Journal of Sensor Science and Technology (센서학회지)

The Korean Sensors Society (한국센서학회)
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Hydrogen Fluoride Vapor Etching of SiO2 Sacrificial Layer with Single Etch Hole

단일 식각 홀을 갖는 SiO2 희생층의 불화수소 증기 식각

  • Chayeong Kim (Advanced Mechatronics R&D Group, Korea Institute of Industrial Technology) ;
  • Eunsik Noh (Advanced Mechatronics R&D Group, Korea Institute of Industrial Technology) ;
  • Kumjae Shin (Advanced Mechatronics R&D Group, Korea Institute of Industrial Technology) ;
  • Wonkyu Moon (Department of Mechanical Engineering, Pohang University of Science and Technology)
  • 김차영 (한국생산기술연구원 첨단메카트로닉스 연구그룹) ;
  • 노은식 (한국생산기술연구원 첨단메카트로닉스 연구그룹) ;
  • 신금재 (한국생산기술연구원 첨단메카트로닉스 연구그룹) ;
  • 문원규 (포항공과대학교 기계공학과)
  • Received : 2023.09.11
  • Accepted : 2023.09.27
  • Published : 2023.09.30
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Abstract

This study experimentally verified the etch rate of the SiO2 sacrificial layer etching process with a single etch hole using vapor-phase hydrogen fluoride (VHF) etching. To fabricate small-sized polysilicon etch holes, both circular and triangular pattern masks were employed. Etch holes were fabricated in the polysilicon thin film on the SiO2 sacrificial layer, and VHF etching was performed to release the polysilicon thin film. The lateral etch rate was measured for varying etch hole sizes and sacrificial layer thicknesses. Based on the measured results, we obtained an approximate equation for the etch rate as a function of the etch hole size and sacrificial layer thickness. The etch rates obtained in this study can be utilized to minimize structural damage caused by incomplete or excessive etching in sacrificial layer processes. In addition, the results of this study provide insights for optimizing sacrificial layer etching and properly designing the size and spacing of the etch holes. In the future, further research will be conducted to explore the formation of structures using chemical vapor deposition (CVD) processes to simultaneously seal etch hole and prevent adhesion owing to polysilicon film vibration.

Keywords

Acknowledgement

이 논문은 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(No. 2021R1F1A1064046). 샘플 제작 과정에 도움을 준 영남대학교 미래자동차공학과 최주헌 군에게 감사를 전합니다.

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