L-丙氨酸掺杂下ZTS晶体(100)面台阶动力学实时研究

In-situ Study on the Kinetics of Growth Steps on the (100) Faces of L-Alanine Doped ZTS Crystals

利用光学显微镜对L-丙氨酸掺杂下ZTS晶体(100)面台阶推移进行了实时观察。测量了不同掺杂浓度、过饱和度及生长温度下的台阶平均推移速度。实验结果表明:随掺杂浓度的增加,台阶平均推移速度先增加后减小,在掺杂浓度为2mol%时,台阶平均推移速度最大;而随过饱和度的增加,台阶平均推移速度线性增加。计算了台阶动力学系数与单台阶的活化能,得到掺杂后,台阶动力学系数增大,单台阶活化能减小。运用台阶动力学系数的定义,计算得到掺杂与未掺杂ZTS晶体台阶活化能的范围。同时用红外光谱实验分析了L-丙氨酸在ZTS晶体生长过程中进入晶格,进而影响台阶推移速度。

In-situ observation of movement process of steps on the（100） face of ZTS crystals under different doping concentration of L-alanine was investigated by using optical microscopy.The average displacement velocities of growth steps under different doping concentration of L-alanine,supersaturation and growth temperature were measured.Experimental results show that with the increase of additive concentration,additive lead to first an increase and then a decrease in the average displacement velocities,passing through a maximum under the condition of the doping concentration of 2mol% L-alanine.However,the average displacement velocities of growth steps increase linearly with the increase of supersaturation.Activation energy for single step and kinetic coefficient for steps were calculated.Under the condition of doping,kinetic coefficient for steps increases and activation energy for single step decreases.The scope of activation energy for steps of ZTS crystals was calculated under the condition of doping and without doping according to kinetic coefficient for steps definition.In the process of crystal growth,L-alanine could enter into ZTS crystal lattices and has an effect on the displacement velocity of steps,analyzed by Infrared spectra experiments