Characteristics of single/poly crystalline silicon etching by$Ar^+$ ion laser for MEMS applications

MEMS 응용을 위한 $Ar^+$ 이온 레이저에 의한 단결정/다결정 실리콘 식각 특성

  • Lee, Hyun-Ki (Dept.of Electrical Engineering, Graduate School of Korea University) ;
  • Han, Seung-Oh (Dept.of Electrical Engineering, Graduate School of Korea University) ;
  • Park, Jung-Ho (Dept.of Electrical Engineering, Engineering College, Korea University) ;
  • Lee, Cheon (Dept.of Electric Engineering, Inha University)
  • 이현기 (고려대 대학원 전기공학과) ;
  • 한승오 (고려대 대학원 전기공학과) ;
  • 박정호 (고려대 공대 전기공학과) ;
  • 이천 (인하대 공대 전기공학과)
  • Published : 1999.05.01

Abstract

In this study, $Ar^+$ ion laser etching process of single/poly-crystalline Si with $CCl_2F_2$ gas is investigated for MEMS applications. In general, laser direct etching process is useful in microelectronic process, fabrication of micro sensors and actuators, rapid prototyping, and complementary processing because of the advantages of 3D micromachining, local etching/deposition process, and maskless process with high resolution. In this study, a pyrolytic method, in which $CCl_2F_2$ gasetches molten Si by the focused laser, was used. In order to analyze the temperature profile of Si by the focused laser, the 3D heat conduction equation was analytically solved. In order to investigate the process parameters dependence of etching characteristics, laser power, $CCl_2F_2$ gas pressure, and scanning speed were varied and the experimental results were observed by SEM. The aspect ratio was measured in multiple scanning and the simple 3D structure was fabricated. In addition, the etching characteristics of $6\mum$ thick poly-crystalline Si on the insulator was investigated to obtain flat bottom and vertical side wall for MEMS applications.

Keywords

MEMS;3D micromachining;Laser direct etching;Silicon

References

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