Correction method for defective hole patterns of metal masks for OLED light emitting element deposition

Abstract

A method for correcting a defective hole pattern of a metal mask for OLED light emitting element deposition is provided, the method comprising: melting a metal sheet with a first laser to fill a defective hole pattern of the metal mask; and processing the filled defective hole pattern with a second laser to correct the defective hole pattern to a normal hole pattern.

Description

[Technical Field]

[0001] The present invention relates to a method for correcting a defective hole pattern of a metal mask for evaporating an OLED light emitting element. [Background technology]

[0002] Recently, the demand for light emitting diode (LED) displays has increased compared to that for liquid crystal displays (LCDs). Accordingly, it is necessary for the light emitting diode (LED) displays to uniformly deposit light emitting elements, which are essential components for emitting light, on a substrate.

[0003] One method for depositing light-emitting elements is to deposit the light-emitting elements through a metal mask, in which pattern holes are formed in the metal mask, and the light-emitting elements are deposited through the pattern holes.

[0004] In the past, if the size of one of the multiple pattern holes in a metal mask was small, an etching / laser processing method was further applied to correct it so that it matched the size of the other pattern holes. However, if the size of a defective hole pattern was larger than the other hole patterns (normal hole patterns), for example, if two or more normal hole patterns were connected to each other to form an open hole shape, resulting in a large hole size, or if there was an open metal area between normal hole patterns, it was also treated as a defect. In this case, there was no way to correct the size of the hole pattern, and the metal mask itself had to be discarded.

[0005] The background art of the present invention is described in the following Patent Document 1 and the like. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Korean Patent Registration No. 10-2380239 Summary of the Invention [Problem to be solved by the invention]

[0007] An object of the present invention is to provide a method for correcting a defective hole pattern of a metal mask for deposition of an OLED light emitting element, which can correct only the defective hole pattern to a normal hole pattern without discarding the deposition mask for an OLED light emitting element on which the defective hole pattern is formed, thereby eliminating the trouble of having to re-manufacture all hole patterns and improving the yield of mask manufacturing.

[0008] Another object of the present invention is to provide a method for correcting a defective hole pattern of a metal mask for deposition of an OLED light emitting element, which does not require discarding the mask and eliminates the hassle of having to re-manufacture all hole patterns when the size of a defective hole pattern is larger than that of a normal hole pattern, for example, when two or more normal hole patterns are connected to each other to form an open hole shape, resulting in a larger hole size, or when there is a defect such as an open metal region between normal hole patterns.

[0009] It is still another object of the present invention to provide a method for correcting a defective hole pattern of a metal mask for deposition of an OLED light emitting element, which improves correction efficiency and accuracy when correcting a defective hole pattern. [Means for solving the problem]

[0010] In order to solve the above technical problems, the present invention provides a method for correcting a defective hole pattern of a metal mask for depositing an OLED light emitting element.

[0011] 1. A method for correcting a defective hole pattern in a metal mask for OLED light emitting element deposition includes melting a metal sheet with a first laser to fill a defective hole pattern in the metal mask, and processing the filled defective hole pattern with a second laser to correct the defective hole pattern to a normal hole pattern.

[0012] In 2.1, the method may include the steps of: positioning the metal sheet on one side of the metal mask on which at least the defective hole pattern is formed (step 1); irradiating a region of the metal sheet corresponding to the defective hole pattern with the first laser to fill the defective hole pattern with molten material from the metal sheet (step 2); and irradiating a second laser to the molten material from the metal sheet within the defective hole pattern to pattern it, thereby correcting the defective hole pattern to a normal hole pattern (step 3).

[0013] In 3.2, the method may further include, between step 2 and step 3, a step (step 4) of irradiating a region of the metal sheet that does not correspond to the defective hole pattern with the second laser to cut the metal sheet.

[0014] In 4.1-3, the defective hole pattern may be a pattern having a hole larger in size than the normal hole pattern.

[0015] In 5.4, the defective hole pattern may be a pattern in which two or more normal hole patterns are connected to each other, or a pattern in which metal areas between the normal hole patterns are removed.

[0016] In 6.1-5, the thickness of the metal thin plate may be 3 to 50 μm.

[0017] In 7.1-6, the metal sheet may be made of iron, nickel, silver, gold, copper, aluminum, cobalt, chromium, tungsten, molybdenum, or an alloy of two or more of these.

[0018] In 8.1-7, the first laser may be a continuous wave laser.

[0019] In 9.1-8, the second laser may be a laser having a pulse width of picoseconds or less. [Effects of the Invention]

[0020] The present invention provides a method for correcting a defective hole pattern of a metal mask for deposition of an OLED light emitting element, which can improve the yield of mask manufacturing by correcting only the defective hole pattern to a normal hole pattern without discarding the deposition mask for an OLED light emitting element on which the defective hole pattern is formed, thereby eliminating the trouble of having to remanufacture all hole patterns.

[0021] The present invention provides a method for correcting a defective hole pattern of a metal mask for deposition of OLED light emitting elements, which eliminates the need to re-manufacture all hole patterns without discarding the mask when the size of a defective hole pattern is larger than that of a normal hole pattern, for example, when two or more normal hole patterns are connected to each other to form an open hole shape and the hole size is increased, or when there is a defect such as an open metal area between normal hole patterns.

[0022] The present invention provides a method for correcting a defective hole pattern of a metal mask for deposition of an OLED light emitting device, which improves correction efficiency and accuracy when correcting a defective hole pattern. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1a is a plan view of a metal mask in which only a plurality of normal hole patterns are formed, and FIG. 1b is a cross-sectional view of the metal mask in which only a plurality of normal hole patterns are formed, taken along the line I-II of FIG. 1a. [Figure 2] FIG. 2a is a plan view of a metal mask in which a defective hole pattern is formed, and FIG. 2b is a cross-sectional view of the metal mask in which a defective hole pattern is formed, taken along the line I-II of FIG. 2a. [Figure 3]2 is a flowchart illustrating a method for repairing a defective hole pattern of a metal mask for depositing an OLED light emitting device according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0024] The present invention will be described in more detail below with reference to the accompanying drawings. However, the following drawings are provided merely to facilitate understanding of the present invention, and the present invention is not limited to the following drawings. Furthermore, the shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings are merely examples, and the present invention is not limited to the details shown.

[0025] Throughout the specification, the same reference numerals refer to the same elements. Furthermore, when describing the present invention, if it is determined that a detailed description of related prior art would unnecessarily obscure the gist of the present invention, the detailed description will be omitted.

[0026] When "comprises," "has," "consists," and the like are used herein, other parts may be added unless "only" is used. When an element is expressed in the singular, it also includes the plural unless otherwise expressly stated.

[0027] When interpreting elements, they are interpreted as including a margin of error even if there is no explicit statement otherwise.

[0028] In this specification, the numerical range "a to b" is defined as "≧a and ≦b".

[0029] The present invention relates to a method for correcting a pattern of a deposition mask for an OLED light emitting element.

[0030] The present invention eliminates the need to remanufacture the entire mask when a defective hole pattern is formed on a deposition mask for an OLED light emitting device by correcting only the defective hole pattern to a normal hole pattern without discarding the mask. The present invention also improves correction efficiency and accuracy by enabling the defective hole pattern to have substantially the same shape and size as the normal hole pattern. In particular, the present invention eliminates the need to remanufacture the entire hole pattern without discarding the mask when the defective hole pattern is larger than the normal hole pattern, for example, when two or more normal hole patterns are connected to each other to form an open hole shape and the hole size is larger than the normal hole pattern, or when there is a defect in the metal area between the normal hole patterns that is open.

[0031] The deposition mask for OLED light-emitting elements is a mask made of a metal material and has a plurality of hole patterns formed therein. The deposition mask for OLED light-emitting elements is a mask used in the organic material deposition process during the OLED manufacturing process. For example, the deposition mask for OLED light-emitting elements is used for depositing organic materials for the light-emitting layer. The deposition mask for OLED light-emitting elements allows OLED light-emitting elements, for example, red, green, and blue light-emitting elements, to pass through the plurality of hole patterns, thereby depositing the light-emitting elements in the desired position and shape.

[0032] FIG. 1a is a plan view of a metal mask in which only a plurality of normal hole patterns are formed, and FIG. 1b is a cross-sectional view of the metal mask in which only a plurality of normal hole patterns are formed.

[0033] 1a and 1b, a plurality of normal hole patterns 11 are formed on a metal mask 10. The size and shape of the normal hole patterns 11 are not particularly limited and may vary depending on the screen size of a light emitting device display device in which the light emitting device is mounted.

[0034] Meanwhile, the metal mask is formed by etching a metal plate. The etching may be dry etching or wet etching. During etching, a defective hole pattern may be formed in at least a portion of the metal mask. Here, the defective hole pattern is a pattern in which the holes are larger than those of a normal hole pattern, and may be a pattern in which two or more normal hole patterns are connected to each other (also known as an open defective hole pattern), or a defective hole pattern in which the metal area between normal hole patterns is removed (open). If light-emitting devices are deposited through such a defective hole pattern, there is a high probability that light-emitting devices with a relatively larger size than those of the normal hole pattern will be deposited, resulting in non-uniform light emission between the light-emitting devices.

[0035] FIG. 2a is a plan view of a metal mask in which a defective hole pattern is formed, and FIG. 2b is a cross-sectional view of the metal mask in which a defective hole pattern is formed.

[0036] 2a and 2b, a metal mask 10 is formed with a plurality of normal hole patterns 11 as well as a defective hole pattern 12. The defective hole pattern 12 may have a form in which two normal hole patterns are connected to each other, i.e., a form of an open defective hole pattern, but is not limited thereto.

[0037] The present invention relates to a method for correcting a defective hole pattern formed on a metal mask into a normal hole pattern by using a laser.

[0038] The method for correcting a defective hole pattern of a metal mask for deposition of an OLED light emitting element according to the present invention includes melting a metal sheet with a first laser to fill a defective hole pattern of the metal mask, and processing the filled defective hole pattern with a second laser to correct the defective hole pattern to a normal hole pattern.

[0039] In one embodiment, the method includes the steps of: positioning the metal sheet on one side of the metal mask on which at least the defective hole pattern is formed (step 1); irradiating a region of the metal sheet corresponding to the defective hole pattern with the first laser to fill the defective hole pattern with molten material from the metal sheet (step 2); and irradiating a second laser to the molten material from the metal sheet within the defective hole pattern to pattern it, thereby correcting the defective hole pattern to a normal hole pattern (step 3).

[0040] The method may further include, between steps 2 and 3, a step (step 4) of irradiating a region of the metal sheet that does not correspond to the defective hole pattern with the second laser to cut the metal sheet.

[0041] The method of the present invention will now be described with reference to FIG.

[0042] The presence and location of defective hole patterns 12 on the metal mask for deposition of the OLED light emitting device on which a plurality of normal hole patterns 11 are formed is checked. This can be checked visually or using a microscope.

[0043] A metal sheet 20 is placed in an area including at least the defective hole pattern 12. The metal sheet 20 is then melted to fill the defective hole pattern 12. The metal mask is formed by etching the metal sheet. The etching may be dry etching or wet etching.

[0044] The metal sheet 20 may be formed of the same or a different material than the metal mask. The metal sheet 20 may have a thermal expansion coefficient that is substantially the same as or different from that of the metal mask. The thermal expansion coefficients of the metal mask and the metal sheet are important when performing the method of the present invention. As will be described below, the metal sheet is melted by the first laser to fill in the defective hole pattern. The "thermal expansion coefficient" can be measured by a conventional method known to those skilled in the art.

[0045] For example, the thin metal plate 20 may be in the form of a plate made of iron, nickel, silver, gold, copper, aluminum, cobalt, chromium, tungsten, molybdenum, or an alloy of two or more of these metals.

[0046] The metal thin plate 20 may have a thickness of 3 to 50 μm, preferably 10 to 30 μm. This range allows the defective hole pattern to be sufficiently filled, and the desired uniform normal hole pattern can be formed by the subsequent laser.

[0047] The width of the metal sheet 20 may be the same as or larger than the width of the defective hole pattern 12 .

[0048] Thereafter, a first laser is irradiated onto an area of ​​the metal sheet 20 corresponding to the defective hole pattern 12, and the defective hole pattern 12 is welded with the molten material of the metal sheet. One feature of the present invention is that the first laser is used to melt the metal sheet.

[0049] The first laser may be a laser having a pulse width greater than a nanosecond, such as a continuous wave laser (CW laser). A continuous wave laser has a smaller spot size than commonly used welding lasers, allowing for improved correction efficiency and accuracy. The medium of the first laser may be a solid, fiber, CO2, or the like, and, unlike commonly used industrial welding lasers, the spot size is 0.2 mm or less. This allows for improved correction efficiency and accuracy when correcting defective hole patterns.

[0050] Thereafter, a second laser is irradiated onto an area of ​​the metal sheet 20 that does not correspond to the defective hole pattern 12 to cut the metal sheet 20. This removes the remaining welded metal sheet, making it easier to pattern the metal sheet with the second laser later.

[0051] The second laser may be a laser having a pulse width of picoseconds or less, for example, a picosecond laser.

[0052] The wavelength of the second laser can be selected depending on the material of the metal sheet. The second laser can correct the defective hole pattern to a normal hole pattern by patterning the melted material of the metal sheet within the defective hole pattern. Alternatively, the second laser can be irradiated to an area of ​​the metal sheet that does not correspond to the defective hole pattern to cut the metal sheet. This can improve the correction efficiency and accuracy when correcting the defective hole pattern.

[0053] The present invention has been described above with reference to the preferred embodiments. Those skilled in the art will understand that the present invention can be embodied in various modified forms without departing from the essential characteristics of the present invention. Therefore, the disclosed embodiments should be considered from an illustrative rather than a restrictive perspective. The scope of the present invention is defined by the claims, not the foregoing description, and all variations within the scope of the claims should be construed as being within the scope of the present invention.

[0054] (Addendum) (Appendix 1) Melting the thin metal plate with a first laser to fill the defective hole pattern of the metal mask; correcting the defective hole pattern to a normal hole pattern by processing the filled defective hole pattern with a second laser; Including, A method for correcting defective hole patterns in metal masks for OLED light-emitting element deposition.

[0055] (Appendix 2) The method comprises: Step 1: Positioning the thin metal plate on one side of the metal mask on which at least the defective hole pattern is formed; Step 2: irradiating a region of the metal sheet corresponding to the defective hole pattern with the first laser to fill the defective hole pattern with the melted material of the metal sheet; a step (step 3) of correcting the defective hole pattern to a normal hole pattern by irradiating the molten material of the thin metal plate within the defective hole pattern with a second laser to form a pattern; Including, 2. A method for correcting a defective hole pattern of a metal mask for OLED light-emitting element deposition according to claim 1.

[0056] (Appendix 3) The method further includes, between step 2 and step 3, a step (step 4) of irradiating a region of the thin metal plate that does not correspond to the defective hole pattern with the second laser to cut the thin metal plate. 3. A method for correcting a defective hole pattern of a metal mask for OLED light-emitting element deposition according to claim 2.

[0057] (Appendix 4) the defective hole pattern has a hole having a larger size than the normal hole pattern; 2. A method for correcting a defective hole pattern of a metal mask for OLED light-emitting element deposition according to claim 1.

[0058] (Appendix 5) The defective hole pattern is a pattern in which two or more normal hole patterns are connected to each other or a pattern in which a metal region between the normal hole patterns is removed. 5. A method for correcting a defective hole pattern of a metal mask for vapor deposition of an OLED light-emitting element according to claim 4.

[0059] (Appendix 6) The thickness of the metal thin plate is 3 to 50 μm. 2. A method for correcting a defective hole pattern of a metal mask for OLED light-emitting element deposition according to claim 1.

[0060] (Appendix 7) The metal sheet is made of iron, nickel, silver, gold, copper, aluminum, cobalt, chromium, tungsten, molybdenum, or an alloy of two or more of these. 2. A method for correcting a defective hole pattern of a metal mask for OLED light-emitting element deposition according to claim 1.

[0061] (Appendix 8) The first laser is a continuous wave laser. 2. A method for correcting a defective hole pattern of a metal mask for OLED light-emitting element deposition according to claim 1.

[0062] (Appendix 9) The second laser is a laser having a pulse width of picoseconds or less. 2. A method for correcting a defective hole pattern of a metal mask for OLED light-emitting element deposition according to claim 1.

Claims

1. Melting the thin metal plate with a first laser to fill the defective hole pattern of the metal mask; correcting the defective hole pattern to a normal hole pattern by processing the filled defective hole pattern with a second laser; Including, A method for correcting defective hole patterns in metal masks for OLED light-emitting element deposition.

2. The method comprises: Step 1: positioning the thin metal plate on one side of the metal mask on which at least the defective hole pattern is formed; Step 2: irradiating a region of the metal sheet corresponding to the defective hole pattern with the first laser to fill the defective hole pattern with molten material of the metal sheet; Step 3: correcting the defective hole pattern to a normal hole pattern by irradiating the molten material of the thin metal plate within the defective hole pattern with a second laser to form a pattern; Including, 2. The method for correcting a defective hole pattern of a metal mask for vapor deposition of an OLED light emitting element according to claim 1.

3. The method further includes, between step 2 and step 3, a step (step 4) of irradiating a region of the thin metal plate that does not correspond to the defective hole pattern with the second laser to cut the thin metal plate.

3. The method for correcting a defective hole pattern of a metal mask for vapor deposition of an OLED light emitting element according to claim 2.

4. the defective hole pattern has a hole having a larger size than the normal hole pattern; 2. The method for correcting a defective hole pattern of a metal mask for vapor deposition of an OLED light emitting element according to claim 1.

5. The defective hole pattern is a pattern in which two or more normal hole patterns are connected to each other or a pattern in which a metal region between the normal hole patterns is removed.

5. The method for correcting a defective hole pattern of a metal mask for vapor deposition of an OLED light emitting element according to claim 4.

6. The thickness of the metal sheet is 3 to 50 μm.

2. The method for correcting a defective hole pattern of a metal mask for vapor deposition of an OLED light emitting element according to claim 1.

7. The metal thin plate is made of iron, nickel, silver, gold, copper, aluminum, cobalt, chromium, tungsten, molybdenum, or an alloy of two or more of these.

2. The method for correcting a defective hole pattern of a metal mask for vapor deposition of an OLED light emitting element according to claim 1.

8. The first laser is a continuous wave laser.

2. The method for correcting a defective hole pattern of a metal mask for vapor deposition of an OLED light emitting element according to claim 1.

9. The second laser is a laser having a pulse width of picoseconds or less.

2. The method for correcting a defective hole pattern of a metal mask for vapor deposition of an OLED light emitting element according to claim 1.

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