TW202013064A - Producing method of mask integrated frame and mask for forming oled picture element - Google Patents

Abstract

The present invention relates to a method for manufacturing a frame-integrated mask, and to a mask for forming OLED pixels. The method for manufacturing a frame-integrated mask according to the present invention is a method for manufacturing a frame-integrated mask in which at least one mask and a frame supporting the mask are integrally formed, the method being characterized by comprising: (a) a step for providing the frame having at least one mask cell region; (b) a step for attaching the mask onto a tray; (c) a step for loading the tray onto the frame such that the mask corresponds to the mask cell region of the frame; and (d) a step for emitting laser beams onto weld portions of the mask so as to attach the mask to the frame, wherein the mask includes a mask cell, in which a plurality of mask patterns are formed, and a dummy around the mask cell, the plurality of weld portions are formed at intervals on at least a portion of the dummy, and wrinkle-preventing patterns are formed in the vicinity of each of the weld portions at a predetermined distance therefrom.

Description

Frame integrated mask manufacturing method and OLED pixel forming mask

Field of invention The invention relates to a manufacturing method of a frame-integrated mask and a mask for forming OLED pixels. More specifically, it relates to a frame-integrated type that integrates the mask with the frame and reduces the deformation of the mask when welding to improve position accuracy, thereby accurately aligning the masks. Manufacturing method of mask and mask for forming OLED pixels.

Background of the invention Recently, research on electroforming methods in the manufacture of thin plates is being conducted. The electroforming method is to impregnate the anode and cathode in the electrolyte, and apply power to make the metal thin plate electroplated on the surface of the cathode, so it is a method capable of manufacturing the electrode thin plate and expected to be mass-produced.

On the other hand, as a technology for forming pixels in the OLED manufacturing process, the FMM (Fine Metal Mask) method is mainly used, which closely fits a shadow mask in the form of a thin film to a substrate and is in a desired position Organic matter is deposited on it.

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

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

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

Summary of the invention Problems to be solved by invention

The present invention was developed to solve the problems of the aforementioned conventional technology, and its object is to provide a method for manufacturing a frame-integrated mask in which the mask and the frame can form an integrated structure.

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

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

In addition, an object of the present invention is to provide a mask for forming an OLED pixel that prevents deformation of the mask when the mask is adhered to the frame, and reduces deformation of the mask during welding, thereby improving position accuracy. Ways to solve the problem

The foregoing object of the present invention is achieved by a mask for forming an OLED pixel, which includes a mask unit formed with a plurality of mask patterns; and a dummy part located around the mask unit, at least a part of the dummy part is formed with a mutual spacing A plurality of welded portions formed on the ground are formed with anti-crease patterns around a predetermined distance from each welded portion.

The anti-wrinkle pattern is concentric with the welding part, and it can occupy at least an area on the circumference having a diameter larger than that of the welding part.

The anti-wrinkle pattern includes a plurality of unit anti-wrinkle patterns, and the unit anti-wrinkle pattern may be any shape of a circle or an ellipse.

The plurality of unit anti-crease patterns are concentric with the welded portion, and they may be arranged spaced apart from each other at least on a region on the circumference whose diameter is larger than that of the welded portion.

The anti-wrinkle pattern includes a plurality of unit anti-wrinkle patterns, the unit anti-wrinkle pattern is concentric with the welded portion, and its shape may include at least a part of the circumference having a diameter larger than the diameter of the welded portion.

The shape of a unit anti-crease pattern may be a closed pattern shape, which is concentric with at least a part of the circumference concentric with the specific welding portion and having a diameter greater than the diameter of the specific welding portion, and concentric with the welding portion adjacent to the specific welding portion And the diameter is larger than at least a part of the circumference of the adjacent welded portion.

An adjacent pair of unit anti-crease patterns may further include a closed pattern shape with sides facing and parallel to each other.

The anti-wrinkle pattern includes a plurality of unit anti-wrinkle patterns, and the shape of the unit anti-wrinkle pattern may be a closed pattern shape that connects at least a part of the circumference of the circumference that is concentric with the welding site and has a diameter greater than the first diameter of the welding part and has At least a portion of the circumference of the second diameter larger than the first diameter.

A plurality of unit anti-crease patterns may be arranged spaced apart from each other, thereby surrounding one welding part.

The anti-crease pattern and the mask pattern are formed spaced apart from each other, and may further include a plurality of buffer patterns having a width greater than that of the mask pattern.

The shape of the unit buffer pattern is any one of a circle and an ellipse.

Moreover, the aforementioned object of the present invention can be achieved by a method of manufacturing a frame-integrated mask in which at least one mask and a frame supporting the mask are formed as an integrated body, the method of manufacturing the frame-integrated mask includes: (a) providing The step of having a frame with at least one mask unit area; (b) the step of attaching the mask to the tray; (c) the step of loading the tray on the frame and covering the mask unit area corresponding to the frame, and (D) The step of irradiating laser to the welding part of the mask to make the mask adhere to the frame, the mask includes a mask unit formed with a plurality of mask patterns; and a virtual part located around the mask unit, at least a part of the virtual part A plurality of welded portions formed spaced apart from each other are formed thereon, and a wrinkle-preventing pattern is formed around each welded portion at a predetermined distance.

(B) The step may be a step of loading the tray on the frame after attaching the mask to the tray and corresponding to the mask unit area of the frame.

The anti-wrinkle pattern is concentric with the welded portion, and can occupy at least an area on the circumference whose diameter is larger than the diameter of the welded portion.

The anti-crease pattern and the mask pattern are formed spaced apart from each other, and may further include a plurality of buffer patterns having a width greater than that of the mask pattern. Invention effect

According to the present invention constructed as described above, the cover and the frame can form an integrated structure.

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

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

Moreover, according to the present invention, deformation of the mask is prevented when the mask is adhered to the frame, and deformation of the mask is reduced during welding, thereby improving position accuracy.

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

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

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

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

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

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

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

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

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

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

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

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

In view of this, the present invention proposes a frame 200 and a frame-integrated mask capable of forming the mask 100 and the frame 200 into an integrated structure. The cover 100 integrated with the frame 200 can prevent deformation such as sagging or twisting, and is accurately aligned with the frame 200. When the mask 100 is connected to the frame 200, no tensile force is applied to the mask 100, and therefore, after the mask 100 is connected to the frame 200, no tension may be applied to the mask 200 to cause deformation. Also, the manufacturing time for integrally connecting the mask 100 to the frame 200 can be significantly shortened, and the productivity can be significantly improved.

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

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

A plurality of mask patterns P are formed on each mask 100, and one unit C may be formed in one mask 100. One mask unit C may correspond to one display of a smartphone or the like. The mask 100 may be formed in an electroforming manner so as to be able to be formed in a thin thickness. The mask 100 may be an invar steel having a thermal expansion coefficient of about 1.0×10 ⁻⁶ /°C or a super invar material of about 1.0×10 ⁻⁷ /°C. Since the thermal expansion coefficient of the mask 100 of this material is very low, the pattern shape of the mask is less likely to be deformed by thermal energy, and it can be used as an FMM or a shadow mask in manufacturing high-resolution OLEDs. In addition, considering the recently developed technology for implementing the pixel deposition process within a range where the temperature change value is not large, the mask 100 may also be nickel (Ni), nickel-cobalt (Ni-Co) and other materials with a slightly larger thermal expansion coefficient . The thickness of the mask may be 2 μm to 50 μm.

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

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

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

The mask unit sheet portion 220 may include an edge sheet portion 221 and at least one of a first grid sheet portion 223 and a second grid sheet portion 225. The edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 refer to 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 square shape or a square shape corresponding to the edge frame portion 210.

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

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

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

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

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

For the mask unit sheet portion 220, the process of manufacturing a thick sheet is substantially difficult. If it is too thick, the organic matter source 600 (see FIG. 23) may block the path through the mask 100 in the OLED pixel deposition process . On the contrary, if it is too thin, it may be difficult to ensure sufficient rigidity to support the mask 100. Thus, the mask unit sheet portion 220 is preferably thinner than the thickness of the edge frame portion 210, but thicker than the mask 100. The thickness of the mask unit sheet portion 220 may be about 0.1 mm to 1 mm. In addition, the width of the first grid sheet portion 223 and the second grid sheet portion 225 may be approximately 1 to 5 mm.

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

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

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

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

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

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

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

Next, referring to (b) of FIG. 6, the mask unit sheet portion 220 is manufactured. The mask unit sheet portion 220 is manufactured by using electroforming or other film-forming processes to manufacture a planar sheet, and then removing the mask unit region CR by laser scribing, etching, or the like. In this specification, an example will be described in which 6×5 mask cell regions CR (CR11 to CR56) are formed. There may be five first grid sheet portions 223 and four second grid sheet portions 225.

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

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

7 is a schematic diagram showing a manufacturing process of a frame according to another embodiment of the present invention. The embodiment of FIG. 6 first manufactures the mask unit sheet portion 220 having the mask unit area CR, and then adheres to the edge frame portion 210, while the embodiment of FIG. 7 adheres the planar sheet to the edge frame portion 210. The mask unit area CR portion is formed.

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

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

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

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

FIG. 8 is a schematic diagram showing the shape of the mask 100 and the state where the mask 100 is attached to the tray 50 according to an embodiment of the present invention.

Referring to (a) of FIG. 8, a mask 100 formed with a plurality of mask patterns P may be provided. The mask 100 may include a mask unit C formed with a plurality of mask patterns P and a dummy part DM around the mask unit C. The dummy part DM partially corresponds to the mask film 110 except the cell C, and may include only the mask film 110 or may include the mask film 110 formed with a predetermined dummy part pattern similar to the shape of the mask pattern P. Corresponding to the edge of the mask 100, part or all of the virtual part DM may be adhered to the frame 200 [mask unit sheet part 220]. The mask 100 of Hengfan Steel and Ultra Hengfan Steel materials can be manufactured by electroforming.

In electroforming, a conductive material is used as a mother plate used as a cathode. As a conductive material, metal can generate metal oxides on the surface, impurities can flow into the metal manufacturing process, polysilicon substrates can contain inclusions or grain boundaries (Grain Boundary), conductive polymer substrates may contain impurities High performance, and may be weak in strength and acid resistance. Elements such as metal oxides, impurities, inclusions, and grain boundaries that hinder the uniform formation of an electric field on the surface of the motherboard (or cathode) are called "defects". Due to defects, a uniform electric field cannot be applied to the cathode of the above-mentioned material, which may result in uneven formation of a part of the plating film (mask 100).

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

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

In addition, single crystal materials can use metals such as Ti, Cu, Ag; GaN, SiC, GaAs, GaP, AlN, InN, InP, Ge and other semiconductors; graphite (graphite), graphene (graphene) and other carbon materials; including CH ₃ superconductor _{NH 3 PbCl 3, CH 3 NH} 3 PbBr 3, CH 3 NH 3 PbI 3, SrTiO 3 , etc. perovskite (Transition of perovskite) single crystal ceramic structure; aircraft parts and the like with the single crystal superalloy. Metal and carbon materials are basically conductive materials. In the case of semiconductor materials, in order to have conductivity, a high concentration doping of 1019 or more can be performed. Other materials can form conductivity by performing doping or forming oxygen vacancy. The doping may be performed on the entire 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, so a uniform plating film (mask 100) is generated. The frame-integrated masks 100 and 200 manufactured by uniform coating can further improve the image quality of OLED pixels. Moreover, since there is no need to perform additional processes for removing and eliminating defects, it is possible to reduce process costs and improve productivity.

In addition, if it is a single crystal material that can form an insulating film on the surface by silicon material or by oxidation (Oxidation), nitridation (Nitridation), it can be formed only by the surface oxidation and nitridation process of the motherboard as needed Advantages of insulation. The insulating portion may be formed using photoresist. In the portion where the insulating portion is formed, electrodeposition of the plating film (mask 100) is prevented, and a pattern (mask pattern P) is formed on the plating film.

In addition, as long as the material of the mother board of the present invention is within the range of reducing the defects of the cathode, it is not necessarily limited to the above single crystal material, and it is specifically stated.

The width of the mask pattern P may be less than 40 μm, and the thickness of the mask 100 may be about 2-50 μm. Since the frame 200 includes a plurality of mask unit regions CR (CR11 to CR56), a plurality of masks having mask units C (C11 to 56) corresponding to the respective mask unit regions CR (CR11 to CR56) may be formed. Hood 100.

The mask 100 can be adhered to the frame 200 by laser welding. The laser L can be irradiated to the welding part WP of the mask 100. The welding portion WP may indicate a target area where the laser beam L is irradiated to form the welding bead WB. The welding part WP may correspond to at least a part of the edge of the mask 100 or the part of the dummy part DM. Hereinafter, it is assumed that the plurality of welding parts WP are arranged at a certain distance from the virtual part DM area of the mask 100, and the shape of the welding part WP is substantially circular, but it is not necessarily limited to this, and it is specifically shown.

In addition, the mask 100 of the present invention is characterized in that the anti-crease patterns 150 to 170 are formed around the welding portion WP. The wrinkle-preventing patterns 150 to 170 are characterized by preventing laser beam L from being irradiated to the welding part WP to form a welding bead WB, preventing deformation caused by distortion or shrinkage of the periphery of the welding part WP [refer to FIGS. 14 and 15] .

The anti-wrinkle patterns 150 to 17 are similar to the mask pattern P, and are the same as the holes formed in the dummy portion DM [or edge portion] of the mask 100, and the anti-wrinkle pattern can be formed in the same way in the process of forming the mask pattern P Patterns 150~17. As an example, it may be a portion where the plating film 110 is not formed like the mask pattern P during the electroforming process of the mask 100, or a portion formed by a patterning process after performing the electroforming of the mask 100 .

The anti-crease patterns 150 to 170 are formed around a predetermined distance from the welded portion WP, and may be arranged as a whole to surround the welded portion WP or on both sides of the welded portion WP. For convenience of description, although (a) of FIG. 8 illustrates the anti-crease patterns 150 to 170 as simple patterns, the specific shapes involved in various embodiments will be described later with reference to FIGS. 9 to 12.

Then, referring to (b) and (c) of FIG. 8, the prepared mask 100 can be attached to the tray 50' (tray). The plated mask 100 can be peeled from the motherboard and attached to the tray 50'. In order to attach the mask 100 to one side of the tray 50' without wrinkles or wrinkles and spread it flatly, electrostatic force, magnetic force, vacuum, etc. may be used. The tray 50' may be a glass material that transmits laser light L.

9 to 12 are schematic diagrams showing anti-crease patterns 150 to 170 of a mask according to a plurality of embodiments of the present invention. 9 to 12 are enlarged parts of part D of FIG. 8. For ease of understanding, the mask unit C including the mask pattern P is shown on the right side. However, the size of the anti-crease patterns 150 to 170 and the buffer pattern 190 corresponding to the mask pattern P, the pattern arrangement positions, etc. It is not limited to those shown in Figs. 9 to 12, and is specifically expressed.

Referring to FIGS. 9 to 12, anti-crease patterns 150 to 170 may be formed around a predetermined distance from the welded portion WP. In one embodiment, the anti-crease patterns 150-170 and the welding portion WP are concentric WPCs, which can occupy the area on the circumference of the circle AC where the diameters R2 and R3 are larger than the diameter R1 of the welding portion WP. The form of the area occupying the circumference of the diameter R2, R3 larger than the diameter R1 of the welded part WP, when the unit anti-wrinkle pattern is arranged on the circumference, may be formed such that the unit anti-wrinkle pattern includes a part of the circumference itself.

Referring to FIG. 9, the anti-crease pattern 150 of the first embodiment may include a plurality of unit anti-crease patterns 151. In order to easily disperse the pressure and tension applied to the film of the mask 100, the unit anti-wrinkle patterns 151 are preferably in a form having a curvature such as a circle or an ellipse, compared to a form having an angle.

The plurality of unit anti-crease patterns 151 are arranged spaced apart from each other, and are concentric WPC with the welding portion WP, and may be arranged on the circumference of a hypothetical circle AC having a diameter R2 greater than the diameter R1 of the welding portion WP. The unit anti-crease pattern 151 may be arranged in one weight around the welded portion WP, and may also be arranged in two or three times.

In addition to the anti-crease pattern 150, a plurality of buffer patterns 190 may be formed. The buffer pattern 190 may be formed between the anti-crease pattern 150 and the mask pattern P at intervals. The buffer pattern 190 may be arranged along the inner edge of the virtual part DM area.

The buffer pattern 190 does not surround the periphery of the welded portion WP, and therefore serves to spread the pressure, tension, etc. applied to the film of the mask 100 in a wide range. Therefore, it may have a larger width than that of the mask pattern P, and may have a larger width than the anti-crease patterns 150-170. Furthermore, the buffer pattern 190 includes a plurality of unit buffer patterns 191 and 192. The unit buffer patterns 191 and 192 are also preferably in a form having a curvature such as a circle or an ellipse compared to a form having an angle.

According to an embodiment, the first unit buffer pattern 191 may be arranged on a horizontal axis passing through the middle of a pair of anti-crease patterns 150. Moreover, the second unit buffer pattern 192 may be arranged on the same horizontal axis as the first unit buffer pattern 191, or may be arranged on a horizontal axis passing through the middle of a pair of first unit buffer patterns 191. However, the arrangement form is not limited to these.

Referring to FIG. 10, the anti-crease pattern 160 of the second embodiment may include a plurality of unit anti-crease patterns 161.

A plurality of unit anti-crease patterns 161 are arranged spaced apart from each other, and are concentric WPC with the welding portion WP, and the shape thereof is at least a part 162, 163 of the circumference including the assumed circle AC, the diameter R2 of the above-mentioned assumed circle AC is larger than the welding portion The diameter R1 of WP. In other words, the unit anti-crease pattern 161 may include: at least a portion 162 of the circumference concentric with the specific welding portion WP1 and having a diameter larger than the diameter R2 of the specific welding portion WP1; and welding with the adjacent adjacent welding portion WP1 The portion WP2 is a concentric WPC and at least a portion 163 of the circumference of the diameter larger than the diameter R2 of the adjacent welding portion WP2. The unit anti-crease pattern 161 may include corner portions 164, 165 connecting them in addition to at least a part of the circumference 162, 163, and thus may have a closed pattern shape. Since the unit anti-crease pattern 161 includes local curvatures 162 and 163 at a certain distance from the welding portion WP, it has the advantage of easily dispersing the pressure and tension applied to the welding portion WP.

Referring to FIG. 11, the anti-crease pattern 160' according to the third embodiment may include a plurality of unit anti-crease patterns 161'.

The anti-crease pattern 160' according to the third embodiment is similar to the anti-crease pattern 160 according to the second embodiment, and may include curvature parts 162, 163. However, the shape of the anti-crease pattern 160' may include a closed pattern shape including parallel portions 166 and 162, 163 and corners 164 and 165 connecting the curvature portions 162, 163 and the parallel sides 166 facing each other. Since the unit anti-crease pattern 161 includes local curvatures 162 and 163 at a certain distance from the welded portion WP, it has the advantage of easily dispersing the pressure and tension applied to the welded portion WP.

Referring to FIG. 12, the anti-crease pattern 170 according to the fourth embodiment may include a plurality of unit anti-crease patterns 171.

The unit anti-crease pattern 171 and the welded part WP are concentric WPCs, which may have a shape including at least a portion 172 of the assumed circumference and at least a portion 173 of the assumed circumference, the at least a portion 172 having a larger diameter R1 than the welded portion WP At least a part of the assumed circumference of the first diameter R2, and the above-mentioned at least part 173 is at least a part of the assumed circumference of the second diameter R3 that is larger than the first diameter R1. The unit anti-crease pattern 171 includes not only at least a part of the circumference 172, 173, but also corners 174, 175 for connecting them, whereby it may have a closed pattern shape.

The plurality of unit anti-crease patterns 171 are spaced apart, and may be arranged to surround a welding portion WP. The unit anti-crease pattern 171 may be arranged in one weight around the welding portion WP, or may be arranged in two or three times. The unit anti-crease pattern 171 includes local curvatures 172 and 173 at a certain distance from the welded portion WP, and is arranged to surround the welded portion WP. Therefore, it has the advantage of easily distributing the pressure and tension applied to the welded portion WP.

FIG. 13 is a plan view showing the state of the mask 100′ according to the comparative example [FIG. 13(a)] and the state where the mask 100′ according to the comparative example is attached to the tray 50’ [FIG. 13(b)] and Side sectional view [(c) of FIG. 13]. 14 is a side cross-sectional view showing the state where the mask 100 according to the comparative example is adhered to the unit region CR of the frame 200 [FIG. 14( a )] and an enlarged plan view of E [FIG. 14( b )].

Referring to FIG. 13( a ), compared with the mask 100 of an embodiment of the present invention as described above in FIG. 8, the shape of the mask 100 ′ of the comparative example is that the mask unit C includes a plurality of masks Pattern P, and there is no additional pattern on the virtual part DM. Further referring to (b) and (c) of FIG. 13, the mask 100' can be attached to the tray 50' (tray). Furthermore, the plated mask 100 can be peeled off from the motherboard and attached to the tray 50'.

Referring to (a) of FIG. 14, part or all of the edge of the mask 100 may be adhered to the frame 200 [the first grid sheet portion 223 or the second grid sheet portion 225]. The bonding can be performed by welding, preferably by laser welding. Laser welding needs to be performed as close to the corner side of the frame 200 as possible, so that the warping space between the mask 100 and the frame 200 can be minimized, thereby improving adhesion.

On the upper part of the mask 100', the welding portion WP is irradiated with laser L, and the laser L can melt a part of the mask 100' in the area of the welding portion WP. A part of the mask 100' is melted, whereby a welding bead WB (bead) can be formed. Also, the welding bead WB may be a medium that connects the mask 100' and the frame 200 into one body.

At this time, in the process of melting and solidifying the mask 100' where the welding bead WB is formed, a tension T that shrinks the periphery of the welding bead WB is applied. Due to such a contracted tension T, wrinkles, twists, burrs and other deformations 105' occur around the welding bead WB. In addition, deformation 106' may occur in the space between the welding bead WB and the mask unit C, such as wrinkles and twists. Eventually, deformation 105', 106' occurs due to the tension T, and due to such deformation 105', 106', a problem occurs that the alignment state between the mask pattern P and the cell C is broken.

The mask 100 of the present invention can avoid the above-mentioned problems by forming the anti-crease patterns 150-170 and the buffer pattern 190.

15 is a schematic diagram showing a state where the mask 100 is bonded to the unit region CR of the frame 200 according to an embodiment of the present invention.

Referring to FIG. 15( a ), the welding portion WP of the dummy portion DM [or the edge area] of the mask 100 may be irradiated with laser light on the upper portion of the mask 100. Since a part of the mask 100 is melted, a welding bead WB (bead) is formed. Moreover, the welding bead WB may be a medium that connects the mask 100 and the frame 200 [or the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225] together.

At this time, during the process of melting and solidifying the mask 100 forming the portion of the welding bead WB, a tension T that shrinks the periphery of the welding bead WB is applied. The contraction tension T applied to the periphery of the welding bead WB can be dispersed to the anti-crease patterns 150 to 170, respectively. Since the tension T will be distributed to the plurality of anti-wrinkle patterns 150 to 170, the deformation 105' of wrinkles, twists, burrs, etc. around the welding bead WB will disappear.

Moreover, the contraction tension T applied to the space between the welding bead WB and the mask unit C is dispersed on the buffer pattern 190, respectively. Furthermore, since the tension T will be distributed to the plurality of buffer patterns 190, deformation 106' such as wrinkles and twists in the space between the solder bead WB and the mask unit C will disappear.

In this way, the deformations 105', 106' are eliminated due to the existence of a plurality of anti-crease patterns 150-170 and buffer patterns 190, or only at a level that hardly affects the alignment of the mask pattern P, so the mask 100 is bonded During the process of the frame 200, the alignment state between the mask pattern P and the cell C can be maintained.

FIG. 16 shows a plan view [FIG. 16(a)] and a side cross-sectional view [FIG. 16] showing a state in which the tray 50′ is loaded on the frame 200 so that the mask 100′ corresponds to the unit area CR of the frame 200 according to the comparative example. (B)]. 17 is a side cross-sectional view and part showing the process of loading the tray 50' on the frame 200 and bonding the mask 100' to the unit area CR of the frame 200 and the interface state of the mask 100 and the tray 50' according to the comparative example Enlarge the side view.

Referring to (a) and (b) of FIG. 16, the mask 100' may correspond to one mask unit region CR in the frame 200. The tray 50' on which the mask 100' is attached is turned upside down, and by loading the tray 50' on the frame 200 [or the mask unit sheet portion 220], the mask 100' corresponds to the mask unit region CR. If the tray 50' is loaded on the frame 200 [or the mask unit sheet portion 220], the mask 100' will be arranged between the tray 50' and the frame 200 [or the mask unit sheet portion 220] Squeezed by the tray 50'.

Referring to FIG. 17, the mask 100' is irradiated with laser L so that the mask 100' is bonded to the frame 200 by laser welding. A welding bead WB is generated on the welding part WP of the mask to be laser welded, and the welding bead WB may have the same material as the mask 100/frame 200 and be integrally connected with the mask 100/frame 200.

In addition to pressing the mask 100' by the tray 50', the pressing body M may be pressed from the upper part of the tray 50' to make the mask 100 and the frame 200 [or the edge sheet portion 221, the first The one grid sheet portion 223 and the second grid sheet portion 225] abut more closely. In addition to the load due to the weight of the extruded body M, a means for pressing the extruded body M may be provided. The extruded body M may be formed with a through hole MH through which the laser light L penetrates, and after passing through the through hole MH, the laser light passes through the tray 50' to irradiate the welded portion (the area to be welded) of the mask 100.

However, despite the load of the tray 50' and the extruded body M as described above, there may be a slight air gap AG at the interface between the tray 50' and the cover 100. Since the surface roughness Ra of the glass material tray 50' is about 20 to 30 mm, when the surface of the tray 50' is observed on the order of micrometers, there is inevitably a slight curvature. Thereby, even if the squeeze mask 100' still has a part where the tray 50' and the mask 100' are not in close contact, since the squeeze load is not well transmitted to this part, the mask 100' and the frame 200[ Or the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225] will not closely contact.

Between the tray 50' and the mask 100', there is no gap AG and the portion closely abuts, and the welding bead WB is easily generated between the mask 100' and the frame 200 by laser L1 irradiation, which connects the mask 100' with The frame 200 is connected into one body, and as a result, the welding operation can be completed smoothly. However, there is a gap AG between the tray 50' and the mask 100 that causes a portion that cannot be tightly contacted, and the welding bead WB cannot be easily generated between the mask 100 and the frame 200 based on laser L1 irradiation, and the result shows that it is not smooth To complete the welding operation.

Therefore, a feature of the present invention is to provide a tray 50 that can closely contact with the cover 100 without a gap AG.

18 is a side cross-sectional view and part showing the process of loading the tray 50 on the frame 200 and bonding the mask 100 to the unit area CR of the frame 200 and the interface state between the mask 100 and the tray 50 according to an embodiment of the present invention. Enlarge the side view. FIG. 19 is a plan view [(a) of FIG. 19] and a rear view [(b) of FIG. 19] showing a tray 50 according to an embodiment of the present invention. 20 is a schematic diagram showing a state in which the tray 50 is loaded on the frame 200 so that the mask 100 corresponds to the unit area CR of the frame 200 according to an embodiment of the present invention.

18 and 19, the mask 100 may be attached to the tray 50 (tray). The plated mask 100 is peeled off from the mother board and can be attached to the tray 50. The tray 50 is preferably in the shape of a flat plate, so that the cover 100 is attached to the tray 50 flatly. Moreover, the tray 50 may have a flat plate shape having a size larger than that of the mask 100 so that the mask 100 as a whole is attached to the tray 50 flatly.

In order to spread the mask 100 flatly on one surface of the tray 50 without wrinkles or wrinkles, an electrostatic force, a magnetic force, a vacuum, or the like can be used. The method of using static electricity is a method of rubbing the charged body and one side of the tray 50 to induce static electricity. Furthermore, the method of using electrostatic force is to apply a voltage to the transparent electrodes arranged above or below the tray 50. If a voltage is also applied to the mask 100, static electricity is induced to spread the mask 100 flatly In order to have a predetermined adhesion, the method of attaching the cover 100 to one side of the tray 50. The method of using magnetic force is a method of expanding the mask 100 while using a plurality of magnets on the opposite surface of the tray 50 on which the mask 100 is arranged to move the mask 100 with magnetic force. The method of using vacuum is a method of spreading the mask 100 while driving the mask 100 using a vacuum device from one end to the other end of the mask 100 arranged on the tray 50.

In particular, in order to prevent a gap AG from occurring at the interface between the tray 50 and the mask 100 of the present invention, the surface that is in contact with the mask 100 is a polished surface. Specifically, the surface roughness Ra of one side of the tray 50 may be 100 nm or less. The surface roughness Ra of the tray 50' of the ordinary glass material mentioned in FIG. 17 is about 20 to 30 mm, and therefore, the presence of the gap AG affects the alignment error of the mask pattern P at the ㎛ level. However, since the tray 50 of the present invention has a surface roughness Ra of the order of nm, there are no gaps AG or almost no gaps AG, so there is no influence on the alignment error of the mask pattern P.

In order to realize the tray 50 having a surface roughness Ra of 100 nm or less, a wafer can be used for the tray 50. The surface roughness Ra of the wafer is about 10 nm, and there are many products on the market. The surface treatment process is already known, so it is more suitable for the tray 50. In addition, if the surface is finely polished, the surface roughness Ra can meet 100nm or less, then the tray 50 can also use glass (glass), silica (silica), heat-resistant glass, quartz (quartz), alumina (Al ₂ O ₃ ) and other materials. In the following, it is assumed that a wafer is used as the tray 50.

Referring to the enlarged part of FIG. 18, it can be confirmed that there is no gap AG between the tray 50 having a surface roughness Ra of 50 nm or less and the interface of the mask 100 and closely contact. The welding part WP of the mask 100 is irradiated with laser light L to perform laser welding work.

On the other hand, the tray 50 of wafer material may be opaque to laser L light. Accordingly, the tray 50 of the present invention is characterized in that the laser through hole 51 is formed thereon, so that the laser light irradiated from the upper portion of the tray 50 can reach the welding portion WP of the mask 100.

Referring to (a) and (b) of FIG. 19, the laser through hole 51 may be formed on the tray 50 according to the position and number of the welded parts WP. The welding portion WP may be arranged at a predetermined interval on the edge of the mask 100 or a portion of the dummy portion DM. Therefore, a plurality of laser through holes 51 may be formed at a predetermined interval corresponding thereto. As an example, the welding part WP is arranged at predetermined intervals on the virtual parts DM on both sides (left/right) of the mask 100, so the laser through holes 51 may also be on both sides (left/right) of the tray 50. A plurality is formed at predetermined intervals.

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

The tray 50 may also be provided with an extruding body M to squeeze, so that the mask 100 and the frame 200 [or the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225] Close contact. In addition to the load due to the weight of the pressing body M, a means for pressing the pressing body M may be provided. The extruded body M may be formed with a transmission hole MH through which the laser light L penetrates, and the formation area of the transmission hole MH may overlap the formation area of the laser through hole 51 of the tray 50. After the laser light L penetrates the through hole MH, it passes through the tray 50 to irradiate the welding portion WP of the mask 100. Welding W should be performed as close as possible to the corner side of the frame 200 to minimize the warping space between the cover 100 and the frame 200 and improve the adhesion.

The tray 50 and the cover 100 may closely contact without the gap AG. Due to the compression caused by the upper extruded body M and the load of the tray 50, the tray 50 and the cover 100, the cover 100 and the frame 200 [or The edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 can more closely abut. Thereby, the welding bead WB can be generated well between the mask 100 and the frame 200 by the irradiation of the laser L. The welding bead WB can be regarded as a portion where the mask 100 is melted, and has a spot or line shape, and serves as a medium to connect the mask 100 and the frame 200 into one body, and finally, the welding is smoothly performed.

Then, referring to (a) and (b) of FIG. 20, the mask 100 may correspond to one mask unit region CR of the frame 200. Reverse the tray 50 with the mask 100 attached thereon, and by loading the tray 50 on the frame 200 [or the mask unit sheet portion 220], the mask 100 can correspond to the mask unit area CR. Furthermore, while controlling the position of the tray 50, it is observed with a microscope whether the mask 100 corresponds to the mask unit area CR. When the tray 50 is loaded on the frame 200 [or the mask unit sheet portion 220], the mask 100 is placed between the tray 50 and the frame 200 [or the mask unit sheet portion 220], and the tray 50 is used Squeeze the mask 100.

On the other hand, the lower support 70 may also be arranged below the frame 200. The lower support 70 has a size that can enter the inside of the hollow region R of the frame edge portion 210 and has a flat shape. Furthermore, a predetermined support groove (not shown) corresponding to the shape of the mask unit sheet portion 220 may be formed on the upper surface of the lower support 70. At this time, the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 are inserted into the support grooves, so that the mask unit sheet portion 220 is better fixed.

The lower support 70 may press the opposite surface of the mask unit region CR that is in contact with the mask 100. That is, the lower support 70 supports the mask unit sheet portion 220 in the upper direction, thereby preventing the mask unit sheet portion 220 from sagging downward when the mask 100 is bonded. At the same time, the lower support 70 and the tray 50 press the edge portion of the mask 100 and the frame 200 [or the mask unit sheet portion 220] in opposite directions to each other, so that the alignment state of the mask 100 can be maintained without breaking Keep aligned.

The feature of the present invention is that the process of matching the mask 100 to the mask unit area CR of the frame 200 can be completed only by attaching the mask 100 on the tray 50 and loading the tray 50 on the frame 200. 100 does not apply any stretching force.

Since the mask unit sheet portion 220 of the frame 200 has a thin thickness, when a tensile force is applied to the mask 100, when the mask unit sheet portion 220 is adhered to the mask unit sheet 220, the tensile force remaining in the mask 100 acts The mask unit sheet portion 220 and the mask unit region CR may be deformed. Therefore, the mask 100 should be adhered to the mask unit sheet portion 220 in a state where no stretching force is applied to the mask 100. Thereby, it is possible to prevent deformation of the frame 200 (or the mask unit sheet portion 220) due to the tensile force applied to the mask 100 acting as a tension on the frame 200 in reverse.

However, the mask 100 is adhered to the frame 200 (or the mask unit sheet portion 220) in a state where no tensile force is applied to manufacture a frame-integrated mask, and the frame-integrated mask is applied During the pixel deposition process, a problem may occur. In the pixel deposition process performed at about 25 to 45°C, the mask 100 thermally expands by a prescribed length. Even for the mask 100 of Hengfan steel material, as the temperature for forming the pixel deposition process environment is increased by about 10°C, a length change of about 1 to 3 ppm will occur. For example, when the total length of the mask 100 is 500 mm, the length can be increased by about 5-15 μm. In this way, the mask 100 sags due to its own weight or stretches while being fixed to the frame 200 to cause distortion such as twisting, and at the same time, the alignment error of the pattern P becomes large.

Therefore, the present invention is characterized in that the mask 100 corresponds to and adheres to the mask unit region CR of the frame 200 at a temperature higher than the normal temperature instead of the normal temperature without applying a tensile force to the mask 100. . In this specification, it is expressed that after raising the temperature of the process area to the first temperature ET, the mask is made to correspond to and adhere to the frame.

The “process area” refers to a space in which components such as the mask 100 and the frame 200 are arranged and the bonding process of the mask 100 is performed. The process area can be a space in a closed chamber or an open space. In addition, the "first temperature" may refer to a temperature higher than or equal to the pixel deposition process when the frame-integrated mask is used in the OLED pixel deposition process. Considering that the temperature of the pixel deposition process is about 25~45°C, the first temperature may be about 25°C to 60°C. The temperature of the process area can be increased by installing a heating device in the chamber or a heating device around the process area.

Referring again to FIG. 13, after the mask 100 corresponds to the mask unit area CR, the temperature of the process area including the frame 200 may be raised to the first temperature ET. Alternatively, after raising the temperature of the process area including the frame 200 to the first temperature, the mask 100 may correspond to the mask unit area CR. The drawing shows that only one mask 100 corresponds to one mask cell area CR, or that multiple masks 100 correspond to each mask cell area CR, and then the temperature of the process area is raised to the first temperature ET .

The existing mask 10 of FIG. 1 includes six cells C1 to C6, and thus has a long length, and the mask 100 of the present invention includes one cell C, and thus has a short length, so PPA (pixel position accuracy) is distorted The degree can be reduced. Assuming that the length of the mask 10 including a plurality of cells C1 to C6, is 1 m, and a PPA error of 10 μm occurs in the total length of 1 m, the mask 100 of the present invention can decrease with the relative length (equivalent As the number of cells C decreases), the above error range becomes 1/n. For example, the length of the mask 100 of the present invention is 100 mm, which has a length reduced from 1 m of the existing mask 10 to 1/10, so a PPA error of 1 μm occurs in the total length of 100 mm, which significantly reduces the alignment error.

On the other hand, the mask 100 includes a plurality of cells C, and even if each cell C corresponds to each cell region CR of the frame 200 within the range of minimizing the alignment error, the mask 100 can be Each mask unit area CR corresponds. Alternatively, the mask 100 having a plurality of cells C may correspond to one mask cell region CR. In this case, also considering the process time and productivity based on the alignment, the mask 100 preferably has as few cells C as possible.

In the present invention, since it is only necessary to match one unit C of the mask 100 and confirm the alignment state, compared with the existing method of simultaneously matching a plurality of units C (C1 to C6) and needing to confirm all alignment states, Can significantly reduce manufacturing time.

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

In addition, in the manufacturing method of the frame-integrated mask of the present invention, the product yield in the process of aligning 30 masks 100 with 30 unit regions CR (CR11 to CR56) respectively and 30 times can be This is significantly higher than the yield of the existing product in the process of five times in which five masks 10 (refer to (a) of FIG. 2) including six cells C1 to C6 are respectively aligned and aligned with the frame 20. Since the existing method of aligning 6 cells C1 to C6 in the area corresponding to 6 cells C at a time is obviously a tedious and difficult operation, the product yield is low.

On the other hand, after matching the mask 100 to the frame 200, the mask 100 may be temporarily fixed to the frame 200 with a predetermined adhesive. Then, the bonding step of the mask 100 may be performed.

21 is a plan view [FIG. 21(a)] and a side cross-sectional view [FIG. 21(b) showing a process of sequentially bonding the mask 100 to the cell region CR (CR11 to CR56) according to an embodiment of the present invention. )].

Referring to FIG. 21, after the mask 100 is correspondingly bonded to the mask unit region CR11, the mask 100 may be correspondingly bonded to the mask unit region CR12 adjacent to the mask unit region CR11. Although FIG. 21 illustrates that only two masks 100 are bonded, the mask 10 may be bonded correspondingly on all the mask unit regions CR.

It is shown that one edge of two adjacent masks 100 is bonded (formed a solder bead WB) to the upper surface of the first grid sheet portion 223 (or the second grid sheet portion 225). The width and thickness of the first grid sheet portion 223 (or the second grid sheet portion 225) are about 1 to 5 mm. To improve the productivity of the product, it is necessary to change the first grid sheet portion 223 (or The width of the second grid sheet portion 225) overlapping the edge of the mask 100 is reduced to about 0.1 to 2.5 mm to the maximum.

In a state where no tensile force is applied to the mask 100, it is welded LW to the mask unit sheet portion 220, so the mask unit sheet portion 220 (or the edge sheet portion 221), the first grid The grid sheet portion 223 and the second grid sheet portion 225 apply tension.

After one mask 100 is adhered to the frame 200, the process of making the remaining mask 100 correspond to the remaining mask units C in sequence and adhere to the frame 200 may be repeated. Since the mask 100 that has been adhered to the frame 200 can provide a reference position, it is possible to significantly shorten the time in the process of making the remaining masks 100 sequentially correspond to the cell regions CR and confirm the alignment state. In addition, the PPA (pixel position accuracy) between the mask 100 adhered to one mask unit area and the mask 100 adhered to the adjacent mask unit area does not exceed 3 μm, which can provide ultra-high-definition OLED pixels with accurate alignment Mask for formation.

22 is a schematic diagram showing a process of lowering the temperature LT of the process area after bonding the mask 100 to the unit area CR of the frame 200 according to an embodiment of the present invention.

Then referring to FIG. 22, the temperature of the process area may be reduced to the second temperature LT. "Second temperature" refers to a temperature lower than the first temperature. Considering that the first temperature is about 25°C to 60°C, and on the premise of being lower than the first temperature, the second temperature may be about 20°C to 30°C, preferably, the second temperature may be normal temperature. The temperature of the process area can be reduced by installing a cooling device in the chamber, a cooling device around the process area, or a natural cooling method at room temperature.

When the temperature of the process area is reduced to the second temperature LT, the mask 100 may be thermally contracted by a prescribed length. The mask 100 can be thermally contracted isotropically along all lateral directions. However, since the mask 100 is fixedly connected to the frame 200 [or the mask unit sheet portion 220] by welding, the thermal shrinkage of the mask 100 spontaneously applies tension TS to the surrounding mask unit sheet portion 220. Since the mask 100 spontaneously applies tension, the mask 100 can be more closely adhered to the frame 200.

In addition, after all the masks 100 are all bonded to the corresponding mask unit area CR, the temperature of the process area is reduced to the second temperature LT, so that all the masks 100 are thermally contracted at the same time, thereby preventing the frame 200 from being deformed or the pattern P The alignment error becomes larger. More specifically, even if the tension TS is applied to the mask unit sheet portion 220, the plurality of masks 100 apply the tension TS in the opposite direction, so that the force is offset, and the mask unit sheet portion 220 is not deformed. For example, in the first grid sheet portion 223 between the mask 100 attached to the CR11 unit area and the mask 100 attached to the CR12 unit area, the first grid sheet portion 223 acts on the right side of the mask 100 attached to the CR11 unit area The tension TS and the tension TS acting in the left direction of the mask 100 attached to the CR12 cell area cancel each other. Thereby, the deformation of the frame 200 [or the mask unit sheet portion 220] based on the tension TS is minimized, and the alignment error of the mask 100 [or mask pattern P] can be minimized.

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

Referring to FIG. 23, the OLED pixel deposition apparatus 1000 includes: a magnetic plate 300 containing a magnet 310 and cooling water pipes 350 arranged; and a deposition source supply part 500 that supplies organic raw material 600 from a lower portion of the magnetic plate 300.

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

The deposition source supply part 500 can feed the organic matter source 600 to and from the left and right paths, and the organic substance source 600 supplied by the deposition source supply part 500 can be adhered to one side of the target substrate 900 by the pattern P formed in the frame-integrated masks 100 and 200 . The organic matter source 600 deposited after the pattern P of the frame-integrated masks 100 and 200 can be used as the pixel 700 of the OLED.

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

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

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

10: Strip mask 11: Mask film 20: Frame 50, 50’: tray 51: Laser penetrating hole 70: lower support 100: mask 110: mask film 150, 160, 160’, 170: anti-crease pattern 151, 161, 161’, 171: unit anti-crease pattern 190: buffer pattern 191, 192: unit buffer pattern 200: frame 210: Edge frame part 220: Mask unit sheet section 221: Edge sheet section 223: First grid sheet section 225: Second grid sheet section 300: magnetic board 310: magnet 350: cooling water pipe 500: deposition source supply department 600: Organic raw materials 700: pixels 900: target substrate 1000: OLED pixel deposition device C: Unit, mask unit C1~C3: Mask unit CR: mask unit area D1~D1”, D2~D2”: distance DM: virtual part, mask virtual part ET: Raise the temperature of the process area to the first temperature F1~F2: tensile force L: Laser LT: Reduce the temperature of the process area to the second temperature M: upper extruded body P: Mask pattern R: Hollow area of the edge frame TS: Tension W: welding WB: Welding welding beads WP: Welding Department WPC: Welding center point

FIG. 1 is a schematic diagram showing a conventional mask for OLED pixel deposition. FIG. 2 is a schematic diagram showing a process of bonding a conventional mask to a frame. FIG. 3 is a schematic diagram showing that an alignment error between cells occurs during a conventional stretching mask. 4 is a plan view and a side cross-sectional view showing a frame-integrated mask according to an embodiment of the present invention. 5 is a plan view and a side sectional view showing a frame according to an embodiment of the present invention. 6 is a schematic diagram showing a frame manufacturing process according to an embodiment of the present invention. 7 is a schematic diagram showing a frame manufacturing process according to another embodiment of the present invention. FIG. 8 is a schematic diagram showing the shape of the mask and the state where the mask is attached to the tray according to an embodiment of the present invention. 9 to 12 are schematic diagrams showing mask anti-crease patterns according to various embodiments of the present invention. FIG. 13 is a schematic view showing a state of bonding the mask disk in a comparative example. 14 is a schematic diagram showing a state in which a mask is adhered to a unit area of a frame according to a comparative example. 15 is a schematic diagram showing a state in which a mask is adhered to a unit area of a frame according to an embodiment of the present invention. 16 is a schematic view showing a state in which a tray is loaded on a frame so that a mask corresponds to a unit area of the frame according to a comparative example. 17 is a schematic diagram showing a process of loading a tray on a frame and adhering a mask to a unit area of the frame according to a comparative example, and an interface state between the mask and the tray. 18 is a schematic diagram showing a process of loading a tray on a frame and adhering a mask to a unit area of the frame and an interface state between the mask and the tray according to an embodiment of the present invention. 19 is a schematic diagram showing a tray according to an embodiment of the present invention. 20 is a schematic diagram showing a state in which a tray is loaded on a frame so that a mask corresponds to a unit area of the frame according to an embodiment of the present invention. 21 is a schematic diagram showing a process of sequentially bonding a mask to a cell area according to an embodiment of the present invention. 22 is a schematic diagram showing a process of lowering the temperature of the process area after bonding the mask to the unit area of the frame according to an embodiment of the present invention. 23 is a schematic diagram showing an OLED pixel deposition apparatus using a frame-integrated mask according to an embodiment of the present invention.

50’: tray

100: mask

110: mask film

150, 160, 170: anti-crease pattern

C: unit/mask unit

P: pattern/mask pattern

WP: Welding Department

DM: mask virtual part

Claims (15)

A mask for forming an OLED pixel, which includes a mask unit formed with a plurality of mask patterns; and a virtual part located around the mask unit, At least a part of the virtual part is formed with a plurality of spaced apart welding parts, An anti-wrinkle pattern is formed around each welding portion at a predetermined distance. The mask for forming an OLED pixel according to claim 1, wherein the anti-wrinkle pattern is concentric with the welded portion, and it occupies at least an area on the circumference whose diameter is larger than the diameter of the welded portion. As in the mask for forming an OLED pixel of claim 2, wherein the anti-crease pattern includes a plurality of unit anti-crease patterns, The unit anti-crease pattern is any one of round and oval. The mask for forming an OLED pixel according to claim 3, wherein the plurality of unit anti-wrinkle patterns are concentric with the welded portion, which are arranged at least spaced apart from each other on a region on the circumference whose diameter is larger than the diameter of the welded portion. As in the mask for forming an OLED pixel of claim 2, wherein the anti-crease pattern includes a plurality of unit anti-crease patterns, The unit anti-wrinkle pattern is concentric with the welded portion, and its shape includes at least a part of the circumference whose diameter is larger than the diameter of the welded portion. The mask for forming an OLED pixel according to claim 5, wherein the shape of one unit anti-crease pattern is a shape of a closed pattern, which is connected to at least a part of a circle concentric with the specific welded portion and having a diameter larger than the diameter of the specific welded portion, and The welding portion adjacent to the specific welding portion is concentric and has a diameter larger than at least a part of the circumference of the adjacent welding portion. The mask for forming an OLED pixel according to claim 6, wherein the adjacent pair of unit anti-wrinkle patterns further includes a closed pattern shape of sides facing each other and parallel. As in the mask for forming an OLED pixel of claim 2, wherein the anti-crease pattern includes a plurality of unit anti-crease patterns, The shape of the unit anti-crease pattern is a shape of a closed pattern that connects at least a part of a circle concentric with the welding site and having a diameter larger than the first diameter of the welded portion and at least a part of the circle having a second diameter larger than the first diameter . The mask for forming an OLED pixel according to claim 8, wherein a plurality of unit anti-crease patterns are arranged spaced apart from each other, thereby surrounding one welding portion. The mask for forming an OLED pixel according to claim 1, wherein the anti-wrinkle pattern and the mask pattern are formed spaced apart from each other, and further include a plurality of buffer patterns having a width larger than the mask pattern. The mask for forming an OLED pixel according to claim 10, wherein the shape of the unit buffer pattern is any one of a circle and an ellipse. A method for manufacturing a frame-integrated mask in which at least one mask and a frame supporting the mask are formed as an integrated body includes: (A) The step of providing a frame with at least one mask unit area; (B) The step of matching the mask to the mask unit area of the frame; and (C) The step of irradiating laser to the welding part of the mask to make the mask adhere to the frame, The mask includes a mask unit formed with a plurality of mask patterns; and an imaginary part located around the mask unit, at least a part of the imaginary part is formed with a plurality of welding parts spaced apart from each other, and is spaced apart from each welding part Anti-crease patterns are formed around the distance. The manufacturing method of the frame-integrated mask of claim 12, wherein, (B) The steps are steps of attaching the mask to the tray, loading the tray on the frame, and masking the mask unit area corresponding to the frame. The manufacturing method of the frame-integrated mask of claim 12, wherein the anti-wrinkle pattern is concentric with the welded portion, and occupies at least an area on the circumference whose diameter is larger than the diameter of the welded portion. The manufacturing method of the frame-integrated mask of claim 12, wherein the anti-crease pattern and the mask pattern are formed spaced apart from each other, and further include a plurality of buffer patterns having a width greater than the width of the mask pattern.

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