Evolutions of Both Temperature Field and Convection Field During GaInSb THM and VB Crystal Growths and Influences of Temperature Gradient

Abstract

III-V semiconductor compound crystals are widely used in the advanced infrared detectors and lasers etc. The traveling heater method (THM) and the vertical Bridgman method (VB) are two important methods to grow high-quality, especially low dislocation density bulk single crystals, in which the furnace temperature gradient G_TH, usually plays a key role determining the dislocation density. This work simulates numerically GaInSb crystal growths with both THM and VB, displaying the evolutions of both the temperature field inside the crucible domain and the flow field in the melt in detail, investigating the influences of G_TH on the temperature and the flow fields, especially on the temperature gradient at the front of crystal growth interface and its shape. The results show that both of them are more dependent on G_TH during THM crystal growth than during VB one. Furthermore, this work focuses on the impact of the mushy zone in the front of growth interface during the ternary compounds’ crystal growth, which has been almost always ignored in the previous numerical simulation works.