摘要
本文采用四阶龙格-库塔法对地面分离结晶生长CdZnTe晶体过程中气液界面形状及熔体-坩埚气缝宽度进行了模拟,讨论了α_e+θ_c<180°和α_e+θ_c> 180°时影响气液界面形状及气缝宽度的控制因素。采用线性回归方法对模拟结果进行了分析,得到了地面条件下分离结晶稳定生长的影响因素和控制条件。即:只有满足熔体冷-热端气压调节与结晶速率成线性变化,才能维持稳定的分离结晶。
The gas-liquid interface shape and gas gap width of detached solidification for CdZnTe on the ground were simulated by the fourth-order Runge-Kutta method. The influence factors of gas-liquid interface shape and gas gap width were discussed respectively when α_c+ θ_c< 180° and α_c+ θ_c> 180°.The simulation results were analyzed by linear regression method,while the influencing factors and control conditions for stable detached solidification for CdZnTe under ground conditions were obtained. In order to maintain a stable detached solidification process,it is necessary to satisfy the law of linear change between the amount of air pressure regulation at the cold and hot ends as well as the crystallization rate.
引文
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