Temperature Analysis of Electrostatic Chuck for Cryogenic Etch Equipment

극저온 식각장비용 정전척 쿨링 패스 온도 분포 해석

  • Du, Hyeon Cheol (Department of Electronics Engineering, Myongji University) ;
  • Hong, Sang Jeen (Department of Electronics Engineering, Myongji University)
  • 두현철 (명지대학교 전자공학과) ;
  • 홍상진 (명지대학교 전자공학과)
  • Received : 2021.06.08
  • Accepted : 2021.06.21
  • Published : 2021.06.30

Abstract

As the size of semiconductor devices decreases, the etching pattern becomes very narrow and a deep high aspect ratio process becomes important. The cryogenic etching process enables high aspect ratio etching by suppressing the chemical reaction of reactive ions on the sidewall while maintaining the process temperature of -100℃. ESC is an important part for temperature control in cryogenic etching equipment. Through the cooling path inside the ESC, liquid nitrogen is used as cooling water to create a cryogenic environment. And since the ESC directly contacts the wafer, it affects the temperature uniformity of the wafer. The temperature uniformity of the wafer is closely related to the yield. In this study, the cooling path was designed and analyzed so that the wafer could have a uniform temperature distribution. The optimal cooling path conditions were obtained through the analysis of the shape of the cooling path and the change in the speed of the coolant. Through this study, by designing ESC with optimal temperature uniformity, it can be expected to maximize wafer yield in mass production and further contribute to miniaturization and high performance of semiconductor devices.

Keywords

Acknowledgement

연구는 경기도 소재부품장비자립화 지원사업 (No. AICT-006-T1)의 지원으로 수행되었으며, 산업통상자원부 반도체소재부품장비 전문인력양성사업단의 학술적 토론과 자문에 감사드립니다.

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