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Characterization of X-ray Emitted in the Ion Implantation Process of Semiconductor Operations

반도체 제조 이온주입 공정의 이온 임플란타 장치에서 엑스레이 발생 특성

  • Dong-Uk Park (Department of Environmental Health, Korea National Open University) ;
  • Kyung Ehi Zoh (Department of Environmental Health, Graduate School of Public Health, Seoul National University) ;
  • Soyeon Kim (Changwon Fatima Hospital) ;
  • Seunghee Lee (Department of Environmental Health, Korea National Open University) ;
  • Eun Kyo Jeong (Department of Industrial Safety and Health, Osan University)
  • 박동욱 (한국방송대학교 보건환경학과) ;
  • 조경이 (서울대학교 보건대학원 환경보건학과) ;
  • 김소연 (창원파티마병원) ;
  • 이승희 (한국방송대학교 보건환경학과) ;
  • 정은교 (오산대학교 산업안전보건과)
  • Received : 2023.10.06
  • Accepted : 2023.12.14
  • Published : 2023.12.31

Abstract

Objectives: The aims of this study are to investigate how X-rays are emitted to surrounding parts during the ion implantation process, to analyze these emissions in relation to the properties of the ion implanter equipment, and to estimate the resulting exposure dose. Eight ion implanters equipped with high-voltage electrical systems were selected for this study. Methods: We monitored X-ray emissions at three locations outside of the ion implanters: the accelerator equipped with a high-voltage energy generator, the impurity ion source, and the beam line. We used a Personal Portable Dose Rate and Survey Meter to monitor real-time X-ray levels. The SX-2R probe, an X-ray Features probe designed for use with the RadiagemTM meter, was also utilized to monitor lower ranges of X-ray emissions. The counts per second (CPS) measured by the meter were estimated and then converted to a radiation dose (𝜇Sv/hr) based on a validated calibration graph between CPS and μGy/hr. Results: X-rays from seven ion implanters were consistently detected in high-voltage accelerator gaps, regardless of their proximity. X-rays specifically emanated from three ion implanters situated in the ion box gap and were also found in the beam lines of two ion implanters. The intensity of these X-rays did not show a clear pattern relative to the devices' age and electric properties, and notably, it decreased as the distance from the device increased. Conclusions: In conclusion, every gap, in which three components of the ion implanter devices were divided, was found to be insufficiently shielded against X-ray emissions, even though the exposure levels were not estimated to be higher than the threshold.

Keywords

Acknowledgement

이 논문은 2023년도 한국방송통신대학교 지원을 받아 작성된 것으로 이에 감사를 드립니다.

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