Journal of the Korean Crystal Growth and Crystal Technology (한국결정성장학회지)

The Korea Association of Crystal Growth (한국결정성장학회)
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Fundamental studies on thermosolutal convection in mercurous bromide(Hg2Br2) physical vapor transport processes

브로민화 수은(I)(Hg2Br2) 물리적 증착공정에서 온도농도대류의 기초연구

  • Geug Tae Kim (Department of Chemical Engineering, Hannam University) ;
  • Moo Hyun Kwon (Department of Energy and Electrical Engineering, Woosuk University)
  • 김극태 (한남대학교 화학공학과) ;
  • 권무현 (우석대학교 에너지전기공학과)
  • Received : 2023.05.12
  • Accepted : 2023.06.09
  • Published : 2023.06.30
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Abstract

During the Hg2Br2 physical vapor transport process, with increasing the partial pressure of component B, PB from 40 Torr to 200 Torr, a unicellular convective flow structures move from the crystal growth region to the center region in the vapor phase. The boundary layer flow is dominant for PB = 40 Torr, and the core region flow is dominant for PB = 200 Torr. The flow in the vapor phase shows a three-dimensional convective flow structure with a single cell (unicellular) for PB = 40 Torr and 200 Torr, exhibits an asymmetrical flow with respect to the x, y central axis under the horizontally oriented configuration with an aspect ratio (length-to-width) of 3 and linear conducting walls. The critical temperature difference between the source and crystal region is about 30 K. The total molar flux of Hg2Br2 increases with the temperature difference until the total molar flux reaches the critical value. At the critical total molar flux, the total molar flux abruptly decreases.

브로민화 수은(I)(Hg2Br2) 물리적 증착법 공정에서 구성요소 B의 분압, PB를 40 Torr에서 200 Torr로 증가시켰을 때 1개의 셀(unicell)이 결정성장영역에서 기체상 공간의 중심으로 이동함을 보여주고 있다. PB = 40 Torr에서는 경계층 흐름이 지배적이고, PB = 200 Torr에서는 코어영역흐름(core region)을 보이고 있다. 고려되는 물리적 증착법 공정에서 PB = 40 Torr와 PB = 200 Torr에서 1개(single)의 셀(cell) 형태로 3차원의 유동의 흐름과 x, y 직교 중심축에 대하여 비대칭 유동흐름을 나타내고 있다. 소스와 결정 영역 사이의 임계 온도차는 약 30 K입니다. Hg2Br2의 총 몰 플럭스는 임계값에 도달할 때까지 온도차에 따라 증가한다. 임계 총 몰 플럭스에서 총 몰 플럭스는 갑자기 감소한다.

Keywords

Acknowledgement

본 연구는 2022년도 한남대학교 학술연구비(과제번호: 2022A017)의 지원을 받아 수행되었습니다.

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