TW202013447A - Producing method of mask integrated frame and frame - Google Patents

Abstract

The present invention relates to a method for manufacturing a frame-integrated mask. The method for manufacturing a frame-integrated mask according to the present invention, which is a method for manufacturing a frame-integrated mask including at least one mask integrally formed with a frame for supporting the mask, comprises the steps of: (a) providing a frame having at least one mask cell region; (b) providing a mask; (c) matching the mask with the mask cell region of the frame; and (d) irradiating a welding part of the mask with a laser to bond the mask to the frame, wherein: a plurality of adsorption holes are formed through parts which are spaced apart a predetermined distance from the corners of the frame having the mask cell region existing thereon; and in step (c), through the plurality of adsorption holes, an adsorptive force is applied to the mask being in contact with the frame, so that the mask is made to closely adhere to the frame.

Description

Frame integrated mask manufacturing method and frame

The invention relates to a manufacturing method and a frame of a frame-integrated mask. In more detail, the mask can be stably supported and moved without deformation, and when the mask is adhered to the frame, the adhesion between the mask and the frame can be improved, and the alignment between the various masks ( align) precise frame integrated mask manufacturing method and frame.

As a technology for forming pixels in the OLED manufacturing process, a FMM (Fine Metal Mask) method is mainly used, which closely adheres a shadow mask in the form of a thin film to a substrate and deposits organic matter at a desired position.

In the existing OLED manufacturing process, after the mask is manufactured into a strip shape, a plate shape, etc., the mask is welded and fixed to the OLED pixel deposition frame and used. Multiple units corresponding to one display may be provided on one mask. In addition, in order to manufacture a large-area OLED, a plurality of masks can be fixed to the OLED pixel deposition frame. During the process of fixing to the frame, each mask is stretched to make it flat. It is very difficult to adjust the stretching force to flatten the entire part of the mask. In particular, in order to flatten all the cells and align the mask pattern with a size of only a few μm to several tens of μm, it is necessary to fine-tune the stretching force applied to each side of the mask and confirm the height of the alignment state in real time Claim.

Nevertheless, in the process of fixing multiple masks to one frame, there is still a problem of poor alignment between the masks and between the mask units. In addition, in the process of welding and fixing the mask to the frame, the thickness of the mask film is too thin and the area is large, so there is a problem that the mask sags or twists due to load, and wrinkles and burrs that occur in the welded part during the welding process (burr), etc. problems such as misalignment of the mask unit.

In ultra-high-definition OLED, the existing QHD (Quarter High Definition) image quality is 500-600PPI (pixel per inch), the pixel size reaches about 30-50μm, and 4K UHD (Ultra High Definition), 8K UHD HD has a comparison The higher resolution is ~860PPI, ~1600PPI, etc. In this way, considering the pixel size of the ultra-high-definition OLED, the alignment error between the units needs to be reduced to a degree of several μm. Exceeding this error will result in defective products, 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 accurately aligning it, and a technique of fixing the mask to the frame and the like.

Problems to be solved by invention Therefore, the present invention is proposed to solve the above-mentioned problems in the prior art. When the mask is adhered to the frame, it can prevent the deformation of the mask and improve the adhesion between the mask and the frame. Method and framework.

In addition, an object of the present invention is to provide a method for manufacturing a frame-integrated mask in which the mask and the frame can form an integrated structure.

In addition, an object of the present invention is to provide a method and frame for manufacturing a frame-integrated mask that can prevent deformation such as sagging or twisting of the mask and can be accurately aligned.

In addition, an object of the present invention is to provide a method for manufacturing a frame-integrated mask that significantly reduces manufacturing time and significantly improves productivity.

Ways to solve the problem The above object of the present invention is achieved by a method for manufacturing a frame-integrated mask that integrates at least one mask with a frame for supporting the mask, wherein the method includes the following steps: (a) providing at least one The frame of the mask unit area; (b) provide the mask; (c) make the mask correspond to the mask unit area of the frame; and (d) irradiate laser to the welding part of the mask to make the mask adhere to the frame , A plurality of suction holes are formed at a predetermined distance from the corner of the frame where the mask unit area is provided, and in step (c), a suction force is applied to the mask in contact with the frame through the multiple suction holes, so that The mask is tightly attached to the frame.

Step (b) may include the following steps: (b1) forming a mask metal film by electroforming on at least one side of the conductive substrate; (b2) separating the mask metal film from the conductive substrate; (b3) The mask metal film is adhered to the template on which one temporary bonding part is formed; and (b4) A mask pattern is formed on the mask metal film to manufacture the mask.

Step (b) may include the following steps: (b1) providing a mask metal film, the mask metal film being a sheet manufactured by rolling; (b2) bonding the mask metal film to one side to form On the template of the temporary bonding part; (b3) forming a mask pattern on the mask metal film to manufacture a mask.

Step (c) may be a step of loading the template on the frame and making the mask correspond to the mask unit area of the frame.

In step (c), a lower support body may be arranged at a lower portion of the frame, the lower support body including an adsorption portion for generating suction pressure.

The lower support may squeeze the opposite side of the mask unit area for loading the mask.

The suction hole may be formed on a portion that does not overlap the welding portion of the mask.

The conductive substrate is a wafer, and a process of heat-treating the mask metal film is further performed between step (b1) and step (b2).

Between step (b1) and step (b2), a step of reducing the thickness of the mask metal film bonded on the template is also included. The thickness reduction of the mask metal film can be performed by CMP (Chemical Mechanical Polishing) or chemical wet etching (chemical Any one of wet etching and dry etching.

The temporary adhesive part may be an adhesive or adhesive sheet that is separable based on heating, and an adhesive or adhesive sheet that is separable based on UV irradiation.

The steps of forming a mask pattern on the mask metal film to manufacture a mask include: (1) forming a patterned insulating portion on the mask metal film; (2) performing a portion of the mask metal film exposed between the insulating portions Etching to form a mask pattern; and (3) removing the insulating portion.

Templates may include wafer, glass, silica, heat-resistant glass, quartz, alumina (Al ₂ O ₃ ), borosilicate glass, zirconia ) Any one of the materials.

The laser irradiated from the upper part of the template passes through the laser through hole and can be irradiated on the welding part of the shield.

After the step (d), the temporary bonding part may be heated, chemically treated, or applied with ultrasonic waves to separate the mask and the template.

The frame may include an edge frame portion and a mask unit sheet portion, and the mask unit sheet portion may include an edge sheet portion; at least one first grid sheet portion extending along the first direction and connected at both ends to the edge A sheet portion; and at least one second grid sheet portion extending in a second direction perpendicular to the first direction and crossing the first grid sheet portion, and both ends are connected to the edge sheet portion.

The mask and the frame may be any one of invar, super invar, nickel, and nickel-cobalt.

In addition, the above object of the present invention is achieved by a frame that is used in a frame-integrated mask in which a plurality of masks are integrally formed with a frame for supporting the mask, wherein the frame includes: an edge frame portion, which Including a hollow area; a mask unit sheet portion, which is provided with a plurality of mask unit areas along at least one of the first direction and the second direction perpendicular to the first direction, and is connected to the edge frame portion, the mask unit sheet A plurality of suction holes are formed in the material portion.

A plurality of suction holes are formed in a portion at a predetermined distance from a corner of the frame where the mask unit area is provided, and the suction holes may be formed in a portion that does not overlap the welding portion of the mask.

The lower part of the frame may also be arranged with a suction part for generating suction pressure.

At least one vacuum channel is formed on the lower support body, and the vacuum channel can transmit the suction pressure generated on the external suction pressure generating device to the suction part.

Invention effect According to the present invention configured as described above, when the mask is adhered to the frame, the deformation of the mask can be prevented and the adhesion between the mask and the frame can be improved.

Furthermore, according to the present invention, the cover and the frame can form an integrated structure.

In addition, according to the present invention, deformation such as sagging or twisting of the mask can be prevented, and alignment can be accurately performed.

In addition, according to the present invention, the manufacturing time can be significantly shortened, and the yield can be significantly increased.

The detailed description of the present invention described later will refer to the accompanying drawings, which show specific embodiments capable of implementing the present invention as examples. These embodiments are described in sufficient detail to enable those skilled in the art to implement the present invention. It should be understood that although the various embodiments of the present invention are different from each other, they are not mutually exclusive. For example, the specific shapes, structures, and characteristics described herein are related to one embodiment, and can be implemented as other embodiments without departing from the spirit and scope of the present invention. In addition, it should be understood that the position or arrangement of individual constituent elements in each disclosed embodiment can be changed without departing from the spirit and scope of the present invention. Therefore, the following detailed description should not be regarded as limiting, and as long as it is properly described, the scope of the present invention is limited only by the scope of the attached patent application and all ranges equivalent thereto. Similar symbols in the drawings represent the same or similar functions in many ways. For convenience, the length, area, thickness, and shape can be exaggerated.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings so that those skilled in the art can easily implement the present invention.

FIG. 1 is a schematic diagram showing a conventional mask for OLED pixel deposition.

Referring to FIG. 1, the existing mask 10 may be manufactured in stick-type or plate-type. The mask 10 shown in (a) of FIG. 1 serves as a strip mask, and both sides of the strip can be welded and fixed to the OLED pixel deposition frame and used. The mask 100 shown in (b) of FIG. 1 can be used as a plate-type (Plate-Type) mask in a large-area pixel formation process.

The body (body or mask film 11) of the mask 10 is provided with a plurality of display units C. One unit C corresponds to one display such as a smartphone. A pixel pattern P is formed in the cell C so as to correspond to each pixel of the display. When the unit C is enlarged, a plurality of pixel patterns P corresponding to R, G, and B are displayed. As an example, a pixel pattern P is formed in the cell C so as to have a resolution of 70×140. That is, a large number of pixel patterns P form a set to constitute one unit C, and a plurality of units C may be formed on the mask 10.

FIG. 2 is a schematic diagram showing a conventional process of bonding the mask 10 to the frame 20. FIG. 3 is a schematic diagram showing that an alignment error between cells occurs during the conventional stretching of the F1 to F2 mask 10. The strip mask 10 including six cells C (C1 to C6) shown in (a) of FIG. 1 will be described as an example.

Referring to (a) of FIG. 2, first, the strip mask 10 should be spread out flat. Tensile forces F1 to F2 are applied along the long axis direction of the strip mask 10, and the strip mask 10 is unfolded as it is stretched. In this state, the strip mask 10 is mounted on the frame 20 in a frame shape. The units C1 to C6 of the strip mask 10 will be located in the blank area inside the frame of the frame 20. The size of the frame 20 may be enough to make the units C1 to C6 of one strip mask 10 located in the blank area inside the frame, or may be enough to make the units C1 to C6 of multiple strip masks 10 located in the blank area inside the frame.

Referring to (b) of FIG. 2, finely adjust the tensile forces F1 to F2 applied to each side of the strip mask 10, and after aligning, as the part of the side surface of the strip mask 10 is welded, the strip mask 10 and the frame 20 are connected to each other. (C) of FIG. 2 shows a side section of the strip mask 10 and the frame connected to each other.

Referring to FIG. 3, although fine adjustments of the stretching forces F1 to F2 applied to the sides of the strip mask 10, the problem is that the mask units C1 to C3 are not well aligned with each other. For example, the distances D1~D1", D2~D2" between the patterns P of the cells C1~C3 are different from each other, or the pattern P is skewed. Since the strip mask 10 has a large area including a plurality (6 cells as an example) of cells C1 to C6 and has a very thin thickness of several tens of μm, it is easy to sag or twist due to load. In addition, it is very difficult to adjust the tensile forces F1 to F2 so that all the cells C1 to C6 are flat, and confirming the alignment state between the cells C1 to C6 with a microscope.

Therefore, a slight error in the stretching forces F1 to F2 may cause an error in the degree of stretching or unfolding of the cells C1 to C3 of the strip mask 10, thereby causing the distance D1 to D1'' between the mask patterns P, D2~D2'' are different. Although it is very difficult to perfectly align so that the error is 0, in order to avoid the mask pattern P having a size of several μm to several tens of μm from adversely affecting the pixel process of the ultra-high-definition OLED, the alignment error is preferably not more than 3 μm. The alignment error between such adjacent units is called pixel position accuracy (PPA).

In addition, approximately 6-20 strip masks 10 are respectively connected to one frame 20, and the alignment between the plurality of strip masks 10 and the plurality of cells C-C6 of the strip mask 10 are simultaneously aligned Precise state is a very difficult task, and can only increase the process time based on alignment, which becomes an important reason for reducing productivity.

On the other hand, after the strip mask 10 is connected and fixed to the frame 20, the tensile forces F1 to F2 applied to the strip mask 10 can act on the frame 20 in the reverse direction. That is, after the strip mask 10 stretched and stretched due to the stretching forces F1 to F2 is connected to the frame 20, it is possible to apply tension to the frame 20. Generally, this tension is not large, and it does not have a great influence on the frame 20, but when the size of the frame 20 is miniaturized and the rigidity becomes low, such tension may slightly deform the frame 20. In this way, a problem may occur that the alignment state between the plurality of cells C to C6 is broken.

In view of this, the present invention proposes a frame 200 and a frame-integrated mask capable of forming the mask 100 and the frame 200 into an integrated structure. The mask 100 integrated with the frame 200 not only prevents deformation such as sagging or twisting, but also can be accurately aligned with the frame 200. When the mask 100 is connected to the frame 200, no tensile force is applied to the mask 100, and therefore, after the mask 100 is connected to the frame 200, no tension may be applied to the mask 200 to cause deformation. Moreover, the present invention has the advantages of significantly reducing the manufacturing time for integrally connecting the mask 100 to the frame 200, and significantly improving the yield.

4 is a front view (FIG. 4(a)) and a side cross-sectional view (FIG. 4(b)) showing a frame-integrated mask according to an embodiment of the present invention, and FIG. 5 is a diagram showing the present invention. A front view ((a) of FIG. 5) and a side cross-sectional view (b of FIG. 5) of the frame according to an embodiment.

4 and 5, the frame-integrated mask may include a plurality of masks 100 and a frame 200. In other words, a plurality of masks 100 are respectively bonded to the frame 200. In the following, for convenience of explanation, a quadrangular mask 100 is taken as an example for description, but before the mask 100 is adhered to the frame 200, it may be a strip mask shape with a protrusion for clamping on both sides, the mask After 100 is bonded to the frame 200, the protrusion can be removed.

A plurality of mask patterns P are formed on each mask 100, and one unit C may be formed in one mask 100. One mask unit C may correspond to one display of a smartphone or the like.

To form a thinner thickness, the mask 100 may be formed by electroforming. Alternatively, the mask 100 may use a sheet produced by rolling. The mask 100 may be an invar steel having a thermal expansion coefficient of about 1.0×10 ⁻⁶ /°C or a super invar material of about 1.0×10 ⁻⁷ /°C. Since the thermal expansion coefficient of the mask 100 of this material is very low, the pattern shape of the mask is less likely to be deformed by thermal energy, and it can be used as a FMM (Fine Metal Mask) or shadow mask in the manufacture of high-resolution OLEDs. Shadow Mask). In addition, considering the recently developed technology for implementing the pixel deposition process within a range where the temperature change value is not large, the mask 100 may also be nickel (Ni), nickel-cobalt (Ni-Co) and other materials with a slightly larger thermal expansion coefficient .

If a rolled film is used, there is a problem that the thickness is greater than the thickness of the plating film formed by electroforming. However, since the coefficient of thermal expansion CTE is low, there is no need to perform an additional heat treatment process, and has the advantages of strong corrosion resistance.

The frame 200 is formed in a form capable of bonding a plurality of masks 100. Including the most peripheral edge, the frame 200 may include a plurality of corners formed along the first direction (eg, lateral direction) and the second direction (eg, vertical direction). Such multiple corners may define an area on the frame 200 for bonding the mask 100.

The frame 200 may include an edge frame portion 210 having a substantially rectangular shape or a square shape. The inside of the edge frame part 210 may have a hollow shape. That is, the edge frame part 210 may include the hollow region R. The frame 200 may be formed of metal materials such as constant steel, super constant steel, aluminum, titanium, etc. In consideration of thermal deformation, it is preferably made of constant steel, super constant steel, nickel, nickel-cobalt with the same thermal expansion coefficient as the mask These materials can be applied to all of the edge frame portion 210 and the mask unit sheet portion 220 that are constituent elements of the frame 200.

In addition, the frame 200 is provided with a plurality of mask unit regions CR, and may include the mask unit sheet portion 220 connected to the edge frame portion 210. The mask unit sheet portion 220 is the same as the mask 100, and can be formed by electroforming, rolling, or by other film forming processes. In addition, the mask unit sheet portion 220 may be connected to the edge frame portion 210 after forming a plurality of mask unit regions CR on a planar sheet by laser scribing, etching, or the like. Alternatively, the mask unit sheet portion 220 may form a plurality of mask unit regions CR by laser scribing, etching, or the like after connecting a planar sheet to the edge frame portion 210. In this specification, the case where the plurality of mask unit regions CR are first formed in the mask unit sheet portion 220 and then connected to the edge frame portion 210 will be described.

The mask unit sheet portion 220 may include an edge sheet portion 221 and at least one of the first grid sheet portion 223 and the second grid sheet portion 225. The edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 refer to portions divided on the same sheet, and they are formed integrally with each other.

The edge sheet part 221 may be substantially connected to the edge frame part 210. Therefore, the edge sheet portion 221 may have a substantially square shape or a square shape corresponding to the edge frame portion 210.

In addition, the first grid sheet portion 223 may be formed to extend along the first direction (lateral direction). The first grid sheet portion 223 is formed in a straight line shape, and both ends thereof may be connected to the edge sheet portion 221. When the mask unit sheet portion 220 includes a plurality of first grid sheet portions 223, each first grid sheet portion 223 preferably has the same pitch.

In addition, further, the second grid sheet portion 225 may be formed to extend along the second direction (vertical direction), the second grid sheet portion 225 is formed in a linear form, and both ends thereof may be connected to the edge sheet portion 221 . The first grid sheet portion 223 and the second grid sheet portion 225 may cross each other perpendicularly. When the mask unit sheet portion 220 includes a plurality of second grid sheet portions 225, each second grid sheet portion 225 preferably has the same pitch.

On the other hand, the pitch between the first grid sheet portions 223 and the pitch between the second grid sheet portions 225 may be the same or different depending on the size of the mask unit C.

Although the first grid sheet portion 223 and the second grid sheet portion 225 have a thin thickness in the form of a thin film, the shape of the cross section perpendicular to the longitudinal direction may be, for example, a rectangular shape, a parallelogram-shaped quadrangular shape, a triangular shape, etc. Part of the sides and corners can be rounded. The cross-sectional shape can be adjusted during laser scribing, etching, etc.

The thickness of the edge frame part 210 may be greater than the thickness of the mask unit sheet part 220. Since the edge frame portion 210 is responsible for the overall rigidity of the frame 200, it can be formed with a thickness of several mm to several cm.

For the mask unit sheet portion 220, the process of manufacturing a thick sheet is actually difficult. If it is too thick, the organic matter source 600 (see FIG. 20) may block the path through the mask 100 in the OLED pixel deposition process. On the contrary, if it is too thin, it may be difficult to ensure sufficient rigidity to support the mask 100. Thus, the mask unit sheet portion 220 is preferably thinner than the thickness of the edge frame portion 210, but thicker than the mask 100. The thickness of the mask unit sheet portion 220 may be about 0.1 mm to 1 mm. In addition, the width of the first grid sheet portion 223 and the second grid sheet portion 225 may be approximately 1 to 5 mm.

In the planar sheet, in addition to the area occupied by the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225, a plurality of mask unit regions CR (CR11 to CR56) may be provided . From another perspective, the mask unit region CR may refer to the hollow region R of the edge frame portion 210 except for the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 A blank area outside the occupied area.

As the cell C of the mask 100 corresponds to the mask cell region CR, it can be substantially used as a channel for depositing pixels of the OLED through the mask pattern P. As described above, one mask unit C corresponds to one display such as a smartphone. A plurality of mask patterns P constituting one cell C may be formed in one mask 100. Alternatively, one mask 100 includes a plurality of cells C and each cell C may correspond to each cell region CR of the frame 200, but in order to accurately align the mask 100, it is necessary to avoid the mask 100 of a large area, preferably one unit C's small area mask 100. Alternatively, one mask 100 having a plurality of cells C may correspond to one cell region CR of the mask 200. At this time, for accurate alignment, it may be considered to correspond to the mask 100 having 2-3 cells C.

The mask 200 includes a plurality of mask unit regions CR, and each mask 100 can be bonded in such a manner that each mask unit C corresponds to each mask unit region CR. Each mask 100 may include a mask unit C in which a plurality of mask patterns P are formed, and a virtual part around the mask unit C (equivalent to a portion of the mask film 110 other than the unit C). The dummy part may include only the mask film 110, or may include the mask film 110 formed with a prescribed dummy pattern in a form similar to the mask pattern P. The mask unit C corresponds to the mask unit region CR of the frame 200, and part or all of the virtual part may be adhered to the frame 200 (mask unit sheet part 220). Thus, the cover 100 and the frame 200 can form an integrated structure.

On the other hand, according to another embodiment, the frame is not manufactured by adhering the mask unit sheet portion 220 to the edge frame portion 210, but may be formed directly in the hollow region R portion of the edge frame portion 210 with the edge frame The portion 210 becomes a frame of an integrated grid frame (corresponding to the grid sheet portions 223 and 225). The frame of this form also includes at least one mask unit region CR, and the mask 100 can be made to correspond to the mask unit region CR to manufacture a frame-integrated mask.

Hereinafter, the manufacturing process of the frame-integrated mask will be described.

First, the frame 200 described in FIGS. 4 and 5 can be provided. FIG. 6 is a schematic diagram showing the manufacturing process of the frame 200 according to an embodiment of the present invention.

Referring to (a) of FIG. 6, an edge frame portion 210 is provided. The edge frame part 210 may have a box shape including a hollow region R.

Next, referring to (b) of FIG. 6, the mask unit sheet portion 220 is manufactured. The mask unit sheet portion 220 uses electroforming, rolling, or other film forming processes to produce a planar sheet, and then the mask unit region CR portion is removed by laser scribing, etching, etc., and can be manufactured. In this specification, an example will be described in which 6×5 mask cell regions CR (CR11 to CR56) are formed. There may be 5 first grid sheet sections 223 and 4 second grid sheet sections 225.

Then, the mask unit sheet portion 220 may correspond to the edge frame portion 210. In the corresponding process, the edge sheet portion 221 and the edge frame portion 210 may be made in a state where all the side portions of the mask unit sheet portion 220 of F1 to F4 are stretched so that the mask unit sheet portion 220 extends flatly correspond. The mask unit sheet portion 220 may be sandwiched and stretched at a plurality of points (1 to 3 points as an example in (b) of FIG. 6) on one side. On the other hand, the unit sheet portion 220 may be stretched by stretching F1 and F2 along a part of the side direction instead of all the sides.

Then, when the mask unit sheet portion 220 corresponds to the edge frame portion 210, the edge sheet portion 221 of the mask unit sheet portion 220 may be bonded by welding W. Preferably, all sides are welded so that the mask unit sheet portion 220 is firmly adhered to the edge frame portion 210. Welding W should be performed as close as possible to the corner side of the frame portion 210 in order to minimize the warping space between the edge frame portion 210 and the mask unit sheet portion 220 and improve the adhesion. The welded W part may be formed in a line or spot shape, has the same material as the mask unit sheet portion 220, and may become an integral unit that connects the edge frame portion 210 and the mask unit sheet portion 220 medium.

7 is a schematic diagram showing a manufacturing process of a frame according to another embodiment of the present invention. The embodiment of FIG. 6 first manufactures the mask unit sheet portion 220 provided with the mask unit region CR, and then adheres to the edge frame portion 210, while the embodiment of FIG. 7 forms the planar sheet material by bonding to the edge frame portion 210. Mask the CR area of the unit area.

First, the edge frame portion 210 including the hollow region R is provided in the same manner as in (a) of FIG. 6.

Then, referring to (a) of FIG. 7, a planar sheet (planar mask unit sheet portion 220') may correspond to the edge frame portion 210. The mask unit sheet portion 220' is a planar state where the mask unit region CR has not yet been formed. In the corresponding process, all the side portions of the mask unit sheet portion 220' of F1 to F4 may be stretched to correspond to the edge frame section 210 in a state where the mask unit sheet portion 220' is extended flatly. On one side, the unit sheet portion 220' can be sandwiched and stretched at a plurality of points (1 to 3 points as an example in (a) of FIG. 7). On the other hand, the unit sheet portion 220' may be stretched by extending F1 and F2 along a part of the side direction instead of all sides.

Then, when the mask unit sheet portion 220' corresponds to the edge frame portion 210, the edge portion of the mask unit sheet portion 220' may be bonded by welding W. Preferably, all sides are welded so that the mask unit sheet portion 220' is firmly adhered to the edge frame portion 220. Welding W should be performed as close as possible to the corner side of the edge frame portion 210 to minimize the warping space between the edge frame portion 210 and the mask unit sheet portion 220', and to improve the adhesion. The welded W part may be formed in a line or spot shape, and has the same material as the mask unit sheet portion 220', and may be formed by connecting the edge frame portion 210 and the mask unit sheet portion 220' as a whole Medium.

Then, referring to (b) of FIG. 7, a mask unit region CR is formed on a planar sheet (planar mask unit sheet portion 220'). The sheet of the mask unit region CR is removed by laser scribing, etching, etc., so that the mask unit region CR can be formed. In this specification, an example will be described in which 6×5 mask cell regions CR (CR11 to CR56) are formed. When the mask unit region CR is formed, the portion welded W to the edge frame portion 210 becomes the edge sheet portion 221, and the mask unit sheet portion 220 can be formed. The mask unit sheet portion 220 includes five first grids The grid sheet portion 223 and the four second grid sheet portions 225.

8 is a schematic diagram showing a conventional mask for forming a high-resolution OLED.

In order to realize a high-resolution OLED, the size of the pattern gradually becomes smaller, and thus the thickness of the mask metal film used needs to be thinner. As shown in (a) of FIG. 8, if high-resolution OLED pixels 6 are to be realized, the pixel pitch, pixel size, etc. are reduced on the mask 10' (PD->PD'). Moreover, in order to prevent uneven deposition of the OLED pixels 6 due to the shadow effect, it is necessary to form 14 the pattern of the mask 10' obliquely. However, with a thickness T1 of about 30-50 mm, in the process of forming the pattern 14 obliquely on the thicker mask 10', it is difficult to perform patterning 13 that matches the fine pixel pitch PD' and the pixel size, so it will become The reason for the poor yield in the processing process. In other words, in order to form the pattern 14 obliquely while having a fine pixel pitch PD', it is necessary to use a mask 10' with a thin thickness.

In particular, in order to achieve high resolution at the UHD level, as shown in FIG. 8(b), only a thin mask 10' with a thickness T2 of about 20 mm or less can be used for fine patterning. Furthermore, in order to achieve ultra-high resolution of UHD or higher, it may be considered to use a thin mask 10' having a thickness T2 of about 10 mm.

9 is a schematic diagram showing a process of manufacturing the mask metal film 100 by electroforming according to an embodiment of the present invention.

Referring to (a) of FIG. 9, a conductive substrate 21 is prepared. In order to perform electroforming, the base material 21 of the mother board may be a conductive material. During electroforming, the mother board can be used as a cathode electrode.

As a conductive material, metal can generate metal oxides on the surface, impurities can flow into the metal manufacturing process, polysilicon substrates can contain inclusions or grain boundaries (Grain Boundary), conductive polymer substrates may contain impurities High performance, and may be weak in strength and acid resistance. Elements such as metal oxides, impurities, inclusions, and grain boundaries that hinder the uniform formation of an electric field on the surface of the motherboard (or cathode) are called "defects". Due to defects, a uniform electric field cannot be applied to the cathode of the above-mentioned material, which may result in uneven formation of a part of the plating film 110 (mask metal film 110).

In ultra-high-quality pixels that achieve UHD level or higher, the unevenness of the coating and the coating pattern (mask pattern P) may have a bad influence on the formation of pixels. For example, the current QHD image quality is 500~600 PPI (pixel per inch), the pixel size reaches about 30~50㎛, 4K UHD, 8K UHD high image quality has higher than the former ~860 PPI, ~1600 PPI Resolution. Directly applicable to micro-displays on VR machines or micro-displays used when plugged into VR machines, the ultra-high image quality of about 2000 PPI or higher is targeted, and the pixel size is about 5~10㎛. The pattern width of the FMM and the shadow mask suitable for it can be formed to a size of several μm to several tens of μm, preferably a size smaller than 30 μm. Therefore, defects with a size of several μm also occupy a large proportion of the size of the pattern size of the mask. In addition, in order to remove the defects of the cathode of the above-mentioned material, an additional process for removing metal oxides, impurities, etc. may be performed, in which process other defects such as etching of the cathode material may be caused.

Therefore, the present invention can use a mother substrate (or cathode) of single crystal material. In particular, it is preferably a single crystal silicon material. The mother board of single crystal silicon material can be doped with a high concentration of 10 ¹⁹ /cm ³ or more in order to have conductivity. The doping may be performed on the entire mother board or only on the surface part of the mother board.

In addition, single crystal materials can use metals such as Ti, Cu, Ag; GaN, SiC, GaAs, GaP, AlN, InN, InP, Ge and other semiconductors; graphite (graphite), graphene (graphene) and other carbon materials; including CH ₃ superconductor _{NH 3 PbCl 3, CH 3 NH} 3 PbBr 3, CH 3 NH 3 PbI 3, SrTiO 3 , etc. perovskite (Transition of perovskite) single crystal ceramic structure; aircraft parts and the like with the single crystal superalloy. Metal and carbon materials are basically conductive materials. In the case of semiconductor materials, in order to have conductivity, a high concentration doping of 10 ¹⁹ /cm ³ or more can be performed. Other materials can form conductivity by performing doping or forming oxygen vacancy. The doping may be performed on the entire mother board or only on the surface part of the mother board.

Since the single crystal material has no defects, a uniform electric field is formed on the entire surface during electroforming, so a uniform metal film 110 is generated. The frame-integrated masks 100 and 200 manufactured by a uniform metal film can further improve the image quality of OLED pixels. In addition, since there is no need to perform additional processes for removing and eliminating defects, process costs can be reduced and productivity can be improved.

The following description assumes that a single crystal silicon wafer is used as the conductive substrate 21.

Referring again to (a) of FIG. 9, the conductive substrate 21 is then used as a motherboard [cathode (cathode body)], and the anode (not shown) is spaced apart, so that the conductive substrate 21 The metal film 110 [or plated film 110] is formed by electroforming. The mask metal film 110 may be formed on the exposed upper surface and side surfaces of the conductive substrate 21, which is disposed opposite to the anode and may apply an electric field. The metal film 110 may be formed not only on the side surface of the conductive base material 21 but also on a part of the lower surface of the conductive base material 21.

Then, the edge portion of the D mask metal film 110 is cut with laser or a photoresist layer is formed on the top of the mask metal film 110, and only a part of the mask metal film 110 exposed by D is etched and removed. As a result, as shown in FIG. 9( b ), the mask metal film 110 can be separated from the conductive substrate 21.

In addition, before the mask metal film 110 is separated from the conductive substrate 21, heat treatment H may be performed. The present invention is characterized by reducing the thermal expansion coefficient of the mask 100 and separating the mask metal film from the conductive substrate 21 [or motherboard, cathode] in order to prevent the heat-induced deformation of the mask 100 and the mask pattern P Before 110, heat treatment H is performed. The heat treatment can be performed at a temperature of 300°C to 800°C.

Generally, the thermal expansion coefficient of a constant-fan steel sheet produced by electroforming is higher than that of a constant-fan sheet produced by rolling. Therefore, the thermal expansion coefficient can be reduced by heat treatment of the Hengfan steel sheet, but during the heat treatment, the Hengfan steel sheet will peel off and deform. This is because the heat treatment is performed only on the Hengfan steel sheet or the Hengfan steel sheet temporarily bonded only on the upper surface of the conductive substrate 21. However, in the present invention, since the mask metal film 110 is formed not only on the upper surface of the conductive base material 21 but also on a part of the side surface and the lower surface, peeling, deformation, and the like do not occur even if the heat treatment H is performed. In other words, since the heat treatment is performed in a state where the conductive base material 21 and the mask metal film 110 are closely adhered, there is an advantage that the heat treatment can be stably performed while preventing peeling, deformation, etc. caused by the heat treatment.

FIG. 10 is a schematic diagram showing a process of manufacturing the mask metal film 100 by rolling according to an embodiment of the present invention.

First, the mask metal film 110 may be prepared. As an example, the mask metal film 110 may be prepared by rolling.

Referring to (a) of FIG. 10, a metal sheet produced by a rolling process can be used as the mask metal film 110'. The metal sheet produced based on the rolling process may have a thickness of tens to hundreds of mm in the manufacturing process. As shown in FIG. 8 described above, in order to achieve high resolution at UHD level, only thinner mask metal film 110 with a thickness of about 20 mm or less can be finely patterned. In order to achieve ultra-high UHD or higher For high resolution, it is necessary to use a thin mask metal film 110 with a thickness of about 10 mm. However, the mask metal film 110' generated by the rolling process has a thickness of about 25 to 500 mm, so it is necessary to make the thickness thinner.

Therefore, a process of flattening PS on one side of the mask metal film 110' can also be performed. Here, the flattening PS means mirroring one side (upper surface) of the mask metal film 110' and removing a part of the upper part of the mask metal film 110' to reduce the thickness. The flattening PS can be performed by a CMP (Chemical Mechanical Polishing) method, and as long as it is a well-known CMP method, it can be used without particular limitation. Furthermore, the thickness of the mask metal film 110' can be reduced by chemical wet etching or dry etching methods. In addition to this, other processes that can make the thickness of the mask metal film 110' thinner and flattenable can also be used, and there is no particular limitation.

In the process of performing the flattening of PS, as a row, during the CMP process, the surface roughness Ra of the upper surface of the mask metal film 110' can be controlled. Preferably, the mirror surface can be further reduced in surface roughness. Or, as another example, after planarizing the PS based on the chemical wet etching or dry etching process, a polishing process such as an individual CMP process may be additionally performed to reduce the surface roughness Ra.

In this way, the thickness of the mask metal film 110' can be reduced to about 50 mm or less. By this, the thickness of the mask metal film 110 is preferably about 2㎛ to 50㎛, and more preferably, the thickness may be about 5㎛ to 20㎛. However, it is not limited to this.

Referring to FIG. 10(b), which is the same as FIG. 10(a), the mask metal film 110 can be manufactured by reducing the thickness of the mask metal film 110' manufactured by the rolling process. However, in the state where the mask metal film 110' is bonded by interposing the temporary bonding portion 55 on the template 50 described later, the flattening PS process is performed to reduce the thickness.

11 to 12 are schematic diagrams showing a process of bonding the mask metal film 110 to the template 50 and forming the mask 100 to manufacture a mask support template according to an embodiment of the present invention.

Referring to (a) of FIG. 11, a template 50 (template) may be provided. The template 50 is a medium that moves with the mask 100 attached and supported on one side of the template 50. One side of the template 50 is preferably flat to support and move the flat mask 100. The center portion 50 a corresponds to the mask unit C that masks the metal film 110, and the edge portion 50 b may correspond to the dummy portion DM of the mask metal film 110. The template 50 may have a large flat plate size larger than the mask metal film 110 so that the mask metal film 110 is supported as a whole.

The template 50 is preferably made of a transparent material, so that the process of aligning and adhering the mask 100 and the frame 200 is convenient for visual observation and the like. Furthermore, if it is a transparent material, it is also possible to penetrate the laser. As a transparent material, glass, silica, heat-resistant glass, quartz, alumina (Al ₂ O ₃ ), borosilicate glass, zirconia, etc. can be used material. As an example, for the template 50, BOROFLOAT ^® 33 material having excellent heat resistance, chemical durability, mechanical strength, transparency, etc. in borosilicate glass can be used. Moreover, the thermal expansion coefficient of BOROFLOAT ^® 33 is about 3.3, which has little difference from the thermal expansion coefficient of the Hengfan steel mask metal film 110, and has the advantage of facilitating control of the mask metal film 110.

In addition, the side of the template 50 that is in contact with the mask metal film 110 may be a mirror surface, so that no air gap is generated between the interface with the mask metal film 110 [or the mask 100]. Based on this, the surface roughness Ra of one side of the template 50 may be 100 nm or less. In order to realize the template 50 having a surface roughness Ra of 100 nm or less, a wafer may be used for the template 50. The surface roughness Ra of the wafer is about 10 nm, and there are many products on the market. The surface treatment process is already known, so it can be used as the template 50. The surface roughness Ra of the template 50 is on the order of nm, so there is no gap AG or almost no gap AG, and it is easy to generate a welding bead WB based on laser welding, so there is no influence on the alignment error of the mask pattern P.

The template 50 may be formed with a laser penetrating hole 51 so that the laser L irradiated from the upper portion of the template 50 reaches the welding portion (the area where welding is performed) of the mask 100. The laser penetrating holes 51 can be formed on the template 50 according to the positions and the number of welded portions. A plurality of welded portions may be arranged at predetermined intervals on the edge of the mask 100 or a portion of the dummy portion DM [refer to (e) of FIG. 12 ]. Therefore, a plurality of laser through holes 51 may be formed at a predetermined interval corresponding thereto. As an example, the welded portions are arranged at predetermined intervals on the virtual portions DM on both sides (left/right) of the mask 100, so the laser through holes 51 may also be disposed at predetermined intervals on both sides (left/right) of the template 50 Form multiple.

The laser through hole 51 does not necessarily correspond to the position and number of welded parts. For example, only a part of the laser penetration hole 51 may be irradiated with laser L to perform welding. In addition, a part of the laser through hole 51 that does not correspond to the welded portion may be used instead of the alignment mark when the mask 100 and the template 50 are aligned. If the material of the template 50 is transparent to the laser L light, the laser through hole 51 may not be formed.

The temporary bonding portion 55 may be formed on one surface of the template 50. The temporary bonding portion 55 may be formed on the entire surface of the template 50. The mask 100 [mask metal film 110] can be bonded on the entire temporary bonding portion 55. Before the mask 100 is bonded to the frame 200, the temporary bonding portion 55 temporarily bonds the mask 100 [or the mask metal film 110] to one side of the template 50 and supports it on the template 50.

The temporary adhesive part 55 may use an adhesive or an adhesive sheet that can be separated by heating, and an adhesive or an adhesive sheet that can be separated by UV irradiation.

As an example, liquid wax can be used for the temporary bonding portion 55. As the liquid wax, the same wax as that used in the semiconductor wafer polishing step or the like can be used, and the kind is not particularly limited. The liquid wax mainly contains substances such as acrylic acid, vinyl acetate, nylon, and various polymers and solvents as resin components for controlling adhesion and impact resistance related to the holding force. As an example, as the resin component, acrylonitrile-butadiene rubber (ABR, Acrylonitrile butadiene rubber) can be used as the temporary bonding part 55, and SKYLIQUID ABR-4016 containing n-propanol can be used as the solvent component. The liquid wax can be formed on the temporary bonding portion 55 using spin coating.

The temporary bonding part 55 as a liquid wax has a lower viscosity at a temperature higher than 85°C to 100°C, and a higher viscosity at a temperature lower than 85°C, a part of it becomes hard like a solid, and can make the mask The cover metal film 110 is fixed and adhered to the template 50.

Then, referring to (b) of FIG. 11, the mask metal film 110' can be adhered to the template 50. After heating the liquid wax above 85°C and bringing the mask metal film 110' into contact with the template 50, the mask metal film 110' and the template 50 are passed between the rollers for bonding.

According to an embodiment, the template 50 is baked at a temperature of about 120° C. for 60 seconds to vaporize the solvent of the temporary bonding portion 55 and directly perform the lamination process of the mask metal film. The lamination can be performed by loading the mask metal film 110' on the template 50 with the temporary bonding portion 55 formed on one side, and passing it between an upper roll of about 100°C and a lower roll of about 0°C. As a result, the mask metal film 110' can be brought into contact by interposing the temporary bonding portion 55 on the template 50.

13 is a schematic view showing an enlarged cross-section of the temporary bonding portion 55 according to an embodiment of the present invention. As yet another example, a thermal release tape can be used for the temporary bonding portion 55. The thermal separation tape is a base film 56 with a PET film or the like arranged in the middle, and thermally separable adhesive layers 57a, 57b (thermal release adhesive) are arranged on both sides of the base film 56, and the outer contours of the adhesive layers 57a, 57b can be arranged with separation Film/release film 58a, 58b. Among them, the separation temperatures of the adhesive layers 57a and 57b disposed on both sides of the base film 56 may be different from each other.

According to an embodiment, in a state where the separation film/release film 58a, 58b is removed, the lower surface of the thermal separation tape [the second adhesive layer 57b] is adhered to the template 50, and the upper surface of the thermal separation tape [the first adhesive layer 57a] Can be adhered to the mask metal film 110'. The separation temperatures of the first adhesive layer 57a and the second adhesive layer 57b are different from each other. Therefore, in FIG. 18 described later, when the template 50 is separated from the mask 100, as the first adhesive layer 57a is heated, the mask 100 It can be separated from the template 50 and the temporary bonding portion 55.

Next, referring further to FIG. 11(b), one side of the mask metal film 110' can be flattened PS. As described above, the mask metal film 110' made by the rolling process in FIG. 10 can be reduced in thickness (110'->110) by the planarizing PS process. Moreover, the mask metal film 110 made by the electroforming process can also be subjected to a planarization PS process to control its surface characteristics and thickness.

Thereby, as shown in FIG. 11(c), as the thickness of the mask metal film 110' decreases (110'->110), the thickness of the mask metal film 110 becomes approximately 5 mm to 20 mm.

In addition, when the mask metal film 110 is formed by electroforming, the flattening PS step of (b) of FIG. 11 can be omitted, and the process of bonding the mask metal film 110 to the template 50 can be directly performed to form the (c of FIG. 11 )status.

Then, referring to (d) of FIG. 12, a patterned insulating portion 25 may be formed on the mask metal film 110. The insulating portion 25 can be formed of a photoresist material using a printing method or the like.

Next, the mask metal film 110 may be etched. Methods such as dry etching and wet etching may be used, and the method is not particularly limited. As a result of the etching, the portion of the mask metal film 110 exposed on the empty space 26 between the insulating portions 25 is etched. The etched portion of the mask metal film 110 constitutes the mask pattern P, whereby the mask 100 formed with a plurality of mask patterns P can be manufactured.

Then, referring to FIG. 12(e), by removing the insulating portion 25, the manufacture of the template 50 supporting the mask 100 can be completed. The mask 100 may include a mask unit C formed with a plurality of mask patterns P and a dummy part DM around the mask unit C. 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 a mask formed with a predetermined dummy portion pattern similar in shape to the mask pattern P盖膜110。 The cover film 110. The dummy portion DM corresponds to the edge of the mask 100, so part or all of the dummy portion DM can be adhered to the frame 200 [mask unit sheet portion 220].

The width of the mask pattern P may be less than 40 μm, and the thickness of the mask 100 may be about 2-50 μm.

Since the frame 200 includes a plurality of mask unit regions CR (CR11 to CR56), a plurality of masks having mask units C (C11 to 56) corresponding to the respective mask unit regions CR (CR11 to CR56) may be formed. Hood 100. Furthermore, a plurality of templates 50 that respectively support a plurality of masks 100 may be provided.

14 is a schematic diagram showing a process of loading a mask support template on a frame according to an embodiment of the present invention.

Referring to FIG. 14, the template 50 can be transferred by the vacuum chuck 90. The surface opposite to the surface of the template 50 to which the mask 100 is bonded is sucked by the vacuum chuck 90 and transferred. The vacuum chuck 90 may be connected to moving means (not shown) that moves to the x, y, z, and θ axes. In addition, the vacuum chuck 90 can attract the template 50 and be connected to flip means (not shown) capable of flipping. As shown in FIG. 14( b ), the vacuum chuck 90 does not affect the bonding state and the alignment state of the mask 100 even when the template 50 is sucked and turned over and transferred to the frame 200.

15 is a schematic diagram showing a state in which a template is mounted on a frame so that a mask corresponds to a unit area of the frame according to an embodiment of the present invention. FIG. 16 is a schematic diagram showing a state in which the suction force VS is applied to the mask through the suction hole 229 according to an embodiment of the present invention. FIG. 17 is a partial schematic diagram showing a frame 200 having a plurality of suction holes 229 according to an embodiment of the present invention. FIG. 15 shows an example in which one mask 100 is associated with/bonded to the unit area CR, but multiple masks 100 may be simultaneously corresponding to all unit areas CR to make the mask 100 adhere to the frame 200. process. At this time, there may be a plurality of templates 50 for supporting the plurality of masks 100, respectively. In addition, although FIG. 16 shows the form in which the suction holes 229 are formed in the first grid sheet portion 223 to apply the suction force VS, of course, the suction holes 229 may be formed in the edge sheet portion 221 and the edge sheet A predetermined step is formed between the portion 221 and the edge frame portion 210, whereby the suction force VS is applied to the suction hole 229 of the edge sheet portion 221.

Then, referring to FIG. 15, the mask 100 may correspond to one mask cell region CR of the frame 200. Correspondence between the mask 100 and the mask unit area CR can be achieved by loading the template 50 on the frame 200 [or the mask unit sheet portion 220]. While controlling the position of the template 50/vacuum chuck 90, observe with a microscope whether the mask 100 corresponds to the mask unit area CR. Since the template 50 presses the mask 100, the mask 100 and the frame 200 can tightly abut.

In addition, the present invention is characterized in that no gaps are generated between the interface of the mask 100 and the frame 200, and in order to make them more closely contact, in addition to the load of the template 50, the suction force VS is used. As a path for applying suction force VS or suction pressure, a plurality of suction holes 229 may be formed in the frame 200.

15 to 17, a plurality of suction holes 229 may be formed near the corner of the frame 200 having the mask unit area CR. Specifically, a plurality of suction holes 229 may be formed at a predetermined distance from the corner of the mask unit sheet portion 220, and more specifically, at a predetermined distance from the inner corner of the edge sheet portion 221 The portion and the corners of the first and second grid sheet portions 223 and 225 are separated by a predetermined distance.

The shape, size, etc. of the plurality of suction holes 229 are not particularly limited as long as they are within a range where vacuum suction pressure can be applied. However, it is preferable that the positions of the plurality of suction holes 229 do not overlap with the welding portion (the area to be welded) of the mask 100. If the welding part overlaps the suction hole 229, the mask 100 and the frame 200 [or the mask unit sheet part 220] will not be in close contact, so the welding bead WB by laser welding cannot be smoothly generated. Preferably, a plurality of suction holes 229 are formed in a portion close to the welded portion, so that the welded portion of the mask 100 is more closely connected to the frame 200 [or the mask unit sheet portion 220].

As shown in FIG. 16, if the template 50 is mounted on the frame 200 [or the mask unit sheet portion 220], a part of the lower surface of the mask 100 and the upper part of the frame 200 [or the mask unit sheet portion 220] Abut. The upper part of the suction hole 229 formed on the frame 200 [or the mask unit sheet part 220] corresponds to the lower surface of the mask 100, and the suction force (suction pressure) application means corresponding to the lower part of the suction hole 229 is applied by the suction hole 229 applies the suction force VS [or suction pressure VS] to the mask 100, thereby pulling the portion of the mask 100 corresponding to the suction hole 229. As a result, the mask 100 will be more tightly connected to the frame 200, so that when performing laser welding, the welding bead WB can be generated more stably.

As the means for applying the suction force (suction pressure), a known device that performs vacuum suction in the suction hole 229 can be used. However, in the following embodiment, the lower support 70 including the suction portion 75 will be described.

Referring to FIGS. 15 and 16, a lower support 70 may also be arranged in the lower part of the frame 200. The lower support body 70 may be arranged on a table portion (not shown) as a mounting table that performs a bonding process of the mask 100 and the frame 200 and supports the lower portion of the frame 200. The lower support 70 may be arranged at the lower part of the frame 200, and during the process of bonding the mask 100 to the frame 200, to be fixedly connected to the frame 200, the lower support 70 may be arranged at the lower part of the frame 200. The lower support body 70 may have a plate shape to support the frame 200, and its size may be less than or equal to the area of the frame 200. Alternatively, the lower support 70 may have a size capable of entering the inside of the hollow region R of the frame edge portion 210 and have a flat plate shape. In consideration of the coefficient of thermal expansion, the lower support 70 preferably uses the same material as the frame 200, but a material with high rigidity may be used. Furthermore, a predetermined support groove (not shown) corresponding to the shape of the mask unit sheet portion 220 may be formed on the upper surface of the lower support 70. At this time, the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 are inserted into the support grooves, so that the mask unit sheet portion 220 is better fixed.

An adsorption portion 75 may be formed on the upper portion of the lower support 70. The suction portion 75 is preferably arranged to correspond to the position of the suction hole 229 formed on the frame 200 [or the mask unit sheet portion 220]. In other words, the suction portion 75 may be arranged at a position where the suction force VS [or suction pressure VS] is collectively applied to the suction hole 229 on the lower support 70. The suction unit 75 can use a known vacuum suction device, and can be connected to an external suction pressure generating device. As an example, a vacuum channel 76 is formed inside the lower support 70, the other end is connected to an external suction pressure generating device (not shown) such as a pump, and one end is connected to the suction portion 75. A plurality of holes, grooves, etc. are formed on the upper surface of the suction part 75 connected to the vacuum channel 76, and can be used as a channel for applying suction pressure. The external suction pressure generating device is connected to the plurality of vacuum channels 76 of the lower support 70, whereby the suction pressure to each vacuum channel 76 can be controlled separately, and the suction pressure to all vacuum channels 76 can also be controlled at the same time.

The lower support 70 may press the opposite surface of the mask unit region CR that is in contact with the mask 100. That is, the lower support 70 supports the mask unit sheet portion 220 in the upper direction, thereby preventing the mask unit sheet portion 220 from sagging downward when the mask 100 is bonded. At the same time, the lower support 70 and the template 50 press the edge of the mask 100 and the frame 200 [or the mask unit sheet portion 220] in opposite directions, so that the alignment state of the mask 100 is not destroyed It stays aligned.

Further, the suction force VS [or suction pressure VS] is supplied from the suction portion 75 of the lower support 70, and as the suction force VS is applied to the mask 100 through the suction hole 229, the mask 100 will be pulled to the suction Part 75 side (lower side). As a result, the interface between the mask 100 and the frame 200 [or the mask unit sheet portion 220] will be in close contact.

Since the suction part 75 strongly pulls the mask 100, there is no fine gap between the interface of the mask 100 and the frame 200. As a result, since the mask 100 is in close contact with the frame 200 [the first grid sheet portion 223 in the enlarged view of FIG. 16 ], even if the laser L is irradiated at any position of the welded portion, between the mask 100 and the frame 200 It is also easy to generate welding beads WB. The welding bead WB connects the mask 100 and the frame 200 as a whole, and as a result, has the advantage of stably performing welding.

In addition, since the process of matching the mask 100 to the mask unit region CR of the frame 200 can be completed only by attaching the mask 100 to the template 50 and loading the template 50 on the frame 200, this process can be used for the mask 100 No stretching force is applied.

After the suction force VS of the suction part 75 is applied, the mask 100 is irradiated with laser light L, so that the mask 100 is bonded to the frame 200 by laser welding. The welding portion of the mask welded by the laser generates a welding bead WB. The welding bead WB may have the same material as the mask 100/frame 200 and be integrated with the mask 100/frame 200.

18 is a schematic diagram showing a process of separating the mask 100 and the template 50 after bonding the mask 100 to the frame 200 according to an embodiment of the present invention.

Referring to FIG. 18, after the mask 100 is adhered to the frame 200, the mask 100 and the template 50 can be debonded. The separation between the mask 100 and the template 50 can be achieved by at least one of heating the ET of the temporary bonding portion 55, chemical treatment CM, applying ultrasonic waves US, and applying UV. Since the mask 100 maintains the state of being adhered to the frame 200, it is possible to lift only the template 50. As an example, if a thermal ET higher than 85° C. to 100° C. is applied, the viscosity of the temporary bonding portion 55 decreases, and the adhesive force between the mask 100 and the template 50 is weak, so the mask 100 and the template 50 can be separated. As another example, the temporary bonding part 55 is immersed in a chemical substance such as IPA, acetone, ethanol, etc., and the mask 100 and the template 50 are separated by dissolving and removing the temporary bonding part 55 and the like. As yet another example, if ultrasonic waves US or UVUV are applied, the adhesion between the mask 100 and the template 50 becomes weak, so the mask 100 and the template 50 can be separated.

Further, since the temporary bonding portion 55 for bonding the mask 100 and the template 50 is a TBDB bonding material (temporary bonding & debonding adhesive), various debonding methods can be used.

As an example, a Solvent Debonding method based on chemical treatment CM can be used. The penetration of the solvent causes the temporary adhesive portion 55 to dissolve to achieve peeling. At this time, since the pattern P is formed on the mask 100, the solvent will permeate through the mask pattern P and the interface between the mask 100 and the template 50. Solvent stripping can be performed at room temperature and does not require other complicated stripping equipment, so it is economical compared to other stripping methods.

As yet another example, a heat debonding method based on heated ET may be used. The high-temperature heat induces the decomposition of the temporary bonding portion 55, and if the adhesive force between the mask 100 and the template 50 becomes small, it can be peeled in the up-down direction or the left-right direction.

As yet another example, a peeling (Peelable Adhesive Debonding) method based on a peeling adhesive by heating ET, applying UVUV, or the like can be used. If the temporary adhesive part 55 is a thermal separation tape, it can be peeled by a peeling method of peeling the adhesive, which is the same as the thermal peeling method, does not require high-temperature heat treatment and expensive heat treatment equipment, and the process is relatively simple.

As yet another example, a room temperature debonding method based on chemical treatment CM, application of ultrasonic waves US, application of UVUV, etc. may be used. If a part (center part) of the mask 100 or the template 50 is non-sticky, only the edge part is bonded by the temporary bonding part 55. In addition, the solvent penetrates the edge portion during peeling, so peeling can be achieved by dissolving the temporary bonding portion 55. This method has the following advantages: during the process of bonding and peeling, the remaining parts except the edge regions of the mask 100 and the template 50 will not be directly damaged or defects caused by the residue of the bonding material during peeling. Moreover, this method is different from the thermal peeling method, and since there is no need to perform a high-temperature heat treatment process during peeling, it has the advantage that the process cost can be relatively reduced.

FIG. 19 is a schematic diagram showing a state where the mask 100 is bonded to the frame 200 according to an embodiment of the present invention.

Referring to FIG. 19, a mask 100 may be adhered to a unit area CR of the frame 200.

Since the mask unit sheet portion 220 of the frame 200 has a thin thickness, when a tensile force is applied to the mask 100, when the mask unit sheet portion 220 is adhered to the mask unit sheet 220, the tensile force remaining in the mask 100 acts The mask unit sheet portion 220 and the mask unit region CR may be deformed. Therefore, the mask 100 should be adhered to the mask unit sheet portion 220 in a state where no stretching force is applied to the mask 100. The present invention can complete the process of matching the mask 100 to the mask unit area CR of the frame 200 by only attaching the mask 100 to the template 50 and loading the template 50 on the frame 200. This process does not apply to the mask 100 Any stretching force. Thereby, it is possible to prevent deformation of the frame 200 (or the mask unit sheet portion 220) due to the tensile force applied to the mask 100 acting as a tension on the frame 200 in reverse.

The existing mask 10 of FIG. 1 includes 6 units C1 to C6, and thus has a longer length, while the mask 100 of the present invention includes one unit C, and thus has a shorter length, so PPA (pixel position accuracy) is distorted The degree will become smaller. Assuming that the length of the mask 10 including a plurality of cells C1 to C6,... Is 1 m, and a PPA error of 10 μm occurs in the total length of 1 m, the mask 100 of the present invention can be reduced with the relative length (equivalent to a cell The number of C decreases) and the above error range is 1/n. For example, the length of the mask 100 of the present invention is 100 mm, it has a length reduced from 1 m of the existing mask 10 to 1/10, so a PPA error of 1 μm occurs in the total length of 100 mm, which significantly reduces the alignment error .

On the other hand, the mask 100 includes a plurality of cells C. Even if each cell C corresponds to each cell region CR of the frame 200, and the alignment error is still within a minimum range, the mask 100 may The mask unit area CR corresponds. Alternatively, the mask 100 having a plurality of cells C may correspond to one mask cell region CR. In this case, considering the process time and productivity based on the alignment, the mask 100 is preferably provided with as few cells C as possible.

As far as the present invention is concerned, it is only necessary to match one unit C of the mask 100 and confirm the alignment state, so compared with the existing method that simultaneously matches a plurality of units C (C1 to C6) and needs to confirm all alignment states , Can significantly shorten the manufacturing time.

That is, the manufacturing method of the frame-integrated mask of the present invention can significantly shorten the time compared with the conventional method. In the conventional method, the cells C11 to C16 included in the six masks 100 are respectively connected to one cell region CR11 to CR16 6 processes corresponding to and confirming each alignment state, matching 6 cells C1~C6 at the same time, and it is necessary to confirm the alignment state of 6 cells C1~C6 at the same time.

In addition, in the manufacturing method of the frame-integrated mask of the present invention, the product yield in the process of aligning 30 masks 100 with 30 unit regions CR (CR11 to CR56) and aligning them 30 times will be obvious It is higher than the yield of the existing product in the process of aligning 5 masks 10 (refer to (a) of FIG. 2) including 6 units C1 to C6 to the frame 20 and aligning them 5 times. Since the existing method of aligning 6 cells C1 to C6 in an area corresponding to 6 cells C at a time is obviously cumbersome and difficult work, the product yield is low.

In addition, in step (b) of FIG. 11, as described above, when the mask metal film 110 is bonded to the template 50 by a lamination process, a temperature of about 100° C. is applied to the mask metal film 110. Based on this, the mask metal film 110 is adhered to the template 50 with a part of the tensile force applied. After that, the mask 100 is bonded to the frame 200. If the mask 100 is separated from the template 50, the mask 100 will shrink by a predetermined degree.

When each mask 100 is adhered to the corresponding mask unit region CR, and the template 50 is separated from the mask 100, the plurality of masks 100 apply tension that contracts in the opposite direction, so this force is offset, so The mask unit sheet portion 220 is not deformed. For example, in the first grid sheet portion 223 between the mask 100 attached to the CR11 unit area and the mask 100 attached to the CR12 unit area, the first grid sheet portion 223 acts on the right side of the mask 100 attached to the CR11 unit area The tension and the tension acting in the left direction of the mask 100 attached to the CR12 cell area cancel each other out. Thereby, the deformation of the frame 200 [or the mask unit sheet portion 220] based on the tension is minimized, and the alignment error of the mask 100 [or the mask pattern P] can be minimized.

FIG. 20 is a schematic diagram showing an OLED pixel deposition apparatus 1000 using frame-integrated masks 100 and 200 according to an embodiment of the present invention.

Referring to FIG. 20, the OLED pixel deposition apparatus 1000 includes: a magnetic plate 300 that houses the magnet 310 and cooling water pipes 350 are arranged; and a deposition source supply part 500 that supplies the organic matter source 600 from the lower portion of the magnetic plate 300.

A target substrate 900 such as glass for depositing the organic matter source 600 may be interposed between the magnetic plate 300 and the deposition source supply part 500. The target substrate 900 may be provided with frame-integrated masks 100, 200 [or FMM] for depositing the organic matter source 600 in different pixels in a close or very close manner. The magnet 310 can generate a magnetic field and adhere to the target substrate 900 by the magnetic field.

The deposition source supply part 500 can travel back and forth and supply the organic matter source 600, and the organic source 600 supplied by the deposition source supply part 500 can be deposited on one side of the target substrate 900 through the pattern P formed on the frame-integrated masks 100, 200 . The organic matter source 600 deposited after the pattern P of the frame-integrated masks 100 and 200 can be used as the pixel 700 of the OLED.

In order to prevent uneven deposition of the pixel 700 due to the shadow effect, the pattern of the frame-integrated masks 100 and 200 may be formed obliquely [or formed with a tapered S]. The organic matter source 600 passing the pattern in the diagonal direction along the inclined surface can also contribute to the formation of the pixel 700, and therefore, the pixel 700 can be deposited with a uniform thickness as a whole.

At a first temperature higher than the temperature of the pixel deposition process, the mask 100 is adhesively fixed on the frame 200, so even if it is raised to the temperature used for the pixel deposition process, it hardly affects the position of the mask pattern P. The mask The PPA between 100 and the adjacent mask 100 can be maintained to not exceed 3 μm.

As described above, the present invention lists preferred embodiments for illustration and description, but it is not limited to the above-mentioned embodiments, and various modifications and changes can be made by those having ordinary knowledge in the technical field without departing from the spirit of the present invention. Such modifications and changes fall within the scope of the present invention and the attached patent application.

6: pixels 10: Strip mask 10’: Mask 11: Mask film 13: Patterning 14: Pattern 20: Frame 21: conductive substrate 26: empty position 50: template 50a: Center 50b: Edge 51: Laser through hole 55: Temporary bonding section 56: basement membrane 57a, 57b: adhesive layer 58a, 58b: separation membrane/release membrane 70: lower support 75: Adsorption section 76: vacuum channel 90: Vacuum suction cup 100: mask 110: mask film 110’: Mask metal film 200: frame 210: Edge frame part 220, 220’: Sheet unit of mask unit 221: Edge sheet section 223: First grid sheet section 225: Second grid sheet section 229: Adsorption hole 300: magnetic board 310: with magnet 350: cooling water pipe 500: deposition source supply department 600: Organic source 700: pixels 900: target substrate 1000: OLED pixel deposition device AG: gap C: Unit, mask unit C1~C6: unit CM: Chemical treatment CR (CR11~CR56): mask unit area DM: Dummy Department, Mask Dummy Department D1~D1'', D2~D2'': distance D: Laser cutting ET: heating F1~F2: Stretch H: Heat treatment L: Laser R: Hollow area of the edge frame Ra: Surface roughness P: Mask pattern PS: Flatten PD: Reduce pixel pitch PD': pixel pitch VS: apply suction force, suction pressure US: applying ultrasound UV: Apply UV W: welding WB: Welding welding beads S: formed obliquely; tapered T1, T2: thickness

FIG. 1 is a schematic diagram showing a conventional mask for OLED pixel deposition.

FIG. 2 is a schematic diagram showing a conventional process of bonding a mask to a frame.

FIG. 3 is a schematic diagram showing that an alignment error between cells occurs during a conventional stretching mask.

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

5 is a front view and a side cross-sectional view showing a frame according to an embodiment of the present invention.

6 is a schematic diagram showing a manufacturing process of a frame according to an embodiment of the present invention.

7 is a schematic diagram showing a manufacturing process of a frame according to another embodiment of the present invention.

8 is a schematic diagram showing a conventional mask for forming a high-resolution OLED.

9 is a schematic diagram showing a process of manufacturing a mask metal film by electroforming according to an embodiment of the present invention.

10 is a schematic diagram showing a process of manufacturing a mask metal film by rolling according to an embodiment of the present invention.

11 to 12 are schematic diagrams showing a process of bonding a mask metal film to a template and forming a mask to manufacture a mask support template according to an embodiment of the present invention.

13 is a schematic view showing an enlarged cross-section of a temporary bonding portion according to an embodiment of the present invention.

14 is a schematic diagram showing a process of loading a mask support template on a frame according to an embodiment of the present invention.

15 is a schematic diagram showing a state in which a template is mounted on a frame so that a mask corresponds to a unit area of the frame according to an embodiment of the present invention.

16 is a schematic diagram showing a state in which a suction force is applied to a mask through a suction hole according to an embodiment of the present invention.

17 is a partial schematic diagram showing a frame in which a plurality of suction holes are formed according to an embodiment of the present invention.

18 is a schematic diagram showing a process of separating a mask and a template after bonding the mask to the frame according to an embodiment of the present invention.

FIG. 19 is a schematic diagram showing a state in which a mask is adhered to a frame according to an embodiment of the present invention.

20 is a schematic diagram showing an OLED pixel deposition apparatus using a frame-integrated mask according to an embodiment of the present invention.

50: template

51: Laser through hole

55: Temporary bonding section

70: lower support

75: Adsorption section

76: vacuum channel

90: target substrate

100: mask

223: First grid sheet section

229: Adsorption hole

VS: apply suction force, suction pressure

WB: Welding welding beads

L: Laser

Claims (20)

A method for manufacturing a frame-integrated mask, which integrates at least one mask with a frame for supporting the mask, wherein the method includes the following steps: (a) Provide a frame with at least one mask unit area; (b) Provide a mask; (c) Make the mask correspond to the mask unit area of the frame; and (d) irradiate laser on the welding part of the mask to make the mask adhere to the frame, A plurality of suction holes are formed in a portion at a predetermined distance from the corner of the frame where the mask unit area is provided, In step (c), a suction force is applied to the mask in contact with the frame through a plurality of suction holes, so that the mask is tightly attached to the frame. The method for manufacturing a frame-integrated mask according to claim 1, wherein step (b) includes the following steps: (b1) forming a masking metal film on at least one surface of the conductive substrate by electroforming; (b2) Separating the mask metal film from the conductive substrate; (b3) bonding the mask metal film to the template on which one temporary bonding part is formed; and (b4) A mask pattern is formed on the mask metal film to manufacture a mask. The method for manufacturing a frame-integrated mask according to claim 1, wherein step (b) includes the following steps: (b1) providing a mask metal film, the mask metal being a sheet manufactured by rolling; (b2) Bonding the mask metal film to the template with a temporary bonding part formed on one side; (b3) A mask pattern is formed on the mask metal film to manufacture a mask. The method for manufacturing a frame-integrated mask according to claim 2 or 3, wherein step (c) is a step of loading the template on the frame and making the mask correspond to the mask unit area of the frame. The method for manufacturing a frame-integrated mask according to claim 1, wherein in step (c), a lower support body is arranged at a lower portion of the frame, the lower support body including an adsorption portion for generating suction pressure. The method for manufacturing a frame-integrated mask according to claim 5, wherein the lower support presses the opposite surface of the mask unit area for loading the mask. The method for manufacturing a frame-integrated mask according to claim 1, wherein the suction hole is formed on a portion that does not overlap with the welding portion of the mask. The method for manufacturing a frame-integrated mask according to claim 2, wherein the conductive substrate is a wafer, The process of heat-treating the mask metal film is further performed between step (b1) and step (b2). The method for manufacturing a frame-integrated mask according to claim 3, wherein between step (b2) and step (b3), a step of reducing the thickness of the mask metal film adhered on the template is also included, The thickness reduction of the mask metal film is performed by any one of CMP (Chemical Mechanical Polishing), chemical wet etching, and dry etching. The method for manufacturing a frame-integrated mask according to claim 2 or 3, wherein the temporary bonding part is based on a heat-separated adhesive or a bonding sheet, and is based on a UV-separating adhesive or a bonding sheet. The method for manufacturing a frame-integrated mask according to claim 2 or 3, wherein the step of forming a mask pattern on the mask metal film to manufacture the mask includes: (1) A patterned insulating part is formed on the mask metal film; (2) The mask metal film portion exposed between the insulating portions is etched to form a mask pattern; and (3) Remove the insulation. The method for manufacturing a frame-integrated mask according to claim 2 or 3, wherein the template includes wafer, glass, silicon oxide, heat-resistant glass, quartz, and alumina (Al2O3) ), any one of borosilicate glass and zirconia. The method for manufacturing a frame-integrated mask according to claim 4, wherein the laser irradiated from the upper part of the template passes through the laser penetrating hole and irradiates the welded portion of the mask. The method for manufacturing a frame-integrated mask as described in claim 4, further comprising the step of separating the mask and the template by heating, chemically treating, or applying ultrasonic waves to the temporary bonding part after step (d) . The method for manufacturing a frame-integrated mask according to claim 1, wherein the frame includes an edge frame portion and a mask unit sheet portion, The mask unit sheet portion includes an edge sheet portion; at least one first grid sheet portion extending in the first direction and connected at both ends to the edge sheet portion; and at least one second grid sheet portion, It extends along a second direction perpendicular to the first direction and crosses the first grid sheet portion, and both ends are connected to the edge sheet portion. The method for manufacturing a frame-integrated mask according to claim 1, wherein the mask and the frame are any one of constant invar, super invar, nickel, and nickel-cobalt. A frame used in a frame-integrated mask in which a plurality of masks are integrally formed with a frame for supporting the mask, wherein the frame includes: The edge frame portion, which includes a hollow area; The mask unit sheet portion, which has a plurality of mask unit regions along at least one of the first direction and the second direction perpendicular to the first direction, is connected to the edge frame portion, A plurality of suction holes are formed in the mask unit sheet portion. The frame according to claim 17, wherein a plurality of suction holes are formed in a portion at a predetermined distance from the corner of the frame where the mask unit area is provided, The suction hole is formed in a portion that does not overlap with the welding portion of the mask. The frame according to claim 17, wherein a lower part of the frame is further provided with an adsorption part for generating suction pressure. The frame according to claim 19, wherein at least one vacuum channel is formed on the lower support body, and the vacuum channel transmits the suction pressure generated on the external suction pressure generating device to the suction part.

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