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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

  • Received : 2015.11.18
  • Accepted : 2015.12.04
  • Published : 2015.12.31

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.

Keywords

Sapphire;Thermal stress;Vertical Bridgman;Crystal growth;FEM

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