勾形磁场下重力水平和温度梯度对CdZnTe分离结晶生长的影响

为了了解勾形磁场下相关参数对CdZnTe晶体生长的影响,利用有限元法对坩埚内的热量和动量传递过程进行了全局数值模拟。分析了不同的磁场强度下重力水平、壁面温度梯度对CdZnTe晶体生长过程的影响。结果表明：重力水平存在1个临界值,此时CdZnTe熔体内最大流函数最小,流动最弱。随着温度梯度逐渐增大,熔体内最大流函数也逐渐增大,熔体的流动越来越强,不利于晶体稳定生长。通过施加勾形磁场,能有效抑制熔体内的流动,有利于晶体的稳定生长,为地面条件下制备大尺寸CdZnTe晶体创造了条件。

Effects of Gravity Level and Temperature Gradient on CdZnTe Detached Solidification Growth under Cusp Magnetic Field

In order to clarify the effects of parameters on the growth quality of CdZnTe crystal in a cusp magnetic field,the global simulation analyses for heat and momentum transfers in a crucible was carried out using a finite-element method.The effects of gravity level,temperature gradient at different magnetic field intensities on the CdZnTe crystal growth were analyzed.The results showed that the gravity level had a critical value when the maximum stream function of CdZnTe melt was the minimum and there was the weaket melt flow.The maximum stream function and the melt flow increased with the temperature gradient increasing,resulting in an unstable crystal growth.The melt flow is suppressed by applying a cusp magnetic field,which favors the crystal steady growth and sets stage for the growth of large size CdZnTe crystal on the ground.