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CN-122013105-A - Metal mask and manufacturing method thereof

CN122013105ACN 122013105 ACN122013105 ACN 122013105ACN-122013105-A

Abstract

The invention discloses a metal mask and a manufacturing method of the metal mask, wherein the metal mask is used for vapor deposition of an organic light-emitting layer of an OLED device, the metal mask comprises a mask body, a plurality of mask holes are formed in the mask body, the mask body comprises a first surface and a second surface which are opposite, the mask holes penetrate through the first surface and the second surface, a first opening is formed in the first surface by the mask holes, a second opening is formed in the second surface by the mask holes, and the ratio of the aperture of the first opening to the aperture of the second opening is 1-1.5. The metal mask plate has the characteristics of high tensile strength and high resolution.

Inventors

  • LIU HUANLONG
  • CHEN DINGGUO
  • HUA DEMING
  • WANG XING
  • YANG TAO
  • XU ZONGYI

Assignees

  • 宁波寰采星科技股份有限公司

Dates

Publication Date
20260512
Application Date
20260408

Claims (10)

  1. 1. The metal mask plate is used for vapor deposition of an organic light-emitting layer of an OLED device and comprises a mask plate body, a plurality of mask holes are formed in the mask plate body, the mask plate body comprises a first surface and a second surface which are opposite, and the mask holes penetrate through the first surface and the second surface.
  2. 2. The metal reticle of claim 1, wherein the reticle aperture forms a step on an inner wall proximate the second surface, the step being located between the second opening and a middle portion of the reticle aperture, and the step having a diameter greater than an aperture of the second opening.
  3. 3. The metal reticle of claim 2, wherein a difference between a diameter of the step portion and a pore diameter of the second opening is less than or equal to 0.5 μm, and an axial height of the step portion is less than or equal to 0.5 μm.
  4. 4. The metal mask according to claim 2, wherein the aperture of the second opening is between 5 and 20 μm.
  5. 5. The metal reticle of any one of claims 1-4, wherein the resolution of the metal reticle is between 600 and 1500 ppi.
  6. 6. The metal mask according to any one of claims 1 to 4, wherein the thickness of the metal mask is less than or equal to 20. Mu.m.
  7. 7. A method of manufacturing a metal mask blank according to any one of claims 1 to 6, comprising the steps of: placing a substrate in electroforming solution for electrodeposition, and forming a first foil on the substrate; separating the first foil from the substrate; Performing heat treatment on the first foil to obtain a second foil, wherein the proportion of the body-centered cubic structure of the second foil does not exceed a set proportion; And etching the second foil to obtain the metal mask.
  8. 8. The method of claim 7, wherein the second foil has an average coefficient of thermal expansion of less than or equal to 2 ppm/K at 20-200 ℃.
  9. 9. The method of manufacturing according to claim 7, wherein heat treating the first foil comprises applying a set tension to the first foil, the set tension being in the range of 5-1500N/mm2; Heating the first foil with the set tension to a set temperature in a protective atmosphere, and keeping each place of the first foil at the set temperature for a set time, wherein the set temperature is 300-600 ℃, and the set time is 0.5-10 min.
  10. 10. The manufacturing method according to claim 9, wherein in the heat treatment step, the first foil is heated to the set temperature by a heat treatment furnace provided with a foil inlet and a foil outlet, wherein the first foil is in a protective atmosphere and has an oxygen content of less than 100ppm by controlling an unreeling device and a reeling device so that a moving speed of the first foil in the heat treatment furnace is 1-10 m/min.

Description

Metal mask and manufacturing method thereof Technical Field The invention relates to the technical field of mask manufacturing, in particular to a metal mask and a manufacturing method of the metal mask. Background Among commercial mass production methods of Organic LIGHT EMITTING (OLED) light emitting diodes, vapor deposition is currently the dominant technology, and the vapor deposition process requires the use of a precision metal mask (FMM, fine Metal Mask) to deposit the light emitting layer of the OLED device, and the quality of the precision metal mask determines the quality of the OLED screen manufactured by the method. The resolution of the current AMOLED (active matrix organic light emitting diode) products is limited to below 600ppi, the size of the display screen is 5-17 inches (folding screen), and the size of the corresponding red, green and blue sub-pixels to be manufactured is about 30-100 μm. In order to manufacture higher resolution screen products, higher resolution precision metal reticles must be introduced. In order to improve the resolution ratio of the precise metal mask, the reduction of the spacing between adjacent apertures is mostly realized, and the reduction of the spacing between the adjacent apertures has higher requirements on the thickness and the thermal expansion coefficient of the foil. However, the existing precise metal mask plate has the problem that the foil used for manufacturing cannot meet the requirement of manufacturing the high-resolution mask plate. Disclosure of Invention The invention aims to provide a metal mask plate and a manufacturing method thereof, which have the advantages of low thermal expansion coefficient, better flatness and high resolution. In order to achieve the above object, a first aspect of the present invention discloses a metal mask for vapor deposition of an organic light emitting layer of an OLED device, including a mask body, on which a plurality of mask holes are formed, the mask body including a first surface and a second surface opposite to each other, the mask holes penetrating the first surface and the second surface, the mask holes forming first openings on the first surface, the mask holes forming second openings on the second surface, and a ratio of an aperture of the first openings to an aperture of the second openings being between 1 and 1.5. When the apertures of the first and second openings are close, the pixel density of the first surface can be increased without affecting the pixel density of the second surface, the distance between adjacent apertures can be greatly reduced, and ppi (pixels per inch) can be increased. Optionally, the mask hole forms a step portion on a side close to the second surface, the diameter of the step portion is larger than the aperture of the second opening, and the step portion is close to the second surface relative to the second opening. Optionally, a difference between a diameter of the step portion and a diameter of the second opening is less than or equal to 0.5 μm, and a height of the step portion is less than or equal to 0.5 μm. The smaller the height of the step, the smaller the shadow area generated in the evaporation process, and the mura defect (the defect of uneven local brightness or chromaticity in the screen display process) generated by the screen can be reduced. Optionally, the second opening has a pore size of between 5 and 20 μm. Optionally, the resolution of the metal mask is 600-1500 ppi. Optionally, the thickness of the metal mask is less than or equal to 20 μm. The thickness of the metal mask plate is smaller than or equal to 20 mu m, and the upper limit of the FMM product ppi can be improved. The second aspect of the invention discloses a method for manufacturing a metal mask, which comprises the following steps: placing a substrate in electroforming solution for electrodeposition, and forming a first foil on the substrate; separating the first foil from the substrate; Performing heat treatment on the first foil to obtain a second foil, wherein the proportion of the body-centered cubic structure of the second foil does not exceed a set proportion; And etching the second foil to obtain the metal mask. The first foil is formed on the substrate by electrodeposition, and a deposition platform is provided for the first foil, so that the first foil can be shaped as a thin sheet. In the electrodeposition step and the separation step, stress is accumulated in the first foil, and the subsequent processing flow is affected by no treatment, which is specifically shown as reducing the service life of the first foil or enabling the first foil to be deformed more easily, and the thermal expansion coefficient of the first foil is larger, so that the first foil needs to be subjected to heat treatment. In the heat treatment step, the first foil is heated to a certain temperature to change the lattice structure in the first foil so as to promote the uneven stress to be balanced, meanwhil