AMOLED 제조공정에 사용되는 Fine Metal Mask 용 얇은 Invar 합금의 진동자를 이용한 펨토초 레이저 응용 홀 드릴링

Application of femtosecond laser hole drilling with vibration for thin Invar alloy using fine metal mask in AMOLED manufacturing process

  • 최원석 (한국기계연구원 나노공정연구실) ;
  • 김훈영 (한국기계연구원 나노공정연구실) ;
  • 신영관 (한국기계연구원 나노공정연구실) ;
  • 최준하 (한국기계연구원 나노공정연구실) ;
  • 장원석 (한국기계연구원 나노공정연구실) ;
  • 김재구 (한국기계연구원 나노공정연구실) ;
  • 조성학 (한국기계연구원 나노공정연구실) ;
  • 최두선 (한국기계연구원 나노공정연구실)
  • 투고 : 2020.09.16
  • 심사 : 2020.09.30
  • 발행 : 2020.09.30

초록

One of display trends today is development of high pixel density. To get high PPI, a small size of pixel must be developed. RGB pixel is arranged by evaporation process which determines pixel size. Normally, a fine metal mask (FMM; Invar alloy) has been used for evaporation process and it has advantages such as good strength, and low thermal expansion coefficient at low temperature. A FMM has been manufactured by chemical etching which has limitation to controlling the pattern shape and size. One of alternative method for patterning FMM is laser micromachining. Femtosecond laser is normally considered to improve those disadvantages for laser micromachining process due to such short pulse duration. In this paper, a femtosecond laser drilling for thickness of 16 ㎛ FMM is examined. Additionally, we introduce experimental results for controlling taper angle of hole by vibration module adapted in laser system. We used Ti:Sapphire based femtosecond laser with attenuating optics, co-axial illumination, vision system, 3-axis linear stage and vibration module. By controlling vibration amplitude, entrance and exit diameters are controllable. Using vibrating objective lens, we can control taper angle when femtosecond laser hole drilling by moving focusing point. The larger amplitude of vibration we control, the smaller taper angle will be carried out.

키워드

참고문헌

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