用升华法生长SiC晶体的一种新颖的坩埚设计

本文提出一个用PVT法生长SiC晶体的坩埚的新颖设计.分析了生长腔中有无锥形档板对腔内及籽晶温度场的影响;比较了档板取不同厚度时SiC粉源升华面和籽晶表面的温度分布.得出了在腔内增设档板后晶体生长面的温度更趋均匀的结论;获取了随着档板厚度的增加,腔内的轴向温度梯度随之增加,但同时晶体生长面的温度也会降低的设计原则.根据计算结果,选取档板厚度等于2mm为优化参数.

A Novel Design of Crucible for Sublimation Growth of SiC Single Crystals

A novel design of crucible is firstly proposed in this paper.The effects of the cone-shaped bar in the growth chamber on the evolution of the temperature fields of the growth chamber and the seed are discussed,respectively.The influences of different thicknesses of the bar on the temperature distribution at SiC source powder and seed single crystal surfaces are also investigated systematically.The calculations suggest that the radial temperature field of the growing crystal became homogenous by setting up the cone-shaped baffle in the growth cell.The axial temperature gradient is increased with the increase of the baffle thickness,but the growing temperature of SiC crystals falls down at the same time.By the simulation,we can conclude that the optimal baffle thickness is about 2mm,which is relatively favorable to improve the quality and to increase the yield of growing crystal.