碲锌镉垂直布里奇曼法晶体生长过程固液界面的演化

计算模拟了半导体材料碲锌镉垂直布里奇曼法单晶体生长过程，以等温线图展示了固液界面形状的演化，分析了温度梯度和坩埚移动速率对固液界面形状以及晶体内组分偏析的影响。计算结果表明在凝固的初始段，固液界面的凹陷深度较大，随后有较大幅度的减小。整个凝固过程中固液界面的凹陷深度值有一定的波动性。提高温度梯度、降低坩埚移动速率均能有效地减小固液界面的凹陷，改善晶体的径向组分偏析。

Evolution of Solid-liquid Interface of CdZnTe Crystal Growth by Vertical Bridgman Method

It was simulated CdZnTe single crystal growth process with vertical Bridgman method. The evolution of the solid-liquid interface was illustrated by temperature contour graphs. The influences were investigated of the temperature gradient of the furnace and the crucible withdrawal rate, on the solid-liquid interface concavity and the solute segregation of CdZnTe crystal. It was shown that the interface concavity is rather large at the beginning of the solidification, decreases in a great deal later. Moreover, the interface concavity presents a small fluctuation in the whole growth process. Both the increase of the temperature gradient and the decrease of the growth rate result in a large decrease of the solid-liquid interface concavity and an extraordinary improvement of the radial solute segregation of the crystal. The radial solute segregation of the crystal could even become zero in some parts of the crystal.