KR102283202B1 - Transfer system of mask and producing method of mask integrated frame - Google Patents

Abstract

The present invention relates to a mask transport system and a method for manufacturing a frame-integrated mask. The mask transport system according to the present invention is a transport system of a mask for forming an OLED pixel that loads and transports the mask 100 in the process of integrally forming the mask 100 and the frame 200 supporting the mask 100 . As such, it is characterized in that it includes a mask loading unit 90 capable of adsorbing and loading one surface of the mask 100 and a transfer unit 92 that moves and flips the mask loading unit 90 .

Description

Mask transport system and frame-integrated mask manufacturing method {TRANSFER SYSTEM OF MASK AND PRODUCING METHOD OF MASK INTEGRATED FRAME}

The present invention relates to a mask transport system and a method for manufacturing a frame-integrated mask. More specifically, the mask transport system and the frame-integrated mask that can make the mask integral with the frame, improve the adhesion between the mask and the frame, and clarify the alignment between the masks It relates to a manufacturing method.

Recently, in the manufacture of thin plates, research on an electroforming method has been conducted. The electroplating method immerses the anode body and the cathode body in an electrolyte, and applies power to electrodeposit a thin metal plate on the surface of the cathode body, so that an ultra-thin plate can be manufactured and mass production can be expected.

On the other hand, as a technology for forming a pixel in the OLED manufacturing process, the FMM (Fine Metal Mask) method is mainly used to deposit an organic material at a desired location by attaching a thin metal mask to the substrate.

In the existing OLED manufacturing process, the mask is manufactured in the form of a stick or plate, and then the mask is welded and fixed to the OLED pixel deposition frame. A plurality of cells corresponding to one display may be provided in one mask. In addition, for large-area OLED manufacturing, several masks can be fixed to the OLED pixel deposition frame, and in the process of fixing to the frame, each mask is stretched so that it is flat. Adjusting the tension so that the entire part of the mask is flat is a very difficult task. In particular, in order to align a mask pattern with a size of only several to tens of μm while flattening each cell, a high-level operation is required to check the alignment state in real time while finely adjusting the tensile force applied to each side of the mask. do.

Nevertheless, in the process of fixing a plurality of masks to one frame, there is a problem in that the masks are not well aligned with each other and between the mask cells. 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 large, the mask is sagging or twisted by load, and wrinkles and burrs occurring in the welding part during the welding process of the mask cell There were problems such as misalignment of the alignment.

In the case of ultra-high-definition OLED, the current QHD image quality is 500-600 PPI (pixel per inch) with a pixel size of about 30-50 μm, and 4K UHD and 8K UHD high-definition are higher than this: ~860 PPI, ~1600 PPI, etc. has a resolution of As such, it is necessary to reduce the alignment error between cells by several μm in consideration of the pixel size of the ultra-high-definition OLED, and an error outside of this may lead to product failure, and thus the yield may be very low. Therefore, there is a need to develop a technology capable of preventing deformation, such as sagging or twisting of the mask, and clarifying alignment, a technology of fixing the mask to a frame, and the like.

Accordingly, the present invention has been devised to solve the problems of the prior art as described above, and when attaching the mask to the frame, it is possible to prevent deformation of the mask and improve the adhesion between the mask and the frame. Its purpose is to provide

In addition, an object of the present invention is to provide a mask transport system that can spread the mask flat and transport it stably.

Another object of the present invention is to provide a method for manufacturing a frame-integrated mask in which the mask and the frame can form an integrated structure.

Another object of the present invention is to provide a method of manufacturing a frame-integrated mask capable of preventing deformation such as sagging or warping of the mask and clear alignment.

Another object of the present invention is to provide a method for manufacturing a frame-integrated mask that significantly reduces manufacturing time and significantly increases yield.

The above object of the present invention is a mask loading system capable of loading and adsorbing one surface of the mask as a transport system for a mask for forming an OLED pixel that loads and transports the mask in the process of integrally forming the mask and the frame supporting the mask. wealth; and a transport that moves and flips the mask loading part.

The mask loading unit has a flat plate shape, and a plurality of vacuum holes may be formed on one surface corresponding to the mask.

A depression may be formed at an edge of the mask loading unit.

The mask loading part is formed to have a larger area than the mask, and when the mask is loaded in the mask loading part, at least an edge of the mask may protrude outside the recessed part.

The mask loading unit may include a heating unit.

A laser passage hole may be formed in a portion of the mask loading portion corresponding to the welding portion of the mask.

The transfer unit may be connected to the other surface opposite to one surface of the mask loading unit in contact with the mask.

The transfer unit may move the mask loading unit in the X, Y, Z, and θ axes, and flip the mask so that it faces downward.

In addition, the above object of the present invention is a method of manufacturing a frame-integrated mask in which at least one mask and a frame supporting the mask are integrally formed, comprising the steps of: (a) providing a frame having at least one mask cell region; (b) loading one surface of the mask by adsorbing it to the mask loading unit; (c) loading a mask loading unit on the frame to correspond the mask to the mask cell region of the frame; and (d) attaching the mask to the frame by irradiating a laser to the welded portion of the mask.

Step (a) comprises the steps of: (a1) providing an edge frame portion including a hollow region; (a2) connecting the flat mask cell sheet portion to the edge frame portion; and (a3) forming a plurality of mask cell regions in the mask cell sheet portion to manufacture a frame.

Step (a) comprises the steps of: (a1) providing an edge frame portion including a hollow region; and (a2) manufacturing a frame by connecting a mask cell sheet portion having a plurality of mask cell regions to an edge frame portion.

The mask loading part has a flat plate shape, and a plurality of vacuum holes are formed on one surface corresponding to the mask, and in step (b), suction pressure is applied to one surface of the mask in the plurality of vacuum holes to remove the mask from the mask loading part can be adsorbed onto the

(b) step, (b1) the vacuum transfer unit adsorbing at least two sides of the mask; and (b2) adsorbing one surface of the mask to the mask loading unit by moving the vacuum transfer unit and loading the mask.

In step (b1) or (b2), the vacuum transfer unit may flatten the mask by pulling the adsorbed mask outward.

A depression is formed in the corner of the mask loading part, and in step (b), when the mask is loaded in the mask loading part, at least a corner of the mask may protrude outside the depression.

Step (c) includes: (c1) flipping the mask loading unit so that the mask faces downward; (c2) aligning the mask on the cell region of the frame by controlling the position of the mask loading unit by the transfer unit; and (c3) loading a mask loading unit on the frame to correspond the mask to the mask cell region of the frame.

A laser passage hole may be formed in a portion of the mask loading portion corresponding to the welding portion of the mask.

The laser irradiated from the upper part of the mask loading part may be irradiated to the welding part of the mask through the laser passing hole.

A welding bead is formed in a portion of the welding portion irradiated with a laser, and the welding bead may mediate so that the mask and the frame are integrally connected.

Before or after the mask corresponds to the mask cell region, the temperature of the process region including the frame is raised to a first temperature, and after attaching the mask to the frame, the temperature of the process region including the frame is increased to a second temperature can be lowered to

The first temperature may be equal to or higher than the OLED pixel deposition process temperature, and the second temperature may be at least lower than the first temperature.

The first temperature is any one of 25°C to 60°C, the second temperature is any one of 20°C to 30°C lower than the first temperature, and the OLED pixel deposition process temperature is any one of 25°C to 45°C It can be one temperature.

When the mask corresponds to the mask cell region, tension may not be applied to the mask.

When the temperature of the process region is lowered to the second temperature, the mask attached to the frame may be contracted and tension may be applied.

The mask loading unit may include a heating unit, and between steps (b) and (c), the mask may be maintained at a temperature 3° C. to 10° C. higher than the first temperature.

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

The mask cell sheet unit includes: an edge sheet unit; and at least one first grid sheet part extending in the first direction and having both ends connected to the edge sheet part.

The mask cell sheet unit may further include at least one second grid sheet unit extending in a second direction perpendicular to the first direction, intersecting the first grid sheet unit, and having both ends connected to the edge sheet unit.

The mask and the frame may be made of any one of invar, super invar, nickel, and nickel-cobalt.

According to the present invention configured as described above, when the mask is attached to the frame, it is possible to prevent deformation of the mask and improve the adhesion between the mask and the frame.

In addition, according to the present invention, there is an effect that the mask can be spread flat and transferred to a stable table.

In addition, according to the present invention, there is an effect that the mask and the frame can form an integrated structure.

In addition, according to the present invention, there is an effect of preventing deformation such as sagging or twisting of the mask and clarifying alignment.

In addition, according to the present invention, there is an effect that can significantly reduce the manufacturing time and significantly increase the yield.

1 is a schematic diagram showing a conventional mask for OLED pixel deposition.
2 is a schematic diagram illustrating a process of attaching a conventional mask to a frame.
3 is a schematic diagram illustrating that an alignment error occurs between cells in a process of tensioning a conventional mask.
4 is a front view and a side cross-sectional view showing a frame-integrated mask according to an embodiment of the present invention.
5 is a front view and a side cross-sectional view showing a frame according to an embodiment of the present invention.
6 is a schematic diagram illustrating a manufacturing process of a frame according to an embodiment of the present invention.
7 is a schematic diagram showing a manufacturing process of a frame according to another embodiment of the present invention.
8 is a schematic diagram illustrating components of a mask transport system according to an embodiment of the present invention.
9 is a schematic view showing a state in which the vacuum transfer unit is adsorbed to the mask according to an embodiment of the present invention.
10 is a schematic diagram illustrating an operation process of a mask transfer system according to an embodiment of the present invention.
11 is a schematic diagram illustrating a state in which a tray is loaded onto a frame and a mask corresponds to a cell region of the frame according to an embodiment of the present invention.
12 is a schematic diagram illustrating a process of sequentially attaching a mask to a cell region according to an embodiment of the present invention.
13 is a schematic diagram illustrating a process of lowering the temperature of a process region after attaching a mask to a cell region of a frame according to an embodiment of the present invention.
14 is a schematic diagram illustrating an OLED pixel deposition apparatus using a frame-integrated mask according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [0023] Reference is made to the accompanying drawings, which show by way of illustration specific embodiments in which the present invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the present invention. It should be understood that the various embodiments of the present invention are different but need not be mutually exclusive. For example, certain shapes, structures, and characteristics described herein with respect to one embodiment may be embodied in other embodiments without departing from the spirit and scope of the invention. In addition, it should be understood that the location or arrangement of individual components within each disclosed embodiment may be changed without departing from the spirit and scope of the present invention. Accordingly, the detailed description set forth below is not intended to be taken in a limiting sense, and the scope of the invention, if properly described, is limited only by the appended claims, along with all scope equivalents to those claimed. In the drawings, like reference numerals refer to the same or similar functions in various aspects, and the length, area, thickness, and the like may be exaggerated for convenience.

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

1 is a schematic diagram showing a conventional mask 10 for OLED pixel deposition.

Referring to FIG. 1 , the conventional mask 10 may be manufactured in a stick-type or plate-type shape. The mask 10 shown in FIG. 1A is a stick-type mask, and can be used by welding and fixing both sides of the stick to the OLED pixel deposition frame. The mask 100 illustrated in FIG. 1B is a plate-type mask and may be used in a process of forming a large area pixel.

A plurality of display cells C are provided in the body of the mask 10 (or the mask film 11 ). One cell C corresponds to one display such as a smart phone. A pixel pattern P is formed in the cell C to correspond to each pixel of the display. When the cell C is enlarged, a plurality of pixel patterns P corresponding to R, G, and B appear. For example, a pixel pattern P is formed in the cell C to have a resolution of 70×140. That is, numerous pixel patterns P form a group to constitute one cell C, and a plurality of cells C may be formed on the mask 10 .

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

Referring to FIG. 2A , first, the stick mask 10 should be flattened. The stick mask 10 is unfolded as it is pulled by applying tensile forces F1 to F2 in the long axis direction of the stick mask 10 . In this state, the stick mask 10 is loaded on the frame 20 in the form of a square frame. The cells C1 to C6 of the stick mask 10 are located in the blank area inside the frame 20 of the frame 20 . The frame 20 may have a size such that the cells C1 to C6 of one stick mask 10 are located in an empty area inside the frame, and the cells C1 to C6 of the plurality of stick masks 10 are placed in the frame. It may be large enough to be located in the inner blank area.

Referring to Figure 2 (b), after aligning while finely adjusting the tensile force (F1 ~ F2) applied to each side of the stick mask 10, a part of the side of the stick mask 10 is welded (W) Accordingly, the stick mask 10 and the frame 20 are interconnected. FIG. 2(c) shows a cross-section of the stick mask 10 and the frame connected to each other.

Referring to FIG. 3 , in spite of finely adjusting the tensile forces F1 to F2 applied to each side of the stick mask 10 , there is a problem in that the mask cells 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 patterns P are skewed. Since the stick mask 10 has a large area including a plurality of (eg, six) cells C1 to C6 and has a very thin thickness of several tens of μm, it is easily sagged or twisted by a load. In addition, it is very difficult to check the alignment state between the cells C1 to C6 in real time through a microscope while adjusting the tensile force F1 to F2 to flatten all the cells C1 to C6.

Accordingly, a minute error in the tensile force F1 to F2 may cause an error in the extent to which each cell C1 to C3 of the stick mask 10 is stretched or unfolded, and accordingly, the distance D1 between the mask patterns P ~D1", D2~D2") causes a problem that becomes different. Of course, it is difficult to align perfectly so that the error is 0, but in order to prevent the mask pattern P having a size of several to several tens of μm from adversely affecting the pixel process of the ultra-high-definition OLED, the alignment error should not exceed 3 μm. It is preferable not to This alignment error between adjacent cells is referred to as pixel position accuracy (PPA).

In addition, approximately 6 to 20 of a plurality of stick masks 10 are connected to one frame 20 , respectively, between the plurality of stick masks 10 and a plurality of cells C of the stick mask 10 . It is also very difficult to clarify the alignment state between ~C6), and the processing time according to alignment is inevitably increased, which is a significant reason for reducing productivity.

Meanwhile, after the stick mask 10 is connected and fixed to the frame 20 , the tensile forces F1 to F2 applied to the stick mask 10 may reversely act on the frame 20 . That is, after the stick mask 10 , which has been stretched taut by the tensile forces F1 to F2 , is connected to the frame 20 , a tension may be applied to the frame 20 . Usually, this tension is not large, so it may not have a significant effect on the frame 20 , but when the size of the frame 20 is reduced in size and rigidity is lowered, this tension may slightly deform the frame 20 . In this way, a problem in which the alignment state is misaligned among the plurality of cells C to C6 may occur.

Accordingly, the present invention proposes a frame 200 and a frame-integrated mask that allows the mask 100 to form an integrated structure with the frame 200 . The mask 100 integrally formed with the frame 200 is prevented from being deformed such as sagging or twisting, and can be clearly aligned with the frame 200 . Since no tensile force is applied to the mask 100 when the mask 100 is connected to the frame 200, a tension sufficient to deform the frame 200 after the mask 100 is connected to the frame 200 may not be applied. . And, it has the advantage of significantly reducing the manufacturing time for integrally connecting the mask 100 to the frame 200 and significantly increasing the yield.

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 frame-integrated mask according to an embodiment of the present invention. It is a front view [FIG. 5(a)] and a side cross-sectional view [FIG. 5(b)] which show a frame.

4 and 5 , the frame-integrated mask may include a plurality of masks 100 and one frame 200 . In other words, a plurality of masks 100 are attached to the frame 200 one by one. Hereinafter, for convenience of explanation, the mask 100 having a rectangular shape will be described as an example, but the masks 100 may be in the form of a stick mask having protrusions clamped on both sides before being attached to the frame 200 , and the frame 200 . ) after being attached to the protrusion can be removed.

A plurality of mask patterns P may be formed on each mask 100 , and one cell C may be formed on one mask 100 . One mask cell C may correspond to one display such as a smart phone. To form a thin film, the mask 100 may be formed by electroforming. Mask 100 may be a coefficient of thermal expansion of about 1.0 X 10 ^-6 / ℃ of invar (invar), about 1.0 X 10 ^-7 / ℃ Super Invar (super invar) material. Since the mask 100 made of this material has a very low coefficient of thermal expansion, there is little fear that the pattern shape of the mask is deformed by thermal energy, so it can be used as a fine metal mask (FMM) or a shadow mask in high-resolution OLED manufacturing. In addition, considering that technologies for performing a pixel deposition process in a range where a temperature change value is not large recently, the mask 100 may be formed of nickel (Ni) or nickel-cobalt (Ni-Co) having a slightly larger coefficient of thermal expansion than this. ) may be a material such as The thickness of the mask may be about 2 μm to 50 μm.

The frame 200 is formed so that a plurality of masks 100 can be attached thereto. The frame 200 may include several corners formed in a first direction (eg, a horizontal direction) and a second direction (eg, a vertical direction) including an outermost edge. These various corners may define a region on the frame 200 to which the mask 100 is to be attached.

The frame 200 may include an edge frame portion 210 having a substantially rectangular shape or a rectangular frame shape. The inside of the edge frame part 210 may have a hollow shape. That is, the edge frame portion 210 may include the hollow region (R). The frame 200 may be made of a metal material such as Invar, Super Invar, aluminum, or titanium, and is made of Invar, Super Invar, Nickel, Nickel-Cobalt, etc., having the same coefficient of thermal expansion as the mask in consideration of thermal deformation. Preferably, these materials may be applied to both the edge frame part 210 and the mask cell sheet part 220 that are components of the frame 200 .

In addition, the frame 200 may include a plurality of mask cell regions CR, and may include a mask cell sheet unit 220 connected to the edge frame unit 210 . Like the mask 100 , the mask cell sheet unit 220 may be formed by electroplating, or may be formed using other film forming processes. In addition, the mask cell sheet unit 220 may be connected to the edge frame unit 210 after forming a plurality of mask cell regions CR on a flat sheet through laser scribing, etching, or the like. Alternatively, the mask cell sheet unit 220 may form a plurality of mask cell regions CR through laser scribing, etching, or the like after connecting a flat sheet to the edge frame unit 210 . In the present specification, it is mainly assumed that a plurality of mask cell regions CR are first formed on the mask cell sheet part 220 and then connected to the edge frame part 210 .

The mask cell sheet part 220 may include at least one of the edge sheet part 221 and the first and second grid sheet parts 223 and 225 . The edge sheet portion 221 and the first and second grid sheet portions 223 and 225 refer to partitioned portions of the same sheet, and they are integrally formed with each other.

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

Also, the first grid sheet part 223 may be formed to extend in a first direction (horizontal direction). The first grid sheet part 223 may be formed in a straight shape so that both ends thereof may be connected to the edge sheet part 221 . When the mask cell sheet part 220 includes a plurality of first grid sheet parts 223 , it is preferable that each of the first grid sheet parts 223 form equal intervals.

In addition, the second grid sheet part 225 may be formed to extend in the second direction (vertical direction). The second grid sheet part 225 may be formed in a straight shape so that both ends thereof may be connected to the edge sheet part 221 . The first grid sheet part 223 and the second grid sheet part 225 may vertically cross each other. When the mask cell sheet part 220 includes a plurality of second grid sheet parts 225 , it is preferable that the respective second grid sheet parts 225 form equal intervals.

Meanwhile, the distance between the first grid sheet parts 223 and the distance between the second grid sheet parts 225 may be the same or different depending on the size of the mask cell C. As shown in FIG.

Although the first grid sheet part 223 and the second grid sheet part 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 a rectangle, a rectangular shape such as a parallelogram, a triangular shape, etc. , sides and corners may be partially rounded. The cross-sectional shape can be adjusted in the process of laser scribing, etching, etc.

The thickness of the edge frame part 210 may be thicker than the thickness of the mask cell sheet part 220 . The edge frame portion 210 may be formed to a thickness of several mm to several cm because it is responsible for the overall rigidity of the frame (200).

In the case of the mask cell sheet part 220, the process of manufacturing a substantially thick sheet is difficult, and if it is too thick, the organic material source 600 (see FIG. 14 ) passes through the mask 100 in the OLED pixel deposition process. It may cause clogging problems. Conversely, if the thickness is too thin, it may be difficult to secure enough rigidity to support the mask 100 . Accordingly, the mask cell sheet portion 220 is thinner than the thickness of the edge frame portion 210 , but preferably thicker than the mask 100 . The thickness of the mask cell sheet part 220 may be about 0.1 mm to about 1 mm. In addition, the width of the first and second grid sheet parts 223 and 225 may be about 1 to 5 mm.

In the flat sheet, a plurality of mask cell regions CR: CR11 to CR56 may be provided except for regions occupied by the edge sheet part 221 and the first and second grid sheet parts 223 and 225 . From another point of view, the mask cell region CR refers to an area occupied by the edge sheet part 221 and the first and second grid sheet parts 223 and 225 in the hollow region R of the edge frame part 210 . , but may mean an empty area.

As the cell C of the mask 100 corresponds to the mask cell region CR, it can be used as a path through which the pixels of the OLED are deposited substantially through the mask pattern P. As described above, one mask cell C corresponds to one display such as a smart phone. Mask patterns P constituting one cell C may be formed on one mask 100 . Alternatively, one mask 100 may include a plurality of cells C, and each cell C may correspond to each cell region CR of the frame 200, but the mask 100 may be clearly aligned. For this, it is necessary to avoid the large-area mask 100 , and the small-area mask 100 including one cell C is preferable. Alternatively, one mask 100 having a plurality of cells C may correspond to one cell region CR of the frame 200 . In this case, it may be considered to correspond to the mask 100 having a small number of cells C of about 2-3 for clear alignment.

The frame 200 includes a plurality of mask cell regions CR, and each mask 100 may be attached such that one mask cell C corresponds to the mask cell region CR. Each mask 100 may include a mask cell C on which a plurality of mask patterns P are formed and a dummy (corresponding to a portion of the mask film 110 excluding the cell C) around the mask cell C. there is. The dummy may include only the mask layer 110 or the mask layer 110 on which a predetermined dummy pattern similar to the mask pattern P is formed. The mask cell C corresponds to the mask cell region CR of the frame 200 , and a part or all of the dummy may be attached to the frame 200 (mask cell sheet unit 220 ). Accordingly, the mask 100 and the frame 200 can form an integrated structure.

Meanwhile, according to another embodiment, the frame is not manufactured by attaching the mask cell sheet unit 220 to the frame frame unit 210 , but the frame frame unit 210 is formed in the hollow region R of the frame frame unit 210 . ) and a grid frame (corresponding to the grid sheet portions 223 and 225) integrally formed thereon may be used. This type of frame also includes at least one mask cell region CR, and by matching the mask 100 to the mask cell region CR, a frame-integrated mask can be manufactured.

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

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

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

Next, referring to FIG. 6B , the mask cell sheet part 220 is manufactured. The mask cell sheet part 220 can be manufactured by manufacturing a flat sheet using electroplating or other film forming process, and then removing the mask cell region CR part through laser scribing, etching, etc. there is. In the present specification, a case in which 6 X 5 mask cell regions CR: CR11 to CR56 are formed will be described as an example. Five first grid sheet parts 223 and four second grid sheet parts 225 may exist.

Next, the mask cell sheet part 220 may correspond to the edge frame part 210 . In the process of matching, all sides of the mask cell sheet part 220 are stretched (F1 to F4), and the edge sheet part 221 is attached to the edge frame part 210 in a state where the mask cell sheet part 220 is flattened. can respond. One side may also hold the mask cell sheet 220 at several points (eg, 1 to 3 points in FIG. 6(b) ) and tension it. Meanwhile, the mask cell sheet unit 220 may be stretched (F1, F2) along some lateral directions instead of all sides.

Next, when the mask cell sheet part 220 corresponds to the edge frame part 210 , the edge sheet part 221 of the mask cell sheet part 220 may be attached by welding (W). It is preferable to weld (W) all sides so that the mask cell sheet part 220 can be firmly attached to the edge frame part 220 . Welding (W) should be performed as close to the edge of the edge frame part 210 as possible to reduce the floating space between the edge frame part 210 and the mask cell sheet part 220 as much as possible and increase adhesion. The weld (W) portion may be generated in the form of a line or a spot, and has the same material as the mask cell sheet 220 and integrates the edge frame 210 and the mask cell sheet 220 together. It can be a medium that connects

7 is a schematic diagram showing a manufacturing process of a frame according to another embodiment of the present invention. In the embodiment of FIG. 6 , the mask cell sheet part 220 having the mask cell region CR is first manufactured and attached to the edge frame part 210 , but in the embodiment of FIG. 7 , a flat sheet is used as the edge frame part ( After attaching to 210 , a mask cell region CR portion is formed.

First, as shown in (a) of Figure 6, the frame portion 210 including the hollow region (R) is provided.

Next, referring to FIG. 7A , a flat sheet (planar mask cell sheet portion 220 ′) may correspond to the edge frame portion 210 . The mask cell sheet part 220 ′ is in a planar state in which the mask cell region CR is not yet formed. In the process of matching, all sides of the mask cell sheet part 220' may be stretched (F1 to F4) to correspond to the edge frame part 210 in a state in which the mask cell sheet part 220' is flattened. On one side, the mask cell sheet unit 220 ′ may be held and tensioned at several points (eg, 1 to 3 points in FIG. 7A ). Meanwhile, the mask cell sheet unit 220 ′ may be stretched (F1, F2) along some lateral directions instead of all sides.

Next, when the mask cell sheet portion 220 ′ corresponds to the edge frame portion 210 , the edge portion of the mask cell sheet portion 220 ′ may be attached by welding (W). It is preferable to weld (W) all sides so that the mask cell sheet part 220 ′ can be firmly attached to the edge frame part 220 . Welding (W) should be performed as close as possible to the edge of the edge frame part 210, so that the floating space between the edge frame part 210 and the mask cell sheet part 220' can be reduced as much as possible and adhesion can be increased. The weld (W) portion may be formed in the form of a line or a spot, and has the same material as the mask cell sheet portion 220 ′, and includes the edge frame portion 210 and the mask cell sheet portion 220 ′. It can be a medium that connects them together.

Next, referring to FIG. 7B , a mask cell region CR is formed on a flat sheet (planar mask cell sheet portion 220 ′). The mask cell region CR may be formed by removing the sheet of the mask cell region CR through laser scribing, etching, or the like. In the present specification, a case in which 6 X 5 mask cell regions CR: CR11 to CR56 are formed will be described as an example. When the mask cell region CR is formed, the edge frame portion 210 and the welded portion W become the edge sheet portion 221 , and five first grid sheet portions 223 and four second grids are formed. The mask cell sheet unit 220 including the sheet unit 225 may be configured.

8 is a schematic diagram illustrating components of a transport system for a mask 100 according to an embodiment of the present invention. Fig. 8 (a) is a plan view and a side cross-sectional view showing the mask 100, Fig. 8 (b) is a plan cross-sectional view and a side cross-sectional view showing the tray 50, Fig. 8 (c) is a mask loading part 90 A plan cross-sectional view and a side cross-sectional view showing The tray 50 and the mask loading unit 90, which are the transport system of the mask 100, correspond to and attach the mask 100 to the frame 200. Before attaching the mask 100 to the frame 200, can mean

Referring to FIG. 8A , a mask 100 having a plurality of mask patterns P formed thereon may be provided. The mask 100 may include a mask cell C on which a plurality of mask patterns P are formed and a dummy DM around the mask cell C. The dummy DM corresponds to a portion of the mask layer 110 excluding the cell C, and includes only the mask layer 110 or the mask layer 110 on which a predetermined dummy pattern similar to the mask pattern P is formed. may include. A part or all of the dummy DM may be attached to the frame 200 (the mask cell sheet unit 220 ) corresponding to the edge of the mask 100 . The mask 100 made of Invar or Super Invar material can be manufactured by electroplating.

The mother plate used as a cathode in electroplating uses a conductive material. As a conductive material, in the case of a metal, metal oxides may be generated on the surface, impurities may be introduced during the metal manufacturing process, and in the case of a polycrystalline silicon substrate, inclusions or grain boundaries may exist, and a conductive polymer In the case of a base material, it is highly likely to contain impurities, and strength. Acid resistance, etc. may be weak. Elements that prevent the uniform formation of an electric field on the surface of the mother plate (or cathode body), such as metal oxides, impurities, inclusions, and grain boundaries, are referred to as “defects”. Due to the defect, a uniform electric field may not be applied to the cathode body made of the above material, so that a portion of the plating film (mask 100 ) may be non-uniformly formed.

In realizing ultra-high-definition pixels of UHD level or higher, the non-uniformity of the plating film and the plating film pattern (mask pattern P) may adversely affect the formation of the pixel. For example, in the case of the current QHD image quality, the pixel size reaches about 30-50㎛ with 500-600 PPI (pixel per inch), and in the case of 4K UHD and 8K UHD high definition, ~860 PPI and ~1600 PPI resolution, etc. A micro display applied directly to a VR device or a micro display used by inserting a VR device aims for an ultra-high resolution of about 2,000 PPI or higher, and the size of the pixel reaches about 5 to 10 μm. The pattern width of the FMM and shadow mask applied thereto can be formed in a size of several to several tens of μm, preferably smaller than 30 μm, so that even defects with a size of several μm occupy a large proportion in the pattern size of the mask. am. In addition, in order to remove defects in the anode body made of the above material, an additional process for removing metal oxides, impurities, etc. may be performed, and in this process, other defects such as etching of the cathode body material may be induced. there is.

Accordingly, in the present invention, a single crystal material mother plate (or negative electrode body) may be used. In particular, it is preferable that the material is single-crystal silicon. In order to have conductivity, a ^{high-concentration doping of 10 19} /cm ³ or more may be performed on the mother plate made of single-crystal silicon. The doping may be performed on the entire mother plate or only on the surface portion of the mother plate.

On the other hand, as a single crystal material, metals such as Ti, Cu, Ag, semiconductors such as GaN, SiC, GaAs, GaP, AlN, InN, InP, Ge, and carbon-based materials such as graphite and graphene _{, CH 3 NH 3 PbCl 3,} CH 3 NH 3 PbBr 3, CH 3 NH 3 PbI 3, SrTiO 3 , etc. page containing the perovskite (perovskite) superconductor single crystalline ceramic, aircraft single crystal second heat-resistant alloy for components for such structures etc. may be used. Metals and carbon-based materials are basically conductive materials. In the case of a semiconductor material, high-concentration doping of 1019 or more may be performed to have conductivity. In the case of other materials, conductivity may be formed by doping or forming oxygen vacancies. The doping may be performed on the entire mother plate or only on the surface portion of the mother plate.

In the case of a single crystal material, since there is no defect, there is an advantage that a uniform plating film (mask 100 ) can be generated due to the formation of a uniform electric field on the entire surface during electroplating. The frame-integrated masks 100 and 200 manufactured through a uniform plating film can further improve the quality of OLED pixels. And, since there is no need to perform an additional process for removing and resolving defects, there is an advantage in that process costs are reduced and productivity is improved.

In addition, if it is a silicon material or a single crystal material capable of forming an insulating film on the surface by oxidation or nitridation, the advantage of being able to form an insulating part only by oxidizing and nitriding the surface of the mother plate if necessary. there is. The insulating portion may be formed using a photoresist. Electrodeposition of the plating film (mask 100) is prevented in the portion where the insulating portion is formed, and a pattern (mask pattern P) is formed on the plating film.

On the other hand, it should be noted that the material of the mother plate of the present invention is not necessarily limited to the above-described single crystal material as long as it is within the range of reducing defects in the cathode body.

The width of the mask pattern P may be formed to be smaller than 40 μm, and the thickness of the mask 100 may be formed to be about 2 to 50 μm. Since the frame 200 includes a plurality of mask cell regions CR: CR11 to CR56, the mask 100 having mask cells C: C11 to C56 corresponding to each of the mask cell regions CR: CR11 to CR56. ) may also be provided in plurality.

Referring to FIG. 8B , a mask loading unit 90 may be provided. The mask loading unit 90 may provide a space for loading the mask 100 before moving to the frame 200 by flattening the manufactured mask 100 . The mask loading unit 90 preferably has a flat plate shape so that the mask 100 can be loaded flat. The size of the mask loading unit 90 may be a flat plate shape larger than that of the mask 100 so that the mask 100 can be loaded flat as a whole.

When the mask 100 is loaded, or after it is loaded, the mask loading unit 90 may adsorb one surface of the mask 100 so that the mask 100 does not have wrinkles and maintains a flat state. A plurality of vacuum holes (VH) may be formed on one surface of the mask loading part 90 corresponding to the mask 100 so that the mask loading part 90 can adsorb one surface of the mask 100 . there is. The mask loading unit 90 may be connected to an external pumping means (not shown) to pump air in the mask loading unit 90 to transmit suction pressure to the vacuum hole VH. The mask 100 may be completely absorbed by the mask loading unit 90 by the suction pressure of the plurality of vacuum holes VH.

The mask loading part 90 may have a recessed part 91 formed at an edge thereof. Considering the square-shaped mask loading part 90 , recessed parts 91 may be formed in each of the four corners. When the mask 100 is loaded on the mask loading part 90 , a portion of the mask 100 may protrude and be exposed to the outside of the recessed part 91 . Accordingly, it is possible to flatten the mask 100 using the protruding or exposed portion, or to grip the mask 100 through a grip means (not shown).

Meanwhile, the mask loading unit 90 may be opaque to the laser (L) light. Accordingly, in the mask loading part 90 of the present invention, the laser passing hole 92 is formed so that the laser L irradiated from the upper part of the mask loading part 90 can reach the welding part of the mask 100 . can be

Referring back to (b) of FIG. 8 , the laser passing hole 93 may be formed in the mask loading part 90 to correspond to the position and number of the welding part. Since a plurality of welding parts are disposed along a predetermined interval at the edge or the dummy DM portion of the mask 100 , a plurality of laser passing holes 93 may be formed along a predetermined interval to correspond thereto. For example, since a plurality of welding portions are disposed along a predetermined interval on both sides (left/right) dummy DM portions of the mask 100 , the laser passing holes 93 are also provided on both sides (left/right sides) of the mask loading unit 90 . ) may be formed in plurality along a predetermined interval.

The laser passing hole 93 does not necessarily correspond to the position and number of the welding part. For example, welding may be performed by irradiating the laser L to only a part of the laser passing hole 93 . In addition, some of the laser passage holes 93 that do not correspond to the welding portion may be used instead of a vacuum hole, which is a passage for applying vacuum suction pressure to the mask 100 in contact with one surface of the mask loading portion 90 . . In addition, some of the laser passing holes 93 that do not correspond to the welding part may be used instead of the alignment mark when aligning the mask 100 and the mask loading part 90 . If the material of the mask loading part 90 is transparent to the laser (L) light, the laser passing hole 93 may not be formed.

The mask loading unit 90 may be connected to the transfer unit 92 . The transfer unit 93 may be connected to the other surface opposite to one surface of the mask loading unit 90 in contact with the mask 100 . As shown in (b) of FIG. 8 , in order to stably support the mask loading part 90 , the transfer part 92 is preferably connected to the lower surface of the mask loading part 90 .

Moving means (not shown) such as rails and belts for moving along the X, Y, Z, and θ axes may be connected to the transfer unit 92 . In addition, a rotation shaft for flipping the mask loading unit 90 may be further connected to the transfer unit 92 . Alternatively, the housing of the mask loading unit 90 and the conveying unit 92 communicate with each other, and the conveying unit 92 is connected to an external pumping means (not shown) to apply suction pressure into the mask loading unit 90 to provide a vacuum hole (vh). It is also possible to transmit suction pressure to the

Hereinafter, a series of processes in which the mask 100 is processed in the transport system of the mask will be described.

9 is a schematic diagram illustrating a state in which the vacuum transfer unit 60 adsorbs the mask 100 according to an embodiment of the present invention.

Referring to FIG. 9 , the vacuum transfer unit 60 may adsorb the side of the mask 100 . The vacuum transfer unit 60 may flatten the mask 100 by pulling it outward after adsorbing the mask 100 .

The manufactured mask 100 may be loaded and attached to the frame 200 in a flat state. At this time, in the process of moving the mask 100 , the mask 100 is a thin film having a thickness of about 2 μm to 50 μm, and wrinkles may occur even when a slight force is applied, so care must be taken in handling it. In addition, since a plurality of fine mask patterns P are formed on the mask 100 , the mask 100 must be flattened without wrinkles so that the alignment of the mask patterns P is not misaligned. If both sides of the mask 100 are gripped with a gripper to move the mask 100 in an open state, damage to the mask 100 may occur, and it is not easy to load the mask 100 on the frame 200 because both sides are held. In addition, there is a problem in that it is very difficult to load the mask 100 on the frame 200 by holding the mask 100 with a gripper and moving it flat without an alignment error of the mask pattern P.

Accordingly, the vacuum transfer unit 60 may perform adsorption by the vacuum (V) on the side of the mask 100 . Here, the adsorption by the vacuum V does not mean that the environment around the mask 100 is made into a vacuum to be adsorbed. It may be understood that the mask 100 is adsorbed to the vacuum transfer unit 60 .

The vacuum transfer unit 60 may include a housing 61 , and a gas flow path 63 may be provided inside the housing 61 . One end of the housing 61 may be in contact with the side of the mask 100 , and the other end may be connected to an external pumping means (not shown). A pumping means (not shown) such as a pump may pump air from the gas flow path 63 inside the housing 61 to create a vacuum atmosphere inside the housing 61 . Accordingly, the mask 100 in contact with one end of the housing 61 may be adsorbed to the vacuum transfer unit 60 .

A porous part 65 may be disposed at one end of the housing 61 . The porous part 65 may be made of a porous material including very small pores. When the mask 100 is adsorbed to the vacuum transfer unit 60 through a hole or a slit, the size of the hole and the slit is large and the adsorption force is not uniform in the area where the hole and the slit are formed. Stress can be put on some. Accordingly, when a vacuum is applied between the pores of the porous part 65 , an adsorption force can be uniformly generated on the surface of the porous part 65 , so that the mask 100 can be stably adsorbed and moved.

The vacuum transfer unit 60 may adsorb at least two sides of the mask 100 . For example, two sides of the left and right sides of the mask 100 may be adsorbed, or four sides of the mask 100 may be adsorbed. As an example, in FIG. 9( a ), an example in which the two vacuum transfer units 60 adsorb the left and right sides of the mask 100 and pull them in the left and right directions is illustrated. As another example, in (b) of FIG. 9 , an example in which four vacuum transfer units 60 ′ can pull the mask 100 in the left, right, upper and lower directions by adsorbing the four corners of the mask 100 is shown. there is. However, the present invention is not limited thereto, and the number of the vacuum transfer units 60 may be determined in consideration of the pulling direction and movement of the mask 100 . A moving means (not shown) such as rails and belts for moving the vacuum transfer unit 60 in the X, Y, Z, and θ axes in order to pull or adsorb and move the mask 100 is connected to the vacuum transfer unit 60. can Hereinafter, description will be made assuming the form of FIG. 8(b).

10 is a schematic diagram illustrating an operation process of a mask transfer system according to an embodiment of the present invention.

Referring to FIG. 10A , the vacuum transfer unit 60 may adsorb the mask 100 and move it to the mask loading unit 90 . The mask 100 may be loaded onto the mask loading unit 90 in a state in which the four corners are adsorbed by the vacuum transfer unit 60 and spread flat. Alternatively, the vacuum transfer unit 60 may flatten the mask 100 while the mask 100 is loaded on the mask loading unit 90 .

Subsequently, suction pressure is applied to the mask 100 through the vacuum hole VH on the mask loading unit 90 to adsorb the mask 100 onto the mask loading unit 90 . Alternatively, suction pressure may be applied to the mask 100 through the vacuum hole VH while the vacuum transfer unit 60 moves the mask 100 onto the mask loading unit 90 .

On the other hand, even when the vacuum transfer unit 60 is not used, for example, grip the edge of the mask 100 with a gripper (not shown) and move it to the mask loading unit 90 , while unfolding the mask 100 . The mask 100 may be adsorbed by applying suction pressure in the vacuum hole VH of the loading unit 90 . Since the recessed part 91 is formed at the edge of the mask loading part 90 , the gripper may not interfere with the mask loading part 90 even if the gripper grips both sides of the edge of the mask 100 .

The welding part of the mask 100 may be loaded on the mask loading part 90 in a state corresponding to the laser passing hole 93 of the mask loading part 90 . When the mask 100 is loaded on the mask loading part 90 , at least a corner portion of the mask 100 may protrude and be exposed to the outside of the recessed part 91 .

Next, referring to FIG. 10B , the mask 100 may be flipped. The transfer unit 92 may move the mask loading unit 90 on the frame 200 and flip the mask loading unit 90 . Thus, the mask 100 adsorbed on the mask loading unit 90 may also be flipped. Alternatively, the transfer unit 92 may move the mask loading unit 90 on the frame 200 in a state in which the mask loading unit 90 is flipped. Even if the mask 100 is flipped, the suction pressure applied to the mask 100 from the vacuum hole VH of the mask loading part 90 can be maintained so that the alignment state on the mask loading part 90 is not disturbed. .

Subsequently, the mask 100 may be adsorbed and supported by the mask loading unit 90 to be transferred to the region of the frame 200 .

Hereinafter, a series of processes for attaching the mask 100 to the frame 200 after aligning and attaching the mask 100 will be described.

11 is a schematic diagram illustrating a state in which the mask 100 corresponds to the cell region CR of the frame 200 by loading the tray 50 on the frame according to an embodiment of the present invention.

Next, referring to FIGS. 11A and 11B , the mask 100 may correspond to one mask cell region CR of the frame 200 . By loading the mask loading unit 90 adsorbing and supporting the mask 100 on the frame 200 (or the mask cell sheet unit 220 ), the mask 100 may correspond to the mask cell region CR. there is. Before the mask loading unit 90 is loaded onto the frame 200 , the positions of the mask loading unit 90 and the mask 100 are controlled using the transfer unit 92 on the cell region CR of the frame 200 . You can align the mask 100 to Since the mask loading unit 90 is flipped so that the mask 100 faces downward, when the mask loading unit 90 is loaded on the frame 200 (or the mask cell sheet unit 220 ), the mask ( The mask 100 may be compressed by the mask loading unit 90 while being disposed between the mask loading unit 90 and the frame 200 (or the mask cell sheet unit 220 ).

Meanwhile, the lower support 70 may be further disposed under the frame 200 . The lower support 70 may have a size sufficient to fit into the hollow region R of the frame edge portion 210 and may have a flat plate shape. In addition, a predetermined support groove (not shown) corresponding to the shape of the mask cell sheet part 220 may be formed on the upper surface of the lower support body 70 . In this case, the edge sheet part 221 and the first and second grid sheet parts 223 and 225 are fitted into the support grooves, so that the mask cell sheet part 220 can be more well fixed.

The lower support 70 may press the opposite surface of the mask cell region CR to which the mask 100 contacts. That is, the lower support 70 may support the mask cell sheet 220 in the upper direction to prevent the mask cell sheet 220 from sagging in the lower direction during the process of attaching the mask 100 . At the same time, since the lower support 70 and the mask loading part 90 press the edge and the frame 200 (or the mask cell sheet part 220) of the mask 100 in opposite directions, the mask ( 100) can be maintained without being disturbed.

As such, by attaching the mask 100 on the mask loading unit 90 and loading the mask loading unit 90 on the frame 200 , the mask 100 is applied to the mask cell region CR of the frame 200 . Since the process corresponding to ) is completed, no tensile force may be applied to the mask 100 in this process.

Then, the mask 100 may be attached to the frame 200 by irradiating the laser L to the mask 100 by laser welding. The laser L may pass through the laser passage hole 91 of the mask loading part 90 to be irradiated to the welding part of the mask 100 . The welding part of the mask 100 may refer to a target area in which the welding bead WB is to be formed by irradiating the laser L. The welding portion may correspond to at least a partial region of the rim or the dummy DM portion of the mask 100 . A welding bead WB is generated in the welding portion of the laser-welded mask, and the welding bead WB may have the same material as that of the mask 100/frame 200 and may be integrally connected.

Again, referring to FIG. 11 , since the mask cell sheet part 220 of the frame 200 has a thin thickness, when it is attached to the mask cell sheet part 220 while a tensile force is applied to the mask 100, the mask ( The tensile force remaining in the 100 , may act on the mask cell sheet 220 and the mask cell region CR, and may deform them. Therefore, it is necessary to attach the mask 100 to the mask cell sheet 220 without applying a tensile force to the mask 100 . Thus, it is possible to prevent the frame 200 (or the mask cell sheet part 220 ) from being deformed by the tensile force applied to the mask 100 acting as tension on the frame 200 .

However, one problem arises when a frame-integrated mask is manufactured by attaching it to the frame 200 (or the mask cell sheet 220) without applying a tensile force to the mask 100, and the frame-integrated mask is used in a pixel deposition process. can occur In the pixel deposition process performed at about 25 to 45° C., the mask 100 is thermally expanded by a predetermined length. Even with the mask 100 made of Invar material, the length may vary by about 1 to 3 ppm according to a temperature increase of about 10° C. to form an atmosphere for the pixel deposition process. For example, when the total length of the mask 100 is 500 mm, the length may be increased by about 5 to 15 μm. Then, the mask 100 is hit by its own weight or is deformed, such as stretched and twisted in a fixed state in the frame 200 , and an alignment error of the patterns P increases.

Accordingly, the present invention is characterized in that it corresponds to and attaches to the mask cell region CR of the frame 200 without applying a tensile force to the mask 100 at a higher temperature than room temperature. In the present specification, it is expressed that the mask 100 corresponds to the frame 200 after the temperature of the process region is increased (ET) to the first temperature.

The “process region” may mean a space in which components such as the mask 100 and the frame 200 are located, and an attachment process of the mask 100 is performed. The process region may be a space in a closed chamber or an open space, and may refer only to a space around the stage unit (not shown) in which the process of attaching the mask 100 to the frame 200 is performed. Also, when the frame-integrated mask is used in the OLED pixel deposition process, the “first temperature” may mean a temperature that is higher than or equal to the pixel deposition process temperature. Considering that the pixel deposition process temperature is about 25 to 45°C, the first temperature may be about 25 to 60°C. The temperature increase of the process region may be performed by installing a heating means in the chamber, or by installing a heating means around the process region.

Again, referring to FIG. 11 , after the temperature of the process region including the frame 200 is increased (ET) to the first temperature, the mask 100 may correspond to the mask cell region CR. Alternatively, after the mask 100 corresponds to the mask cell region CR, the temperature of the process region including the frame 200 may be increased ET to the first temperature. Alternatively, although it is shown in the drawing that only one mask 100 corresponds to one mask cell region CR, after matching the masks 100 for each mask cell region CR, the temperature of the process region is set to the first temperature. It can also be raised to ET1.

Since the conventional mask 10 of FIG. 1 includes six cells (C1 to C6), it has a long length, whereas the mask 100 of the present invention has a short length including one cell (C). The degree of distortion of pixel position accuracy (PPA) may be reduced. For example, assuming that the length of the mask 10 including the plurality of cells C1 to C6, ... is 1 m, and a PPA error of 10 μm occurs in the entire 1 m, the mask 100 of the present invention can make the above error range 1/n according to the relative length reduction [corresponding to the reduction in the number of cells (C)]. For example, if the length of the mask 100 of the present invention is 100 mm, since it has a length reduced from 1 m to 1/10 of the conventional mask 10, a PPA error of 1 μm occurs over the entire length of 100 mm. , there is an effect that the alignment error is significantly reduced.

On the other hand, if the mask 100 includes a plurality of cells C, and each cell C corresponds to each cell region CR of the frame 200, within a range in which an alignment error is minimized, The mask 100 may correspond to a plurality of mask cell regions CR of the frame 200 . Alternatively, the mask 100 having a plurality of cells C may correspond to one mask cell region CR. Even in this case, in consideration of the process time and productivity according to the alignment, it is preferable that the mask 100 includes as few cells C as possible.

In the case of the present invention, since it is only necessary to match one cell (C) of the mask 100 and check the alignment state, it is necessary to simultaneously correspond a plurality of cells (C: C1 to C6) and check the alignment state. Compared to the conventional method (see Fig. 2), the manufacturing time can be significantly reduced.

That is, the frame-integrated mask manufacturing method of the present invention corresponds to each of the cells C11 to C16 included in the six masks 100 to one cell region CR11 to CR16 and checks the alignment state, respectively. Through this process, the time can be significantly reduced compared to the conventional method of simultaneously matching the six cells C1 to C6 and checking the alignment status of the six cells C1 to C6 at the same time.

In addition, in the frame-integrated mask manufacturing method of the present invention, the product yield in the 30-step process of matching and aligning 30 masks 100 to 30 cell regions (CR: CR11 to CR56) is 6 cells (C1). ~C6) each containing 5 masks 10 (see Fig. 2 (a)) can be shown to be much higher than the conventional product yield in the process of 5 times to correspond and align with the frame 20. Since the conventional method of aligning six cells C1 to C6 in an area corresponding to six cells C at a time is a much cumbersome and difficult task, the product yield appears low.

Meanwhile, after the mask 100 corresponds to the frame 200 , the mask 100 may be temporarily fixed to the frame 200 with a predetermined adhesive interposed therebetween. Thereafter, an attaching step of the mask 100 may be performed.

Also, according to an embodiment, the mask 100 may be preheated to a temperature higher than the first temperature before it corresponds to the frame 200 . Referring back to FIG. 8B , the mask loading unit 90 may further include a heating unit 95 . In step (a) of FIG. 10 , when the mask 100 is loaded on the mask loading unit 90 , the heating unit 95 of the mask loading unit 90 applies the mask 100 to a temperature higher than the first temperature. , for example, the mask 100 may be preheated to a temperature of about 3° C. to 10° C. higher than the first temperature.

When the mask 100 is directly raised to the first temperature and corresponds to the frame 200, the flat mask 100 is stretched, and fine wrinkles and curves of nm or μm level may occur on the surface. If it is, it may be difficult to perform alignment immediately before attaching the mask 100 to the frame 200, and even if the alignment and the mask 100 are attached to the frame 200, alignment between the mask pattern P and the cell C This error may occur.

Accordingly, after the mask 100 is preheated by the mask loading unit 90 , if the operation of the heating unit 95 is stopped before the mask 100 comes into contact with the frame 200 , the mask 100 is loaded with the mask When the unit 90 is adsorbed and supported in contact with the frame 200, or when entering the process region of the first temperature, the mask 100 lowers the temperature to the first temperature by about 3°C to 10°C, The mask 100 may be contracted while contracting a predetermined tension.

For this reason, it is possible to maintain a flat unfolded state without wrinkling or bending of the mask 100 . Since the temperature is lowered only by a small temperature of about 3°C to 10°C, the mask 100 is not deformed enough to affect the alignment of the mask pattern P and the cell C, but only a contraction enough to spread flat. can

Next, the flat spread mask 100 may be perfectly aligned with the frame 200 . Subsequently, at least a portion of the edge of the mask 100 may be attached to the frame 200 . The attachment can preferably be carried out by laser welding. Laser welding should be performed as close to the edge of the frame 200 as possible to reduce the floating space between the mask 100 and the frame 200 as much as possible and increase adhesion. A welding bead WB is generated in the welding portion of the laser-welded mask, and the welding bead WB may have the same material as that of the mask 100/frame 200 and may be integrally connected.

In the present invention, since welding is performed on the mask cell sheet unit 220 without applying a tensile force to the mask 100 , the mask cell sheet unit 220 (or the edge sheet unit 221 , the first and second grid sheets) No tension is applied to the portions 223 and 225].

12 is a schematic diagram illustrating a process of sequentially attaching the mask 100 to the cell region CR according to an embodiment of the present invention.

After attaching one mask 100 to the frame 200 , the remaining masks 100 are sequentially matched to the remaining mask cells C, and the process of attaching the mask 100 to the frame 200 may be repeated. The remaining masks 100 may be sequentially matched to the remaining mask cells C, and the temperature of the process region may be controlled to the first temperature and the second temperature during the attachment process. Since the mask 100 already attached to the frame 200 can suggest the reference position, the time in the process of sequentially matching the remaining masks 100 to the cell region CR and checking the alignment state is significantly reduced. There are advantages to being In addition, the pixel position accuracy (PPA) between the mask 100 attached to one mask cell area and the mask 100 attached to the neighboring mask cell area does not exceed 3 μm, so that the alignment is clear. There is an advantage in that a mask for forming an OLED pixel can be provided.

13 is a schematic diagram illustrating a process of lowering (LT) the temperature of the process region after attaching the mask 100 to the cell region CR of the frame 200 according to an embodiment of the present invention.

Next, referring to FIG. 13 , the temperature of the process region may be lowered (LT) to a second temperature. The “second temperature” may mean a temperature lower than the first temperature. Considering that the first temperature is about 25°C to 60°C, the second temperature may be about 20°C to 30°C on the assumption that it is lower than the first temperature, and preferably, the second temperature may be room temperature. The temperature drop of the process region may be performed by installing a cooling means in the chamber, installing a cooling means around the process zone, or naturally cooling to room temperature.

When the temperature of the process region is lowered (LT) to the second temperature, the mask 100 may be thermally contracted by a predetermined length. The mask 100 may be isotropically heat-shrinkable along all lateral directions. However, since the mask 100 is fixedly connected to the frame 200 (or, the mask cell sheet unit 220 ) by welding, the heat shrinkage of the mask 100 is self-tensive to the surrounding mask cell sheet unit 220 . (TS) will be approved. The mask 100 may be attached to the frame 200 more taut by the application of the self-tensile TS of the mask 100 .

In addition, since the temperature of the process region is lowered (LT) to the second temperature after each mask 100 is attached to the corresponding mask cell region CR, all the masks 100 are subjected to thermal contraction at the same time to cause the frame The problem that 200 is deformed or that the alignment error of the patterns P increases can be prevented. More specifically, even if the tension TS is applied to the mask cell sheet part 220 , since the plurality of masks 100 apply the tension TS in opposite directions to each other, the force is canceled and the mask cell sheet part At 220, no deformation occurs. For example, the first grid sheet part 223 between the mask 100 attached to the CR11 cell area and the mask 100 attached to the CR12 cell area moves to the right of the mask 100 attached to the CR11 cell area. The applied tension TS and the tension TS acting in the left direction of the mask 100 attached to the CR12 cell region may be offset. Thus, the frame 200 (or the mask cell sheet part 220 ) due to the tension TS is deformed to be minimized, so that the alignment error of the mask 100 (or the mask pattern P) can be minimized. there is this

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

Referring to FIG. 14 , the OLED pixel deposition apparatus 1000 includes a magnet plate 300 in which a magnet 310 is accommodated, a coolant line 350 is disposed, and an organic material source 600 from a lower portion of the magnet plate 300 . ) and a deposition source supply unit 500 for supplying the .

A target substrate 900 such as glass on which the organic source 600 is deposited may be interposed between the magnet plate 300 and the source deposition unit 500 . The frame-integrated masks 100 and 200 [or FMMs] that allow the organic material source 600 to be deposited for each pixel may be disposed in close contact with or very close to each other on the target substrate 900 . The magnet 310 may generate a magnetic field and may be in close contact with the target substrate 900 by the magnetic field.

The deposition source supply unit 500 may supply the organic material source 600 while reciprocating left and right paths, and the organic material sources 600 supplied from the deposition source supply unit 500 may include patterns P formed on the frame-integrated masks 100 and 200 . ) and may be deposited on one side of the target substrate 900 . The deposited organic material source 600 passing through the pattern P of the frame-integrated masks 100 and 200 may act as the pixel 700 of the OLED.

In order to prevent non-uniform deposition of the pixel 700 due to the shadow effect, the pattern of the frame-integrated masks 100 and 200 may be inclined (S) (or formed in a tapered shape (S)). . Since the organic material sources 600 passing through the pattern diagonally along the inclined surface may also contribute to the formation of the pixel 700 , the pixel 700 may be deposited to have a uniform thickness as a whole.

Since the mask 100 is attached and fixed to the frame 200 at a first temperature higher than the pixel deposition process temperature, even if the process temperature for pixel deposition is increased, the position of the mask pattern P has little effect, and the mask The PPA between 100 and the mask 100 adjacent thereto may be maintained so as not to exceed 3 μm.

Although the present invention has been illustrated and described with reference to preferred embodiments as described above, it is not limited to the above-described embodiments and is not limited to the above-described embodiments, and various methods can be obtained by those of ordinary skill in the art to which the present invention pertains within the scope of the present invention. Transformation and change are possible. Such modifications and variations are intended to fall within the scope of the present invention and the appended claims.

60: vacuum transfer unit
70: lower support
90: mask loading unit
91: depression
92: transfer unit
93: laser penetration hole
95: heating unit
100: mask
110: mask film
200: frame
210: border frame portion
220: mask cell sheet portion
221: border sheet portion
223: first grid sheet portion
225: second grid sheet portion
1000: OLED pixel deposition device
C: cell, mask cell
CR: mask cell area
DM: dummy, mask dummy
ET: Raise the temperature of the process region to the first temperature
L: laser
LT: lowering the temperature of the process zone to the second temperature
R: Hollow area of the border frame part
P: mask pattern
TS: tension
VH: vacuum hole
W: Weld
WB: Weld Bead

Claims (29)

A transport system for a mask for forming an OLED pixel that loads and transports a mask in a process of integrally forming a mask and a frame supporting the mask, comprising:
a mask loading unit capable of adsorbing and loading one surface of the mask; and
Transfer unit that moves and flips the mask loading unit
including,
A transport system for a mask, wherein a laser passage hole is formed in a portion of the mask loading portion corresponding to the welding portion of the mask. According to claim 1,
The mask loading unit has a flat plate shape, and a plurality of vacuum holes are formed on one surface corresponding to the mask. According to claim 1,
A transport system for a mask, wherein a depression is formed at the edge of the mask loading part. 4. The method of claim 3,
The mask loading part is formed with a larger area than the mask,
When the mask is loaded into the mask loading unit, at least an edge of the mask protrudes outside the depression. According to claim 1,
The mask loading unit includes a heating unit. delete delete delete A method of manufacturing a frame-integrated mask in which at least one mask and a frame supporting the mask are integrally formed, the method comprising:
(a) loading one surface of the mask by adsorbing it to the mask loading unit;
(b) loading a mask loading unit on a frame having at least one mask cell region so that the mask corresponds to the mask cell region of the frame; and
(c) attaching the mask to the frame by irradiating a laser to the welding part of the mask
including,
A method of manufacturing a frame-integrated mask, wherein a laser passage hole is formed in a portion of the mask loading portion corresponding to the welding portion of the mask. delete delete 10. The method of claim 9,
The mask loading part has a flat plate shape, and a plurality of vacuum holes are formed on one surface corresponding to the mask,
In step (a), suction pressure is applied to one surface of the mask in a plurality of vacuum holes to adsorb the mask onto the mask loading unit, a method of manufacturing a frame-integrated mask. 13. The method of claim 12,
(a) step,
(a1) adsorbing at least two sides of the mask by the vacuum transfer unit; and
(a2) loading by adsorbing one surface of the mask to the mask loading unit by moving the vacuum transfer unit
Including, a method of manufacturing a frame-integrated mask. 14. The method of claim 13,
In step (a1), or, in step (a2),
A method of manufacturing a frame-integrated mask in which the vacuum transfer unit pulls the adsorbed mask outward to flatten the mask. 10. The method of claim 9,
A depression is formed at the edge of the mask loading part,
In step (b), when the mask is loaded in the mask loading unit, at least an edge of the mask protrudes to the outside of the depression, the method of manufacturing a frame-integrated mask. delete delete delete delete 10. The method of claim 9,
raising the temperature of the process region including the frame to a first temperature before or after the mask corresponds to the mask cell region;
A method of manufacturing a frame-integrated mask, wherein the temperature of a process region including the frame is lowered to a second temperature after the mask is adhered to the frame. delete delete delete delete delete delete delete delete delete

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