Mask support template, manufacturing method thereof, and manufacturing method of frame-integrated mask

Abstract

The present invention relates to a mask support template, a manufacturing method thereof and a manufacturing method of a frame-integrated mask. The manufacturing method of the mask support template of the present invention is used to manufacture a template (50) that supports a mask (100) for forming OLED pixels and makes it correspond to a frame (200), and comprises the following steps: (a) providing a mask metal film (110); (b) bonding the mask metal film (110) to a template (50) having a temporary bonding portion (55) formed on a surface thereof; and (c) forming a mask pattern (P) on the mask metal film (110) to manufacture the mask (100).

Description

Technical Field

[0001] The present invention relates to a mask support template, a manufacturing method thereof, and a manufacturing method of a frame-integrated mask. More specifically, the present invention relates to a mask support template, a manufacturing method thereof, and a manufacturing method of a frame-integrated mask, which can stably support and move a mask without causing deformation, and can improve the adhesion between the mask and the frame when the mask and the frame are integrated, and can also accurately align the masks. Background Art

[0002] As a technology for forming pixels in the OLED (Organic Light Emitting Diode) manufacturing process, the FMM (Fine Metal Mask) method is mainly used, in which a metal mask (Shadow Mask) in the form of a thin film is closely attached to a substrate and organic matter is deposited at a desired position.

[0003] 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. A mask can have multiple units corresponding to one display. In addition, in order to manufacture large-area OLEDs, multiple masks can be fixed to the OLED pixel deposition frame, and in the process of fixing them to the frame, each mask is stretched to make it flat. Adjusting the stretching force to make the entire part of the mask flat is a very difficult task. In particular, in order to make all the units flat and align the mask pattern with a size of only a few μm to tens of μm, it is necessary to fine-tune the stretching force applied to each side of the mask and confirm the alignment status in real time, which is a highly demanding task.

[0004] Nevertheless, in the process of fixing multiple masks to a frame, there is still the problem of poor alignment between masks and between mask units. In addition, in the process of welding 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 the load; wrinkles and burrs generated in the welding part during the welding process cause the alignment of the mask unit to be misaligned.

[0005] In ultra-high-definition OLEDs, the existing QHD image quality is 500-600 PPI (pixel per inch), and the pixel size is about 30-50 μm, while 4K UHD and 8K UHD have higher resolutions of ~860 PPI and ~1600 PPI. In this way, considering the pixel size of ultra-high-definition OLEDs, the alignment error between units needs to be reduced to about a few μm. Exceeding this error will result in defective products, so the yield may be extremely low. Therefore, it is necessary to develop technologies that can prevent deformation such as sagging or twisting of the mask and make the alignment precise, as well as technologies for fixing the mask to the frame. Summary of the invention

[0006] Technical issues

[0007] Therefore, the present invention is proposed to solve the above-mentioned problems in the prior art and provides a mask support template and a method for manufacturing the mask support template in which the mask does not deform and can be stably supported and moved.

[0008] In addition, an object of the present invention is to provide a mask supporting template and a method for manufacturing the same which can improve the adhesion between the mask and the frame when the mask is bonded to the frame.

[0009] In addition, an object of the present invention is to provide a mask supporting template that can be repeatedly used after the mask is bonded to a frame and a method for manufacturing the same.

[0010] 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.

[0011] Another object of the present invention is to provide a method for manufacturing a frame-integrated mask that can prevent deformation such as sagging or twisting of the mask and can accurately align the mask.

[0012] Another object of the present invention is to provide a method for manufacturing a frame-integrated mask that can significantly shorten the manufacturing time and significantly improve the yield.

[0013] Technical Solution

[0014] The above-mentioned object of the present invention is achieved through a method for manufacturing a mask support template, wherein the mask support template is used to support a mask for forming OLED pixels and make it correspond to a frame, and the manufacturing method comprises the following steps: (a) providing a mask metal film; (b) bonding the mask metal film to a template having a temporary bonding portion formed on a surface; and (c) forming a mask pattern on the mask metal film to manufacture a mask.

[0015] A step of reducing the thickness of the mask metal film bonded to the template may be further included between step (b) and step (c).

[0016] When the mask metal film is formed by electroforming, step (a) may include the following steps: (a1) forming the mask metal film on at least one surface of the conductive single crystal substrate; and (a2) separating the mask metal film from the conductive single crystal substrate.

[0017] The temporary adhesive portion may be an adhesive or adhesive sheet removable by heating, or an adhesive or adhesive sheet removable by irradiating UV.

[0018] The step (c) may include the following steps: (c1) forming a patterned insulating portion on the mask metal film; (c2) etching portions of the mask metal film exposed between the insulating portions to form a mask pattern; and (c3) removing the insulating portion.

[0019] The temporary bonding portion may be formed on the entire surface of the template, and the mask metal film may be bonded to the entire surface of the temporary bonding portion.

[0020] The material of the template may include any one of wafer, glass, silica, heat-resistant glass, quartz, alumina (Al2O3), borosilicate glass, and zirconia.

[0021] In addition, the above-mentioned purpose of the present invention is achieved through a mask support template, which is used to support the mask for forming OLED pixels and make it correspond to the frame, including: a template; a temporary bonding portion formed on the template; and a mask, which is bonded to the template through the temporary bonding portion and forms a mask pattern.

[0022] The temporary adhesive portion may be an adhesive or adhesive sheet removable by heating, or an adhesive or adhesive sheet removable by irradiating UV.

[0023] A laser passing hole may be formed on a portion of the template corresponding to the welding portion of the mask.

[0024] The temporary bonding portion may be formed entirely on one surface of the template, and the mask metal film may be bonded to the entire surface of the temporary bonding portion.

[0025] The material of the template may include any one of wafer, glass, silica, heat-resistant glass, quartz, alumina (Al2O3), borosilicate glass, and zirconia.

[0026] The mask may include a mask unit in which a plurality of mask patterns are formed and a dummy portion around the mask unit.

[0027] In addition, the above-mentioned purpose of the present invention is achieved through a method for manufacturing a frame-integrated mask, wherein the frame-integrated mask is formed as a whole by at least one mask and a frame for supporting the mask, and the manufacturing method includes the following steps: (a) providing a mask metal film; (b) bonding the mask metal film to a template having a temporary bonding portion formed on a surface; (c) forming a mask pattern on the mask metal film to manufacture a mask; (d) providing a frame having at least one mask unit area; (e) loading the template on the frame so that the mask corresponds to the mask unit area of ​​the frame; and (f) irradiating a laser to the welding portion of the mask so that the mask is bonded to the frame.

[0028] Step (d) may include the following steps: (d1) providing an edge frame portion including a hollow area; (d2) connecting a planar mask unit sheet portion to the edge frame portion; and (d3) forming a plurality of mask unit areas on the mask unit sheet portion to manufacture a frame.

[0029] The step (d) may include the steps of: (d1) providing an edge frame portion including a hollow area; and (d2) connecting a mask unit sheet portion having a plurality of mask unit areas to the edge frame portion to manufacture a frame.

[0030] The temporary adhesive portion may be an adhesive or adhesive sheet removable by heating, or an adhesive or adhesive sheet removable by irradiating UV.

[0031] The laser irradiated from the upper portion of the template may pass through the laser passing hole and irradiate the welding portion of the mask.

[0032] After step (f), the method may further include heating, chemically treating, applying ultrasonic waves, or applying ultraviolet rays to the temporary adhesive portion to separate the mask from the template.

[0033] The mask and the frame may be made of any material of invar, super invar, nickel, or nickel-cobalt.

[0034] Beneficial Effects

[0035] According to the present invention having the above structure, there is an effect that the mask can be supported stably and moved without being deformed.

[0036] Furthermore, the present invention has an effect of being able to improve the adhesion between the mask and the frame when the mask is bonded to the frame.

[0037] Furthermore, the present invention has the effect that the mask can be repeatedly used after being bonded to the frame.

[0038] In addition, the present invention has the effect that the mask and the frame can form an integrated structure.

[0039] In addition, the present invention has an effect of preventing deformation such as sagging or twisting of the mask and enabling accurate alignment.

[0040] Furthermore, the present invention has the effect of being able to significantly shorten the production time and significantly improve the yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a schematic diagram of a conventional OLED pixel deposition mask.

[0042] Figure 2 is a schematic diagram of a conventional process for bonding a mask to a frame.

[0043] Figure 3 This is a schematic diagram of the alignment error between cells that occurs during the conventional mask stretching process.

[0044] Figure 4 1 is a front view and a side cross-sectional view of a frame-integrated mask according to an embodiment of the present invention.

[0045] Figure 5 2 is a front view and a side cross-sectional view of a frame according to an embodiment of the present invention.

[0046] Figure 6 is a schematic diagram of a frame manufacturing process according to an embodiment of the present invention.

[0047] Figure 7 is a schematic diagram of a frame manufacturing process according to another embodiment of the present invention.

[0048] Figure 8 This is a schematic diagram of a conventional mask used to form a high-resolution OLED.

[0049] Fig. 9 is a schematic diagram of a mask according to an embodiment of the present invention.

[0050] Fig.10 FIG. 4 is a schematic diagram of a process of manufacturing a mask metal film by rolling according to an embodiment of the present invention.

[0051] Fig.11 FIG. 4 is a schematic diagram of a process of manufacturing a mask metal film by electroforming according to another embodiment of the present invention.

[0052] Figure 12 to Figure 13 FIG. 1 is a schematic diagram of a process of bonding a mask metal film to a template to form a mask to manufacture a mask support template according to an embodiment of the present invention.

[0053] Fig.14 FIG. 1 is a schematic diagram of an enlarged cross section of a temporary adhesive portion according to an embodiment of the present invention.

[0054] Fig.15 is a schematic diagram of a process of loading a mask support template onto a frame according to an embodiment of the present invention.

[0055] Fig.16 1 is a schematic diagram of a state in which a template is loaded on a frame so that the mask corresponds to a unit area of ​​the frame according to an embodiment of the present invention.

[0056] Fig.17 FIG. 1 is a schematic diagram of a process of separating the mask from the template after bonding the mask to the frame according to an embodiment of the present invention.

[0057] Fig.18 FIG. 1 is a schematic diagram of a state where a mask is bonded to a frame according to an embodiment of the present invention.

[0058] Fig.19 FIG. 1 is a schematic diagram of an OLED pixel deposition apparatus using a frame-integrated mask according to an embodiment of the present invention.

[0059] Reference numerals:

[0060] 50: Template

[0061] 51: Laser through hole

[0062] 55: Temporary bonding section

[0063] 70: Lower support

[0064] 100: Mask

[0065] 110: Mask film

[0066] 200: Framework

[0067] 210: Edge frame

[0068] 220: Mask unit sheet portion

[0069] 221: Edge sheet section

[0070] 223: First grid sheet portion

[0071] 225: Second grid sheet portion

[0072] 1000: OLED pixel deposition device

[0073] C: Unit, mask unit

[0074] CM: Chemical treatment

[0075] CR: Mask cell region

[0076] DM: dummy part, mask dummy part

[0077] ET: Heating

[0078] L: Laser

[0079] R: Hollow area of ​​the edge frame

[0080] P: Mask pattern

[0081] US: Ultrasonic waves

[0082] UV: Apply ultraviolet light

[0083] W: Welding

[0084] WB: Weld Bead DETAILED DESCRIPTION

[0085] The detailed description of the present invention described below will refer to the accompanying drawings, which illustrate specific embodiments that can implement the present invention as examples. These embodiments are described in full detail so that those with ordinary knowledge in the art can implement the present invention. It should be understood that the various embodiments of the present invention, although different from each other, are not mutually exclusive. For example, the specific shapes, structures and characteristics recorded here 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, the position or configuration of individual constituent elements in each disclosed embodiment can be changed without departing from the spirit and scope of the present invention. Therefore, the detailed description described below should not be regarded as having a limiting meaning, and the scope of the present invention is limited only by the scope of the attached patent application and all scopes equivalent thereto. Similar symbols in the drawings represent the same or similar functions from many aspects, and for convenience, length, area, thickness and shape thereof can be exaggerated.

[0086] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that a person having ordinary knowledge in the technical field can easily implement the present invention.

[0087] Figure 1 FIG. 1 is a schematic diagram of a conventional mask 10 for OLED pixel deposition.

[0088] Reference Figure 1 The existing mask 10 can be manufactured in a stick-type or a plate-type. Figure 1 The mask 10 shown in (a) is used as a strip mask, and both sides of the strip can be welded and fixed to the OLED pixel deposition frame and used. Figure 1 The mask 100 shown in (b) can be used as a plate mask in a large-area pixel formation process.

[0089] The body (Body, or mask film 11) of the mask 10 has a plurality of display cells C. One cell C corresponds to one display of a smartphone, etc. A pixel pattern P is formed in the cell C so as to correspond to each pixel of the display. When the cell 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 are formed as a set to constitute one cell C, and a plurality of cells C can be formed on the mask 10.

[0090] Figure 2 1 is a schematic diagram of a conventional process of bonding the mask 10 to the frame 20 . Figure 3 FIG. 1 is a schematic diagram showing the alignment error between cells that occurs during the conventional stretching process of the F1-F2 mask 10. Figure 1 The stripe mask 10 having six cells C (C1-C6) in (a) is taken as an example for description.

[0091] Reference Figure 2 (a), first, the strip mask 10 should be unfolded flatly. A tensile force F1-F2 is 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 loaded on a frame 20 in a square frame shape. The cells C1-C6 of the strip mask 10 will be located in the blank area inside the frame 20. The size of the frame 20 can be sufficient to allow the cells C1-C6 of one strip mask 10 to be located in the blank area inside the frame, and can also be sufficient to allow the cells C1-C6 of multiple strip masks 10 to be located in the blank area inside the frame.

[0092] Reference Figure 2 (b), after fine-tuning the tensile forces F1-F2 applied to the respective sides of the strip mask 10 while performing alignment, a portion of the side surface of the strip mask 10 is welded, and the strip mask 10 and the frame 20 are connected. Figure 2 (c) shows a side section of the stripe mask 10 and the frame connected to each other.

[0093] Reference Figure 3 , despite fine-tuning the stretching force F1-F2 applied to each side of the strip mask 10, the problem of poor alignment between the mask units C1-C3 still occurs. For example, the distances D1-D1", D2-D2" between the patterns P of the units 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 of (as an example, 6) units C1-C6 and has a very thin thickness of tens of μm, it is easy to sag or twist due to the load. In addition, it is a very difficult task to adjust the stretching force F1-F2 so that all the units C1-C6 become flat while confirming the alignment status between the units C1-C6 in real time through a microscope.

[0094] Therefore, a slight error in the stretching force F1-F2 may cause an error in the stretching or expansion degree of each unit C1-C3 of the strip mask 10, thereby resulting in different distances D1-D1", D2-D2" between the mask patterns P. Although it is very difficult to perfectly align so that the error is 0, in order to avoid the mask pattern P with a size of several μm to tens of μm from having a bad influence on the pixel process of the ultra-high-definition OLED, the alignment error is preferably not greater than 3 μm. The alignment error between such adjacent units is called pixel position accuracy (PPA).

[0095] In addition, it is a very difficult task to connect approximately 6 to 20 strip masks 10 to one frame 20 while accurately aligning the multiple strip masks 10 and the multiple units C1 to C6 of the strip masks 10, and this only increases the process time based on alignment, which becomes an important reason for reducing productivity.

[0096] On the other hand, after the strip mask 10 is connected and fixed to the frame 20, the tensile force F1-F2 applied to the strip mask 10 can act on the frame 20 in reverse. That is, after the strip mask 10 is connected to the frame 20 by the tensile force F1-F2 being stretched, tension can be applied to the frame 20. Generally, when the tension is not large, it will not have a great impact on the frame 20, but when the size of the frame 20 is miniaturized and the strength is reduced, this tension will cause the frame 20 to deform slightly. In this way, the alignment state between the plurality of cells C1-C6 may be destroyed.

[0097] In view of this, the present invention proposes a frame 200 and a frame-integrated mask that can form an integrated structure between the mask 100 and the frame 200. Not only can the mask 100 formed integrally with the frame 200 be prevented from being deformed such as sagging or twisting, but it can also 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, so after the mask 100 is connected to the frame 200, no tension that causes deformation is applied to the frame 200. In addition, the manufacturing time of integrally connecting the mask 100 to the frame 200 can be significantly shortened, and the yield can be significantly improved.

[0098] Figure 4 is a front view of a frame-integrated mask according to an embodiment of the present invention ( Figure 4 (a)) and side cross-sectional view ( Figure 4 (b)), Figure 5 is a front view of a frame according to an embodiment of the present invention ( Figure 5 (a)) and side cross-sectional view ( Figure 5 (b)).

[0099] Reference Figure 4 as well as Figure 5 , the frame-integrated mask may include a plurality of masks 100 and a frame 200. In other words, the plurality of masks 100 are bonded to the frame 200. Below, for the sake of convenience, although a quadrangular mask 100 is used as an example, the mask 100 may be a strip-shaped mask with protrusions for clamping on both sides before being bonded to the frame 200, and the protrusions may be removed after being bonded to the frame 200.

[0100] A plurality of mask patterns P are formed on each mask 100, and one mask 100 may be formed with one cell C. One mask cell C may correspond to one display of a smartphone or the like.

[0101] The mask 100 may have a thermal expansion coefficient of about 1.0×10 -6 / ℃ of Invar alloy or about 1.0×10 -7 / ℃ super invar material. Since the thermal expansion coefficient of the mask 100 made of this material is very low, the pattern shape of the mask is less likely to be deformed by thermal energy. In the manufacture of high-resolution OLEDs, it can be used as an FMM (Fine Metal Mask) or a shadow mask. In addition, considering the recent development of technology for implementing pixel deposition processes within a range of small temperature changes, the mask 100 can also be made of materials such as nickel (Ni) and nickel-cobalt (Ni-Co) with a slightly larger thermal expansion coefficient. The mask 100 can use a metal sheet generated by a rolling process or electroforming. The following is a description of the process. Fig. 9 and Fig.10 Specific instructions.

[0102] The frame 200 is formed in a form capable of bonding a plurality of masks 100. The frame 200 may include a plurality of corners formed along a first direction (e.g., lateral direction) and a second direction (e.g., vertical direction) including the outermost edge. Such a plurality of corners may divide the region for bonding the mask 100 on the frame 200.

[0103] The frame 200 may include an edge frame portion 210 that is approximately quadrangular or square. The inside of the edge frame portion 210 may be hollow. That is, the edge frame portion 210 may include a hollow region R. The frame 200 may be formed of metal materials such as Invar, Super Invar, aluminum, and titanium. Considering thermal deformation, the frame 200 is preferably formed of materials such as Invar, Super Invar, nickel, and nickel-cobalt that have the same thermal expansion coefficient as the mask. These materials may be applied to the edge frame portion 210 and the mask unit sheet portion 220 that are components of the frame 200.

[0104] In addition, the frame 200 has a plurality of mask unit regions CR, and may include a 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 may be formed by rolling, or by other film forming processes such as electroforming. 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, etc. Alternatively, the mask unit sheet portion 220 may be connected to the edge frame portion 210 by laser scribing, etching, etc. after connecting a planar sheet to the edge frame portion 210. This specification mainly describes the case where a plurality of mask unit regions CR are first formed on the mask unit sheet portion 220 and then connected to the edge frame portion 210.

[0105] The mask unit sheet portion 220 may include at least one of an edge sheet portion 221, a first grid sheet portion 223, and a second grid sheet portion 225. The edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 are parts divided on the same sheet and are integrated with each other.

[0106] The edge sheet portion 221 may be substantially connected to the edge frame portion 210. Therefore, the edge sheet portion 221 may have a substantially quadrangular shape or a square frame shape corresponding to the edge frame portion 210.

[0107] 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, 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.

[0108] In addition, the second grid sheet portion 225 may be formed to extend along the second direction (vertical direction), and the second grid sheet portion 225 may be formed in a straight line, 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 vertically. 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 spacing.

[0109] On the other hand, depending on the size of the mask unit C, the intervals between the first grid sheet portions 223 and the intervals between the second grid sheet portions 225 may be the same or different.

[0110] Although the first grid sheet portion 223 and the second grid sheet portion 225 have a thin film-like thickness, the cross-sectional shape perpendicular to the length direction can be a quadrilateral shape such as a rectangle, a parallelogram, a triangle, etc., and the sides and corners can be rounded. The cross-sectional shape can be adjusted during laser scribing, etching, etc.

[0111] The thickness of the edge frame portion 210 may be greater than the thickness of the mask unit sheet portion 220. Since the edge frame portion 210 is responsible for the overall rigidity of the frame 200, it may be formed to have a thickness of several mm to several cm.

[0112] As for the mask unit sheet portion 220, it is actually more difficult to manufacture a thick sheet. If it is too thick, it is possible that the organic source 600 (refer to Fig.19 ) blocks the path through the mask 100. On the contrary, if it is too thin, it may be difficult to ensure sufficient rigidity to support the mask 100. Therefore, the mask unit sheet portion 220 is preferably thinner than the edge frame portion 210, but thicker than the mask 100. The thickness of the mask unit sheet portion 220 can 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 can be about 1 to 5 mm.

[0113] 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, the first grid sheet portion 223, and the second grid sheet portion 225. From another perspective, the mask unit region CR may refer to a blank region in the hollow region R of the edge frame portion 210 except for the regions occupied by the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225.

[0114] As the cell C of the mask 100 corresponds to the mask cell region CR, it can be used as a channel for depositing pixels of the OLED through the mask pattern P. As described above, one mask cell C corresponds to one display of a smartphone or the like. A mask pattern P for constituting one cell C may be formed in one mask 100. Alternatively, one mask 100 has a plurality of cells C and each cell C corresponds to each mask cell region CR of the frame 200, but in order to accurately align the mask 100, it is necessary to avoid using a large area of ​​the mask 100, and the mask 100 preferably has a small area of ​​one cell C. Alternatively, one mask 100 having a plurality of cells C may also correspond to one mask cell region CR of the frame 200. At this time, in order to accurately align, it may be considered to correspond to a mask 100 having a small number of cells C of about 2-3.

[0115] The mask 200 has a plurality of mask unit regions CR, and each mask 100 can be bonded so that each mask unit C corresponds to each mask unit region CR. Each mask 100 may include a mask unit C formed with a plurality of mask patterns P and a dummy portion (equivalent to the portion of the mask film 110 other than the unit C) around the mask unit C. The dummy portion may include only the mask film 110, or may include a mask film 110 formed with a predetermined dummy portion pattern having a similar form to the mask pattern P. The mask unit C corresponds to the mask unit region CR of the frame 200, and a portion or all of the dummy portion may be bonded to the frame 200 (mask unit sheet portion 220). Thus, the mask 100 and the frame 200 may form an integrated structure.

[0116] On the other hand, according to another embodiment, the frame is not manufactured by bonding the mask unit sheet portion 220 to the edge frame portion 210, but a frame in which a grid frame (equivalent to the grid sheet portions 223 and 225) integrated with the edge frame portion 210 is directly formed in the hollow region R of the edge frame portion 210. This form of frame 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.

[0117] Next, a manufacturing process of the frame-integrated mask will be described.

[0118] First, it can provide Figure 4 and Figure 5 The frame 200 described in. Figure 6 FIG. 2 is a schematic diagram of a manufacturing process of the frame 200 according to an embodiment of the present invention.

[0119] Reference Figure 6 (a), an edge frame portion 210 is provided. The edge frame portion 210 may be in a square frame shape including a hollow area R.

[0120] Secondly, refer to Figure 6 (b) to manufacture the mask unit sheet portion 220. The mask unit sheet portion 220 is manufactured by rolling, electroforming or other film forming processes to manufacture a planar sheet, and then the mask unit region CR portion is removed by laser scribing, etching, etc. In this specification, the formation of 6×5 mask unit regions CR (CR11-CR56) is used as an example for explanation. There may be 5 first grid sheet portions 223 and 4 second grid sheet portions 225.

[0121] Then, the mask unit sheet portion 220 can be aligned with the edge frame portion 210. In the alignment process, the edge sheet portion 221 can be aligned with the edge frame portion 210 in a state where all sides of the mask unit sheet portion 220 are stretched F1-F4 so that the mask unit sheet portion 220 is flat and stretched. Figure 6 In the example of (b), the mask unit sheet portion 220 is clamped and stretched at points 1 to 3. On the other hand, the mask unit sheet portion 220 may be stretched along a part of the side instead of all the side portions.

[0122] Then, when the mask unit sheet portion 220 is aligned with the edge frame portion 210, the edge sheet portion 221 of the mask unit sheet portion 220 may be bonded by welding. Preferably, all sides are welded so that the mask unit sheet portion 220 is firmly bonded to the edge frame portion 210. The welding should be performed as close to the corner side of the frame portion 210 as possible, so as to minimize the warping space between the edge frame portion 210 and the mask unit sheet portion 220 and improve the bonding. The welding portion may be generated in a line or spot shape, has the same material as the mask unit sheet portion 220, and may become a medium for connecting the edge frame portion 210 and the mask unit sheet portion 220 into one body.

[0123] Figure 7 is a schematic diagram of a frame manufacturing process according to another embodiment of the present invention. Figure 6 In the embodiment, the mask unit sheet portion 220 having the mask unit region CR is first manufactured, and then bonded to the edge frame portion 210. Figure 7 In the embodiment, the planar sheet is bonded to the edge frame portion 210 and then the mask unit region CR portion is formed.

[0124] First, if Figure 6 As shown in (a), an edge frame portion 210 including a hollow area R is provided.

[0125] Then, refer to Figure 7(a) The planar sheet (planar mask unit sheet portion 220') can be matched to the edge frame portion 210. The mask unit sheet portion 220' is in a planar state where the mask unit region CR has not yet been formed. In the matching process, the mask unit sheet portion 220' can be matched to the edge frame portion 210 while stretching all sides of the mask unit sheet portion F1-F4 and making the mask unit sheet portion 220' flat and stretched. On one side, multiple points (as Figure 7 In the example of (a), the unit sheet portion 220' is clamped and stretched at points 1 to 3. On the other hand, the F1 and F2 mask unit sheet portions 220' may be stretched along a part of the side portions instead of all the side portions.

[0126] Then, after the mask unit sheet portion 220' corresponds to the edge frame portion 210, the edge portion of the mask unit sheet portion 220' can be bonded by welding. Preferably, all sides are welded so that the mask unit sheet portion 220' is firmly bonded to the edge frame portion 220. The welding should be performed as close as possible to the corner side of the edge frame portion 210, so as to minimize the warping space between the edge frame portion 210 and the mask unit sheet portion 220' and improve the adhesion. The welding portion can be generated in a line or point shape, has the same material as the mask unit sheet portion 220', and can become a medium for connecting the edge frame portion 210 and the mask unit sheet portion 220' into one.

[0127] Then, refer to Figure 7 (b) A mask unit region CR is formed on a planar sheet (a 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, the formation of 6×5 mask unit regions CR (CR11-CR56) is used as an example. After the mask unit region CR is formed, a mask unit sheet portion 220 can be formed, wherein the portion welded W to the edge frame portion 210 becomes an edge sheet portion 221, and the mask unit sheet portion 220 has 5 first grid sheet portions 223 and 4 second grid sheet portions 225.

[0128] Figure 8 This is a schematic diagram of a conventional mask used to form a high-resolution OLED.

[0129] In order to realize high-resolution OLED, the size of the pattern gradually becomes smaller, and the thickness of the mask metal film used must also be thinner. Figure 8As shown in (a), to achieve high-resolution OLED pixels 6, it is necessary to reduce the pixel spacing and pixel size in the mask 10' (PD->PD'). In addition, in order to prevent the shadow effect from causing uneven deposition of the OLED pixels 6, it is necessary to form the pattern of the mask 10' at an angle 14. However, in the process of obliquely forming the pattern 14 in a thicker mask 10' having a thickness T1 of about 30-50μm, it is difficult to perform patterning 13 that matches the fine pixel spacing PD' and pixel size, which becomes a factor that reduces the yield in the processing process. In other words, in order to have a fine pixel spacing PD' and obliquely form the pattern 14, a thinner mask 10' should be used.

[0130] In particular, in order to achieve UHD-level high resolution, such as Figure 8 As shown in (b), fine patterning can only be performed by using a thin mask 10' having a thickness T2 of 20 μm or less. In order to achieve ultra-high resolution above UHD, it is conceivable to use a thinner mask 10' having a thickness T2 of 10 μm.

[0131] Fig. 9 is a schematic diagram of a mask 100 according to an embodiment of the present invention.

[0132] 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. As described above, the mask 100 may be manufactured using a metal sheet produced by a rolling process, electroforming, etc., and as described above, one unit 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 unit C, and may include only the mask film 110, or include the mask film 110 formed with a predetermined dummy portion pattern similar to the mask pattern P. The dummy portion DM corresponds to the edge of the mask 100, and a portion or all of the dummy portion DM may be bonded to the frame 200 (mask unit sheet portion 220).

[0133] 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-CR56), it may also have a plurality of masks 100 including mask units C (C11-C56) corresponding to each mask unit region CR (CR11-CR56).

[0134] Since one surface 101 of the mask 100 is in contact with and bonded to one surface of the frame 200, it is preferably a flat surface. One surface 101 can be flattened and mirror-finished by a flattening process described below. Another surface 102 of the mask 100 can be opposite to one surface of the template 50 described below.

[0135] Next, a series of processes for manufacturing a mask metal film 110 ′, supporting it on a template 50 to manufacture a mask 100 , loading the template 50 supporting the mask 100 on a frame 200 , and bonding the mask to the frame 200 to manufacture a frame-integrated mask will be described.

[0136] Fig.10 FIG. 4 is a schematic diagram of a process of manufacturing a mask metal film by rolling according to an embodiment of the present invention. Fig.11 FIG. 4 is a schematic diagram of a process of manufacturing a mask metal film by electroforming according to another embodiment of the present invention.

[0137] First, a mask metal film 110 may be prepared. As an embodiment, the mask metal film 110 may be prepared by rolling.

[0138] Reference Fig.10 (a), the metal sheet produced by the rolling process can be used as the mask metal film 110'. The metal sheet produced by the rolling process can have a thickness of tens to hundreds of μm according to the manufacturing process. Figure 8 As described in the , in order to obtain UHD-level high resolution, only a thinner mask metal film 110 with a thickness of 20 μm or less can be used for fine patterning, and in order to obtain ultra-high resolution above UHD, a thinner mask metal film 110 with a thickness of about 10 μm is required. However, the thickness of the mask metal film 110' generated by the rolling process is about 25-500 μm, so it is necessary to further reduce the thickness.

[0139] Therefore, a process of flattening PS on one surface of the mask metal film 110' can be further performed. Herein, the flattening PS refers to the process of mirroring one surface (upper surface) of the mask metal film 110' while thinning the thickness by partially removing the upper part of the mask metal film 110'. The flattening PS can be performed using a CMP (Chemical Mechanical Polishing) method, and any known CMP method can be used without restriction. In addition, the thickness of the mask metal film 110' can be thinned using a chemical wet etching method or a dry etching method. In addition, there is no restriction on the flattening process as long as it can reduce the thickness of the mask metal film 110'.

[0140] In the process of performing the planarization PS, as an example, the surface roughness Ra of the upper surface of the mask metal film 110' is controlled during the CMP process. Preferably, mirroring is performed to further reduce the surface roughness. Alternatively, as another example, the planarization PS can also be performed by a chemical wet etching or dry etching process, and then an additional polishing process such as CMP is additionally performed to reduce the surface roughness Ra.

[0141] Thus, the mask metal film 110 ′ can be manufactured to have a thickness of about 50 μm or less. Therefore, the thickness of the mask metal film 110 is preferably formed to be about 2 μm to 50 μm, and more preferably, the thickness can be about 5 μm to 20 μm. However, it is not necessarily limited thereto.

[0142] Reference Fig.10 (b), and Fig.10 The mask metal film 110 can be manufactured by reducing the thickness of the mask metal film 110' manufactured by the rolling process, as in (a). However, the mask metal film 110' is bonded to the template 50 described later with a temporary bonding portion 55 provided in the middle, and the planarization PS process is performed in this state, so that the thickness can be reduced.

[0143] As another embodiment, the mask metal film 110 may be prepared by electroforming.

[0144] Reference Fig.11 (a) , prepare a conductive substrate 21. In order to perform electroforming, the substrate 21 of the master plate can be a conductive material. The master plate can be used as a cathode electrode in electroforming.

[0145] As a conductive material, metal oxides are generated on the metal surface, impurities flow in during the metal manufacturing process, inclusions or grain boundaries exist on the polysilicon substrate, and the conductive polymer substrate is likely to contain impurities, and is weak in strength and acid resistance. The elements such as metal oxides, impurities, inclusions, and grain boundaries that prevent the uniform formation of an electric field on the surface of the motherboard (or cathode body) are referred to as "defects". Due to such defects, a uniform electric field cannot be applied to the cathode body of the above-mentioned material, resulting in a part of the plated film 110 (mask metal film 110) being formed unevenly.

[0146] In realizing ultra-high-quality pixels above the UHD level, the unevenness of the coating and the coating pattern (mask pattern P) will have a good or bad effect on the pixel formation. For example, the current QHD image quality is 500-600PPI, and the pixel size reaches about 30-50μm. The 4K UHD and 8K UHD high-quality images have a higher resolution of ~860PPI, ~1600PPI, etc. than the former. The microdisplay directly applied to the VR machine or the microdisplay inserted into the VR machine aims at ultra-high image quality of about 2000PPI or above, and the pixel size is about 5-10μm. The pattern width of the FMM and shadow mask used therein can be formed to be several μm to tens of μm, preferably less than 30μm, so even defects of several μm in size occupy a large proportion in the mask pattern. In addition, in order to remove the defects of the above-mentioned materials in the cathode body, an additional process for removing metal oxides, impurities, etc. can be carried out, and other defects such as etching of the cathode body material may be additionally generated in the process.

[0147] Therefore, the present invention can use a mother plate (or cathode body) made of a single crystal material. A single crystal silicon material is particularly preferred. The mother plate made of a single crystal silicon material can be subjected to 10 19 / cm 3 The above high concentration doping is performed to make the motherboard conductive. The doping can be performed on the entire motherboard or only on the surface part of the motherboard.

[0148] On the other hand, single crystal materials can use metals such as Ti, Cu, and Ag; semiconductors such as GaN, SiC, GaAs, GaP, AlN, InN, InP, and Ge; carbon materials such as graphite and graphene; single crystal ceramics for superconductors such as perovskite structures including CH3NH3PbCl3, CH3NH3PbBr3, CH3NH3PbI3, and SrTiO3; and single crystal super heat-resistant alloys for aircraft parts. Metals and carbon materials are basically conductive materials. For semiconductor materials, in order to have conductivity, 10 19 / cm 3 Other materials can be made conductive by performing doping or forming oxygen vacancies. Doping can be performed on the entire motherboard or only on the surface of the motherboard.

[0149] Since the single crystal material has no defects, it has the advantage of forming a uniform electric field on the entire surface during electroforming, thereby generating a uniform coating film 110. The frame-integrated mask 100, 200 manufactured by the uniform coating film can further improve the image quality of the OLED pixel. In addition, since there is no need to perform an additional process to remove or eliminate defects, it has the advantage of reducing process costs and improving productivity.

[0150] Refer again Fig.10 (a), the conductive substrate 21 is then used as a motherboard (cathode body), and the anode body (not shown) is arranged at a distance, so that the plated film 110 (or the mask metal film 110) can be formed on the conductive substrate 21 by electroforming. The plated film 110 can be formed on the exposed upper surface and side surface of the conductive substrate 21, and the conductive substrate 21 is arranged opposite to the anode body and an electric field can be applied. Not only the side surface of the conductive substrate 21, but also a part of the lower surface of the conductive substrate 21 can be formed with the plated film 110.

[0151] Then, the edge of the D coating film 110 is cut by laser or a photoresist layer is formed on the upper part of the coating film 110 and only the exposed portion of the D coating film 110 is etched and removed. Fig.10 As shown in (b) , the plated film 110 can be separated from the conductive substrate 21 .

[0152] On the other hand, before separating the plated film 110 from the conductive substrate 21, a heat treatment H may be performed. The present invention is characterized in that a heat treatment H is performed before separating the plated film 110 from the conductive substrate 21 (or motherboard, cathode body) in order to reduce the thermal expansion coefficient of the mask 100 and prevent the mask 100 and the mask pattern P from being deformed by heat. The heat treatment may be performed at a temperature of 300°C to 800°C.

[0153] Generally, the thermal expansion coefficient of the Invar alloy sheet produced by electroforming is higher than that of the Invar alloy sheet produced by rolling. Therefore, the thermal expansion coefficient can be reduced by heat-treating the Invar alloy sheet, but the Invar alloy sheet may peel off, deform, etc. during the heat treatment. This is because the phenomenon occurs when only the Invar alloy sheet is heat-treated or the Invar alloy sheet temporarily bonded only to the upper surface of the conductive substrate 21 is heat-treated. However, the present invention forms the plating film 110 not only on the upper surface of the conductive substrate 21 but also on the side and part of the lower surface, so that even if the heat treatment H is performed, peeling, deformation, etc. will not occur. In other words, since the heat treatment is performed in a state where the conductive substrate 21 and the plating film 110 are tightly bonded, the present invention has the advantages of being able to prevent peeling, deformation, etc. caused by the heat treatment and being able to stably perform the heat treatment.

[0154] The thickness of the mask metal film 110 generated by the electroforming process is thinner than that generated by the rolling process. Therefore, the flattening PS process for thinning the thickness can be omitted, but the etching characteristics will be different depending on the composition, crystal structure / microstructure of the surface layer of the plated mask metal film 110', so it is necessary to control the surface characteristics and thickness through the flattening PS process.

[0155] Figure 12 to Figure 13FIG. 1 is a schematic diagram of a process of bonding a mask metal film 110 to a template 50 and forming a mask 100 to manufacture a mask support template according to an embodiment of the present invention.

[0156] Reference Fig.12 (a) of the present invention may provide a template 50. The template 50 is a medium that moves the state in which the mask 100 is attached and supported on one surface of the template 50. One surface of the template 50 is preferably in a flat shape so that the flat mask 100 can be supported and moved. The center portion 50a corresponds to the mask unit 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 template 50 may be in a large flat plate shape having a size larger than the mask metal film 110 so that the mask metal film 110 is supported as a whole.

[0157] In order to facilitate visual observation during the process of aligning and bonding the mask 100 to the frame 200, the template 50 is preferably made of a transparent material. Moreover, if it is a transparent material, the laser can also pass through. As transparent materials, materials such as glass, silica, heat-resistant glass, quartz, aluminum oxide (Al2O3), borosilicate glass, and zirconium oxide can be used. As an example, the template 50 can be made of borosilicate glass, which has excellent heat resistance, chemical durability, mechanical strength, transparency, etc. 33 materials. Moreover, The thermal expansion coefficient of 33 is about 3.3, which is not much different from the thermal expansion coefficient of the Invar alloy mask metal film 110, and has the advantage of being easy to control the mask metal film 110.

[0158] On the other hand, in order to prevent air gaps from being generated at the interface between the template 50 and the mask metal film 110 (or the mask 100), a surface of the template 50 in contact with the mask metal film 110 may be a mirror surface. Based on this, the surface roughness Ra of one surface of the template 50 may be less than 100 nm. In order to achieve a template 50 with a surface roughness Ra of less than 100 nm, a wafer may be used for the template 50. The surface roughness Ra of a wafer is about 10 nm, and there are many products on the market, and the surface treatment process is widely known, so it can be used as a template 50. The surface roughness Ra of the template 50 is at the nm level, so there is no air gap AG or the air gap AG is almost non-existent, and welding beads WB are easily generated based on laser welding, so the alignment error of the mask pattern P is not affected.

[0159] Laser passing holes 51 may be formed on the template 50 so that the laser L irradiated from the upper part of the template 50 reaches the welding part (the area where welding is performed) of the mask 100. The laser passing holes 51 may be formed on the template 50 corresponding to the position and number of the welding parts. The welding parts may be arranged in plurality at the edge or the dummy part DM of the mask 100 at predetermined intervals, so the laser passing holes 51 may also be formed in plurality corresponding thereto and at predetermined intervals. As an example, since the welding parts are arranged in plurality at predetermined intervals at the dummy part DM on both sides (left / right) of the mask 100, the laser passing holes 51 may also be formed in plurality at predetermined intervals on both sides (left / right) of the template 50.

[0160] The laser through holes 51 do not necessarily correspond to the positions and numbers of the welding parts. For example, it is also possible to irradiate the laser L only to a part of the laser through holes 51 and perform welding. In addition, a part of the laser through holes 51 that does not correspond to the welding part can also be used as an alignment mark when aligning the mask 100 and the template 50. If the material of the template 50 is transparent to the laser L light, the laser through holes 51 may not be formed.

[0161] A temporary adhesive portion 55 may be formed on one surface of the template 50. The temporary adhesive portion 55 may be formed on the entire surface of one surface of the template 50. The mask 100 (mask metal film 110) may be bonded to the entire surface of the temporary adhesive portion 55. Before the mask 100 is bonded to the frame 200, the temporary adhesive portion 55 allows the mask 100 (or the mask metal film 110) to be temporarily bonded to one surface of the template 50 and supported on the template 50.

[0162] The temporary adhesive portion 55 may use an adhesive or adhesive sheet that is removable by heating; or an adhesive or adhesive sheet that is removable by UV irradiation.

[0163] As an example, the temporary adhesive portion 55 may use liquid wax. The liquid wax may be the same wax as that used in the semiconductor wafer polishing step, etc., and its type is not particularly limited. The liquid wax mainly includes substances such as acrylic acid, vinyl acetate, nylon, and various polymers and solvents as resin components for controlling the adhesion, impact resistance, etc. related to the retention force. As an example, the temporary adhesive portion 55 may use acrylonitrile-butadiene rubber (ABR) as a resin component and SKYLIQUIDABR-4016 containing n-propyl alcohol as a solvent component. The liquid wax may be formed on the temporary adhesive portion 55 by spin coating.

[0164] The temporary adhesive part 55 as liquid wax has a lower viscosity at a temperature higher than 85° C. to 100° C., and becomes more viscous at a temperature lower than 85° C., and a part of it becomes hard like a solid, so that the mask metal film 110 ′ can be fixedly bonded to the template 50 .

[0165] Then, refer to Fig.12 (b) The mask metal film 110' can be bonded to the template 50. After the liquid wax is heated to 85°C or more and the mask metal film 110' is brought into contact with the template 50, the mask metal film 110' and the template 50 are passed between rollers and bonded.

[0166] According to one embodiment, the template 50 is baked at a temperature of about 120° C. for 60 seconds to vaporize the solvent of the temporary adhesive portion 55, and the lamination process of the mask metal film is directly performed. The lamination can be performed by loading the mask metal film 110' on the template 50 having the temporary adhesive portion 55 formed on one surface 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 contacted on the template 50 through the temporary adhesive portion 55.

[0167] Fig.14 : is a schematic diagram of an enlarged cross-section of a temporary adhesive portion 55 according to an embodiment of the present invention. As another example, the temporary adhesive portion 55 may use a thermal release tape. The thermal release tape is a core film 56 with a PET film or the like arranged in the middle, and thermally removable adhesive layers (thermal release adhesive) 57a, 57b are arranged on both sides of the core film 56, and peeling films / release films 58a, 58b may be arranged on the periphery of the adhesive layers 57a, 57b. Among them, the peeling temperatures of the adhesive layers 57a, 57b arranged on both sides of the core film 56 may be different from each other.

[0168] According to one embodiment, when the peeling films / release films 58a and 58b are removed, the lower surface (second adhesive layer 57b) of the thermal peeling tape can be bonded to the template 50, and the upper surface (first adhesive layer 57a) of the thermal peeling tape can be bonded to the mask metal film 110'. The peeling temperatures of the first adhesive layer 57a and the second adhesive layer 57b are different from each other, so in the following description, Fig.17 In the embodiment, when the template 50 is separated from the mask 100 , the mask 100 can be separated from the template 50 and the temporary adhesive portion 55 by heating the first adhesive layer 57 a .

[0169] Next, refer to Fig.12 (b), a surface of the mask metal film 110' may be planarized PS. As described above, Fig.10The thickness of the mask metal film 110' made by the rolling process can be thinned by the planarization PS process (110'->110). Moreover, the mask metal film 110 made by the electroforming process can also be subjected to the planarization PS process to control its surface characteristics and thickness.

[0170] Therefore, if Fig.12 As shown in (c), as the thickness of the mask metal film 110 ′ decreases ( 110 ′->110 ), the thickness of the mask metal film 110 may become about 5 μm to 20 μm.

[0171] Then, refer to Fig.13 (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.

[0172] Next, the mask metal film 110 may be etched. Dry etching, wet etching, or the like may be used without particular limitation, and as a result, the mask metal film 110 exposed at the empty positions 26 between the insulating portions 25 is etched. The etched portions of the mask metal film 110 constitute the mask pattern P, and thus the mask 100 having a plurality of mask patterns P formed thereon may be manufactured.

[0173] Then, refer to Fig.13 (e) The manufacturing of the template 50 supporting the mask 100 can be completed by removing the insulating portion 25 .

[0174] Since the frame 200 has a plurality of mask cell regions CR (CR11 to CR56), the frame 200 may include a plurality of masks 100 including mask cells C (C11 to C56) corresponding to the respective mask cell regions CR (CR11 to CR56). In addition, the frame 200 may include a plurality of templates 50 that support the plurality of masks 100, respectively.

[0175] Fig.15 It is a schematic diagram of a process of loading a mask support template onto a frame according to an embodiment of the present invention.

[0176] Reference Fig.15 The template 50 can be transferred by the vacuum suction cup 90. The vacuum suction cup 90 sucks the opposite side of the template 50 to which the mask 100 is bonded and transfers it. The vacuum suction cup 90 can be connected to a moving means (not shown) that moves in the x, y, z, and θ axes. In addition, the vacuum suction cup 90 can suck the template 50 and connect to a flipping means (not shown) that can flip it. Fig.15 As shown in (b), even when the vacuum chuck 90 adsorbs the template 50 and turns it over before transferring it to the frame 200, the adhesion state and alignment state of the mask 100 are not affected.

[0177] Fig.16 1 is a schematic diagram of a state in which a template is loaded on a frame so that the mask corresponds to a mask unit area of ​​the frame according to an embodiment of the present invention. Fig.16 Although an example of matching / bonding one mask 100 to the mask unit region CR is shown, a process of matching a plurality of masks 100 to the respective mask unit regions CR simultaneously and bonding the masks 100 to the frame 200 may be performed. In this case, a plurality of templates 50 for supporting the plurality of masks 100 may be provided.

[0178] Then, refer to Fig.16 , the mask 100 can be matched to a mask unit region CR of the frame 200. The mask 100 can be matched to the mask unit region CR 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 suction cup 90, it is possible to observe through a microscope whether the mask 100 corresponds to the mask unit region CR. Since the template 50 presses the mask 100, the mask 100 and the frame 200 can be closely abutted.

[0179] On the other hand, a lower support body 70 may be arranged at the lower part of the frame 200. The lower support body 70 has a size that can enter the hollow area R of the frame edge portion 210 and has a flat shape. In addition, 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 body 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 groove, so that the mask unit sheet portion 220 is better fixed.

[0180] The lower support body 70 can press the opposite surface of the mask unit region CR in contact with the mask 100. That is, the lower support body 70 supports the mask unit sheet portion 220 upward, thereby preventing the mask unit sheet portion 220 from sagging downward during the bonding process of the mask 100. At the same time, the lower support body 70 and the template 50 press the edge portion of the mask 100 and the frame 200 (or the mask unit sheet portion 220) in opposite directions to each other, so that the alignment state of the mask 100 is not destroyed and is maintained.

[0181] In this way, the mask 100 can be aligned with the mask unit region CR of the frame 200 only by attaching the mask 100 to the template 50 and loading the template 50 on the frame 200 , and this process does not apply any tensile force to the mask 100 .

[0182] Next, laser L is irradiated to mask 100 to bond mask 100 to frame 200 by laser welding. The welded portion of the laser welded mask generates weld beads WB, which may have the same material as mask 100 / frame 200 and are connected to mask 100 / frame 200 as a whole.

[0183] Fig.17 FIG. 1 is a schematic diagram of a process of separating the mask 100 from the template 50 after the mask 100 is bonded to the frame 200 according to an embodiment of the present invention.

[0184] Reference Fig.17 After the mask 100 is bonded to the frame 200, the mask 100 and the template 50 can be separated (debonding). The separation between the mask 100 and the template 50 can be performed by heating the temporary bonding part 55, chemically treating the temporary bonding part 55, applying ultrasonic waves US, and applying ultraviolet rays UV. Since the mask 100 remains bonded to the frame 200, only the template 50 can be lifted. As an example, if a heat ET higher than 85°C to 100°C is applied, the viscosity of the temporary bonding part 55 decreases, and the bonding force between the mask 100 and the template 50 becomes weak, so that the mask 100 and the template 50 can be separated. As another example, the temporary bonding part 55 is immersed in CM in a chemical substance such as IPA, acetone, and ethanol, and the mask 100 and the template 50 are separated by dissolving and removing the temporary bonding part 55. As another example, if ultrasonic waves US or ultraviolet rays UV are applied, the bonding force between the mask 100 and the template 50 becomes weak, so that the mask 100 and the template 50 can be separated.

[0185] Furthermore, since the temporary bonding part 55 bonding the mask 100 and the template 50 is a TBDB bonding material (temporary bonding & debonding adhesive), various separation methods can be used.

[0186] As an example, a solvent debonding method based on chemical treatment CM can be used. The penetration of solvent dissolves the temporary adhesive portion 55, thereby achieving stripping. At this time, since the pattern P is formed on the mask 100, the solvent will penetrate through the mask pattern P and the interface between the mask 100 and the template 50. The solvent stripping method can be performed at room temperature and does not require other complex stripping equipment, so it is economical compared to other stripping methods.

[0187] As another example, a heat debonding method based on heating ET may be used. The temporary adhesive portion 55 is decomposed by high temperature heat, and if the adhesive force between the mask 100 and the template 50 decreases, the temporary adhesive portion 55 may be debonded in the vertical direction or the horizontal direction.

[0188] As another example, a peelable adhesive debonding method based on heating ET, applying ultraviolet light UV, etc. can be used. If the temporary adhesive portion 55 is a thermal peeling tape, it can be peeled off by the peeling method of peeling adhesive, which, like the thermal peeling method, does not require high-temperature heat treatment equipment and expensive heat treatment equipment and has a relatively simple process.

[0189] As another example, a room temperature debonding method based on chemical treatment CM, application of ultrasonic waves US, application of ultraviolet rays UV, etc. can be used. If a portion (central portion) of the mask 100 or the template 50 is treated with non-sticky treatment, only the edge portion is bonded by the temporary adhesive portion 55. In addition, solvent permeates the edge portion during peeling, so peeling can be achieved by dissolving the temporary adhesive portion 55. This method has the following advantages: during the bonding and peeling process, other parts except the edge area of ​​the mask 100 and the template 50 will not be directly damaged or defects caused by adhesive material residues during peeling will occur. Moreover, this method is different from the thermal peeling method. Since a high-temperature heat treatment process is not required during peeling, it has the advantage of being able to relatively reduce process costs.

[0190] Fig.18 FIG. 1 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.

[0191] Reference Fig.18 , one mask 100 may be bonded to one mask unit region CR of the frame 200 .

[0192] Since the mask unit sheet portion 220 of the frame 200 has a thin thickness, if the mask 100 is bonded to the mask unit sheet portion 220 in a state where a tensile force is applied to the mask 100, the tensile force remaining in the mask 100 acts on the mask unit sheet portion 220 and the mask unit region CR, and may cause deformation. Therefore, the mask 100 should be bonded to the mask unit sheet portion 220 in a state where no tensile force is applied to the mask 100. The present invention can complete the process of matching the mask 100 with the mask unit region CR of the frame 200 by simply attaching the mask 100 to the template 50 and loading the template 50 on the frame 200, and this process does not apply any tensile force to the mask 100. As a result, it is possible to prevent the tensile force applied to the mask 100 from acting in reverse as a tension force on the frame 200, causing the frame 200 (or the mask unit sheet portion 220) to deform.

[0193] Existing Figure 1 The mask 10 of the present invention includes 6 units C1 to C6 and has a longer length, while the mask 100 of the present invention includes one unit C and has a shorter length, so the degree of PPA distortion will be smaller. For example, assuming that the length of the mask 10 including multiple units C1 to C6, ... is 1m, and a PPA error of 10μm occurs in the total length of 1m, the mask 100 of the present invention can change the above error range to 1 / n as the relative length decreases (equivalent to a decrease in the number of units C). For example, if the length of the mask 100 of the present invention is 100mm, the length is reduced from 1m of the existing mask 10 to 1 / 10, so a PPA error of 1μm occurs in the total length of 100mm, which has the effect of significantly reducing the alignment error.

[0194] On the other hand, if the mask 100 has a plurality of cells C and the correspondence of each cell C with each mask cell region CR of the frame 200 is within the range in which the alignment error is minimized, the mask 100 may correspond to a plurality of mask cell regions CR of the frame 200. Alternatively, the mask 100 having a plurality of cells C may correspond to one mask cell region CR. In this case, the mask 100 preferably has as few cells C as possible in consideration of the process time and productivity based on alignment.

[0195] Since the present invention only needs to correspond to one unit C of the mask 100 and confirm the alignment state, it is different from the existing method (refer to Figure 2 ), the manufacturing time can be significantly shortened.

[0196] That is, compared with the existing method of simultaneously matching 6 units C1-C6 and simultaneously confirming the alignment status of the 6 units C1-C6, the manufacturing method of the frame integrated mask of the present invention can significantly shorten the time by making each unit C11-C16 contained in the 6 masks 100 correspond to a mask unit area CR11-CR16 respectively and confirming each alignment status 6 times.

[0197] In addition, in the method for manufacturing the frame-integrated mask of the present invention, the product yield of 30 processes in which 30 masks 100 are respectively aligned with 30 mask unit regions CR (CR11-CR56) is significantly higher than that of 5 masks 100 (refer to FIG. Figure 2 (a)) corresponds to and aligns with the frame 200 for 5 times. Since the existing method of aligning 6 cells C1-C6 in the area corresponding to 6 cells C each time is obviously cumbersome and difficult, the product yield is low.

[0198] On the other hand, Fig.12 In (b), as described above, when the mask metal film 110 is bonded to the template 50 by the 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 bonded to the template 50 with a partial tensile force applied thereto. Then, the mask 100 is bonded to the frame 200, and if the mask 100 is separated from the template 50, the mask 100 will shrink to a predetermined degree.

[0199] If the template 50 is separated from the mask 100 after each mask 100 is bonded to the corresponding mask unit region CR, the plurality of masks 100 apply contraction tension in opposite directions, so the force is offset, and the mask unit sheet portion 220 will not be deformed. For example, in the first grid sheet portion 223 between the mask 100 attached to the mask unit region CR11 and the mask 100 attached to the mask unit region CR12, the tension acting in the right direction of the mask 100 attached to the mask unit region CR11 and the tension acting in the left direction of the mask 100 attached to the mask unit region CR12 are offset. As a result, the deformation of the frame 200 (or the mask unit sheet portion 220) caused by the tension is minimized, so that the alignment error of the mask 100 (or the mask pattern P) can be minimized.

[0200] Fig.19 FIG. 1 is a schematic diagram of an OLED pixel deposition apparatus 1000 using frame-integrated masks 100 and 200 according to an embodiment of the present invention.

[0201] Reference Fig.19The OLED pixel deposition device 1000 includes: a magnetic plate 300 accommodating a magnet 310 and provided with a cooling water pipe 350 ; and a deposition source supplying part 500 supplying an organic source 600 from a lower portion of the magnetic plate 300 .

[0202] A target substrate 900 such as glass for depositing the organic source 600 may be inserted between the magnetic plate 300 and the deposition source supply unit 500. A frame-integrated mask 100, 200 (or FMM) for depositing the organic source 600 according to different pixels may be arranged in close contact or very close to the target substrate 900. The magnet 310 may generate a magnetic field and be closely attached to the target substrate 900 through the magnetic field.

[0203] The deposition source supply unit 500 can reciprocate the left and right paths and supply the organic source 600. The organic source 600 supplied by the deposition source supply unit 500 can be deposited on one side of the target substrate 900 after passing through the pattern P formed on the frame-integrated mask 100, 200. The organic source 600 deposited after passing through the pattern P of the frame-integrated mask 100, 200 can be used as a pixel 700 of an OLED.

[0204] In order to prevent uneven deposition of the pixels 700 due to the shadow effect, the pattern of the frame-integrated mask 100, 200 may be formed obliquely S (or formed in a tapered S). The organic source 600 passing through the pattern in a diagonal direction along the inclined surface facilitates the formation of the pixels 700, so that the pixels 700 can be deposited with uniform thickness as a whole.

[0205] The mask 100 is bonded and fixed to the frame 200 at a first temperature higher than the pixel deposition process temperature, so even if the temperature is raised to the temperature for the pixel deposition process, the position of the mask pattern P is hardly affected, and the PPA between the mask 100 and the adjacent mask 100 can be maintained at no more than 3μm.

[0206] As described above, although the preferred embodiments of the present invention are described with reference to the accompanying drawings, the present invention is not limited to the embodiments, and a person skilled in the art of the present invention may make various modifications and changes to the embodiments without departing from the spirit of the present invention. The modifications and changes should be deemed to fall within the scope of the present invention and the appended claims.

Claims

1. A method for manufacturing a mask support template, wherein the mask support template is used to adhere and support a mask for forming OLED pixels and transfer it to a frame, and after the mask is attached corresponding to the frame, the template is separated from the mask, wherein: The manufacturing method comprises the following steps: (a) providing a mask metal film; (b) bonding the mask metal film to a template having a temporary bonding portion formed on a surface thereof; and (c) forming a mask pattern on the mask metal film to manufacture a mask, The step (c) comprises the following steps: (c1) forming a patterned insulating portion on the mask metal film; (c2) etching the portion of the mask metal film exposed between the insulating portions to form a mask pattern; and (c3) Remove the insulating portion.

2. The method for manufacturing a mask support template according to claim 1, wherein: When the mask metal film is produced by electroforming, step (a) comprises the following steps: (a1) forming a mask metal film on at least one surface of a conductive single crystal substrate; and (a2) Separating the mask metal film from the conductive single crystal substrate.

3. The method for manufacturing a mask support template according to claim 1, wherein: The temporary adhesive portion is an adhesive or adhesive sheet that is removable by heating, or an adhesive or adhesive sheet that is removable by irradiating ultraviolet rays.

4. The method for manufacturing a mask support template according to claim 1, wherein: The temporary bonding portion is formed on the entire surface of one surface of the template, and the mask metal film is bonded to the entire surface of the temporary bonding portion.

5. The method for manufacturing a mask support template according to claim 1, wherein: The material of the template includes any one of wafer, glass, silicon dioxide, heat-resistant glass, quartz, alumina, borosilicate glass, and zirconium oxide.

6. A mask support template for supporting and bonding a mask for forming OLED pixels and transferring it to a frame, and separating the template from the mask after the mask is attached corresponding to the frame, wherein: include: template; a temporary bonding portion formed on the template; as well as a mask, which is bonded to the template by a temporary bonding portion and is formed with a mask pattern, The temporary bonding portion is formed on the entire surface of one surface of the template, and the mask metal film is bonded to the entire surface of the temporary bonding portion, and the temporary bonding portion is an adhesive or adhesive sheet that can be separated by heating, or an adhesive or adhesive sheet that can be separated by irradiating ultraviolet rays, The position of the template is controlled so that the mask corresponds to the frame. After the mask is attached to the frame, heat or ultraviolet rays are applied to the temporary adhesive portion of the template to weaken the adhesive force of the temporary adhesive portion of the template, thereby separating the template from the mask attached to the frame.

7. The mask support template according to claim 6, wherein: A laser passage hole is formed in a portion of the template corresponding to the welding portion of the mask.

8. The mask support template according to claim 6, wherein: The material of the template includes any one of wafer, glass, silicon dioxide, heat-resistant glass, quartz, alumina, borosilicate glass, and zirconium oxide.

9. The mask support template according to claim 6, wherein: The mask includes a mask unit on which a plurality of mask patterns are formed and a dummy portion around the mask unit.

10. A method for manufacturing a frame-integrated mask, wherein the frame-integrated mask is formed as a whole by at least one mask and a frame for supporting the mask, wherein: The manufacturing method comprises the following steps: (a) providing a mask metal film; (b) bonding the mask metal film to a template having a temporary bonding portion formed on a surface thereof; (c) forming a mask pattern on the mask metal film to manufacture a mask; (d) providing a frame having at least one mask unit region; (e) loading the template onto the frame so that the mask corresponds to the mask unit area of ​​the frame; and (f) irradiating a laser beam to a welding portion of the mask so that the mask is bonded to the frame, The step (c) comprises the following steps: (c1) forming a patterned insulating portion on the mask metal film; (c2) etching the portion of the mask metal film exposed between the insulating portions to form a mask pattern; and (c3) Removing the insulating part, The method further includes, after step (f), performing at least one of heating, chemical treatment, application of ultrasound, and application of ultraviolet light to the temporary adhesive portion, thereby separating the mask from the template.

11. The method for manufacturing a frame-integrated mask according to claim 10, wherein: Step (d) comprises the following steps: (d1) providing an edge frame portion including a hollow area; (d2) connecting the planar mask unit sheet portion to the edge frame portion; and (d3) A plurality of mask unit regions are formed on the mask unit sheet portion to produce a frame.

12. The method for manufacturing a frame-integrated mask according to claim 10, wherein: Step (d) comprises the following steps: (d1) providing an edge frame portion including a hollow area; and (d2) Connecting a mask unit sheet portion having a plurality of mask unit areas to an edge frame portion to manufacture a frame.

13. The method for manufacturing a frame-integrated mask according to claim 10, wherein: The temporary adhesive portion is an adhesive or adhesive sheet that is removable by heating, or an adhesive or adhesive sheet that is removable by irradiating ultraviolet rays.

14. The method for manufacturing a frame-integrated mask according to claim 10, wherein: The laser light irradiated from the upper portion of the template passes through the laser passing hole and irradiates the welding portion of the mask.

15. The method for manufacturing a frame-integrated mask according to claim 10, wherein: The mask and the frame are made of any one of Invar alloy, Super Invar alloy, Nickel, and Nickel-Cobalt.

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