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

The Korea Association of Crystal Growth (한국결정성장학회)
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Analysis of thermal stress through finite element analysis during vertical Bridgman crystal growth of 2 inch sapphire

유한요소해석법을 이용한 2 inch 사파이어 vertical Bridgman 결정성장 공정 열응력 해석

  • Kim, Jae Hak (Department of Materials Science and Engineering, Pusan National University) ;
  • Lee, Wook Jin (Dongnam Regional Division, Korea Institute of Industrial Technology) ;
  • Park, Yong Ho (Department of Materials Science and Engineering, Pusan National University) ;
  • Lee, Young Cheol (Dongnam Regional Division, Korea Institute of Industrial Technology)
  • 김재학 (부산대학교 공과대학 재료공학부) ;
  • 이욱진 (한국생산기술연구원 동남지역본부) ;
  • 박용호 (부산대학교 공과대학 재료공학부) ;
  • 이영철 (한국생산기술연구원 동남지역본부)
  • Received : 2015.11.18
  • Accepted : 2015.12.04
  • Published : 2015.12.31
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Abstract

Sapphire single crystals have been highlighted for epitaxial of gallium nitride films in high-power laser and light emitting diode industries. Among the many crystal growth methods, vertical Bridgman process is an excellent commercial method for growing high quality sapphire crystals with c-axis. In this study, the thermally induced stress in Sapphire during the vertical Bridgman crystal growth process was investigated using a finite element model. A vertical Bridgman process of 2-inch Sapphire was considered for the model. The effects of vertical and transverse temperature gradients on the thermal stress during the process were discussed based on the finite element analysis results.

사파이어 단결정은 GaN계 화합물 증착이 용이하여 고휘도 LED(Light Emitting Diode), 고출력 레이저 산업 등에서 크게 각광받고 있다. 다양한 사파이어 단결정 제조공법 중 vertical Bridgman 공법은 고품질의 사파이어를 c-축 방향으로 성장시킬 수 있는 공법이며 상업적으로 적용이 검토되고 있다. 본 연구에서는 2인치 사파이어 성장 vertical Bridgman 공정에서 성장시 온도구배에 의해 발생하는 열응력을 유한요소 모델을 통해 분석하였다. 이를 통해 성장시 수직, 수평방향으로의 온도구배가 사파이어 결정의 열응력과 결함발생에 미치는 영향을 검토하였다.

Keywords

References

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