Method for manufacturing deposition mask frame assembly for display panel

Abstract

The present invention relates to a method for manufacturing a deposition mask frame assembly. More specifically, a supporting mask strip and a slit mask strip are arranged on the frame and welded to the frame. The deposition mask strip is stretched in the X-axis direction along the length direction and adhered and stretched in the Y-axis direction. The frame of the deposition mask strip is welded to the frame to form an integral whole to prevent wrinkles on the deposition mask due to stretching, thereby manufacturing a precise and high-quality deposition mask frame assembly.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a deposition mask frame assembly for a display panel, and more particularly, to a technology for manufacturing a mask frame assembly by stretching and welding a mask. Background Art

[0002] Among display devices, OLED display panels using organic light emitting diodes have advantages of wide viewing angle, excellent contrast, and fast response speed. Therefore, the application fields of organic light emitting diodes (OLEDs) are gradually expanding.

[0003] The intermediate layers including the electrodes and the light emitting layer of such an organic light emitting diode (OLED) can be formed by various methods, one of which is a deposition method.

[0004] In order to manufacture small and medium-sized OLED display panels, the deposition process of organic and inorganic substances is carried out in the OLED manufacturing process to produce RGB pixels. That is, the fine metal mask (FMM) has the same pattern as the image of the thin film to be formed on the TFT glass (Thinfilm transistor glass), and the raw materials of the thin film are deposited by aligning the position of the fine metal mask to form a thin film of the desired pattern. This deposition process adopts a method of heating the organic matter in the deposition source located at the bottom of the chamber, and sublimating the heated organic matter through the mask located at the top to deposit on the TFT glass.

[0005] This fine metal mask (FMM) has a strip shape as a whole, so it is also called a deposition mask strip. Generally, one end and the other end of the deposition mask strip are stretched at the same time, and the deposition mask strip is laser welded to the mask frame, thereby manufacturing a deposition mask frame assembly.

[0006] Deposition mask strips can be used to mass-produce display panels, and are therefore widely used in the manufacture of deposition mask frame assemblies. Deposition mask frame assemblies are used to produce relatively small display panels such as smartphones. However, there is a need to develop mask strip frame assemblies that can be suitable for medium to large-sized display panels such as tablet PCs or laptops.

[0007] Figure 1 is a diagram illustrating deposition of mask strips. Figure 1 (a) is a diagram showing the top of a deposited mask strip; Figure 1 (b) shows Figure 1 (a) is a diagram of the cross section taken along the line AA'.

[0008] like Figure 1As shown in (a), a deposition mask bar 100, generally referred to as a fine metal mask (FMM), includes a structural mask bar 110 and a plurality of unit masks 120, and extends in a length direction.

[0009] The structural mask strip 110 is composed of a frame 111 and ribs 112, and a plurality of single-unit masks 120 are formed with a plurality of deposition pattern holes P. A plurality of single-unit masks may exist in one structural mask strip 110. Hundreds of thousands to millions of deposition pattern holes P may be formed in one single-unit mask. A plurality of skirts 113 are symmetrically arranged at one end and the other end of the frame 111, which may function as clamping areas. The clamp (not shown) clamping the skirt may easily perform stretching (Tx) along the length direction in the X-axis direction. A clamp is arranged on each skirt for clamping, such as Figure 1 As shown in (a), in the case of 8 skirts, 8 clamps perform stretching simultaneously.

[0010] The structural mask strip 110 may have a thickness of 100 μm to 200 μm, a length of more than 1 m, and a width of several tens of cm, and the unit mask 120 may have a thickness of 10 μm to 20 μm. The unit mask 120 and the structural mask strip 110 may be seamlessly integrated, or may be manufactured separately and combined by welding, so there is a seam.

[0011] In addition, the structural mask strip 110 further includes ribs 112 , which are regions disposed between the unit mask 120 and the unit mask 120 and where no deposition pattern holes are formed.

[0012] However, when a large deposition mask strip is stretched simultaneously by multiple clamps as described above, the tensile force cannot be uniformly applied to the deposition mask strip, so wrinkles appear, and at the same time, there is a problem of shrinkage in the Y-axis direction (arrow direction). For example, there are four skirts at one end, so if it is clamped by four clamps, three wrinkles W1, W2, and W3 may appear as shown in the figure. In terms of shrinkage force, the shrinkage force in the middle area of ​​the deposition mask strip is greater than that in the end area, so the size and depth of the wrinkles are also greater in the middle area of ​​the deposition mask strip.

[0013] In addition, the larger the side of the deposition mask strip, the longer and heavier the ribs become in the Y-axis direction, so the ribs sink due to gravity.

[0014] like Figure 1 As shown in (b), the deposition mask strip shrinks in the Y-axis direction (arrow direction) and generates three wrinkles W1, W2, and W3, thereby increasing the shadow phenomenon and causing the quality of the deposition mask frame assembly to decrease.

[0015] Furthermore, the larger the size of the deposition mask strip, the more the number of stretched clamps is, so the number of wrinkles increases, further aggravating the problem of quality degradation.

[0016] The Korean Patent Gazette (Authorization Announcement No.: 10-2193044; "Metal Mask Manufacturing System and Method") discloses a technology for stretching the edges of more than two sides of a single mask by multiple clamps and fixing it to the mask frame in a flattened state, but does not disclose a method for adhering and stretching in the Y-axis direction to prevent wrinkles on the strip-type mask. Summary of the invention

[0017] (Problem to be solved)

[0018] The invention relates to a method for manufacturing a deposition mask frame assembly, the purpose of which is to prevent wrinkles from occurring on medium-to-large deposition masks due to stretching, thereby manufacturing a precise and high-quality deposition mask frame assembly.

[0019] (Methods of solving the problem)

[0020] To achieve this purpose, according to one aspect, a deposition mask frame assembly manufacturing method is provided, wherein the deposition mask frame assembly is manufactured using a deposition mask strip, wherein the deposition mask strip is composed of a structural mask strip and a plurality of monomer unit masks, wherein the structural mask strip has a frame and ribs, and the monomer unit mask is formed with a plurality of deposition pattern holes, comprising the following steps:

[0021] Disposing a frame having a quadrilateral shape in which a hollow portion is formed;

[0022] A supporting mask strip is arranged on the frame, and the supporting mask strip is welded to the frame in a state where the supporting mask strip is stretched in a Y-axis direction along a length direction;

[0023] A slit mask strip is arranged on the frame, and the slit mask strip is welded to the frame in a state where the slit mask strip is stretched along the length direction in the X-axis direction; and

[0024] The deposition mask strip is arranged on the frame, and the deposition mask strip is stretched along the length direction in the X-axis direction, and the frame is welded to the frame in the Y-axis direction in a stretched state. Therefore, wrinkles due to stretching are prevented, and a precise and high-quality deposition mask frame assembly can be manufactured.

[0025] (Effects of the Invention)

[0026] The present invention is to prevent wrinkles from occurring in medium and large deposition mask strips due to stretching, thereby manufacturing a precise and high-quality deposition mask frame assembly.

[0027] In addition, the deposition mask frame assembly is manufactured using the support mask bars and the slit mask bars, thereby stably fixing the deposition mask and covering the gaps between the deposition masks.

[0028] In addition, there is no need to additionally form a skirt on the deposition mask strip, and the deposition mask strip can be prevented from being damaged.

[0029] In addition, since laser welding is performed underneath, warping and even gaps between the TFT glass and the single unit mask can be prevented during the deposition process. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a diagram illustrating deposition of mask strips.

[0031] Figure 2 FIG. 1 is a diagram illustrating a method of manufacturing a deposition mask frame assembly according to an embodiment.

[0032] Figure 3 FIG. 1 is a diagram illustrating a method for welding a supporting mask strip on a frame according to an embodiment.

[0033] Figure 4 FIG. 1 is a diagram illustrating a method for welding a slit mask strip on a frame according to an embodiment.

[0034] Figure 5 FIG. 1 is a diagram illustrating a method for depositing a mask strip on a frame configuration according to an embodiment.

[0035] Figure 6 FIG. 1 is a diagram illustrating a method of stretching a deposition mask strip according to an embodiment.

[0036] Figure 7 FIG. 2 is a diagram illustrating a method of welding overlapped regions according to an embodiment.

[0037] Figure 8 FIG. 1 is a diagram illustrating a method for welding an overlapping area of ​​a deposition mask strip, a slit mask strip, and a support mask strip according to another embodiment.

[0038] Fig. 9 Yes Description Figure 8 A diagram of an embodiment of a support mask strip opening.

[0039] Fig.10 is a diagram showing a deposition mask frame assembly after welding is completed.

[0040] Fig.11 is a diagram showing a trimmed deposition reticle frame assembly.

[0041] Fig.12 It is shown in Fig.11A diagram of a deposition mask frame assembly in which no monomer unit mask is adhered.

[0042] Fig.13 It is explained in Fig.12 A diagram of a method of welding a single unit mask on a mask strip structure.

[0043] (Explanation of Reference Numerals)

[0044] 100: Deposition of mask strips

[0045] 110: Structural mask strips

[0046] 111: Border

[0047] 112: Ribs

[0048] 113: Skirt

[0049] 120: Single unit mask

[0050] 200: Framework

[0051] 300: Support mask strips

[0052] 400: Slit mask strip

[0053] 1000: Deposition mask frame assembly

[0054] 2000: Adhesion stretcher DETAILED DESCRIPTION

[0055] Below, a detailed description is given so that those skilled in the art can easily understand and implement the present invention by referring to the preferred embodiments described in the accompanying drawings. When describing the present invention, if it is judged that the specific description of the relevant known functions or structures may unnecessarily make the key points of the embodiments of the present invention unclear, the detailed description will be omitted. In the present invention, the terms used in the full text of the specification are defined as terms taking into account the functions in the embodiments of the present invention, and are terms that can be fully deformed according to the intentions, conventions, etc. of the users or operators, so the definitions of these terms should be defined based on the content of the full text of this specification.

[0056] In addition, one aspect of the above and additional inventions may become apparent from the embodiments described below. It is understood that the structure of an aspect or an embodiment selectively described in this specification is that, although shown as a single integrated structure in the drawings, it is freely combinable with each other unless it is obvious to a person skilled in the art that there is a technical contradiction.

[0057] Therefore, the embodiments described in this specification and the structures shown in the drawings are only the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, it should be understood that there may be various equivalents and modifications that can be replaced at the time of this application.

[0058] Figure 2 1 is a diagram illustrating a method for manufacturing a deposition mask frame assembly according to an embodiment. As shown in the figure, the method for manufacturing a deposition mask frame assembly using a deposition mask strip includes the following steps, wherein the deposition mask strip is composed of a structural mask strip and a plurality of unit masks, wherein the structural mask strip has a frame and ribs, and the plurality of unit masks are formed with a plurality of deposition pattern holes. That is, the deposition mask frame assembly manufacturing method includes: step S100, configuring a frame having a quadrilateral shape with a hollow portion; step S200, configuring a supporting mask strip on the frame, wherein the supporting mask strip is welded to the frame in a state of being stretched in the Y-axis direction along the length direction; step S300, configuring a slit mask strip on the frame, wherein the slit mask strip is welded to the frame in a state of being stretched in the X-axis direction along the length direction; and step S400, configuring a deposition mask strip on the frame, wherein the frame is welded to the frame in a state of being stretched in the Y-axis direction while the deposition mask strip is stretched in the X-axis direction along the length direction.

[0059] Figure 3 1 is a diagram illustrating a method for welding a support mask strip on a frame according to an embodiment. As shown in the figure, a frame 200 is configured. The frame 200 may have a quadrilateral shape with a hollow portion formed therein. The frame 200 may be a right-angled quadrilateral shape and may be composed of a long side and a short side. A support mask strip 300 is configured on the frame, and the support mask strip may be welded to the frame in a state where it is stretched in the Y-axis direction along the longitudinal direction (Longitudinal). There may be at least two support mask strips 300, which may be welded to the short side of the frame 200 in a flat state by applying a tensile force of Ty through a clamp. The support mask strip 300 supports other mask strips located above the support mask strip, and may prevent the other mask strips from sinking. The welding may be optical welding, in particular, laser beam welding, and the welding may be performed by irradiating a laser beam on the support mask strip.

[0060] Figure 4 1 is a diagram illustrating a method for welding a slit mask strip on a frame according to an embodiment. As shown in the figure, a slit mask strip 400 is arranged on the frame, and the slit mask strip can be welded to the frame 200 in a state where it is stretched along the length direction in the X-axis direction. There can be at least two slit mask strips 400, and a tensile force of Tx is applied, and the slit mask strips can be welded to the long side of the frame 200 in a flat state. Welding can be performed by irradiating the slit mask strip with a laser.

[0061] The width of the slit mask strip can be smaller than the width of the supporting mask strip, and the length can be even smaller than the supporting mask strip. The slit mask strip and the supporting mask strip can form skirts, but they are not formed as shown, so they can be clamped by a clamp at one end. The slit mask strip and the supporting mask strip can be stretched in two directions by respective clamps.

[0062] According to an embodiment, the deposition mask frame assembly manufacturing method may further include a step of welding the overlapping area of ​​the support mask bar 300 and the slit mask bar 400 to fix the slit mask bar on the support mask bar. Therefore, the slit mask bar can be closely held on the support mask bar.

[0063] Figure 5 2 is a diagram illustrating a method for configuring a deposition mask strip on a frame according to an embodiment. As shown in the figure, a deposition mask strip 100 is configured on a frame 200. The deposition mask strip 100 can be configured so that the rib 112 is located on the support mask strip 300 based on the X axis, and the frame 111 is located on the frame 200 or the slit mask strip 400 based on the Y axis. In this configuration, a region WZ 1 where the rib 112 overlaps with the support mask strip 300 is formed, and a region WZ 2 where the support mask strip 300, the slit mask strip 400, and the frame 111 overlap is formed. WZ 1 and WZ 2 can perform the function of a welding region.

[0064] As shown in the figure, the slit mask strip 400 may be disposed on the upper part or the lower part of the deposition mask strip 100. In order to be disposed on the lower part, the welding of the slit mask strip 400 may be performed after the welding of the deposition mask strip 100.

[0065] Figure 6 FIG. 1 is a diagram illustrating a method of stretching a deposition mask strip according to an embodiment. Figure 6 (a) is a top view showing a stretched deposition mask strip; Figure 6 (b) shows Figure 6 (a) is a diagram of the cross section taken along the line AA'.

[0066] like Figure 6 As shown in (a), a tensile force Tx is applied to the deposition mask strip along the length direction in the X-axis direction, and an adhesion tensile force Ty can be applied in the Y-axis direction. Preferably, Ty is less than Tx (Ty <Tx)。

[0067] The adhesion stretching may be performed by stretching in the Y-axis direction while adhering the frame area TZ1 located at the corner and the frame area TZ2 adjacent to the rib. Figure 6 As shown in (b), no wrinkles are generated at the ribs 112 where wrinkles are easily generated, and the shape and position of the pattern holes of the single unit mask can be retained.

[0068] The adhesion stretching can be performed by vacuum or electrostatic means. Therefore, there is no need to form an additional skirt on the frame 111, and no clamp is used for stretching, which has the advantage of preventing the deposition mask strip from being damaged. For adhesion stretching, an additional adhesion stretcher 2000 can be introduced.

[0069] The frame 111 may include a skirt 113. The skirt 113 is a region for the clamp to clamp, and is not an essential component.

[0070] Figure 7 FIG. 2 is a diagram illustrating a method of welding overlapped regions according to an embodiment. Figure 7 (a) is a diagram illustrating a method of welding the overlapping area WZ1 of the deposition mask strip 100 and the support mask strip 300, Figure 7 (b) is a diagram for explaining a method of welding the overlapping area WZ2 of the deposition mask strip 100 , the slit mask strip 400 , and the support mask strip 300 .

[0071] like Figure 7 As shown in (a), the method for manufacturing a deposition mask frame assembly may further include positioning the rib 112 of the deposition mask bar 100 on the supporting mask bar 300, welding the area WZ1 (dashed line) where the rib overlaps with the supporting mask bar, and welding the deposition mask bar to the supporting mask bar. The rib and the supporting mask bar are melted at the joint J to be fixed to each other.

[0072] Furthermore, the laser is irradiated on the bottom of the support mask strip, and the area WZ1 where the rib and the support mask strip overlap can be welded. Therefore, a burr (welding protrusion) can be generated on the bottom of the support mask strip 300.

[0073] In addition, if Figure 7 As shown in (b), the deposition mask frame assembly manufacturing method may also include the step of positioning a portion of the frame area on the slit mask strip to weld the overlapping area WZ 2 (dashed line) of the frame 111 of the support mask strip 300, the slit mask strip 400, and the deposition mask strip 100. The welding may be performed by laser, wherein the laser is irradiated on the bottom of the support mask strip to join the slit mask strip and the support mask strip at the joint point J1, and the laser is irradiated on the top of the deposition mask strip to join the slit mask strip and the deposition mask strip, and the slit mask strip and the deposition mask strip may be melted and joined at the joint point J2. Therefore, burrs are generated on the top of the deposition mask strip and the bottom of the support mask strip, respectively. The top of the deposition mask strip is the surface that is in close contact with the TFT glass during the deposition process.

[0074] Figure 8 FIG. 1 is a diagram illustrating a method for welding an overlapping area of ​​a deposition mask strip, a slit mask strip, and a support mask strip according to another embodiment. Figure 8 As an improvement Figure 7 An embodiment of the problem of embodiment (b) is related to preventing burrs from being generated on top of deposited mask stripes.

[0075] In the deposition mask frame assembly manufacturing method, the support mask strip has an opening, and the laser is irradiated on the lower opening of the support mask strip and the area outside the lower opening, so that the support mask strip, the slit mask strip and the overlapping area WZ 2 of the frame can be welded. Therefore, burrs are only generated on the lower sides of the support mask strip and the slit mask strip, and the TFT glass and the hybrid mask strip are closely attached when they are in close contact during the deposition process, and no gap will appear, thereby reducing the shadow effect.

[0076] According to one embodiment, in order to weld the overlapping area of ​​the deposition mask strip, the slit mask strip and the support mask strip, the rod can push the bottom of the support mask strip up to a predetermined height, thereby temporarily clinging to the deposition mask strip, the slit mask strip and the support mask strip to achieve close welding.

[0077] Fig. 9 Yes Description Figure 8 FIG. 3 is a diagram of an opening of a support mask strip of an embodiment of the present invention. As shown in the figure, the support mask strip 300 may have a through opening. Therefore, it is possible to perform Figure 8 A plurality of openings may be formed, and may be formed in the region WZ2 where the support mask strip, the slit mask strip, and the frame overlap.

[0078] Fig.10 is a diagram showing a deposition mask frame assembly after welding. Figure 4 , Figure 7 , Figure 8 The embodiment of the invention welds the support mask strip 300, the slit mask strip 400 and the deposition mask strip 100, thereby manufacturing a component in which each mask strip is integrated with the frame. Figure 7 The area WZ1 (dashed line) where the welding ribs overlap with the supporting mask strips in the embodiment (a) is as follows Figure 8 The embodiment of the welding support mask strip 300, the slit mask strip 400 and the deposition mask strip 100 overlap the border 111 of the region WZ2 (dashed line).

[0079] The deposition mask strips 100 are welded at intervals to have a length of about L, thereby avoiding interference between the deposition mask strips. The problem of organic matter leakage during deposition due to the formation of intervals can be avoided by the slit mask strips 400.

[0080] Fig.111 is a diagram showing a trimmed deposition mask frame assembly. As shown in the figure, the method for manufacturing the deposition mask frame assembly 1000 may further include the step of cutting or even trimming a portion of the support mask bar 300, the slit mask bar 400, and the deposition mask bar 100 located outside the frame 200. The deposition mask frame assembly 1000 may be completed by cutting.

[0081] In order to perform a deposition process using the deposition mask frame assembly 1000 , a TFT glass (not shown) is closely attached to the hollow region of the frame 200 , an organic source is disposed at the bottom of the deposition mask frame assembly 1000 , and deposition can be performed.

[0082] Fig.12 It is shown in Fig.11 A diagram of a deposition mask frame assembly in which no single unit mask is adhered to the deposition mask frame assembly; Fig.13 This is a diagram for explaining a method of welding a single unit mask 120 to a structural mask bar 110 .

[0083] like Fig.12 As shown, according to an embodiment of the present invention, a method for manufacturing a deposition mask frame assembly is as follows: Figure 3 and Figure 4 After the process, the structure of the unbonded monomer unit mask can be used with the mask strip 110 according to the Figures 5 to 10 The structural mask strip 110 may have an opening.

[0084] Then, if Fig.13 As shown, it may include a plurality of unit masks 120 arranged on the structural mask strip 110 (especially, the opening), and a step of fixing the unit masks on the structural mask strip by laser welding. Therefore, the assembly process of the unit masks is a subsequent process, so it can have the advantage of minimizing the position change of the deposition pattern hole P in the deposition mask frame assembly manufacturing process. Through such a process, Fig.11 A deposition mask frame assembly.

[0085] According to one embodiment, laser can be irradiated on the bottom of the structural mask strip 110 for welding. Therefore, burrs are formed on the bottom of the structural mask strip, and when the TFT glass and the hybrid mask strip are closely attached during the deposition process, there is no gap to achieve close attachment, thereby reducing the shadow effect.

Claims

1. A method for manufacturing a deposition mask frame assembly, using a deposition mask strip to manufacture a deposition mask frame assembly, wherein the deposition mask strip is composed of a structural mask strip and a plurality of monomer unit masks, wherein the structural mask strip has a frame and ribs, and the monomer unit mask is formed with a plurality of deposition pattern holes, characterized in that: The steps include: Disposing a frame having a quadrilateral shape in which a hollow portion is formed; A supporting mask strip is arranged on the frame, and the supporting mask strip is welded to the frame in a state where the supporting mask strip is stretched in a Y-axis direction along a length direction; A slit mask strip is arranged on the frame, and the slit mask strip is welded to the frame in a state where the slit mask strip is stretched along the length direction in the X-axis direction; and A deposition mask strip is arranged on the frame, and the deposition mask strip is stretched along the length direction in the X-axis direction, and the frame is welded to the frame in a state of adhesion and stretching in the Y-axis direction. wherein the supporting mask strip has an opening; The laser is irradiated on the lower opening of the supporting mask strip and the area outside the lower opening to weld the overlapping area of ​​the supporting mask strip, the slit mask strip and the frame.

2. The method for manufacturing a deposition mask frame assembly according to claim 1, characterized in that: It also includes the following steps: The overlapping area of ​​the supporting mask strip and the slit mask strip is welded to fix the slit mask strip on the supporting mask strip.

3. The method for manufacturing a deposition mask frame assembly according to claim 2, characterized in that: It also includes the following steps: The deposition mask strip is configured so that the ribs are located on the supporting mask strip, and the area (WZ 1) where the ribs overlap the supporting mask strip is welded to fix the deposition mask strip on the supporting mask strip.

4. The method for manufacturing a deposition mask frame assembly according to claim 3, characterized in that: It also includes the following steps: The deposition mask strip is configured so that a portion of the frame is located on the slit mask strip, so as to weld the overlapping area of ​​the support mask strip, the slit mask strip and the frame.

5. The method for manufacturing a deposition mask frame assembly according to claim 3, characterized in that: The laser is irradiated on the bottom of the supporting mask strip to weld the area (WZ1) where the rib overlaps with the supporting mask strip.

6. A deposition mask frame assembly manufactured by the manufacturing method according to claim 1.

7. An OLED display device manufactured using the deposition mask frame assembly of claim 6.

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