask 10 correspond to the frame 20 and the other two sides (upper/lower sides) hardly correspond to the frame 20, the welding W can be performed only at two sides. Therefore, the two sides (left/right sides) fixed by the welding W and the other two sides (upper/lower sides) may generate a difference in applied tension. Both sides (left/right sides) are attached tightly, and the other both side (upper/lower side) portions have a problem of deformation such as sagging or wrinkles.

Therefore, it is a feature of the present invention that all sides (e.g., four sides, upper, lower, left, and right) are welded instead of two sides when the mask 100 is attached to the frame 200. As shown in fig. 15, the welding parts WP (WP1), i.e., areas to be welded, may be arranged at predetermined intervals along four sides of the mask 100. If welding is performed along the four sides of the mask 100 (refer to fig. 12 or 16), the four sides of the mask are all attached to the frame 200, and thus the four sides apply or receive uniform tension to the frame 200. Thus, the present invention has an effect of preventing deformation from occurring on all sides of the mask 100.

Further, the present invention is characterized in that the mask 100 is further welded at the vertex portions of the four sides. Referring to fig. 15, as the area to be welded, the welded part WP will be arranged in a quadrangular shape as a whole. Therefore, after the mask 100 is welded to the frame 200, there is a risk of stress concentration at the welded quadrangular apex portion. If the apex portion is stress-concentrated and wrinkles are generated, an alignment error may occur in the mask pattern P as a whole. Accordingly, the apex portion of the mask 100 may be welded by further arranging the welded portion WP 2.

The spacing of welds WP2 may be less than the spacing between welds WP 1. For example, if the pitch between the welding portions WP1 is 2mm, the pitch between the welding portions WP2 may be set to 1 mm. Further, even if the pitch of the welds WP2 is the same as the pitch of the welds WP1, a greater number of welds WP2 may be arranged per unit area. Fig. 15 illustrates an arrangement of 3 welding portions WP2 in the lateral direction and 3 in the vertical direction, but there is no limitation on the arrangement form of the welding portions WP 2. Since the welding portions WP2 are arranged more closely than the welding portions WP1, more welding beads WB generated by welding may be produced at the apex portion of the mask 100, and the mask 100 is stably fixedly attached to the frame 200, and thus there is a further effect that deformation such as wrinkles, drooping, and the like of the mask 100 may be prevented even if the remaining welding portions WP1 are welded.

When welding portion WP (WP1, WP2) is welded by laser irradiation, the thickness of welding portion WP may be larger than the thickness of the remaining region in order to form bead WB sufficiently and weld stably.

Fig. 16 is a schematic view of a process of loading a template onto a frame so that a mask corresponds to and is attached to a unit region of the frame according to another embodiment of the present invention.

A process of loading the template 50 according to another embodiment onto the frame 200 to correspond/attach the mask 100 to the frame 200 is as detailed in fig. 12 to 14. Only, referring to fig. 16, the welding parts WP are arranged in plural at a predetermined pitch on the dummy portion DM portions of the four sides (upper, lower, left, and right) of the mask 100, and thus a plurality of laser passing holes 51 may be formed at predetermined intervals on the four sides (upper, lower, left, and right) of the template 50. The welding portion WP2 may be further formed at the apex portion of the mask 100, and the laser passage hole 51 may be further formed at the apex portion of the mask 50 in accordance therewith.

When the mask 100 is irradiated with the laser light L, the laser light L may first irradiate the welding portion WP2 to fixedly attach the apex of the mask 100 to the frame 200 in a tight manner, and then irradiate the welding portion WP1 to complete the attachment process. Alternatively, the laser light L may be irradiated to all the side surfaces of the mask 100 at the same pitch, that is, at the pitch of the welded portion WP1 and first attached, and then the welded portion WP2 may be further irradiated with the laser light L and the attached state may be reinforced again. Alternatively, the irradiation of the welded portion WP1 or the welded portion WP2 may be controlled while observing the deformation state between the mask 100 and the frame 200 in real time during the irradiation of the laser light L.

As described above, the present invention can prevent the mask from deformation such as wrinkles or distortion by arranging the welding parts on the four sides or the additional vertex parts on the four sides of the mask to stably perform welding attachment on the frame.

As described above, although the preferred embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is not limited to the embodiments, and various modifications and changes can be made by those skilled in the art without departing from the spirit of the present invention. Such modifications and variations are considered to be within the purview and scope of the invention and the appended claims.