TW202108790A - Template for supporting mask, producing method of template for supporting mask and producing method of mask integrated frame - Google Patents

Abstract

The invention relates to a mask support template, a method for manufacturing the mask support template, and a method for manufacturing a frame-integrated mask. The mask support template of the invention is used to support an OLED pixel forming mask and apply the mask to a frame. The mask support template includes a template, a temporary bonding part formed on the template, and a mask adhered to the template through a temporary bonding part and formed with a mask pattern.

Description

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

Invention field

The invention relates to a mask support template, a method for manufacturing a mask support template, and a method for manufacturing a frame-integrated mask. More specifically, the present invention relates to a mask support template, a method for manufacturing a mask support template, and a frame that enables the mask to not deform, can be stably supported and moved, and can accurately align each mask. Manufacturing method of integrated mask.

Background of the invention

As a technology for forming pixels in the OLED manufacturing process, the FMM (Fine Metal Mask) method is mainly used, which attaches a thin-film metal mask (Shadow Mask) to the substrate and is Evaporate organic matter on the 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 evaporation frame and used. One mask may have a plurality of cells corresponding to one display. In addition, in order to manufacture a large-area OLED, a plurality of masks can be fixed to the OLED pixel evaporation frame, and in the process of fixing to the frame, each mask is stretched to make it flat. It is a very difficult task to adjust the stretching force to flatten the entire part of the mask. Especially in order to flatten each cell and align the mask pattern with a size of several to tens of μm, it is necessary to perform the following difficult work: finely adjust the tensile force applied to each side of the mask while checking immediately Alignment status.

Nevertheless, in the process of fixing a plurality of masks to a 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 of the mask sagging or twisting due to the load; due to wrinkles and burrs generated in the welding part during the welding process (burr), etc., causing the problem of inaccurate alignment of the mask unit.

Among the ultra-high-quality OLEDs, the existing QHD image quality is 500-600PPI (pixel per inch, pixels per inch), and the pixel size reaches about 30-50μm, while 4K UHD and 8K UHD have higher image quality. Resolutions of ~860PPI, ~1600PPI, etc. In this way, considering the pixel size of the ultra-high-quality OLED, the alignment error between each unit needs to be reduced to a few μm. Exceeding this error will lead to product failure, so the yield may be extremely low. Therefore, it is necessary to develop a technique that can prevent deformation such as sagging or twisting of the mask and make the alignment accurate, and a technique that fixes the mask to the frame, and the like.

technical problem

Therefore, the present invention is proposed in order to solve the various problems of the prior art as described above, and its object is to provide a mask that can be supported and moved stably without deformation, and can prevent the mask from sagging or twisting. The mask support template, the manufacturing method of the mask support template and the manufacturing method of the frame-integrated mask can be accurately aligned.

In addition, an 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. Technical solutions

The above-mentioned object of the present invention is achieved by a mask support template, which is used to support the OLED pixel forming mask and correspond to the mask on the frame. The mask support template includes: a template; a temporary bonding part, It is formed on a template; and a mask, which is adhered to the template by interposing a temporary adhesive part and is formed with a mask pattern, and the thermal expansion coefficient of the template is lower than that of the mask.

The thermal expansion coefficient of the mask may be at least greater than 1.

The thermal expansion coefficient of the template can be less than 1 (greater than 0).

The temporary adhesive part may be an adhesive that can be separated by heating or an adhesive that can be separated by UV irradiation.

The temporary bonding part may be liquid wax.

At room temperature, the mask can be adhered to the template by applying a tensile force in the lateral direction.

In addition, the above-mentioned object of the present invention is achieved by a method for manufacturing a mask support template, which is used to support the OLED pixel forming mask and correspond to the mask on the frame, the method includes: (a) preparing a surface with The step of temporarily bonding the template of the part; (b) the step of raising the process temperature to at least higher than normal temperature and bonding the mask metal film to the template; (c) the step of lowering the process temperature; and (d) the step of In the step of forming a mask pattern on the mask metal film to manufacture the mask, the thermal expansion coefficient of the template is lower than that of the mask.

The thermal expansion coefficient of the mask may be at least greater than 1, and the thermal expansion coefficient of the template may be less than 1 (greater than 0).

The temporary adhesive part may be an adhesive that can be separated by heating or an adhesive that can be separated by UV irradiation.

The temporary bonding part may be liquid wax.

If the process temperature is lowered in step (a), the shrinkage of the template will be smaller than the shrinkage of the mask, so that the mask can be applied with a tensile force in the lateral direction.

In addition, the above-mentioned object of the present invention is achieved by a method for manufacturing a mask support template, which is used to support the OLED pixel forming mask and correspond to the mask on the frame, the method includes: (a) preparing a surface with The step of temporarily bonding the template of the part; (b) the step of raising the process temperature to at least higher than normal temperature, and bonding the mask with the mask pattern formed on the template; and (c) the step of lowering the process temperature, the template The coefficient of thermal expansion is lower than that of the mask.

In addition, the above-mentioned object of the present invention is achieved by a method for manufacturing a frame-integrated mask. The frame-integrated mask is integrally formed by at least one mask and a frame for supporting the mask. The method includes: (a) preparing a surface The step of forming the template with the temporary bonding part; (b) the step of raising the process temperature to at least higher than normal temperature and bonding the mask metal film to the template; and (c) the step of lowering the process temperature; (d) A step of manufacturing a mask by forming a mask pattern on a mask metal film; (e) a step of loading a template on a frame having at least one mask unit area, and corresponding the mask to the mask unit area of the frame And (f) the step of attaching the mask to the frame, the thermal expansion coefficient of the template is lower than that of the mask. In addition, the above-mentioned object of the present invention is achieved by a method for manufacturing a frame-integrated mask. The frame-integrated mask is integrally formed by at least one mask and a frame for supporting the mask. The method includes: (a) The step of loading the template with the mask bonded onto the frame having at least one mask unit area, and corresponding the mask to the mask unit area of the frame; and (b) the step of attaching the mask to the frame, the template The coefficient of thermal expansion is lower than that of the mask. Beneficial effect

According to the present invention having the above-mentioned structure, the mask can be supported and moved stably without deformation, and the mask can be prevented from being deformed such as sagging or twisting and can be accurately aligned. In addition, according to the present invention, it is possible to significantly shorten the manufacturing time and significantly improve the yield.

Detailed ways

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings, which are used to illustrate examples of specific embodiments that can be implemented as the present invention. These embodiments are described in detail so that those skilled in the art can fully implement the present invention. The various embodiments of the present invention should be understood to be different from each other but not mutually exclusive. For example, the specific shapes, structures, and characteristics described herein can implement one embodiment into other embodiments without departing from the spirit and scope of the present invention. In addition, the position or arrangement of the individual component elements in each disclosed embodiment should be understood to be changeable without departing from the spirit and scope of the present invention. Therefore, the following detailed description is not intended to limit the present invention, as long as it can be appropriately described, the scope of the present invention is limited only by the scope of the attached patent application and all the scopes equivalent thereto. Similar reference numerals in the drawings refer to the same or similar functions in various aspects. For convenience, the length, area, thickness, etc. and their forms can also be exaggerated.

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

Fig. 1 is a schematic diagram of an existing process of attaching a mask to a frame.

The existing mask 10 is a stick-type or a plate-type. The strip-type mask 10 in FIG. 1 can be used by welding and fixing both sides of the strip to the OLED pixel evaporation frame. The main body (body, or mask film 11) of the mask 10 is provided with a plurality of display units C. One cell C corresponds to one display of a smart phone or the like. A pixel pattern P is formed in the cell C so as to correspond to each pixel of the display.

Referring to Fig. 1(a), a tensile force F1-F2 is applied along the long axis direction of the strip mask 10, and the strip mask 10 is mounted on a box-shaped frame 20 in an unfolded state. The cells C1 to C6 of the strip mask 10 will be located in the blank area part of the frame of the frame 20.

1(b), the tensile force F1-F2 applied to each side of the strip mask 10 is fine-tuned while alignment is performed, and then a part of the side of the W strip mask 10 is welded to make the strip mask 10 And the frame 20 are connected to each other. (C) of FIG. 1 shows a side section of the strip mask 10 and the frame connected to each other.

Although the tensile forces F1-F2 applied to each side of the strip mask 10 are fine-tuned, the problem of poor alignment of the mask units C1-C3 with each other still occurs. For example, the distances between the patterns P of the cells C1-C6 are different from each other or the patterns P are skewed. Since the strip mask 10 has a large area including a plurality of cells C1-C6, and has a very thin thickness of several tens of μm, it is likely to sag or twist due to a load. In addition, while adjusting the tensile force F1-F2 to make all the units C1-C6 flat, it is a very difficult task to check the alignment state of the units C1-C6 in real time through a microscope. However, in order to prevent the mask pattern P with a size of several μm to several tens of μm from adversely affecting the pixel process of the ultra-high-quality OLED, the alignment error is preferably not more than 3 μm. The alignment error between such adjacent cells is referred to as pixel position accuracy (PPA).

Furthermore, each strip mask 10 is connected to a frame 20, and at the same time, the alignment state between the strip masks 10 and the cells C-C6 of the strip mask 10 is accurately Very difficult operation, and will only increase the process time based on alignment, which becomes an important reason for reducing production efficiency.

In addition, after the strip mask 10 is connected and fixed to the frame 20, the tensile forces F1-F2 applied to the strip mask 10 will act on the frame 20 in reverse. This tension causes the frame 20 to be slightly deformed, and there is a problem that the alignment state between the multiple units C-C6 is distorted.

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 can not only prevent deformation such as sagging or twisting, but also can be accurately aligned with the frame 200.

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

Hereinafter, although this specification describes the configuration of the frame-integrated mask, the structure and manufacturing process of the frame-integrated mask can be understood to include all the contents of Korean Patent Application No. 2018-0016186.

Referring to FIG. 2, the frame-integrated mask may include a plurality of masks 100 and one frame 200. In other words, it is a form in which a plurality of masks 100 are attached to the frame 200, respectively. In the following, for the convenience of description, a square mask 100 is used as an example for description. However, before the mask 100 is attached to the frame 200, it may be in the shape of a stripe mask with protrusions for clamping on both sides and attached to the frame. After 200, the protrusion can be removed.

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

The mask 100 may also be made of invar, super invar, nickel (Ni), nickel-cobalt (Ni-Co) and other materials. The mask 100 may use a metal sheet produced by a rolling process or electroforming. A detailed description will be given later with reference to FIGS. 9 and 10.

The frame 200 may be formed in a form in which a plurality of masks 100 are attached. In consideration of thermal deformation, the frame 200 is preferably formed of materials such as Invar, Super Invar, nickel, nickel-cobalt, etc., which have the same thermal expansion coefficient as the mask. The frame 200 may include an edge frame portion 210 having a substantially quadrangular shape and a box shape. The inside of the edge frame part 210 may be hollow.

In addition, the frame 200 is provided with a plurality of mask cell regions CR, and may include a mask cell sheet part 220 connected to the edge frame part 210. The mask unit sheet part 220 may be composed of an edge sheet part 221, a first grid sheet part 223 and a second grid sheet part 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 integral with each other.

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

In the flat 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-CR56) may be provided.

The mask 200 includes a plurality of mask cell regions CR, and each mask 100 can be attached such that each mask cell C corresponds to each mask cell region CR. The mask unit C corresponds to the mask unit region CR of the frame 200, and a part or all of the dummy part may be attached to the frame 200 (mask unit sheet part 220). Therefore, the mask 100 and the frame 200 may form an integrated structure.

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

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 mask 100 may be manufactured using a metal sheet produced by a rolling process, electroforming, or the like, and a cell C may be formed in the mask 100. The dummy portion DM corresponds to the mask film 110 [mask metal film 110] except for the cell C, and may include only the mask film 110, or include a predetermined dummy portion pattern formed with a form similar to the mask pattern P Mask film 110. The dummy part DM corresponds to the edge of the mask 100 and part or all of the dummy part DM may be attached to the frame 200 [mask unit sheet part 220].

The width of the mask pattern P may be less than 40㎛, and the thickness of the mask 100 may be about 5-20㎛. Since the frame 200 is provided with a plurality of mask cell regions CR (CR11-CR56), it may also be provided with a plurality of masks 100 having a mask cell corresponding to each mask cell region CR (CR11-CR56) C(C11-C56).

Referring to FIG. 4(a), a template 50 (template) may be provided. The template 50 is a medium on which the mask 100 is attached to one surface and the mask 100 is moved while supporting the mask 100. One surface of the template 50 is preferably a flat surface to support and carry the flat mask 100. The central part 50a may correspond to the mask unit C of the mask metal film 110, and the edge part 50b may correspond to the dummy part DM of the mask metal film 110. In order to be able to support the mask metal film 110 as a whole, the template 50 has a flat shape having an area larger than that of the mask metal film 110.

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

The position and the number of the laser passing holes 51 do not necessarily correspond to the position and the number of the welding part WP. For example, only part of the laser passing holes 51 may be irradiated with the laser light L to perform welding. In addition, the part of the laser passing hole 51 that does not correspond to the welding portion WP 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 light L, the laser light passing hole 51 may not be formed.

A temporary bonding part 55 may be formed on one side of the template 50. Before the mask 100 is attached to the frame 200, the temporary adhesive part 55 may temporarily attach the mask 100 [or the mask metal film 110] to one side of the template 50 and support it on the template 50.

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

As an example, the temporary bonding part 55 may use liquid wax. The liquid wax can be the same wax used in the polishing step of the semiconductor wafer, etc., and its type is not particularly limited. As a resin component mainly used to control adhesion and impact resistance related to maintaining power, liquid wax may include substances and solvents such as acrylic acid, vinyl acetate, nylon, and various polymers. As an example, the temporary adhesive part 55 may use SKYLIQUIDABR-4016 including Acrylonitrile butadiene rubber (ABR) as a resin component and n-propanol as a solvent component. A spin coating method is used to form liquid wax on the temporary bonding part 55.

The temporary adhesive part 55, which is a liquid wax, decreases in viscosity at a temperature higher than 85°C to 100°C, and increases in viscosity at a temperature lower than 85°C, and a part of it is solidified to solidify the mask metal film 110. 'Fixed and bonded to the template 50.

Next, referring to FIG. 4(b), the mask metal film 110' may be bonded on the template 50. The liquid wax may be heated to 85°C or higher, and the mask metal film 110' may be brought into contact with the template 50, and then the mask metal film 110' and the template 50 may be passed between the rollers for bonding.

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

Next, referring further to Fig. 4(b), one surface of the mask metal film 110' may be planarized PS. The mask metal film 110' manufactured by the rolling process can be reduced in thickness by the planarization PS process (110'→110). In addition, in order to control the surface characteristics and thickness, the mask metal film 110 manufactured by the electroforming process may also be subjected to a planarization PS process.

Therefore, as shown in (c) of FIG. 4, as the thickness of the mask metal film 110' decreases (110'→110), the thickness of the mask metal film 110 may be about 5㎛ to 20㎛.

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

Next, the mask metal film 110 may be etched. Methods such as dry etching, wet etching, etc. can be used without limitation, and as a result of the etching, the portion of the mask metal film 110 exposed from the blank space 26 between the insulating portions 25 can be etched away. The etched portion of the mask metal film 110 forms a mask pattern P, so that the mask 100 in which a plurality of mask patterns P are formed can be manufactured.

Then, referring to FIG. 5( e ), the manufacturing of the template 50 supporting the mask 100 can be completed by removing the insulating portion 25.

In addition, although the process of forming the mask pattern P after bonding the mask metal film 110 to the template 50 is described in (d) and (e) of FIG. 5, it is not limited to this, and the mask formed with the mask pattern P may be used. The mold 100 [refer to FIG. 3] is adhered to the template 50, thereby ending the manufacture of the template 50 for supporting the mask 100.

Since the frame 200 has a plurality of mask cell regions CR (CR11-CR56), it may also have a plurality of masks 100 having a mask cell corresponding to each mask cell region CR (CR11-CR56) C(C11-C56). In addition, there may be a plurality of templates 50 for supporting each of the plurality of masks 100 respectively.

FIG. 6 is a schematic diagram of the problem when the thermal expansion coefficient of the template according to the comparative example is higher than that of the mask.

6(a), the process temperature of the space where the bonding process of the mask metal film 110 [or the mask 100] and the template 50' is performed is increased to a temperature T1 higher than the normal temperature. The process temperature T1 may be 85° C. to 100° C. to reduce the viscosity of the temporary bonding portion 55 described above. Next, the solvent of the temporary bonding part 55 is vaporized by baking, and the mask metal film 110 is bonded to the template 50'. Then, the process temperature can be lowered to a temperature T2 at which the viscosity of the temporary bonding part 55 becomes large and a part can be solidified into a solid.

In the past, glass, borosilicate glass, etc. have been used as the material of the template 50'. ^{Among them, the thermal expansion coefficient of BOROFLOAT ®} 33, which is especially borosilicate glass, is about 3.3 × 10-6/℃, which is comparable to an invar mask with a thermal expansion coefficient of about 1.5-3 × 10-6/℃. The difference in thermal expansion coefficient of the metal film 110 is small, and it is easy to control the mask metal film 110, so it is often used.

The thermal expansion coefficient of the template 50' is higher than that of the mask metal film 110. When the temperature T2 is lowered as shown in FIG. 6(a), the degree of contraction L2 of the mask metal film 110 based on the temperature change is relatively small. On the contrary, the template 50 'The degree of relative contraction L1 (L1>L2) is large. At the same time, the template 50' and the mask metal film 110 are firmly bonded and fixed with the temporary adhesive part 55 interposed therebetween, and the mask metal film 110 is applied with a force CT that shrinks more than the original shrinkage degree L2. . The force CT to shrink more is generated because the degree L1 of shrinkage of the template 50' is greater than the degree L2 of shrinkage of the mask metal film 110. Therefore, the mask metal film 110 is adhered to the template 50' in a state where the compressive force CT in the side direction [inside of the mask metal film 110] is applied.

If the thermal expansion coefficient of the template 50' is higher than that of the mask 100 [or the mask metal film 110], the following problems may occur.

6(b), the template 50' of FIG. 6(a) is loaded on the frame 200 [or the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225] It corresponds to the mask 100, and the solder beads WB are formed by welding, so that the mask 100 can be attached to the frame 200.

In addition, the template 50' can be separated from the mask 100. However, the compressive force CT applied to the mask 100 while separating the template 50' from the mask 100 is released, thereby causing the alignment state of the mask 100 to be disturbed. In other words, there may be a problem that the mask 100 cannot be attached to the frame 200 in a state in which both sides of the mask 100 are pulled tightly toward the outside, but is attached to the frame 200 in a wrinkled or sagging state. This will cause product defects based on the alignment error of the mask 100, the PPA error between the cells C, and the like.

Therefore, the template 50 of the present invention has a feature that the coefficient of thermal expansion is lower than that of the mask 100 [or the mask metal film 110].

7 is a schematic diagram of the interface state between the mask and the tray and the state of the mask attached to the frame when the thermal expansion coefficient of the template is lower than that of the mask according to an embodiment of the present invention.

7(a), as shown in FIG. 6(a), the process temperature of the space is raised to a temperature T1 higher than normal temperature, and the mask metal film 110 [or the mask 100 after the formation of the pattern P is completed] is bonded to the template 50 up. Then, the process temperature can be lowered to a temperature T2 at which the viscosity of the temporary adhesive part 55 becomes large and a part of the temporary adhesive part 55 can be solidified into a solid.

The mask metal 110 [or the mask 100] is a material such as Invar, Super Invar, nickel, nickel-cobalt, etc., with a thermal expansion coefficient of at least greater than 1. Conversely, the thermal expansion coefficient of the template 50 may be less than 1 (greater than 0). Preferably, a template 50 of quartz material with a thermal expansion coefficient of 0.55 may be used, but it is not limited thereto.

Since the thermal expansion coefficient of the template 50 is lower than that of the mask metal film 110, when the temperature T2 is lowered as shown in (a) of FIG. Although the degree of shrinkage of the mask metal film 110 [L2 degree of shrinkage in FIG. 7(a)] is relatively large, it cannot shrink because it is firmly bonded and fixed to the template 50 by interposing the temporary adhesive portion 55. And the internal force IT that wants to contract is applied. In other words, the mask metal film 110 is applied with a lateral tensile force IT and adhered to the template 50 in a tight state.

7(b), the template 50 is loaded on the frame 200 [or the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225] in the state of FIG. 6(a) , And corresponding to the mask 100, and solder beads WB are formed by welding, so that the mask 100 can be adhered to the frame 200.

In addition, the template 50 can be separated from the mask 100. However, the tensile force IT applied to the mask 100 while separating the template 50' from the mask 100 is released and converted into a tension TS that tightens both sides of the mask 100. In other words, this state is a state in which the mask 100 is pulled to a length longer than the length at the original lower temperature T2 of the mask 100 and then bonded to the template 50. Since in this state, it is welded and bonded to the frame 200 intact. Therefore, it is possible to maintain the pulled state [the state where the tension TS is applied to the surrounding mask unit sheet portion 220 by itself]. The mask 100 is attached to the frame 200 in a tightly pulled state, so that wrinkles, deformation, etc. do not occur. Therefore, there is an effect of reducing the alignment error of the mask 100 and the PPA error between the cells C.

FIG. 8 is a schematic diagram of a state where the template 50 is loaded on the frame 200 and the mask 100 is corresponding to the cell area CR of the frame 200 according to an embodiment of the present invention. FIG. 8 illustrates the method of corresponding/attaching one mask 100 to the cell region CR. It is also possible to simultaneously map multiple masks 100 to all the cell regions CR and attach the mask 100 to the frame 200. At this time, there may be a plurality of templates 50 for supporting each of the plurality of masks 100 respectively.

The template 50 can be transferred by a vacuum chuck 90. The vacuum chuck 90 can be used to suck and transfer the opposite surface of the surface to which the template 50 of the mask 100 is adhered. The vacuum chuck 90 sucks and turns the template 50 and transfers the template 50 to the frame 200 without affecting the adhesion state and alignment state of the mask 100.

Next, referring to FIG. 8, the mask 100 can be mapped to a mask unit area CR of the frame 200. By loading the template 50 on the frame 200 [or the mask unit sheet part 220], the mask 100 can be corresponded to the mask unit region CR. While controlling the position of the template 50/vacuum chuck 90, it is possible to observe through a microscope whether the mask 100 corresponds to the mask unit area CR. Since the template 50 presses the mask 100, the mask 100 can be closely attached to the frame 200.

In addition, a lower support body 70 may be further arranged in the lower part of the frame 200. The lower support 70 may press the reverse surface of the mask unit region CR that is in contact with the mask 100. At the same time, since the lower support 70 and the template 50 press the edges of the mask 100 and the frame 200 [or the mask unit sheet portion 220] in opposite directions, the alignment state of the mask 100 can be maintained without Was disrupted.

Next, the mask 100 is irradiated with laser light L and the mask 100 is attached to the frame 200 based on laser welding. A welding bead WB is generated on the welding part WP part of the mask welded by the laser, and the welding bead WB may have the same material as the mask 100/frame 200 and be integrally connected with them.

FIG. 9 is a schematic diagram of a process of separating the mask from the template after attaching the mask to the frame according to an embodiment of the present invention.

9, after the mask 100 is attached to the frame 200, the mask 100 and the template 50 may be debonded. The separation of the mask 100 and the template 50 may be performed by at least any one of heating ET, chemical treatment CM, applying ultrasonic waves US, and applying ultraviolet UV to the temporary bonding part 55. Since the mask 100 remains attached to the frame 200, only the template 50 can be lifted. As an example, if the heat ET at a temperature higher than 85° C.-100° C. is applied, the viscosity of the temporary bonding part 55 decreases, and the adhesion between the mask 100 and the template 50 is weakened, so that the mask 100 and the template 50 can be separated. As another example, the mask 100 can be separated from the template 50 by immersing the temporary bonding part 55 in CM such as IPA, acetone, ethanol, etc. to dissolve or remove the temporary bonding part 55. As another example, the adhesive force between the mask 100 and the template 50 is weakened by applying ultrasonic waves US or applying ultraviolet rays, so that the mask 100 and the template 50 can be separated.

If the template 50 is separated from the mask 100, the tensile force IT applied to the mask 100 can be converted into a tension TS for tightening both sides of the mask 100 while being released. Thereby, the mask 100 can be attached in a tight state by applying tension TS to the frame 200 [mask unit sheet part 220].

FIG. 10 is a schematic diagram of a state where the mask 100 is attached to the frame 200 according to an embodiment of the present invention. The state where all the masks 100 are attached to the cell region CR of the frame 200 is illustrated in FIG. 10. Although the templates 50 can be separated after the masks 100 are attached one by one, it is also possible to separate all the templates 50 after all the masks 100 are attached.

The existing mask 10 of FIG. 1 includes 6 cells C1-C6, and therefore has a relatively long length, while the mask 100 of the present invention includes one cell C and therefore has a relatively short length, and therefore PPA (pixel position accuracy) is distorted. The degree will become smaller. Moreover, the present invention only needs to correspond to one cell C of the mask 100 and confirm the alignment state. Therefore, compared with the existing method that simultaneously corresponds to multiple cells C (C1-C6) and needs to confirm all the alignment states, the present invention The invention can significantly shorten the manufacturing time.

If each mask 100 is attached to the corresponding mask unit area CR and then the template 50 is separated from the mask 100, the tensions TS that shrink in opposite directions are applied by the plurality of masks 100, and the tensions cancel each other out Therefore, the mask unit sheet portion 220 will not be deformed. For example, on the first grid sheet portion 223 between the mask 100 attached to the CR11 cell area and the mask 100 attached to the CR12 cell area, the mask 100 attached to the CR11 cell area acts on the right side. The tension TS and the tension TS acting in the left direction of the mask 100 attached to the CR12 cell area can cancel each other out. Therefore, the deformation of the frame 200 [or the mask unit sheet portion 220] due to the tension TS is minimized, thereby having an advantage of minimizing the alignment error of the mask 100 [or the mask pattern P].

As described above, the present invention exemplifies preferred embodiments for illustration and description, but the present invention is not limited to the above-mentioned embodiments, and those skilled in the art can make various modifications and changes within the scope not departing from the spirit of the present invention. Such deformations and changes are within the scope of the present invention and the attached patent application.

10,100: mask 11,110,110’: Mask film, mask metal film 20,200: frame 25: Insulation part 26: Blank space 50,50’: template 50a: Center 50b: Edge 51: Laser through hole 55: Temporary bonding part 70: Lower support 90: vacuum suction cup 210: Edge frame part 220: Mask unit sheet section 221: Edge sheet section 223: The first grid sheet part 225: The second grid sheet part C, C1-C6, C11-C56: unit, mask unit CR, CR11-CR56: Mask unit area CM: Chemical treatment CT: contraction force, compression force DM: dummy part, mask dummy part ET: heating F1-F2: Stretching force L: Laser L1, L2: the degree of contraction IT: internal force, tensile force P: Mask pattern PS: Flattening T1, T2: temperature TS: Tension W: welding WB: Solder bead WP: Welding Department US: Ultrasound UV: Ultraviolet

Fig. 1 is a schematic diagram of an existing process of attaching a mask to a frame. Fig. 2 is a front view and a side sectional view of a frame-integrated mask according to an embodiment of the present invention. Fig. 3 is a schematic diagram of a mask according to an embodiment of the present invention. 4 to 5 are schematic diagrams of a process of forming a mask by bonding a mask metal film on a template to manufacture a mask support template according to an embodiment of the present invention. FIG. 6 is a schematic diagram of the problem when the thermal expansion coefficient of the template according to the comparative example is higher than that of the mask. 7 is a schematic diagram of the interface state between the mask and the tray and the state of the mask attached to the frame when the thermal expansion coefficient of the template is lower than that of the mask according to an embodiment of the present invention. Fig. 8 is a schematic diagram of a state in which a template is loaded on a frame and corresponds to a unit area of the frame according to an embodiment of the present invention. 9 is a schematic diagram of a process of separating the mask and the template after attaching the mask to the frame according to an embodiment of the present invention. FIG. 10 is a schematic diagram of a state in which a mask is attached to a unit area of a frame according to an embodiment of the present invention.

50: template

55: Temporary bonding part

100: mask

110: Mask film, mask metal film

200: frame

210: Edge frame part

221: Edge sheet section

L2: The degree of contraction

IT: Internal force, tensile force

T1, T2: temperature

TS: Tension

WB: Solder bead

Claims (14)

A mask support template for supporting a mask for forming OLED pixels and corresponding the mask to a frame, the mask support template comprising: template; Temporary bonding part, which is formed on the template; and A mask, which is adhered to the template by interposing a temporary adhesive part and a mask pattern is formed, The thermal expansion coefficient of the template is lower than that of the mask. The mask support template according to claim 1, wherein the thermal expansion coefficient of the mask is at least greater than 1. The mask support template according to claim 1, wherein the thermal expansion coefficient of the template is less than 1 (greater than 0). The mask support template according to claim 1, wherein the temporary bonding part is an adhesive that can be separated by heating and an adhesive that can be separated by irradiation with UV. The mask support template according to claim 4, wherein the temporary bonding part is liquid wax. The mask support template according to claim 1, wherein the mask is adhered to the template in a state where a lateral tensile force is applied to the mask at room temperature. A method for manufacturing a mask support template, the template being used to support a mask for forming an OLED pixel and corresponding the mask to a frame, the method comprising: (a) The step of preparing a template with a temporary bonding part formed on one side; (b) The step of raising the process temperature to at least higher than normal temperature and bonding the mask metal film to the template; (c) Steps to lower the process temperature; and (d) A step of manufacturing a mask by forming a mask pattern on a mask metal film, The thermal expansion coefficient of the template is lower than that of the mask. The method for manufacturing a mask support template according to claim 7, wherein the thermal expansion coefficient of the mask is at least greater than 1, and the thermal expansion coefficient of the template is less than 1 (greater than 0). The method for manufacturing a mask support template according to claim 7, wherein the temporary bonding part is an adhesive that can be separated by heating and an adhesive that can be separated by irradiation with UV. The method for manufacturing a mask support template according to claim 9, wherein the temporary bonding part is liquid wax. The method for manufacturing a mask support template according to claim 7, wherein, if the process temperature is lowered in step (a), the shrinkage of the template will be smaller than the shrinkage of the mask, so that the mask is stretched in the lateral direction. Extension. A method for manufacturing a mask support template, the template being used to support a mask for forming an OLED pixel and corresponding the mask to a frame, the method comprising: (a) The step of preparing a template with a temporary bonding part formed on one side; (b) The step of raising the process temperature to at least higher than normal temperature, and bonding the mask with the mask pattern formed on the template; and (c) Steps to lower the process temperature, The thermal expansion coefficient of the template is lower than that of the mask. A method for manufacturing a frame-integrated mask. The frame-integrated mask is integrally formed by at least one mask and a frame for supporting the mask. The method includes: (a) The step of preparing a template with a temporary bonding part formed on one side; (b) The step of raising the process temperature to at least higher than normal temperature and bonding the mask metal film to the template; and (c) Steps to lower the process temperature; (d) A step of manufacturing a mask by forming a mask pattern on the mask metal film; (e) the step of loading the template on the frame having at least one mask unit area, and corresponding the mask to the mask unit area of the frame; and (f) The step of attaching the mask to the frame, The thermal expansion coefficient of the template is lower than that of the mask. A method for manufacturing a frame-integrated mask. The frame-integrated mask is integrally formed by at least one mask and a frame for supporting the mask. The method includes: (a) A step of loading a template with a mask bonded on one side onto a frame having at least one mask unit area, and corresponding the mask to the mask unit area of the frame; and (b) The step of attaching the mask to the frame, The thermal expansion coefficient of the template is lower than that of the mask.

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