Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Thermal Deformation of Glass Backplane during Flash Lamp Crystallization Process of Amorphous Silicon

플래시 램프를 이용한 비정질 실리콘 결정화 공정에서의 유리기판 열변형

  • Kim, Dong-Hyun (Research Institute for Science and Technology, Hongik Univ.) ;
  • Kim, Byung-Kuk (Viatron Technologies, Suwon Industrial Complex) ;
  • Kim, Hyoung-June (Viatron Technologies, Suwon Industrial Complex) ;
  • Chung, Ha-Seung (Dept. of Mechanical and System Design Engineering, Hongik Univ.) ;
  • Park, Seung-Ho (Dept. of Mechanical and System Design Engineering, Hongik Univ.)
  • 김동현 (홍익대학교 과학기술연구소) ;
  • 김병국 ((주) 비아트론) ;
  • 김형준 ((주) 비아트론) ;
  • 정하승 (홍익대학교 기계시스템디자인공학과) ;
  • 박승호 (홍익대학교 기계시스템디자인공학과)
  • Received : 2012.06.07
  • Accepted : 2012.07.09
  • Published : 2012.10.01
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Abstract

The flash lamp annealing (FLA) process has been considered highly promising for manufacturing low-temperature polysilicon on large-scale backplanes. Based on a theoretical estimation, this study clarifies the critical mechanisms of glass backplane deformation during the FLA process. A simulation using a commercial FEM code with viscoelastic models shows that the local region, whose temperature is larger than the glass softening point, undergoes permanent structural shrinkage owing to stress relaxation. For larger backplanes (4th Gen), structural shrinkages and gravitational deflection are critical to deformation in the FLA process, resulting in an "M" shape; in smaller backplanes (0th Gen), the latter is negligible, resulting in a "U" shape.

플래시 램프 열처리(Flash lamp annealing, FLA) 공정은 저온폴리실리콘의 생산을 위한 기술로써 대면적 기판용 실리콘 결정화 기술로 기대 받고 있는 기술이다. 본 연구에서는 FLA 공정 중 기판에 발생하는 변형의 원인에 대하여 이론적인 해석과 이를 토대로 시뮬레이션을 수행하였다. 상용 FEM 해석프로그램에 고온에서의 유리의 점성에 대한 모델을 적용하여, 고온에서 유리의 구조적인 수축과 응력이완으로 인한 영구변형을 수치적으로 재현하였다. 0 세대 실험시편($2cm{\times}2cm$)의 경우 중력의 영향이 미미하여서, 실험 결과와 일치하는 'U'모양의 변형이 남는 것을 확인하였고, 4 세대 기판($74cm{\times}94cm$)의 경우 중력으로 인하여 'M'모양의 변형이 발생하는 것을 시뮬레이션하였다.

Keywords

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