TWI825149B - Producing method of mask integrated frame and frame - Google Patents

Abstract

The present invention relates to a method for manufacturing a frame-integrated mask. [Solution] The present invention relates to a method for manufacturing a frame-integrated mask, which integrates at least one mask with a frame for supporting the mask, wherein the method includes the following steps: (a) providing at least one mask with (b) providing the mask; (c) aligning the mask with the mask unit area of the frame; and (d) irradiating the laser to the welded portion of the mask to bond the mask to the frame, A plurality of adsorption holes are formed at a predetermined distance from the corner of the frame where the mask unit area is provided. In step (c), adsorption force is applied to the mask in contact with the frame through the plurality of adsorption holes, so that the The mask is tightly attached to the frame.

Description

Manufacturing method and frame of frame-integrated mask

The present invention relates to a manufacturing method and frame of a frame-integrated mask. More specifically, the mask can be supported and moved stably without deformation. When the mask is bonded to the frame, the adhesion between the mask and the frame can be improved, and the alignment between the masks can be improved ( align) precise frame-integrated mask manufacturing method and frame.

As a technology for forming pixels in the OLED manufacturing process, the FMM (Fine Metal Mask) method is mainly used. This method attaches a metal mask (Shadow Mask) in the form of a thin film to the substrate and deposits organic matter at the desired location.

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. During the process of fixing to the frame, each mask is stretched to make it flat. Adjusting the stretch to flatten an entire section of the mask is a very difficult task. In particular, in order to make all cells flat while aligning a mask pattern with a size of only a few μm to tens of μm, a high degree of work is required to fine-tune the tensile force applied to each side of the mask and confirm the alignment status in real time. Require.

Nonetheless, in fixing multiple masks to a frame, there is still the problem of poor alignment between masks and between mask units. In addition, during 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. Therefore, there are problems such as the mask sagging or twisting due to the load, and wrinkles and burrs caused by the welded parts during the welding process. (burr) and other problems that cause the alignment of the mask unit to shift.

Among ultra-high definition OLEDs, the existing QHD (Quarter High Definition) picture quality is 500-600PPI (pixel per inch), and the pixel size reaches about 30-50 μm, while 4K UHD (Ultra High Definition) and 8K UHD have higher than The higher resolution is ~860PPI, ~1600PPI, etc. In this way, considering the pixel size of ultra-high-definition OLED, the alignment error between each unit needs to be reduced to a few μm. Exceeding this error will lead to product defects, so the yield may be extremely low. Therefore, there is a need to develop technology that can prevent deformation such as sagging or twisting of the mask and achieve accurate alignment, as well as technology that can fix the mask to the frame, and the like.

The problem to be solved by the invention Therefore, the present invention is proposed to solve the above-mentioned problems in the prior art. When the mask is bonded to the frame, it is possible to prevent the mask from deforming and improve the adhesion between the mask and the frame. The manufacture of a frame-integrated mask Methods and frameworks.

Another 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.

Furthermore, an object of the present invention is to provide a method and frame for manufacturing a frame-integrated mask that prevents deformation such as sagging or twisting of the mask and enables accurate alignment.

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

Ways to solve problems The above object of the present invention is achieved by a method for manufacturing a frame-integrated mask, which integrates at least one mask with a frame for supporting the mask, wherein the method includes the following steps: (a) providing at least one a frame that masks the unit area; (b) providing the mask; (c) aligning the mask with the mask unit area of the frame; and (d) irradiating a laser to the welded portion of the mask to bond the mask to the frame , a plurality of adsorption holes are formed at a predetermined distance from the corner of the frame where the mask unit area is provided. In step (c), an adsorption force is applied to the mask in contact with the frame through the plurality of adsorption holes, so that the The mask is tightly attached to the frame.

Step (b) may include the following steps: (b1) electroforming a mask metal film on at least one side of the conductive substrate; (b2) separating the mask metal film from the conductive substrate; (b3) Bond the mask metal film to a template with a temporary adhesive portion formed on one side; and (b4) form a mask pattern on the mask metal film to manufacture a mask.

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

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

In step (c), the lower support body may be arranged at the lower part of the frame, and the lower support body includes an adsorption part for generating suction pressure.

The lower support can press the opposite side of the mask unit area for loading the mask.

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

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

Between step (b1) and step (b2), a step of reducing the thickness of the mask metal film adhered to the template is also included. The thickness of the mask metal film can be reduced by CMP (Chemical Mechanical Polishing), chemical wet etching (chemical wet etching) Perform any one of wet etching and dry etching.

The temporary adhesive part may be an adhesive or an adhesive sheet that is detachable by heating, or an adhesive or an adhesive sheet that is detachable by UV irradiation.

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

The template may include wafer, glass, silica, heat-resistant glass, quartz, aluminum oxide (Al ₂ O ₃ ), borosilicate glass, zirconia ) any material.

The laser irradiated from the upper part of the template passes through the laser through hole and can be irradiated onto the welding portion of the mask.

It may also include a step of heating, chemically treating, or applying ultrasonic waves to the temporarily bonded portion after step (d) to separate the mask and the template.

The frame may include an edge frame part and a mask unit sheet part, and the mask unit sheet part may include an edge sheet part; at least one first grid sheet part extending along the first direction and having both ends connected to the edge. sheet part; and at least one second grid sheet part, which extends along a second direction perpendicular to the first direction and intersects the first grid sheet part, and has both ends connected to the edge sheet part.

The mask and frame can be made of any material including invar, super invar, nickel, or nickel-cobalt.

In addition, the above object of the present invention is achieved by a frame used in a frame-integrated cover formed by a plurality of covers and a frame for supporting the cover, wherein the frame includes: an edge frame portion, It includes a hollow area; a mask unit sheet portion, which has a plurality of mask unit areas along at least one of a first direction and a second direction perpendicular to the first direction, and is connected to the edge frame portion; the mask unit sheet A plurality of adsorption holes are formed on the material part.

A plurality of adsorption holes are formed at a predetermined distance from the corner of the frame where the mask unit area is provided. The adsorption holes may be formed in a portion that does not overlap with the welded portion of the mask.

The lower part of the frame may also be provided with an adsorption part for generating suction pressure.

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

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

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

Furthermore, according to the present invention, it is possible to prevent the mask from deforming such as sagging or twisting, and to accurately align the mask.

Furthermore, according to the present invention, the production time can be significantly shortened and the productivity can be significantly increased.

The following detailed description of the invention will be described with reference to the accompanying drawings, which illustrate by way of example specific embodiments in which the invention can be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that the various embodiments of the invention, while different from each other, are not mutually exclusive. For example, the specific shapes, structures, and characteristics described here relate to one embodiment, and can be implemented in other embodiments without departing from the spirit and scope of the invention. In addition, it should be understood that the positions or arrangements of individual components in each disclosed embodiment can be changed without departing from the spirit and scope of the present invention. Therefore, the following detailed description should not be regarded as limiting, and as long as it is properly stated, the scope of the present invention is limited only by the appended claims and all equivalents thereto. Similar symbols in the drawings represent the same or similar functions in many aspects. For convenience, the length, area, thickness and shape can be exaggerated.

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

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

Referring to FIG. 1 , the existing mask 10 can be manufactured in a stick-type or a plate-type. The mask 10 shown in (a) of FIG. 1 is a strip mask, and can be used by welding and fixing both sides of the strip to the OLED pixel deposition frame. The mask 100 shown in (b) of FIG. 1 is a plate-type mask and can be used in a large-area pixel formation process.

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

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

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

Referring to (b) of Figure 2, fine-tune the tensile forces F1~F2 applied to each side of the strip mask 10, and after aligning at the same time, along with welding a part of the side of the strip mask 10, the strip mask 10 is 10 and frame 20 are connected to each other. (c) of FIG. 2 shows a side section of the strip mask 10 and the frame connected to each other.

Referring to Figure 3, 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 is shown. For example, the distances D1 to D1'' and D2 to D2'' between the patterns P of the cells C1 to C3 are different from each other, or the patterns P are skewed. Since the strip mask 10 has a large area including a plurality (for example, 6 units) of cells C1 to C6 and has a very thin thickness of several dozen μm, it is easy to sag or twist due to load. In addition, it is a very difficult task to adjust the tensile forces F1 to F2 so that all the units C1 to C6 become flat, and at the same time to confirm the alignment status of the units C1 to C6 through a microscope.

Therefore, slight errors in the tensile force F1~F2 may cause errors in the degree of stretching or expansion of each unit C1~C3 of the strip mask 10, thereby causing the distance D1~D1'', D2~D2'' are different. Although it is very difficult to align perfectly 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 impact on the pixel process of ultra-high-definition OLED, the alignment error is preferably no more than 3 μm. The alignment error between such adjacent units is called pixel position accuracy (PPA).

In addition, approximately 6-20 strip masks 10 are connected to one frame 20 respectively, and at the same time, the alignment between the multiple strip masks 10 and the multiple units C-C6 of the strip mask 10 is achieved. State accuracy is a very difficult task and only increases the process time based on alignment, which is an important reason for lowering productivity.

On the other hand, after the strip mask 10 is connected and fixed to the frame 20 , the tensile forces F1 to F2 applied to the strip mask 10 can act on the frame 20 in the opposite direction. That is, after the strip mask 10 tautly stretched by the tensile forces F1 to F2 is connected to the frame 20 , tension can be applied to the frame 20 . Normally, this tension is not large and does not have a large impact on the frame 20 . However, when the size of the frame 20 is reduced and its rigidity becomes low, this tension may slightly deform the frame 20 . In this way, a problem may occur in which the alignment state between the plurality of units C to C6 is destroyed.

In view of this, the present invention proposes a frame 200 and a frame-integrated mask that enable the mask 100 and the frame 200 to form an integrated structure. The mask 100 integrated with the frame 200 not only prevents deformation such as sagging or twisting, but also can be accurately aligned with the frame 200 . When the mask 100 is connected to the frame 200, no tensile force is applied to the mask 100. Therefore, after the mask 100 is connected to the frame 200, no tension causing deformation may be applied to the mask 200. Furthermore, the present invention has the advantage of being able to significantly shorten the manufacturing time for integrally connecting the mask 100 to the frame 200 and significantly improve the productivity.

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

Referring to FIGS. 4 and 5 , the frame-integrated mask may include multiple masks 100 and one frame 200 . In other words, the plurality of masks 100 are respectively bonded to the frame 200 . In the following, for convenience of explanation, the quadrangular mask 100 will be described as an example. However, before the mask 100 is bonded to the frame 200, it may be a strip mask shape with protrusions for clamping on both sides. After 100 is bonded to the frame 200, the protrusions can be removed.

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

To form a thinner thickness, the mask 100 may be formed by electroforming. Alternatively, the mask 100 may use a sheet produced by rolling. The mask 100 may be an invar material with a thermal expansion coefficient of approximately 1.0×10 ^-6 /°C or a super invar material with a thermal expansion coefficient of approximately 1.0×10 ^-7 /°C. Since the thermal expansion coefficient of the mask 100 of this material is very low, the pattern shape of the mask is less likely to be deformed by thermal energy. In the manufacture of high-resolution OLEDs, it can be used as FMM (Fine Metal Mask), shadow mask ( Shadow Mask). In addition, considering the recent development of technology for implementing a pixel deposition process within a range of small temperature changes, the mask 100 may also be made of materials such as nickel (Ni) or nickel-cobalt (Ni-Co) with a slightly larger thermal expansion coefficient. .

If a rolled film is used, it has the problem that the thickness is greater than that of a coating formed by electroforming. However, due to the low coefficient of thermal expansion CTE, it has the advantage of not requiring additional heat treatment processes and having strong corrosion resistance.

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

The frame 200 may include an edge frame portion 210 that is generally in a quadrangular shape or a square frame shape. The inside of the edge frame part 210 may have a hollow shape. That is, the edge frame part 210 may include the hollow region R. The frame 200 can be formed of constant steel, super constant steel, aluminum, titanium and other metal materials. Considering thermal deformation, it is preferably made of constant steel, super constant steel, nickel, nickel-cobalt which has the same thermal expansion coefficient as the mask. It is formed of other materials, and these materials can be applied to all edge frame parts 210 and mask unit sheet parts 220 that are components of the frame 200 .

In addition, the frame 200 is provided with a plurality of mask unit areas 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 can be formed by electroforming, rolling, or other film forming processes. In addition, the mask unit sheet portion 220 can be connected to the edge frame portion 210 after forming a plurality of mask unit regions CR on a planar sheet through laser scribing, etching, or the like. Alternatively, the mask unit sheet part 220 may connect a planar sheet to the edge frame part 210 and then form a plurality of mask unit regions CR through laser scribing, etching, or the like. This description will mainly describe a 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 .

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

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 .

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

In addition, further, the second grid sheet part 225 may be formed to extend along the second direction (vertical direction). The second grid sheet part 225 may be formed in a straight line, and both ends thereof may be connected to the edge sheet part 221 . The first grid sheet part 223 and the second grid sheet part 225 may perpendicularly cross each other. 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.

On the other hand, the spacing between the first grid sheet parts 223 and the spacing between the second grid sheet parts 225 may be the same or different according to the size of the mask unit C.

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

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

As for the mask unit sheet part 220, it is actually difficult to manufacture a thick sheet. If it is too thick, the organic source 600 (see FIG. 20) may block the path through the mask 100 during the OLED pixel deposition process. On the contrary, if it is too thin, it may be difficult to ensure sufficient rigidity to support the mask 100 . 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 may be approximately 0.1 mm to 1 mm. In addition, the width of the first grid sheet part 223 and the second grid sheet part 225 may be approximately 1 to 5 mm.

In the planar sheet, in addition to the areas occupied by the edge sheet part 221, the first grid sheet part 223, and the second grid sheet part 225, a plurality of mask unit areas CR (CR11~CR56) can be provided . From another perspective, the mask unit area CR may refer to all parts of the hollow area R of the edge frame part 210 except the edge sheet part 221 , the first grid sheet part 223 , and the second grid sheet part 225 The empty space outside the occupied area.

As the cell C of the mask 100 corresponds to the mask cell region CR, it can essentially serve as a channel for depositing the pixels of the OLED through the mask pattern P. As mentioned above, one mask unit C corresponds to one display of a smartphone or the like. A plurality of mask patterns P constituting one unit C may be formed in one mask 100 . Alternatively, one mask 100 may be provided with multiple units C, and each unit C may correspond to each unit area CR of the frame 200. However, in order to accurately align the mask 100, it is necessary to avoid a large area of the mask 100, and it is preferable to have one unit. C's small area mask 100. Alternatively, one mask 100 having a plurality of cells C may correspond to one unit region CR of the mask 200 . At this time, for accurate alignment, a corresponding mask 100 having 2-3 units C may be considered.

The mask 200 has a plurality of mask unit areas CR, and each mask 100 can be bonded so that each mask unit C corresponds to each mask unit area CR. Each mask 100 may include a mask unit C in which a plurality of mask patterns P are formed and a dummy portion around the mask unit C (corresponding to the portion of the mask film 110 excluding the unit C). The dummy part may include only the mask film 110, or may include the mask film 110 in which a predetermined dummy pattern having a similar form to the mask pattern P is formed. The mask unit C corresponds to the mask unit area CR of the frame 200, and part or all of the dummy part may be adhered to the frame 200 (mask unit sheet part 220). Thus, the mask 100 and the frame 200 can form an integrated structure.

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 can be directly formed with the edge frame using the hollow region R portion of the edge frame portion 210 The part 210 becomes a frame of an integrated grid frame (corresponding to the grid sheet parts 223 and 225). The frame of this form also includes at least one mask unit region CR, and the mask 100 can be made to correspond to the mask unit region CR to produce a frame-integrated mask.

The manufacturing process of the frame-integrated mask is explained below.

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

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

Next, referring to (b) of FIG. 6 , the mask unit sheet portion 220 is manufactured. The mask unit sheet part 220 can be manufactured by using electroforming, rolling or other film forming processes to produce a planar sheet, and then removing the mask unit region CR part by laser scribing, etching, or the like. In this specification, the formation of a 6×5 mask unit area CR (CR11~CR56) is taken as an example for explanation. There may be five first grid sheet parts 223 and four second grid sheet parts 225 .

Then, the mask unit sheet portion 220 can be made to correspond to the edge frame portion 210 . In the corresponding process, all sides of the mask unit sheet portion 220 of F1 to F4 can be stretched to make the mask unit sheet portion 220 flat and stretched, so that the edge sheet portion 221 and the edge frame portion 210 correspond. The mask unit sheet portion 220 can also be stretched by sandwiching the mask unit sheet portion 220 at a plurality of points (as an example in FIG. 6(b) , points 1 to 3) on one side. On the other hand, the mask unit sheet portions 220 F1 and F2 may be stretched along some of the side portions instead of all the side portions.

Then, when making the mask unit sheet part 220 correspond to the edge frame part 210, the edge sheet part 221 of the mask unit sheet part 220 can be bonded by welding W. Preferably, all sides of W are welded so that the mask unit sheet part 220 is firmly adhered to the edge frame part 210. The welding W should be performed as close as possible to the corner side of the frame part 210 in order to minimize the warp space between the edge frame part 210 and the mask unit sheet part 220 and improve the adhesion. The welded W part can be generated in a line or spot shape, has the same material as the mask unit sheet portion 220 , and can be integrated to connect the edge frame portion 210 and the mask unit sheet portion 220 medium.

7 is a schematic diagram showing a manufacturing process of a frame according to another embodiment of the present invention. In the embodiment of FIG. 6 , the mask unit sheet portion 220 having the mask unit region CR is first manufactured and then bonded to the edge frame portion 210 . In the embodiment of FIG. 7 , a planar sheet is bonded to the edge frame portion 210 to form the mask unit sheet portion 220 . Mask the CR part of the unit area.

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

Then, referring to FIG. 7(a) , a planar sheet (planar mask unit sheet portion 220') can be made to correspond to the edge frame portion 210. The mask unit sheet portion 220' is in a planar state in which the mask unit region CR has not yet been formed. During the corresponding process, all side portions of the F1 to F4 mask unit sheet portions 220' can be stretched to make the mask unit sheet portion 220' in a flat and stretched state to correspond to the edge frame portion 210. The unit sheet portion 220' can also be stretched by sandwiching the unit sheet portion 220' at a plurality of points (as an example in FIG. 7(a), points 1 to 3) on one side. On the other hand, the mask unit sheet portions 220' of F1 and F2 may be stretched along some of the side portions instead of all the side portions.

Then, when the mask unit sheet portion 220' is made to correspond to the edge frame portion 210, the edge portion of the mask unit sheet portion 220' can be bonded by welding W. Preferably, all sides of W are welded so that the mask unit sheet portion 220' is firmly adhered to the edge frame portion 220. The welding W should be performed as close as possible to the corner side of the edge frame part 210 to minimize the warp space between the edge frame part 210 and the mask unit sheet part 220' and improve the adhesion. The welded W part can be generated in the shape of a line or a spot, has the same material as the mask unit sheet part 220', and can connect the edge frame part 210 and the mask unit sheet part 220' into one body. medium.

Then, referring to FIG. 7(b) , the mask unit region CR is formed on the planar sheet (the planar mask unit sheet portion 220'). The mask unit region CR can be formed by removing the sheet of the mask unit region CR through laser scribing, etching, or the like. In this specification, the formation of a 6×5 mask unit area CR (CR11~CR56) is taken as an example for explanation. When the mask unit region CR is formed, the portion welded W to the edge frame portion 210 becomes the edge sheet portion 221, and the mask unit sheet portion 220 provided with five first grids can be formed. grid sheet part 223 and four second grid sheet parts 225.

FIG. 8 is a schematic diagram showing a conventional mask used to form a high-resolution OLED.

In order to realize high-resolution OLEDs, the size of patterns is gradually becoming smaller, and therefore the thickness of the mask metal film used must also be thinned. As shown in (a) of Fig. 8, in order to realize high-resolution OLED pixels 6, the pixel pitch and pixel size on the mask 10' are reduced (PD->PD'). Furthermore, in order to prevent uneven deposition of the OLED pixels 6 due to shadow effects, it is necessary to form the pattern 14 of the mask 10' obliquely. However, in the process of forming the pattern 14 obliquely on the thick mask 10' having a thickness T1 of about 30 to 50㎛, it is difficult to perform the patterning 13 matching the fine pixel pitch PD' and the pixel size, so it will become Reasons for poor productivity in processing technology. In other words, in order to form the pattern 14 obliquely while having a fine pixel pitch PD', it is necessary to use a thinner mask 10'.

In particular, in order to achieve UHD-level high resolution, as shown in FIG. 8(b) , fine patterning can be performed only by using a thin mask 10' with a thickness T2 of approximately 20㎛ or less. Furthermore, in order to achieve ultra-high resolution above UHD, it may be considered to use a thin mask 10' having a thickness T2 of about 10㎛.

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

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

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

In achieving ultra-high image quality pixels above the UHD level, uneven coating and coating patterns (mask patterns P) may have a negative impact on the formation of pixels. For example, the current QHD image quality is 500~600 PPI (pixel per inch), and the pixel size reaches about 30~50㎛. The 4K UHD and 8K UHD high image quality have higher than the former ~860 PPI and ~1600 PPI. etc. resolution. Microdisplays that are directly applicable to VR machines or used when inserted into VR machines aim at ultra-high image quality of about 2000 PPI or above, and the pixel size is about 5~10㎛. The pattern width of the FMM and shadow mask applied thereto can be formed in a size of several μm to tens of μm, preferably less than 30 μm. Therefore, defects of several μm size also occupy a large proportion in the pattern size of the mask. In addition, in order to remove defects in the cathode made of the above-mentioned materials, additional processes for removing metal oxides, impurities, etc. may be performed. This process may cause other defects such as etching of the cathode material.

Therefore, the present invention can use a mother plate (or cathode) of single crystal material. In particular, single crystal silicon material is preferred. The motherboard of single crystal silicon material can be doped at a high concentration of more than 10 ¹⁹ /cm ³ to make it conductive. Doping can be done on the entire motherboard or only on the surface portion of the motherboard.

In addition, 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; including CH ₃ Single crystal ceramics for superconductors such as NH ₃ PbCl ₃ , CH ₃ NH ₃ PbBr ₃ , CH ₃ NH ₃ PbI ₃ , SrTiO ₃ and other perovskite structures; single crystal super heat-resistant alloys for aircraft parts. Metal and carbon materials are basically conductive materials. In the case of semiconductor materials, in order to achieve conductivity, high concentration doping of 10 ¹⁹ /cm ³ or more can be performed. Other materials can be conductive by performing doping or forming oxygen vacancy. Doping can be performed on the entire motherboard or only on the surface portion of the motherboard.

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

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

Referring again to FIG. 9(a) , the conductive base material 21 is used as a motherboard (cathode body), and the anodes (not shown) are arranged at intervals, so that the conductive base material 21 can be A metal film 110 [or plating film 110] is formed on the top by electroforming. The mask metal film 110 may be formed on the exposed upper surface and side surfaces of the conductive substrate 21 , which is disposed opposite to the anode and on which an electric field can act. The metal film 110 may be formed not only on the side surfaces of the conductive base material 21 but also on a part of the lower surface of the conductive base material 21 .

Then, use a laser to cut the edge portion of the D mask metal film 110 or form a photoresist layer on top of the mask metal film 110, and only etch and remove the portion of the D mask metal film 110 exposed. Thereby, as shown in FIG. 9( b ), the mask metal film 110 can be separated from the conductive base material 21 .

In addition, before separating the mask metal film 110 from the conductive base material 21, heat treatment H may be performed. A feature of the present invention is to separate the mask metal film from the conductive base material 21 [or motherboard, cathode] in order to reduce the thermal expansion coefficient of the mask 100 and prevent thermal deformation of the mask 100 and the mask pattern P. Heat treatment H before 110. Heat treatment can be carried out at temperatures from 300°C to 800°C.

In general, the thermal expansion coefficient of constant steel sheets produced by electroforming is higher than that of constant steel sheets produced by rolling. Therefore, the thermal expansion coefficient can be reduced by heat treating the Hengfan steel sheet, but during the heat treatment process, the Hengfan steel sheet will peel, deform, etc. This is a phenomenon caused by heat treatment of only the constant steel thin plate or heat treatment of the constant steel thin plate temporarily bonded only on the upper surface of the conductive base material 21 . However, in the present invention, the mask metal film 110 is formed not only on the upper surface of the conductive base material 21 but also on part of the side surfaces and the lower surface, so 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 base material 21 and the mask metal film 110 are closely adhered, there is an advantage that peeling, deformation, etc. caused by the heat treatment can be prevented and the heat treatment can be performed stably.

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

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

Referring to FIG. 10(a) , a metal sheet generated based on a rolling process can be used as the mask metal film 110'. The metal sheet produced based on the rolling process can have a thickness of tens to hundreds of millimeters in terms of manufacturing process. As mentioned above in Figure 8, in order to achieve high resolution at the UHD level, only a thin mask metal film 110 with a thickness of about 20㎛ or less can be used for fine patterning. In order to achieve ultra-high resolution above UHD, High resolution requires the use of a thinner mask metal film 110 with a thickness of about 10㎛. However, the mask metal film 110' produced by the rolling process has a thickness of about 25 to 500㎛, so it is necessary to make the thickness thinner.

Therefore, a process of planarizing PS on one side of the mask metal film 110' may also be performed. Here, the planarization PS means mirroring one surface (upper surface) of the mask metal film 110' and removing a part of the upper part of the mask metal film 110' to reduce the thickness. Planarization PS can be performed by the CMP (Chemical Mechanical Polishing) method, and any known CMP method can be used without special restrictions. Moreover, the thickness of the mask metal film 110' can be reduced by chemical wet etching or dry etching. In addition to this, other planarization processes that can thin the thickness of the mask metal film 110' may also be used, and are not particularly limited.

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

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

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

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

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

The template 50 is preferably made of a transparent material to facilitate vision during the process of aligning and bonding the mask 100 with the frame 200 . Moreover, if it is a transparent material, the laser can also penetrate it. As a transparent material, glass, silica, heat-resistant glass, quartz, aluminum oxide (Al ₂ O ₃ ), borosilicate glass, zirconia, etc. can be used. Material. As an example, the template 50 can use BOROFLOAT ^® 33 material among borosilicate glass which has excellent heat resistance, chemical durability, mechanical strength, transparency, etc. Furthermore, the thermal expansion coefficient of BOROFLOAT ^® 33 is about 3.3, which is less different from the thermal expansion coefficient of the Hengfan steel mask metal film 110, and has the advantage of easy control of the mask metal film 110.

In addition, the surface of the template 50 that is in contact with the mask metal film 110 may be a mirror surface so that no air gap is generated at the interface with the mask metal film 110 [or the mask 100 ]. Based on this, the surface roughness Ra of one side of the template 50 may be 100 nm or less. In order to realize the template 50 having a surface roughness Ra of 100 nm or less, a wafer may be used for the template 50 . The surface roughness Ra of the wafer is about 10 nm, and there are many products on the market, and the surface treatment process is well known, so it can be used as the template 50 . The surface roughness Ra of the template 50 is at the nm level, so there is no gap AG or almost no gap AG, and welding beads WB are easily generated by laser welding, so the alignment error of the mask pattern P is not affected.

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

The laser through holes 51 do not necessarily correspond to the position and number of the welding parts. For example, only a part of the laser through hole 51 may be irradiated with the laser L to perform welding. In addition, a part of the laser through holes 51 that does not correspond to the welding part may be used instead of the 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 hole 51 does not need to be formed.

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

The temporary adhesive part 55 may use an adhesive or adhesive sheet that is detachable by heating, or an adhesive or adhesive sheet that is detachable by UV irradiation.

As an example, liquid wax can be used for the temporary bonding portion 55 . The liquid wax may be the same wax used in the semiconductor wafer polishing step and the like, and the type thereof is not particularly limited. Liquid wax mainly contains substances such as acrylic acid, vinyl acetate, nylon, various polymers and solvents, which are resin components used to control adhesion and impact resistance related to maintenance. As an example, the temporary adhesive portion 55 can use acrylonitrile butadiene rubber (ABR) as a resin component and SKYLIQUID ABR-4016 containing n-propanol as a solvent component. The liquid wax can be formed on the temporary adhesive portion 55 using spin coating.

As a liquid wax, the temporary adhesive part 55 becomes less viscous at temperatures higher than 85°C to 100°C, and becomes more viscous at temperatures lower than 85°C, with part of it hardening like a solid, and can make the mask The cover metal film 110 is fixed and bonded to the template 50 .

Then, referring to (b) of FIG. 11 , the mask metal film 110' can be bonded to the template 50. After the liquid wax is heated to above 85°C and the mask metal film 110' contacts the template 50, the mask metal film 110' and the template 50 are passed between rollers for bonding.

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

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

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

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

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

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

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

Next, the mask metal film 110 may be etched. Dry etching, wet etching, or other methods may be used, and the method is not particularly limited. As a result of the etching, the portion of the mask metal film 110 exposed in the vacant positions 26 between the insulating portions 25 is etched. The etched portion of the mask metal film 110 forms the mask pattern P, whereby the mask 100 formed with a plurality of mask patterns P can be manufactured.

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

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

Since the frame 200 has multiple mask unit areas CR (CR11~CR56), multiple mask units C (C11~56) corresponding to each mask unit area CR (CR11~CR56) can also be formed. Cover 100. Furthermore, a plurality of templates 50 each supporting a plurality of masks 100 may be provided.

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

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

15 is a schematic diagram illustrating a state in which a template is mounted on a frame so that a mask corresponds to a unit area of the frame according to an embodiment of the present invention. FIG. 16 is a schematic diagram illustrating a state in which the adsorption force VS is applied to the mask through the adsorption holes 229 according to an embodiment of the present invention. FIG. 17 is a partial schematic diagram showing a frame 200 in which a plurality of adsorption holes 229 are formed according to an embodiment of the present invention. Although FIG. 15 shows an example in which one mask 100 is associated with/glued to the unit area CR, multiple masks 100 may also be associated with all unit areas CR at the same time so that the masks 100 are adhered to the frame 200 . Process. At this time, there may be a plurality of templates 50 for supporting a plurality of masks 100 respectively. In addition, although FIG. 16 shows the form in which the adsorption holes 229 are formed on the first grid sheet part 223 to apply the adsorption force VS, it is of course also possible to form the adsorption holes 229 on the edge sheet part 221 and on the edge sheet. A predetermined step is formed between the edge portion 221 and the edge frame portion 210 , thereby applying an adsorption force VS to the adsorption holes 229 of the edge sheet portion 221 .

Then, referring to FIG. 15 , the mask 100 can be made to correspond to one mask unit area CR of the frame 200 . Correspondence between the mask 100 and the mask unit area CR can be achieved by loading the template 50 on the frame 200 [or the mask unit sheet part 220]. While controlling the position of the template 50/vacuum suction cup 90, 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 and the frame 200 can be tightly abutted.

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

Referring to FIGS. 15 to 17 , a plurality of adsorption holes 229 may be formed near the corners of the frame 200 having the mask unit region CR. Specifically, a plurality of adsorption holes 229 may be formed at a predetermined distance from the corners of the mask unit sheet part 220 , and more specifically, may be formed at a predetermined distance from the inner corners of the edge sheet part 221 . part and the corners of the first and second grid sheet parts 223 and 225 that are separated by a predetermined distance.

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

As shown in FIG. 16 , when the template 50 is mounted on the frame 200 [or the mask unit sheet part 220 ], a part of the lower surface of the mask 100 is in contact with the upper part of the frame 200 [or the mask unit sheet part 220 ]. Abut. The upper part of the adsorption hole 229 formed in the frame 200 [or the mask unit sheet part 220] corresponds to the lower surface of the mask 100, and the adsorption force (suction pressure) applying means corresponding to the lower part of the adsorption hole 229 passes through the adsorption hole. 229 applies the adsorption force VS [or suction pressure VS] to the mask 100 to pull the portion of the mask 100 corresponding to the adsorption hole 229 . Thereby, the mask 100 will be more closely connected with the frame 200, so when laser welding is performed, the welding beads WB can be generated more stably.

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

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

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

The lower support body 70 may 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 in the upper direction, 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 70 and the template 50 press the edges of the mask 100 and the frame 200 [or the mask unit sheet part 220] in opposite directions, so the alignment of the mask 100 will not be destroyed and the It remains aligned.

Furthermore, the adsorption force VS [or suction pressure VS] is provided from the adsorption part 75 of the lower support 70 , and as the adsorption force VS is applied to the mask 100 through the adsorption hole 229 , the mask 100 will be pulled to the adsorption position. Part 75 side (lower side). In this way, the interface between the mask 100 and the frame 200 [or the mask unit sheet part 220] will be in close contact.

Since the suction part 75 strongly pulls the mask 100, there is no slight gap between the interface of the mask 100 and the frame 200. As a result, since the mask 100 and the frame 200 [in the enlarged view of FIG. 16 , the first grid sheet portion 223] are in close contact, even if the laser L is irradiated at any position of the welding portion, the gap between the mask 100 and the frame 200 It is also easy to generate welding beads WB. The welding beads WB connect the mask 100 and the frame 200 into one body, and as a result, there is an advantage that the welding can be performed stably.

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

After the adsorption force VS of the adsorption part 75 is applied, the laser L is irradiated onto the mask 100 so that the mask 100 is bonded to the frame 200 through laser welding. The welding portion of the laser welded mask generates welding beads WB, which may have the same material as the mask 100/frame 200 and be integrated with the mask 100/frame 200.

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

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

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

As an example, a solvent debonding method based on chemically treated CM can be used. The temporary adhesive portion 55 is dissolved by penetration of a solvent to achieve peeling. 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 . Solvent stripping can be performed at room temperature and does not require other complex stripping equipment, so it is more economical than other stripping methods.

As another example, a heat debonding method based on heating ET can be used. High-temperature heat induces decomposition of the temporary adhesive portion 55, and if the adhesive force between the mask 100 and the template 50 becomes smaller, the mask 100 and the template 50 can be peeled off in the vertical or left-right direction.

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

As another example, a room temperature debonding method based on chemical treatment CM, application of ultrasonic waves US, application of UVUV, etc. can be used. If a part (center part) of the mask 100 or the template 50 is non-sticky, only the edge part is adhered by the temporary adhesive part 55 . In addition, since solvent penetrates into the edge portion during peeling, peeling can be achieved by dissolving the temporary adhesive portion 55 . This method has the following advantages: during the bonding and peeling process, the remaining parts except the edge areas of the mask 100 and the template 50 will not be directly damaged or defects caused by adhesive material residue during peeling will not occur. Moreover, this method is different from the thermal stripping method in that it does not require a high-temperature heat treatment process during stripping, so it has the advantage of relatively reducing process costs.

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

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

Since the mask unit sheet portion 220 of the frame 200 has a thin thickness, when the mask 100 is adhered to the mask unit sheet portion 220 with a tensile force applied, the tensile force remaining in the mask 100 acts. The mask unit sheet portion 220 and the mask unit region CR may be deformed. Therefore, the mask 100 should be adhered to the mask unit sheet portion 220 without applying tensile force to the mask 100 . The present invention can complete the process of making the mask 100 correspond to the mask unit area CR of the frame 200 by only attaching the mask 100 to the template 50 and loading the template 50 on the frame 200. This process does not impose any force on the mask 100. Any stretching force. This can prevent the frame 200 (or the mask unit sheet portion 220 ) from deforming due to the tensile force applied to the mask 100 acting in reverse on the frame 200 as tension.

The existing mask 10 of FIG. 1 includes six units C1 to C6 and therefore has a longer length, while the mask 100 of the present invention includes one unit C and therefore has a shorter length, so the PPA (pixel position accuracy) is distorted. will become smaller. Assuming that the length of the mask 10 including multiple units C1 ~ C6, ... is 1 m, and a PPA error of 10 μm occurs in the total length of 1 m, the mask 100 of the present invention can be reduced with the relative length (equivalent to the unit C quantity decreases) so that the above error range is 1/n. For example, if the length of the mask 100 of the present invention is 100 mm, it has a length reduced from 1 m of the existing mask 10 to 1/10. Therefore, a PPA error of 1 μm occurs in the total length of 100 mm, significantly reducing the alignment error. .

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

As far as the present invention is concerned, since only one unit C of the mask 100 needs to be matched and the alignment status is confirmed, compared with the existing method of matching multiple units C (C1~C6) at the same time and needing to confirm all the alignment statuses , which can significantly shorten manufacturing time.

That is, the manufacturing method of the frame-integrated mask of the present invention can significantly shorten the time compared with the conventional method in which each unit C11 to C16 included in the six masks 100 is connected to one unit region CR11 to CR16 respectively. Corresponding to and confirming each alignment status 6 times, 6 units C1~C6 are matched at the same time, and the alignment status of 6 units C1~C6 needs to be confirmed at the same time.

In addition, in the manufacturing method of the frame-integrated mask of the present invention, the product yield in the process of making 30 masks 100 correspond to 30 unit areas CR (CR11~CR56) and align them 30 times will be significantly improved. This is higher than the yield of existing products in the process of making five masks 10 each including six units C1 to C6 (refer to (a) of FIG. 2 ) correspond to and align with the frame 20 five times. Since the existing method of aligning 6 units C1 to C6 in an area corresponding to 6 units C at a time is an obviously tedious and difficult operation, the product yield is low.

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

When each mask 100 is respectively adhered to its corresponding mask unit area CR and the template 50 is separated from the mask 100, the plurality of masks 100 exert tension to shrink in opposite directions, so the force is offset, so in The mask unit sheet portion 220 does not deform. For example, in the first grid sheet portion 223 between the mask 100 attached to the CR11 unit area and the mask 100 attached to the CR12 unit area, the mask 100 attached to the CR11 unit area acts in the right direction. The tension and the tension acting in the left direction of the mask 100 attached to the CR12 unit area cancel each other out. Thereby, the deformation of the frame 200 [or the mask unit sheet part 220 ] due to tension is minimized, so that the alignment error of the mask 100 [or the mask pattern P] can be minimized.

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

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

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 . The target substrate 900 may be provided with a frame-integrated mask 100 or 200 [or FMM] that allows the organic source 600 to be deposited in different pixels in a close or very close manner. The magnet 310 can generate a magnetic field and adhere to the target substrate 900 through the magnetic field.

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

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

At the first temperature higher than the pixel deposition process temperature, the mask 100 is adhesively fixed on the frame 200 . Therefore, even if the temperature is raised to the temperature used for the pixel deposition process, it will have almost no impact on the position of the mask pattern P. The PPA between the mask 100 and the adjacent mask 100 can be maintained at no more than 3 μm.

As mentioned above, the present invention has been illustrated and described by enumerating preferred embodiments, but is not limited to the above-described embodiments. A person skilled in the art can make various modifications and changes without departing from the spirit of the present invention. Such deformations and changes are within the scope of the present invention and the appended patent applications.

6:pixel 10: Strip mask 10’:mask 11:Mask film 13:Patterning 14: Pattern 20:Frame 21: Conductive substrate 26: Empty position 50:Template 50a:Center 50b: Edge 51:Laser through hole 55: Temporary bonding part 56:Basilar membrane 57a, 57b: Adhesion layer 58a, 58b: Separation membrane/release membrane 70:Lower support body 75:Adsorption part 76:Vacuum channel 90: Vacuum suction cup 100:mask 110: Masking film 110’: mask metal film 200:Frame 210: Edge frame part 220, 220’: Sheet part of mask unit 221: Edge sheet part 223: The first grid sheet department 225: Second grid sheet part 229: Adsorption hole 300:Magnetic board 310: There is a magnet 350: Cooling water pipe 500: Deposition source supply department 600:Organic source 700: pixels 900:Target substrate 1000:OLED pixel deposition device AG:gap C: unit, mask unit C1~C6: unit CM: chemical treatment CR(CR11~CR56): Mask unit area DM: Dummy part, mask dummy part D1~D1'', D2~D2'': distance D:Laser cutting ET: heating F1~F2: stretch H: Heat treatment L:Laser R: Hollow area of edge frame part Ra: surface roughness P: Mask pattern PS: Flatten PD: Reduce pixel pitch PD': pixel pitch VS: Apply adsorption force and suction pressure US: Apply ultrasonic waves UV: Apply UV W: welding WB: welding beads S: formed obliquely; tapered T1, T2: thickness

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

Figure 2 is a schematic diagram illustrating a conventional process of bonding a mask to a frame.

FIG. 3 is a schematic diagram illustrating the occurrence of alignment errors between units in a conventional stretching mask process.

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

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

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

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

FIG. 8 is a schematic diagram showing a conventional mask used to form a high-resolution OLED.

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

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

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

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

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

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

FIG. 16 is a schematic diagram illustrating a state in which adsorption force is applied to the mask through adsorption holes according to an embodiment of the present invention.

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

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

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

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

50:Template

51:Laser through hole

55: Temporary bonding part

70:Lower support body

75:Adsorption part

76:Vacuum channel

90:Target substrate

100:mask

223: The first grid sheet department

229: Adsorption hole

VS: Apply adsorption force and suction pressure

WB: welding beads

L:Laser

Claims (15)

A method of manufacturing a frame-integrated mask, which integrates at least one mask with a frame for supporting the mask, wherein the method includes the following steps: (a) providing a frame with at least one mask unit area; ( b) provide a mask; (c) make the mask correspond to the mask unit area of the frame; and (d) irradiate the laser to the welding portion of the mask so that the mask is bonded to the frame and corresponds to the area where the mask unit is provided A plurality of adsorption holes are formed on the corners of the frame at a predetermined distance apart. In step (c), adsorption force is applied to the mask in contact with the frame through the plurality of adsorption holes, so that the mask is in close contact with the frame. Step (b) includes the following steps: (b1) electroforming a mask metal film on at least one side of the conductive substrate; (b2) separating the mask metal film from the conductive substrate; (b3) Bond the mask metal film to a template with a temporary adhesive portion formed on one side; and (b4) form a mask pattern on the mask metal film to manufacture a mask. A method of manufacturing a frame-integrated mask, which integrates at least one mask with a frame used to support the mask, wherein the method includes the following steps: (a) providing a frame with at least one mask unit area; (b) providing a mask; (c) making the mask correspond to the mask unit area of the frame; and (d) irradiating the laser to the welded portion of the mask to The mask is bonded to the frame, and a plurality of adsorption holes are formed at a predetermined distance from the corner of the frame where the mask unit area is provided. In step (c), through the plurality of adsorption holes, the portion in contact with the frame is The mask applies adsorption force to make the mask closely adhere to the frame, wherein step (b) includes the following steps: (b1) providing a mask metal film, the mask metal is a film (sheet) manufactured by rolling (rolling) ; (b2) Bond the mask metal film to a template with a temporary adhesive portion formed on one side; (b3) Form a mask pattern on the mask metal film to manufacture a mask. The manufacturing method of a frame-integrated mask as described in claim 1 or 2, wherein step (c) is a step of loading the template on the frame and making the mask correspond to the mask unit area of the frame. The manufacturing method of a frame-integrated mask according to claim 1 or 2, wherein in step (c), a lower support body is arranged at the lower part of the frame, and the lower support body includes an adsorption part for generating suction pressure. The manufacturing method of the frame-integrated mask according to claim 4, wherein the lower support body Extrude the opposite side of the mask cell area used to load the mask. The method of manufacturing a frame-integrated mask according to claim 1 or 2, wherein the adsorption holes are formed in a portion that does not overlap with the welded portion of the mask. The manufacturing method of a frame-integrated mask as described in claim 1, wherein the conductive substrate is a wafer, and a process of heat-treating the mask metal film is further performed between steps (b1) and (b2). The manufacturing method of the frame-integrated mask as described in claim 2, wherein between step (b2) and step (b3), it also includes the step of reducing the thickness of the mask metal film adhered to the template, and the mask metal film The thickness reduction is performed by any one of CMP (Chemical Mechanical Polishing), chemical wet etching, and dry etching. The manufacturing method of a frame-integrated mask as described in claim 1 or 2, wherein the temporary adhesive part is based on an adhesive or adhesive sheet that is detachable by heating and an adhesive or adhesive sheet that is detachable by irradiating UV. The manufacturing method of a frame-integrated mask according to claim 1 or 2, wherein the step of forming a mask pattern on the mask metal film to manufacture the mask includes: (1) forming a patterned pattern on the mask metal film Insulation Department; (2) Etching the portion of the mask metal film exposed between the insulating portions to form a mask pattern; and (3) removing the insulating portions. The method for manufacturing a frame-integrated mask as described in claim 1 or 2, wherein the template includes wafer, glass, silica, heat-resistant glass, quartz, aluminum oxide (Al2O3 ), borosilicate glass, or zirconia. The manufacturing method of a frame-integrated mask as described in claim 3, wherein the laser irradiated from the upper part of the template passes through the laser through hole and is irradiated on the welding part of the mask. The manufacturing method of the frame-integrated mask as described in claim 3, which further includes the step of heating, chemically treating, or applying ultrasonic waves to the temporary bonding portion after step (d) to separate the mask and the template. . The manufacturing method of a frame-integrated mask according to claim 1 or 2, wherein the frame includes an edge frame part and a mask unit sheet part, and the mask unit sheet part includes an edge sheet part; at least one first grid a sheet portion extending along a first direction and having both ends connected to the edge sheet portion; and at least one second grid sheet portion extending along a second direction perpendicular to the first direction and connected to the first The grid sheet parts intersect, and both ends are connected to the edge sheet parts. The manufacturing method of the frame-integrated mask as described in claim 1 or 2, wherein the mask and The frame is made of any material including invar steel (invar), super invar steel (super invar), nickel, or nickel-cobalt.