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CN-122006984-A - Coating method for improving rotation MURA of TFT-LCD color filter

CN122006984ACN 122006984 ACN122006984 ACN 122006984ACN-122006984-A

Abstract

The invention discloses a coating method for improving a rotating MURA of a TFT-LCD color filter, which comprises the following steps of preparing photoresist, namely providing photoresist with viscosity of 2.8-3.2 cP, and spin-coating the photoresist on the surface of a glass substrate at a spin speed N, wherein the spin speed N is cooperated with the photoresist, and the rotation speed reduction amplitude of the spin speed N relative to the original spin speed N0 is controlled within a range of 50-100 rpm. Therefore, the rotation speed of coating is synchronously reduced while the viscosity of the photoresist is reduced, so that the photoresist is matched with the rotation speed of coating in a coordinated manner, the viscosity resistance of the glue solution can be reduced, the excessive stretching effect of centrifugal force is weakened, the formation of film thickness gradients is avoided, the defects of light and dark stripes of rotary MURA are greatly reduced, the reject ratio of products is reduced, meanwhile, the film thickness uniformity can be improved without modifying the existing equipment, the stability of subsequent procedures is guaranteed, and the manufacturing cost is reduced.

Inventors

  • FANG JINBO
  • HE HAISHAN
  • HUANG JIANWEI
  • LIU SEN
  • ZHANG SEFENG

Assignees

  • 信利（惠州）智能显示有限公司

Dates

Publication Date
20260512
Application Date
20260326

Claims (10)

  1. 1. The coating method for improving the rotation MURA of the TFT-LCD color filter is characterized by comprising the following steps of: preparing photoresist, namely providing the photoresist with the viscosity of 2.8-3.2 cP; And (3) spin coating, namely dripping the photoresist on the surface of the glass substrate, and spin coating at a rotation speed N, wherein the rotation speed N is cooperated with the photoresist, and the rotation speed reduction amplitude of the rotation speed N relative to the original rotation speed N 0 is controlled within the range of 50 rpm-100 rpm.
  2. 2. The method of claim 1, wherein the original rotation speed N 0 is 300rpm to 500rpm, and the rotation speed N is 200rpm to 450rpm.
  3. 3. The method of claim 2, wherein the original rotational speed N 0 is 350rpm, the rotational speed N is reduced from the original rotational speed N 0 to 280rpm, and the photoresist adhesion is 3.0cP.
  4. 4. The method of claim 1, further comprising the step of, prior to the spin-coating step: And (3) preprocessing the substrate, namely cleaning and drying the glass substrate.
  5. 5. The method of claim 4, wherein in the step of pre-treating the substrate: Washing the glass substrate by adopting a water washing mode; the drying temperature is 110 ℃ and the drying time is 130s.
  6. 6. The method of claim 1 or 5, further comprising the steps of, after the spin-coating step: And (3) performing a curing treatment on the photoresist coated on the glass substrate to form a photoresist film layer.
  7. 7. The coating method for improving the rotation MURA of a TFT-LCD color filter according to claim 6, wherein in said curing step: the heat curing temperature was 230℃and the heat curing time was 30min.
  8. 8. The method for improving a TFT-LCD color filter rotation MURA according to claim 6, characterized in that after the curing treatment step, the method further comprises the steps of: And (3) detecting and verifying, namely detecting the thickness uniformity of the photoresist film layer on the glass substrate.
  9. 9. The method of claim 8, wherein in the step of detecting and verifying: The thickness of the photoresist film layer on the glass substrate is measured by adopting a film thickness meter, 9 measuring points are selected to collect thickness data of the photoresist film layer, and the film thickness uniformity of the photoresist film layer is calculated according to the following formula: (max-min)/(max+min)×100%; wherein max is the maximum value of the thickness of the photoresist film layer in 9 measuring points, and min is the minimum value of the thickness of the photoresist film layer in 9 measuring points.
  10. 10. The coating method for improving the rotation of a TFT-LCD color filter MURA according to claim 1, the method is characterized in that the photoresist is any one of RGB photoresist.

Description

Coating method for improving rotation MURA of TFT-LCD color filter Technical Field The invention relates to the technical field of display, in particular to a coating method for improving rotation MURA of a TFT-LCD color filter. Background In the manufacturing process of a TFT-LCD Color Filter (CF), the RGB photoresist coating of the color filter is one of the core processes, and a spin coating method is generally adopted in the industry to realize the uniform coating of the photoresist at present, namely, the photoresist is uniformly distributed on the surface of a glass substrate through the centrifugal force generated by high-speed rotation. In the spin coating process, due to unreasonable matching of photoresist glue and rotational speed, concentric circles or radial film thickness unevenness of photoresist glue solution on the surface of a substrate is easily formed, so that a rotation MURA defect is generated, and the defects are manifested as annular or radial uneven brightness during panel display, and the display image quality and the product yield are directly affected. The traditional coating process generally adopts photoresist with higher viscosity, and is matched with a fixed rotating speed to carry out coating, and the photoresist is not uniformly centrifugally spread due to poor matching between the photoresist and the rotating speed, so that the uniformity of the film thickness is poor, and the reject ratio of the rotating MURA is high. In addition, simply adjusting the viscosity or simply adjusting the rotational speed cannot fundamentally improve the rotational MURA defect, and it is difficult to meet the demand for a sufficient yield. In view of the above, a coating method for improving the rotation MURA of a TFT-LCD color filter is proposed. Disclosure of Invention The invention aims to overcome at least one defect in the prior art and provide a coating method for improving the rotation MURA of a TFT-LCD color filter, which improves the film thickness uniformity of a photoresist film layer by cooperatively adapting the photoresist adhesive and the rotation speed of the rotation coating, thereby realizing effective inhibition of the rotation MURA defect and improving the production yield. The aim of the invention is realized by the following technical scheme: The coating method for improving the rotation MURA of the TFT-LCD color filter is characterized by comprising the following steps of: preparing photoresist, namely providing the photoresist with the viscosity of 2.8-3.2 cP; And (3) spin coating, namely dripping the photoresist on the surface of the glass substrate, and spin coating at a rotation speed N, wherein the rotation speed N is cooperated with the photoresist, and the rotation speed reduction amplitude of the rotation speed N relative to the original rotation speed N 0 is controlled within the range of 50 rpm-100 rpm. In one embodiment, the original rotation speed N 0 is 300rpm to 500rpm, and the rotation speed N is 200rpm to 450rpm. In one embodiment, the raw rotational speed N 0 is 350rpm, the rotational speed N is reduced from the raw rotational speed N 0 to 280rpm, and the photoresist is 3.0cP. In one embodiment, before the spin coating step, the method further comprises the steps of: And (3) preprocessing the substrate, namely cleaning and drying the glass substrate. In one embodiment, in the substrate pretreatment step: Washing the glass substrate by adopting a water washing mode; the drying temperature is 110 ℃ and the drying time is 130s. In one embodiment, after the spin coating step, the method further comprises the steps of: And (3) performing a curing treatment on the photoresist coated on the glass substrate to form a photoresist film layer. In one embodiment, in the curing process step: the heat curing temperature was 230℃and the heat curing time was 30min. In one embodiment, after the curing treatment step, the method further comprises the steps of: And (3) detecting and verifying, namely detecting the thickness uniformity of the photoresist film layer on the glass substrate. In one embodiment, in the detection verification step: The thickness of the photoresist film layer on the glass substrate is measured by adopting a film thickness meter, 9 measuring points are selected to collect thickness data of the photoresist film layer, and the film thickness uniformity of the photoresist film layer is calculated according to the following formula: (max-min)/(max+min)×100%; wherein max is the maximum value of the thickness of the photoresist film layer in 9 measuring points, and min is the minimum value of the thickness of the photoresist film layer in 9 measuring points. In one embodiment, the photoresist is any one of RGB photoresists. Compared with the prior art, the invention has at least the following advantages: 1. According to the coating method for improving the rotation MURA of the TFT-LCD color filter, the traditional process method of matching the 4cP high