Development of Wafer Cleaning Equipment Using Nano Bubble and Megasonic Ultrasound

나노 버블과 메가소닉 초음파를 이용한 반도체 웨이퍼 세정장치 개발

  • 김노유 (한국기술교육대학교 메카트로닉스공학부) ;
  • 이상훈 (알티자동화(주) 기술연구소) ;
  • 윤상 (이앤에이치(주)) ;
  • 정용래 (씨티아이코리아(주) 기술연구소)
  • Received : 2023.11.14
  • Accepted : 2023.12.12
  • Published : 2023.12.31

Abstract

This paper describes a hybrid cleaning method of silicon wafer combining nano-bubble and ultrasound to remove sub-micron particles and contaminants with minimal damage to the wafer surface. In the megasonic cleaning process of semiconductor manufacturing, the cavitation induced by ultrasound can oscillate and collapse violently often with re-entrant jet formation leading to surface damage. The smaller size of cavitation bubbles leads to more stable oscillations with more thermal and viscous damping, thus to less erosive surface cleaning. In this study, ultrasonic energy was applied to the wafer surface in the DI water to excite nano-bubbles at resonance to remove contaminant particles from the surface. A patented nano-bubble generator was developed for the generation of nano-bubbles with concentration of 1×109 bubbles/ml and nominal nano-bubble diameter of 150 nm. Ultrasonic nano-bubble technology improved a contaminant removal efficiency more than 97% for artificial nano-sized particles of alumina and Latex with significant reduction in cleaning time without damage to the wafer surface.

Keywords

Acknowledgement

이 논문은 2023년도 교육부 산학연협력 고도화 지원사업 (LINC 3.0)의 산학연구과제(LINC3.0-2023-31) 및 2023년 중소벤처기업부 Tech-Bridge활용 상용화 기술개발사업 (과제번호: G21002170331), 그리고 한국기술교육대학교 교육연구진흥과제 지원에 의하여 연구되었으며 이에 감사드립니다.

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