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CN-121995691-A - BIM mask preparation method for replacing HTM in FPD field

CN121995691ACN 121995691 ACN121995691 ACN 121995691ACN-121995691-A

Abstract

The application provides a preparation method of a BIM mask plate for replacing HTM in the field of FPD, which is applied to a one-step patterning forming process of a pixel definition layer PDL and a support column PS in OLED manufacturing, and comprises the steps of taking a binary mask plate BIM as a substrate, determining an opaque region and a full-transparent region of the mask plate, wherein the region corresponding to a PS structure is set as the opaque region, and the transmittance is 0%; setting the area corresponding to the PDL structure as a full-light-transmission area with the transmittance of 100%, additionally arranging a grating structure at the transition position between the light-tight area and the full-light-transmission area, and setting the adaptive process parameters according to the coating thickness of the photoresist, wherein the process parameters comprise exposure dose, development time, hard baking temperature and ultraviolet irradiation dose. The preparation method of the application realizes the PDL and PS one-time patterning effect which is completely the same as the HTM, greatly reduces the cost of the mask plate, and simultaneously maintains various advantages of the original HTM process.

Inventors

  • CHEN SHANTAO
  • YIN JINGWEN
  • ZHENG ZHENGUO

Assignees

  • 天津华大九天科技有限公司

Dates

Publication Date
20260508
Application Date
20260330

Claims (10)

  1. 1. A preparation method of BIM mask for replacing HTM in FPD field is applied to one-step patterning forming process of pixel definition layer PDL and support column PS in OLED manufacture, and comprises the following steps: The method comprises the steps of taking a binary mask BIM as a substrate, and determining an opaque region and a full-transparent region of the mask, wherein the region corresponding to a PS structure is set as the opaque region, the transmittance is 0%, and the region corresponding to a PDL structure is set as the full-transparent region, and the transmittance is 100%; A grating structure is additionally arranged at the transition position between the light-tight area and the full-light-transmission area; And setting adaptive process parameters according to the coating thickness of the photoresist, wherein the process parameters comprise exposure dose, development time, hard baking temperature and ultraviolet irradiation dose.
  2. 2. The method for preparing a BIM mask for replacing HTM in the FPD field according to claim 1, wherein the grating is of a slit structure, the line width and the distance of the grating are designed to be 0.5 to 0.7 times of the real resolution of a photoetching machine, and the width of the grating is adapted according to the characteristics of exposure equipment and photoresist materials used for manufacturing the FPD.
  3. 3. The method for preparing a BIM mask for replacing HTM in the FPD field according to claim 2, wherein the grating structure attenuates the incident light energy by using the optical interference effect of the slit to realize the gradient distribution of the transmittance between 0% and 100%, and the grating structure is disposed at the rest positions except the opaque region of 0% transmittance and the fully transparent region of 100% transmittance on the whole BIM mask.
  4. 4. The method for preparing a BIM mask for replacing HTM in FPD field according to claim 1, wherein the transmittance of the grating structure is 15%, so that the incident light passes through the mask to form a stepped light energy distribution of 0% in PS region, 15% in grating transition region and 100% in PDL region.
  5. 5. The method for preparing a BIM mask for replacing HTM in the FPD field according to claim 1, wherein the step of setting the adapted process parameters according to the coating thickness of the photoresist further comprises: the exposure dose and the development time are adjusted to achieve the target critical dimension of the photoresist according to the thickness of the photoresist; the hard baking temperature is the curing temperature of photoresist; the ultraviolet irradiation dose is selected according to the thickness of the photoresist and the material characteristics.
  6. 6. The method for preparing a BIM mask for replacing HTM in the FPD field according to claim 1, wherein the photoresist is photosensitive polyimide, a stepped outline shape is formed after exposure and development by the mask, wherein a reverse taper opening with a narrow upper part and a wide lower part is formed in a PDL area, and a columnar structure with a height of 1.5-2.0 μm is reserved in a PS area.
  7. 7. The preparation method of the BIM mask for replacing HTM in the FPD field according to claim 1, further comprising the steps of mounting the prepared BIM mask to an exposure machine, exposing an 8-Gen OLED substrate coated with photoresist for one time, performing development, hard baking and UV irradiation treatment after the exposure, and forming a stepped profile shape by the photoresist after the development, wherein a PS region keeps a columnar structure with a height of 1.8 mu m, a PDL region forms an inverted cone opening with a narrow upper part and a wide lower part, and the bottom is hydrophilic and the top is hydrophobic, so that the process requirements of OLED manufacturing are met.
  8. 8. A BIM mask for replacing HTM in the FPD field, which is characterized in that the BIM mask is prepared by the method for preparing the BIM mask for replacing HTM in the FPD field according to any one of claims 1 to 6.
  9. 9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor is configured to execute the computer program stored in the memory to implement the method for preparing a BIM mask for replacing an HTM in the FPD field according to any one of claims 1 to 6.
  10. 10. A computer readable storage medium having a computer program stored therein, wherein the computer program is loaded and executed by a processor to implement the FPD domain replacement HTM BIM reticle preparation method of any one of claims 1 to 6.

Description

BIM mask preparation method for replacing HTM in FPD field Technical Field The application relates to the technical field of advanced package design, in particular to a multi-layer layout connectivity checking method crossing EDA tools. The application relates to the technical field of flat panel display (FPD, flat Panel Display) manufacture, in particular to a preparation method of a BIM mask for replacing a halftone mask (HTM) in the field of FPD, which is suitable for a one-step graphical forming process of a Pixel Definition Layer (PDL) and a support column (PS) in OLED manufacture. Background In the OLED manufacturing process, the patterning preparation of the Pixel Defining Layer (PDL) and the support column (PS) is one of the core processes, and in the prior art, a halftone mask (HTM, halftone Mask) process is adopted to realize one-time patterning of the PDL and the PS, so that the patterning preparation replaces the complicated process of the traditional two-time coating and two masks, and becomes a mainstream process scheme. The core principle of the HTM process is that photosensitive polyimide (PSPI) is adopted as a molding material in both PDL and PS areas, the material is provided with photosensitive groups, solubility after exposure is different, and patterning of two layers can be simultaneously completed through one-time coating, one-time exposure and one-time development of the HTM mask without additional dry etching or wet etching steps. The PDL area is irradiated by a higher exposure dose and developed to form an inverted cone opening with a narrow upper part and a wide lower part, so that the bottom is hydrophilic to realize ink drop spreading, the top is hydrophobic to prevent overflow, the strict requirement of ink drop morphology in ink-jet printing is met, and the PS area is irradiated by a lower exposure dose or is subjected to mask local shading, is developed to retain a columnar structure with a height of 1.5-2.0 mu m, and is used for supporting a metal mask (FMM) in a subsequent evaporation link to prevent the mask from sinking and scratching PDL and an organic functional layer. Compared with the traditional process, the HTM process has the remarkable process simplification effect that the traditional process needs to sequentially finish organic resin coating, first mask exposure and development, dry etching, cleaning, inorganic layer coating, second mask secondary exposure and development, and two masks, two coatings and two dry etching are used in total, and the HTM process compresses the process into 'one coating + one mask + one development', so that equipment occupation is reduced by more than 30%, takt time is shortened by about 25%, and alignment errors and particle pollution risks are effectively reduced. In addition, the PDL/PS structure formed by the HTM process is high in compatibility, the reverse taper opening of the PDL in the ink-jet route can guide the RGB ink to be accurately filled, the PS column in the evaporation route can support the FMM, the mask sagging amount is ensured to be less than 5 mu m when large-size substrates with the size of 8-Gen or more are evaporated, and the color mixing problem is avoided. However, the existing HTM process has the core defects that the manufacturing cost of the HTM Mask is extremely high, the cost of each HTM Mask is about 100 ten thousand yuan, the cost of each common Binary Mask (BIM) is only 30 ten thousand yuan, and the high cost of the HTM Mask greatly increases the manufacturing total cost of the OLED product and becomes the cost bottleneck of large-scale production in the FPD industry, so that development of a Mask with low cost and a preparation method for replacing the HTM to realize the same process effect are needed. Disclosure of Invention In order to solve the defects of the prior art, the application aims to provide a preparation method of a BIM mask for replacing HTM in the FPD field, which is based on BIM, realizes the completely same PDL and PS one-time patterning effect as HTM through reasonable graphic design and process parameter matching, greatly reduces the cost of the mask, and simultaneously maintains various advantages of the original HTM process. In order to achieve the above object, the preparation method of BIM mask for replacing HTM in FPD field provided by the application is applied to one-step patterning forming process of pixel defining layer PDL and support column PS in OLED manufacture, and comprises the following steps: The method comprises the steps of taking a binary mask BIM as a substrate, and determining an opaque region and a full-transparent region of the mask, wherein the region corresponding to a PS structure is set as the opaque region, the transmittance is 0%, and the region corresponding to a PDL structure is set as the full-transparent region, and the transmittance is 100%; A grating structure is additionally arranged at the transition position between the light-tight area and