CN118600493A

CN118600493A - Frame-integrated mask and method for manufacturing frame-integrated mask

Info

Publication number: CN118600493A
Application number: CN202410503781.XA
Authority: CN
Inventors: 李裕进
Original assignee: Wulaomao Materials Co ltd
Current assignee: Wulaomao Materials Co ltd
Priority date: 2018-02-09
Filing date: 2018-12-26
Publication date: 2024-09-06
Also published as: KR20190096577A; TW201936950A; CN111656552A; WO2019156348A1; TWI835771B

Abstract

The present invention relates to a frame-integrated mask and a method for manufacturing the frame-integrated mask. The frame-integrated mask according to the present invention, which is integrally formed of a plurality of masks (100) and a frame (200) for supporting the masks (100), is characterized in that the frame (200) has: an edge frame portion (210) comprising a hollow region (R); and a mask unit sheet section (220) which has a plurality of mask unit regions (CR) and is connected to the edge frame section (210), wherein each mask (100) is connected to the upper part of the mask unit sheet section (220).

Description

Frame-integrated mask and method for manufacturing frame-integrated mask

The present application is a divisional application of the application patent application with international application number PCT/KR2018/016653, international application date 2018, 12 month and 26 date, national stage date 2020, 7 month and 14 date, national application number 201880086540.2, and the application name "frame-integrated mask and method for manufacturing frame-integrated mask".

Technical Field

The present invention relates to a frame-integrated mask and a method for manufacturing the frame-integrated mask, and more particularly, to a frame-integrated mask and a method for manufacturing the frame-integrated mask, which can integrate the mask with the frame and accurately perform alignment (alignment) between the masks.

Background

Recently, studies on an electroforming (Electroforming) method in sheet manufacturing are continuously being conducted. The electroforming method is a method capable of manufacturing an extremely thin plate and desired mass production, because a thin metal plate is electrodeposited on the surface of a cathode by immersing the anode and the cathode in an electrolyte and applying a power source.

On the other hand, as a technique for forming pixels in the OLED process, an FMM (FINE METAL MASK, precision metal Mask) method is mainly used, which evaporates an organic substance to a desired position by attaching a metal Mask (Shadow Mask) of a thin film to a substrate.

In the conventional OLED manufacturing process, after manufacturing a mask in a rod shape, a plate shape, or the like, the mask is welded and fixed to an OLED pixel vapor deposition frame and used. One mask may have a plurality of cells corresponding to one display. In addition, in order to manufacture a large area OLED, a plurality of masks may be fixed to the OLED pixel evaporation frame, however, each mask may be flattened by stretching during the fixing to the frame. Adjusting the stretching force in order to flatten the mask as a whole is a very difficult task. In particular, in order to align mask patterns having a size of several to several tens of μm while planarizing each cell, the following highly difficult operations are required: while the tension applied to each side of the mask was finely adjusted, the alignment state was confirmed in real time.

However, in the process of fixing a plurality of masks to one frame, there is a problem in that alignment between masks and between mask units is not good. In addition, in the process of welding and fixing the mask to the frame, since the thickness of the mask film is too thin and the area is large, there is a problem in that the mask sags or warps due to the load.

For ultra-high quality OLEDs, the current QHD image quality is 500-600PPI (pixel per inch), the size of the pixel reaches about 30-50 μm, and 4K UHD, 8K UHD high image quality has higher resolution of-860 PPI, -1600 PPI, etc. Considering the pixel size of an OLED with ultra-high image quality, it is necessary to reduce the alignment error between units by about several μm, and exceeding this error leads to poor product, so the yield may be extremely low. Therefore, there is a need to develop a technique capable of preventing deformation such as sagging or twisting of the mask and making alignment accurate, a technique of fixing the mask to the frame, and the like.

Disclosure of Invention

Technical problem to be solved

The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a frame-integrated mask and a method for manufacturing the frame-integrated mask, which can form a mask and a frame into a single structure.

The present invention also provides a frame-integrated mask and a method for manufacturing the frame-integrated mask, which can prevent deformation such as sagging or warping of the mask and can accurately perform alignment.

The present invention also aims to provide a frame-integrated mask and a method for manufacturing the frame-integrated mask, which can significantly reduce the manufacturing time and significantly improve the yield.

Solution to technical problems

The above object of the present invention is achieved by a frame-integrated mask formed integrally with a frame for supporting a mask from a plurality of masks, wherein the frame comprises: an edge frame portion including a hollow region; and a mask unit sheet portion having a plurality of mask unit regions and connected to the edge frame portion, each mask being connected to an upper portion of the mask unit sheet portion.

The mask unit sheet portion may have a plurality of mask unit regions along at least one of a first direction and a second direction perpendicular to the first direction.

The mask unit sheet portion may include: an edge sheet portion; and at least one first grid sheet portion formed extending in the first direction and connected at both ends to the edge sheet portion.

The mask unit sheet portion may further include at least one second grid sheet portion formed to extend in a second direction perpendicular to the first direction and intersecting the first grid sheet portion, and both ends thereof are connected to the edge sheet portion.

Each mask may correspond to each mask cell region.

The mask may include a mask unit formed with a plurality of mask patterns and a dummy portion at a periphery of the mask unit, and at least a portion of the dummy portion is adhered to the mask unit sheet portion.

The mask may include one mask unit, and each mask corresponds to each mask unit region of the mask unit sheet portion.

Each mask may include a plurality of mask units, and each mask corresponds to each mask unit region of the mask unit sheet portion.

The edge frame portion may be in the shape of a square.

The thickness of the edge frame portion may be thicker than the thickness of the mask unit sheet portion, and the thickness of the mask unit sheet portion may be thicker than the mask.

The thickness of the mask unit sheet portion may be 0.1 to 1mm, and the thickness of the mask may be 2 to 50 μm.

The mask and frame may be any of invar (invar), super invar (super invar), nickel cobalt.

The pixel position accuracy (PPA: pixel position accuracy) between the mask attached to one mask unit region and the mask attached to the mask unit region of the mask adjacent thereto may be not more than 3 μm.

Further, the above object of the present invention can be achieved by a method of manufacturing a frame-integrated mask formed integrally with a frame for supporting a mask from a plurality of masks, the method comprising: (a) Providing an edge frame portion including a hollow region; (b) A step of connecting a mask unit sheet portion having a plurality of mask unit regions to the edge frame portion; (c) A step of associating a mask with one mask unit region of the mask unit sheet portion; and (d) a step of adhering at least a part of the mask edge to the mask unit sheet portion.

Further, the above object of the present invention can be achieved by a method of manufacturing a frame-integrated mask formed integrally with a frame for supporting a mask from a plurality of masks, the method comprising: (a) Providing an edge frame portion including a hollow region; (b) A step of connecting the planar mask unit sheet portion to the edge frame portion; (c) A step of forming a plurality of mask unit regions on the mask unit sheet portion; (d) A step of associating the mask with one mask unit region of the mask unit sheet portion; and (e) a step of adhering at least a part of the mask edge to the mask unit sheet portion.

Each mask may correspond to each mask cell region.

In step (b), the corner portions of the mask unit sheet portion may be welded and connected to the edge frame portion.

The mask may include one mask unit, and one mask unit may be located in one mask unit region.

The mask may include a plurality of mask units, and the plurality of mask units may be located within one mask unit region.

Advantageous effects

According to the present invention as described above, there is an effect that the mask and the frame are formed into a unitary structure.

Further, according to the present invention, there is an effect that deformation such as sagging or twisting of the mask can be prevented and alignment can be accurately performed.

Further, according to the present invention, the production time can be significantly shortened and the yield can be significantly improved.

Drawings

Fig. 1 is a schematic diagram showing a prior art mask for OLED pixel evaporation.

Fig. 2 is a schematic view showing a process of attaching a conventional mask to a frame.

Fig. 3 is a schematic view showing alignment errors between cells occurring during stretching of the existing mask.

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

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

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

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

Fig. 8 is a schematic view showing a stretched form of a mask and a state of the mask corresponding to a cell region of a frame according to an embodiment of the present invention.

Fig. 9 is a schematic view showing a process of corresponding a mask to a unit area of a frame and pasting according to an embodiment of the present invention.

Fig. 10 is a partially enlarged cross-sectional view showing a state in which a mask is attached to a frame according to various embodiments of the present invention.

Fig. 11 is a schematic view showing an OLED pixel vapor deposition apparatus using a frame-integrated mask according to an embodiment of the present invention.

[ Reference numerals ]

100: Mask for mask

110: Mask film

150: Adhesive plating part

200: Frame

210: Edge frame portion

220: Mask unit sheet portion

221: Edge sheet portion

223: First grid sheet portion

225: Second grid sheet portion

1000: OLED pixel evaporation device

C: unit, mask unit

CR: mask unit region

EM: eutectic material bonding part

F1 to F4: tension force

R: hollow region of edge frame portion

P: mask pattern

W: welding

Detailed Description

The invention will now be described in detail with reference to the drawings, which are intended to illustrate examples of specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. The various embodiments of the invention should be understood as being different from each other and not mutually exclusive. For example, the particular shapes, structures and characteristics described herein may enable one embodiment to be implemented as other embodiments without departing from the spirit and scope of the invention. In addition, the location or arrangement of individual elements within each disclosed embodiment may be modified without departing from the spirit and scope of the invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled. Like reference numerals in the drawings designate the same or similar functions through various aspects, and lengths, areas, thicknesses, etc. and forms thereof may be exaggerated for convenience.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings so as to enable those skilled in the art to easily practice the present invention.

Fig. 1 is a schematic diagram showing a prior art mask 10 for OLED pixel evaporation.

Referring to fig. 1, the existing mask 10 may be manufactured in a Stick-Type (Stick-Type) or a Plate-Type (Plate-Type). The mask 10 illustrated in fig. 1 (a) is a bar-type mask, and both sides of the bar may be welded and fixed to the OLED pixel vapor deposition frame for use. The mask 100 illustrated in fig. 1 (b) is a Plate-Type (Plate-Type) mask, and may be used for a large-area pixel formation process.

The Body (Body) of the mask 10 (or the mask film 11) has a plurality of display cells C. One unit C corresponds to one display of a smart phone or the like. The unit C has a pixel pattern P formed therein to correspond to each pixel of the display. If the cell C is enlarged, a plurality of pixel patterns P corresponding to R, G, B are presented. As an example, the cell C is formed with a pixel pattern P of 70×140 resolution. That is, various pixel patterns P are clustered to form one cell C, and a plurality of cells C may be formed on the mask 10.

Fig. 2 is a schematic view showing a process of attaching the conventional mask 10 to the frame 20. Fig. 3 is a schematic diagram showing the occurrence of the alignment error between cells during the stretching of the conventional mask 10 of F1 to F2. A stick mask 10 having 6 cells C (C1 to C6) illustrated in fig. 1 (a) is described as an example.

Referring to fig. 2 (a), first, the stick type mask 10 must be spread flat. The bar mask 10 is stretched by applying the stretching forces F1 to F2 in the longitudinal direction of the bar mask 10. In this state, the bar mask 10 is mounted on the rectangular frame 20. The cells C1-C6 of the stick mask 10 will be located in the blank area portion inside the rim of the frame 20. The frame 20 may be the size of the blank space where the cells C1 to C6 of one bar type mask 10 are located inside the frame, or the size of the blank space where the cells C1 to C6 of a plurality of bar type masks 10 are located inside the frame.

Referring to fig. 2 (b), while the tensile forces F1 to F2 applied to the respective sides of the bar-type mask 10 are finely adjusted, alignment is performed, and then a portion of the side surfaces of the bar-type mask 10 is welded W, thereby connecting the bar-type mask 10 and the frame 20 to each other. Fig. 2 (c) shows a side cross-sectional view of the bar-type mask 10 and the frame that have been attached to each other.

Referring to fig. 3, although the tensile forces F1 to F2 applied to each side of the bar-type mask 10 are finely adjusted, there is a problem in that the mask units C1 to C3 are not aligned well. For example, the patterns P of the cells C1 to C3 are separated by distances D1 to D1 ", D2 to D2" from each other or the patterns P are skewed. The stick mask 10 is a large area including a plurality of (6, for example) cells C1 to C6, and has a very thin thickness in the order of tens of μm, and thus may easily sag or twist due to a load. In addition, it is very difficult to confirm the alignment state of the units C1 to C6 in real time by a microscope while adjusting the tensile forces F1 to F2 so that the units C1 to C6 are all flattened.

Therefore, the small errors in the stretching forces F1 to F2 cause errors in the stretching or developing degrees of the respective cells C1 to C3 of the bar-type mask 10, and thus, the distance D1 to D1″ and the distance D2 to D2″ between the mask patterns P may be different. Of course, it is difficult to make the error 0 by perfect alignment, but in order that the mask pattern P having a size of several to several tens of μm does not adversely affect the pixel process of the ultra-high image quality OLED, the alignment error preferably does not exceed 3 μm. The alignment error between such adjacent cells is referred to as pixel position accuracy (pixel position accuracy).

In addition, when a plurality of bar-type masks 10, about 6 to 20, are connected to one frame 20, it is very difficult to precisely align the bar-type masks 10 and the cells C to C6 of the bar-type masks 10, and the alignment only increases the process time, which is a significant factor in reducing the production efficiency.

Based on this, the present invention proposes a frame 200 and a frame-integrated mask in which the mask 100 and the frame 200 are formed as a single structure. The mask 100 integrally formed on the frame 200 can prevent sagging or distortion, etc., and can be accurately aligned with the frame 200. In addition, the present invention has an advantage in that the manufacturing time for integrally connecting the mask 100 to the frame 200 can be significantly shortened and the yield can be significantly improved.

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

Referring to fig. 4 and 5, the frame-integrated mask may include a plurality of masks 100 and one frame 200. In other words, the plurality of masks 100 are individually attached to the frame 200. In the following, for convenience of explanation, the rectangular mask 100 will be described as an example, but the mask 100 is in the form of a bar-shaped mask having protrusions for clamping on both sides before being attached to the frame 200, and the protrusions can be removed after being attached to the frame 200.

A plurality of mask patterns P are formed on each mask 100, and one cell C may be formed on one mask 100. One mask unit C may correspond to one display of a smart phone or the like. To form a thinner thickness, the mask 100 may be formed by electroforming (electroforming). Mask 100 may be a invar (invar) material having a coefficient of thermal expansion of about 1.0x10 ^-6/°c, a super invar (super invar) material having a coefficient of thermal expansion of about 1.0x10 ^-7/°c. The Mask 100 of the material has a very low thermal expansion coefficient and a Mask pattern shape is less likely to be deformed by thermal energy, so that it can be used as an FMM (FINE METAL MASK: fine metal Mask) or Shadow Mask (Shadow Mask) in high resolution OLED manufacturing. In addition, in consideration of recent development of a technique for performing a pixel vapor deposition process in a range where a temperature variation value is not large, the mask 100 may be made of a material such as nickel (Ni) or nickel cobalt (ni—co) having a thermal expansion coefficient slightly larger than the above. The thickness of the mask may be about 2 to 50 μm.

The frame 200 is formed in a form capable of attaching a plurality of masks 100. The frame 200 includes an outermost peripheral edge, and thus may include a plurality of corners formed in a first direction (e.g., a lateral direction), a second direction (e.g., a longitudinal direction). The plurality of corners may divide an area for attaching the mask 100 on the frame 200.

The frame 200 may generally include a tetragonal, tetragonal rim-shaped edge frame portion 210. The inside of the edge frame portion 210 may be hollow. That is, the edge frame portion 210 includes a hollow region R. The frame 200 is made of a metal material such as invar, super invar, aluminum, or titanium, and is preferably made of a material such as invar, super invar, nickel, or nickel cobalt having the same thermal expansion coefficient as that of the mask in consideration of thermal deformation, and the material is applicable to the edge frame portion 210 and the mask unit sheet portion 220, which are constituent elements of the frame 200.

Further, the frame 200 has a plurality of mask unit regions CR, and may include a mask unit sheet portion 220 connected to the edge frame portion 210. The mask unit sheet portion 220 is formed by electroforming as in the mask 100, or may be formed by a film forming process other than this. Further, 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 (sheet) by laser scribing, etching, or the like. Or the mask unit sheet portion 220 may form a plurality of mask unit regions CR by laser scribing, etching, or the like after the planar sheet is connected to the edge frame portion 210. The description will be given assuming that a plurality of mask unit regions CR are formed in the mask unit sheet portion 220 and then connected to the edge frame portion 210.

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 in the same sheet, and are integrally formed therebetween.

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

Further, the first grid sheet portion 223 may be formed to extend in the first direction (lateral direction). The first grid sheet portion 223 is formed in a straight line shape, and both ends thereof are connected to the edge sheet portion 221. When the mask unit sheet portion 220 includes a plurality of first grid sheet portions 223, the first grid sheet portions 223 are preferably formed at the same intervals therebetween.

Further, the second grid sheet portion 225 may be formed to extend in the second direction (longitudinal direction). The second grid sheet portion 225 is formed in a straight line shape, and both ends thereof are connected to the edge sheet portion 221. The first grid sheet portion 223 and the second grid sheet portion 225 vertically intersect each other. When the mask unit sheet portion 220 includes a plurality of second grid sheet portions 225, the second grid sheet portions 225 are preferably formed at the same intervals therebetween.

On the other hand, the interval between the first grid sheet portions 223 and the interval 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 thin film shapes, the cross-section perpendicular to the longitudinal direction may be rectangular, trapezoidal, rectangular (see fig. 5 b and 10), triangular, or the like, and the side and corner portions may be partially curved. The shape of the cross section can be adjusted during laser scribing, etching, etc.

The thickness of the edge frame portion 210 may be thicker than that of the mask unit sheet portion 220. The edge frame portion 210 is responsible for the overall rigidity of the frame 200, and thus may be formed to a thickness of several mm to several cm.

In the mask unit sheet portion 220, a process of manufacturing a thick sheet is substantially difficult, and when the thickness is too thick, a problem occurs in that a path of the organic material source 600 (see fig. 10) passing through the mask 100 is blocked in the OLED pixel vapor deposition process. On the contrary, when the thickness is too thin, it is difficult to secure rigidity for supporting the mask 100. Therefore, the mask unit sheet portion 220 preferably has a thickness thinner than that of the edge frame portion 210 but thicker than that of the mask 100. The thickness of the mask unit sheet portion 220 may be about 0.1 to 1 mm. Also, the widths of the first and second grid sheet portions 223 and 225 may be about 1 to 5mm.

In the planar sheet, a plurality of mask unit regions CR (CR 11 to CR 56) may be provided in addition to the regions occupied by the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225. From another point of view, the mask unit region CR may be a blank region other than the region occupied by the edge sheet portion 221, the first grid sheet portion 223, and the second grid sheet portion 225 in the hollow region R of the edge frame portion 210.

As the cells C of the mask 100 correspond to the mask cell regions CR, the cells C can be used as a path for evaporating pixels of the OLED through the mask pattern P. As described above, one mask unit C corresponds to one display of a smart phone or the like. One mask 100 may form a mask pattern P constituting one cell C. Or one mask 100 may have a plurality of cells C, each of which corresponds to each cell region CR of the frame 200, in order to accurately align the mask 100, however, a large area mask 100 should be avoided, and it is preferable to use a small area mask 100 having one cell C. Or one cell region CR of the frame 200 may correspond to one mask 100 having a plurality of cells C. In this case, in order to accurately align, it is considered that the mask 100 having about 2 to 3 small cells C corresponds.

The frame 200 has a plurality of mask unit regions CR, and each mask 100 can be attached in such a manner that each mask unit C corresponds to the mask unit region CR. Each mask 100 may include a mask cell C formed with a plurality of mask patterns P and a dummy portion (corresponding to a portion of the mask film 110 other than the cell C) around the mask cell C. The dummy portion may include only the mask film 110, or may include the mask film 110 formed with a predetermined dummy portion pattern having a similar form to the mask pattern P. The mask unit C corresponds to the mask unit region CR of the frame 200, and a part or all of the dummy portion may be attached to the frame 200 (mask unit sheet portion 220). Thus, the mask 100 and the frame 200 may form a unitary structure.

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

First, fig. 4 and 5 may provide the described frame 200. Fig. 6 is a schematic diagram showing a manufacturing process of the frame 200 according to an embodiment of the present invention.

Referring to fig. 6 (a), an edge frame portion 210 is provided. The edge frame portion 210 may have a quadrangular frame shape including a hollow region R.

Then, referring to fig. 6 (b), the mask unit sheet portion 220 is manufactured. The mask unit sheet portion 220 is manufactured by removing the mask unit region CR portion by laser scribing, etching, or the like after manufacturing a planar sheet using electroforming or other film forming processes. The present description will be made taking, as an example, the formation of the mask cell regions CR (CR 11 to CR 56) of 6×5. There may be 5 first grid sheet portions 223 and 4 second grid sheet portions 225.

Then, the mask unit sheet portion 220 may be corresponding to the edge frame portion 210. In the course of the correspondence, all sides of the mask unit sheet portion 220 may be stretched F1 to F4, and the edge sheet portion 221 may be brought into correspondence with the edge frame portion 210 in a state where the mask unit sheet portion 220 is flat. The mask unit sheet portion 220 may be stretched at a plurality of points (an example of points 1 to 3 in fig. 6 b) on one side. On the other hand, the F1, F2 mask unit sheet portion 220 may be stretched in one side direction instead of all sides.

Next, 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 welded W and attached. In order to firmly adhere the mask unit sheet portion 220 to the edge frame portion 220, it is preferable to weld W all sides. The welding W can minimize the space of the edge frame portion 210 and the mask unit sheet portion 220 by being performed only on the corner side closest to the edge frame portion 210 to the maximum extent, and thus the adhesion can be improved. The welded W portion may be formed in a linear shape or a dot shape, may have the same material as the mask unit sheet portion 220, and may serve as a medium for connecting the edge frame portion 210 and the mask unit sheet portion 220 together.

Fig. 7 is a schematic view showing a frame manufacturing process 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 attached to the edge frame portion 210, whereas in the embodiment of fig. 7, the mask unit region CR is formed after attaching the planar sheet to the edge frame portion 210.

First, as shown in fig. 6 (a), an edge frame portion 210 including a hollow region R is provided.

Then, referring to fig. 7 (a), a planar sheet (planar mask unit sheet portion 220') may be corresponding 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 been formed. In the process of performing the correspondence, all sides of the mask unit sheet portion 220 'are stretched F1 to F4, so that the mask unit sheet portion 220' can be made to correspond to the edge frame portion 210 in a flat state. The mask unit sheet portion 220' may be stretched at a plurality of points (an example of points 1 to 3 in fig. 7 a) on one side. On the other hand, the mask unit sheet portion 220' may be stretched in one side direction, but not all sides, to form the mask unit sheet portions F1 and F2.

Next, 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 welded W and attached. In order to firmly adhere the mask unit sheet portion 220' to the edge frame portion 220, it is preferable to weld W on all sides. The welding W can minimize the warpage space between the edge frame portion 210 and the mask unit sheet portion 220' only by being maximally close to the corner side of the edge frame portion 210, and thus can improve the adhesion. The welded W portion may be formed in a linear shape or a dot shape, and may have the same material as the mask unit sheet portion 220', and may serve as a medium for connecting the edge frame portion 210 and the mask unit sheet portion 220' together.

Next, referring to fig. 7 (b), a mask unit region CR is formed on the planar sheet (planar mask unit sheet portion 220'). The sheet material of the mask unit region CR portion may be removed by laser scribing, etching, or the like, thereby forming the mask unit region CR. The present description will be made taking, as an example, the formation of the mask cell regions CR (CR 11 to CR 56) of 6×5. If the mask unit region CR is formed, a portion welded W to the edge frame portion 210 becomes an edge sheet portion 221, and a mask unit sheet portion 220 having 5 first grid sheet portions 223 and 4 second grid sheet portions 225 may be formed.

On the other hand, although fig. 6 and 7 illustrate an embodiment in which the edge frame portion 210 and the mask unit sheet portion 220 are bonded by welding W, the bonding is not necessarily limited thereto, and may be performed by a method using a eutectic (electro) bonding portion EM, an electroforming portion 150, other organic/inorganic adhesive, and the like, as illustrated in fig. 10.

Fig. 8 is a schematic view showing a stretched form of the mask 100 (fig. 8 (a)) and a state of the mask 100 corresponding to the cell region CR of the frame 200 (fig. 8 (b)) according to an embodiment of the present invention.

Then, a mask 100 formed with a plurality of mask patterns P is provided. The mask 100 of invar, super invar material can be manufactured electroformed, as previously described, with one cell C formed on the mask 100.

A conductive material is used as a master (mother plate) used as a cathode (cathode) in electroforming. As the conductive material, a metal oxide may be formed on the surface of the metal, impurities may flow in during the production of the metal, inclusions or Grain boundaries (Grain boundaries) may be present in the polysilicon base material, and the conductive polymer base material may have a high possibility of containing impurities, and is fragile in strength, acid resistance, and the like. Elements such as metal oxides, impurities, inclusions, grain boundaries, and the like, which prevent the formation of a uniform electric field on the surface of the mother substrate (or cathode), are called "defects". A uniform electric field cannot be applied to the cathode of the material due to the defect, so that a part of the plating film (mask 100) is unevenly formed.

In the process of realizing ultra-high quality pixels of UHD level or more, the formation of pixels is adversely affected by the unevenness of the plating film and the plating film pattern (mask pattern P). The pattern width of the FMM or shadow mask can be formed in a size of several to several tens of μm, preferably in a size of less than 30 μm, and even a defect of several μm occupies a large specific gravity in the pattern size of the mask.

In addition, in order to remove defects in the cathode of the above-mentioned materials, an additional process for removing metal oxides, impurities, etc. is performed, but other defects such as etching of the cathode body material may be induced in the process.

Thus, the present invention may use a master (or cathode) of monocrystalline silicon material. For conductivity, a high concentration doping (dopping) of 10 ¹⁹/cm³ or more may be performed on the master of the single crystal silicon material. Doping may be performed on the entire motherboard or only on a surface portion of the motherboard.

In the case of doped single crystal silicon, since it has no defect, a uniform electric field is formed over the entire surface during electroforming, and thus a uniform plating film (mask 100) can be generated. The frame-integrated masks 100, 200 manufactured by uniform plating can further improve the image quality level of the OLED pixels. In addition, since a new process for removing and eliminating defects is not required, the method has the advantages of reducing the process cost and improving the production efficiency.

Further, by using a master of silicon material, there are the following advantages: the insulating portion can be formed by oxidizing (Oxidation) and nitriding (Nitridation) the surface of the motherboard as needed. The insulating portion may be formed by a photoresist. The portion where the insulating portion is formed can prevent electrodeposition of the electrodeposition coating film (mask 100), so that a pattern (mask pattern P) can be formed on the coating film.

The width of the mask pattern P may be less than 40 μm and the thickness of the mask 100 may be about 2 to 50 μm. Since the frame 200 has a plurality of mask unit regions CR (CR 11 to CR 56), there are also a plurality of masks 100, and the masks 100 have mask units C (C11 to C56) corresponding to the respective mask unit regions CR (CR 11 to CR 56).

Referring to fig. 8 (a), the mask 100 may be corresponding to one mask unit region CR of the frame 200. As shown in fig. 8 (a), in the course of the correspondence, the mask 100 is stretched at both sides in the one axial direction of the mask 100 to correspond the mask cells C to the mask cell regions CR in a flat state. The mask 100 may be stretched at a plurality of points (1 to 3 points in fig. 8, for example) on one side. In addition, all sides of F1-F4 mask 100 may be stretched in all axial directions instead of one.

For example, the tensile force applied to each side of the mask 100 may also be not more than 4N. The tensile force applied may be the same or different depending on the size of the mask 100. In other words, the mask 100 of the present invention is of a size including one mask cell C, and thus the required stretching force may be the same or at least reduced compared to the existing stick-type mask 10 including a plurality of cells C1 to C6. Considering that 9.8N means a force equivalent to a gravity of 1kg, since 1N is a force of less than 400g, even if the mask 100 is attached to the frame 200 after being stretched, the tension (tension) applied to the frame 200 by the mask 100 or the tension applied to the mask 100 by the frame 200 in the opposite direction becomes very small. Thereby, deformation of the mask 100 and/or the frame 200 due to the tension is minimized, so that alignment errors of the mask 100 (or the mask pattern P) can be minimized.

Further, the conventional mask 10 of fig. 1 includes 6 cells C1 to C6 and thus has a long length, whereas the mask 100 of the present invention includes one cell C and has a short length and thus the degree of deviation of the pixel position accuracy becomes small. For example, assuming that the length of the mask 10 including a plurality of cells (C1 to C6.) is 1m, and a pixel position accuracy error of 10 μm will occur for 1m as a whole, the mask 100 of the present invention becomes 1/n in the error range due to the relative length reduction (reduction corresponding to the reduction of the number of cells C). For example, assuming that the length of the mask 100 of the present invention is 100mm, there is a reduction in length from 1m length to 1/10 of the length of the existing mask 10, and thus a pixel position accuracy error of 1 μm is generated for the whole of the 100mm length, thereby having an effect of significantly reducing the alignment error.

On the other hand, the mask 100 has a plurality of cells C, and even if each cell C corresponds to each cell region CR of the frame 200, the mask 100 may correspond to a plurality of mask cell regions CR of the frame 200 if the alignment error is still within a minimized range. Or the mask 100 having a plurality of cells C may correspond to one mask cell region CR. Even in this case, the mask 100 preferably has as few cells C as possible in consideration of the process time and production efficiency due to alignment.

In order to make the mask 100 correspond to the mask cell region CR in a flat state, the alignment state can be confirmed in real time by a microscope while adjusting the tensile forces F1 to F4. In the present invention, since only one cell C of the mask 100 is required to be aligned and checked, the present invention can significantly shorten the manufacturing time compared to the conventional method (see fig. 2) in which a plurality of cells C (C1 to C6) must be simultaneously aligned and checked.

That is, the manufacturing method of the frame-integrated mask of the present invention can greatly shorten the time as compared with the conventional method in which 6 processes of associating each of the cells C11 to C16 in the 6 masks 100 with one of the cell regions CR11 to CR16 and confirming the alignment state respectively are required to simultaneously associate 6 of the cells C1 to C6 and confirm the alignment state of 6 of the cells C1 to C6 simultaneously.

In the method for manufacturing a frame-integrated mask according to the present invention, the product yield in the process of aligning 30 masks 100 corresponding to 30 cell areas CR (CR 11 to CR 56) for 30 times is significantly higher than that in the conventional 5-time process of aligning 5 masks 10 (see fig. 2 a) each including 6 cells (C1 to C6) corresponding to the frame 20. The existing method of aligning 6 cells (C1 to C6) in a region corresponding to 6 cells C at a time is a very complicated and difficult operation, and thus shows low product yield.

On the other hand, after the mask 100 is mapped to the frame 200, the mask 100 may be temporarily fixed to the frame 200 by a predetermined adhesive. After that, the pasting step of the mask 100 is performed.

Fig. 9 is a schematic view showing a process of corresponding the mask 100 to the cell region CR of the frame 200 and pasting according to an embodiment of the present invention. Fig. 10 is a sectional view of B-B' of fig. 9, and is a partially enlarged sectional view showing a state in which the mask 100 is attached to the frame 200 (the first grid sheet portion 223) according to various embodiments of the present invention.

Next, referring to fig. 9, 10 (a) and (b), a part or all of the edge of the mask 100 may be adhered to the frame 200. The bonding may be performed by welding W, preferably by laser welding W. The welding W portion may have the same material as the mask 100/frame 200 and may be integrally connected.

When laser light is irradiated to an upper portion of an edge frame portion (or dummy portion) of the mask 100, a portion of the mask 100 may be melted and welded W with the frame 200. The welding W is performed only to be maximally close to the corner side of the frame 200, so that the warpage space between the mask 100 and the frame 200 can be maximally reduced, and the adhesion can be improved. The solder W is formed in a line or a dot shape and has the same material as the mask 100, and serves as a medium for integrally connecting the mask 100 and the frame 200.

A frame of two adjacent masks 100 is adhered W to the upper surface of the first grid sheet portion 223 (or the second grid sheet portion 225), respectively. The width and thickness of the first grid sheet portion 223 (or the second grid sheet portion 225) can be formed in a size of about 1 to 5mm, and in order to improve the production efficiency of the product, the width of the first grid sheet portion 223 (or the second grid sheet portion 225) overlapping the edge of the mask 100 should be reduced to about 0.1 to 2.5mm to the maximum extent.

The cross-sectional shapes of the first and second grid sheet portions 223, 225 perpendicular to the longitudinal direction may be quadrangle, trapezoid, or the like having a low height.

The welding W method is only one of methods of adhering the mask 100 to the frame 200, and the adhering method is not limited to these embodiments.

Description of other examples as shown in fig. 10 (c), the mask 100 may be attached to the frame 200 using an attachment portion EM of a eutectic material. The adhesion part EM of the eutectic material may have various shapes such as a film, a wire, and a bundle, and may have a thickness of about 10 to 30 μm as an adhesive agent containing at least two metals. For example, the adhesion part EM of the eutectic material may include at least one metal selected from the group consisting of In, sn, bi, au and Sn, bi, ag, zn, cu, sb, ge. The adhesion part EM of the eutectic material includes at least two metal solid phases (solid phases), and at a eutectic point (eutectic point) of a specific temperature/pressure, both the metal solid phases may be changed to liquid phases (liquid phases). Furthermore, if the eutectic point is separated, the two metal solid phases can be formed again. Therefore, the phase change from solid phase to liquid phase to solid phase acts as an adhesive.

Unlike a general organic adhesive, the eutectic bonding part EM does not contain any volatile organic matter. Therefore, the organic matters in the adhesive react with the process gas to prevent the pixel of the OLED from being adversely affected, or the organic matters contained in the adhesive itself and other external gases pollute the pixel process chamber or are deposited as impurities on the OLED pixel. Further, since the eutectic bonding part EM is solid, it cannot be cleaned with an OLED organic detergent, and has corrosion resistance. Further, since two or more metals are contained, it is possible to connect with the mask 100 and the frame 200 of the same metal material with high adhesion as compared with an organic adhesive, and since it is a metal material, there is an advantage in that it has a low possibility of deformation.

Further describing another example, as shown in (d) of fig. 10, the mask 100 may be attached to the frame 200 by further forming the attaching plating part 150 of the same material as the mask 100. After the mask 100 is mapped to the frame 200, an insulating portion such as PR may be formed in the lower surface direction of the mask 100. The plating portion 150 may be electrodeposited and adhered on the frame 200 and the rear surface of the mask 100 where the insulating portion is not covered and is exposed.

The adhesion plating part 150 may be an intermediary for integrating the mask 100 and the frame 200 while being electrodeposited on the exposed surface of the mask 100 and the frame 200. At this time, the adhesion plating part 150 is connected to the edge portion of the mask 100 and electrodeposited, and thus has a state in which a tensile force is applied in the inside or outside direction of the frame 200, and can support the mask 100. Accordingly, the mask 100 pulled toward the side of the frame 200 and tightened can be integrated with the frame 200 without an additional process of stretching and aligning the mask.

In fig. 10, for convenience of explanation, the thickness and width of the solder W portion and the bonding portion EM of the eutectic material are shown somewhat exaggerated, and in reality, the portion is a portion which has little protrusion and is connected to the frame 200 in a state of being included in the mask 100.

Then, if the process of attaching one mask 100 to the frame 200 is finished, the process of sequentially corresponding the remaining mask 100 to the remaining mask units C and attaching the same to the frame 200 may be repeated. Since the mask 100, which has been attached to the frame 200, can provide the reference position, there is an advantage in that the time can be significantly shortened in sequentially corresponding the remaining mask 100 to the cell region CR and confirming the alignment state. Moreover, the method has the following advantages: the accuracy of the pixel position between the mask 100 attached to one mask unit region and the mask 100 attached to the mask unit region adjacent thereto is not more than 3 μm, so that a mask for forming an ultra-high image quality OLED pixel with accurate alignment can be provided.

Fig. 11 is a schematic diagram showing an OLED pixel vapor deposition apparatus 1000 using the frame-integrated masks 100, 200 according to an embodiment of the present invention.

Referring to fig. 11, the oled pixel vapor deposition device 1000 includes: a magnetic plate 300 which accommodates the magnet 310 and is provided with a cooling water pipe 350; and a vapor deposition source supply unit 500 for supplying the organic material source 600 from the lower portion of the magnetic plate 300.

A target substrate 900 such as glass for depositing the organic material source 600 may be interposed between the magnetic plate 300 and the deposition source supply unit 500. The frame-integrated masks 100, 200 (or FMMs) are closely or very closely arranged on the object substrate 900, and the frame-integrated masks 100, 200 (or FMMs) vapor-deposit the organic material source 600 pixel by pixel, respectively. The magnet 310 generates a magnetic field, and is closely attached to the target substrate 900 by the magnetic field.

The vapor deposition source supply unit 500 may reciprocate in the left-right path to supply the organic material source 600, and the organic material source 600 supplied from the vapor deposition source supply unit 500 may be deposited on one side of the target substrate 900 by the pattern P formed on the frame-integrated mask 100, 200. The organic matter source 600 evaporated through the pattern P of the frame-integrated mask 100, 200 may function as the pixel 700 of the OLED.

In order to prevent uneven evaporation of the pixel 700 due to Shadow Effect (Shadow Effect), the patterns of the frame-integrated masks 100, 200 may be obliquely formed S (or formed in a tapered shape S). The organic source 600 passing through the pattern along the inclined surface and in the diagonal direction may also contribute to the formation of the pixel 700, and thus the pixel 700 may be evaporated with a uniform thickness as a whole.

As described above, the present invention has been illustrated and described in terms of the preferred embodiments, but the present invention is not limited to the above-described embodiments, and various modifications and changes can be made by those skilled in the art without departing from the spirit of the present invention. Such modifications and variations are intended to fall within the scope of the invention and the appended claims.

Claims

1. A frame-integrated mask is formed integrally with a frame for supporting the mask by a plurality of masks, wherein,

The frame comprises:

an edge frame portion including a hollow region; and

A mask unit sheet portion having a plurality of mask unit regions along at least one of a first direction and a second direction perpendicular to the first direction, and connected to the edge frame portion,

The mask unit sheet portion includes:

An edge sheet portion;

At least one first grid sheet portion formed extending in the first direction and connected at both ends to the edge sheet portion; and

At least one second grid sheet portion extending in a second direction perpendicular to the first direction and intersecting the first grid sheet portion, and connected at both ends to the edge sheet portion,

Each mask is attached to an upper portion of the mask unit sheet portion,

The mask, the mask unit sheet part and the edge frame part are made of any one of invar alloy, super invar alloy, nickel and nickel cobalt, and the mask, the mask unit sheet part and the edge frame part are made of the same material,

The mask unit sheet portion and the edge frame portion are integrally connected by a welding medium of the same material as that generated during welding, and the mask unit sheet portion are integrally connected by a welding medium of the same material as that generated during welding.

2. The frame-integrated mask of claim 1, wherein,

Each mask corresponds to each mask unit region.

3. The frame-integrated mask of claim 1, wherein,

The mask includes a mask unit formed with a plurality of mask patterns and a dummy portion located at a periphery of the mask unit,

At least a part of the dummy portion is connected to the mask unit sheet portion.

4. The frame-integrated mask of claim 1, wherein,

The mask includes one mask unit, each mask corresponding to each mask unit region of the mask unit sheet portion.

5. The frame-integrated mask of claim 1, wherein,

The mask includes a plurality of mask units, each mask corresponding to each mask unit region of the mask unit sheet portion.

6. The frame-integrated mask of claim 1, wherein,

The edge frame part is in a quadrangle shape.

7. The frame-integrated mask of claim 1, wherein,

The thickness of the edge frame portion is thicker than the thickness of the mask unit sheet portion, and the thickness of the mask unit sheet portion is thicker than the thickness of the mask.

8. The frame-integrated mask of claim 1, wherein,

The pixel position accuracy between the mask stuck on one mask unit region and the mask stuck on the adjacent mask unit region is not more than 3 μm.

9. A method of manufacturing a frame-integrated mask formed integrally of a plurality of masks and a frame for supporting the masks, wherein the method comprises the steps of:

(a) Preparing a frame in which a mask unit sheet portion has a plurality of mask unit regions along at least one of a first direction and a second direction perpendicular to the first direction, and is connected to an edge frame portion;

(b) Corresponding the mask to one mask unit region of the mask unit sheet portion; and

(C) At least a portion of the edge of the mask is connected to the mask unit sheet portion,

Wherein the mask unit sheet portion includes:

An edge sheet portion;

The mask, the mask unit sheet part and the edge frame part are made of any one material of invar alloy, super invar alloy, nickel and nickel cobalt, and the mask, the mask unit sheet part and the edge frame part are made of the same material,