Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Improvement of CMP and Cleaning Process of Large Size OLED LTPS Thin Film Using Oscar Type Polisher

Oscar형 연마기를 이용한 대면적 OLED용 LTPS 박막의 CMP 처리 및 세정 공정 개선

  • Received : 2022.11.17
  • Accepted : 2022.12.12
  • Published : 2022.12.31
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Abstract

We evaluated and developed a 6th generation large-size polisher in the type of face-up and Oscar. We removed the hillocks of the low temperature poly-silicon (LTPS) thin film with this polisher. The surface roughness of LTPS was lowered from 7.9 nm to 0.6 nm after CMP(chemical mechanical polishing). The thickness of the LTPS is measured through reflectance in real time during polishing, and the polishing process is completed according to this thickness. The within glass non-uniformity (WIGNU) was 6.2% and the glass-to-glass non-uniformity (GTGNU) was 2.5%, targeting the LTPS thickness of 400Å. In addition, the residual slurry after the CMP process was removed through the Core Flow PVA Brush and alkaline chemical.

Keywords

Acknowledgement

본 연구는 2021년도 중소벤처기업부의 창업성장기술개발사업 지원에 의한 연구임 [S3139319].

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