物性参数对硅单晶Czochralski生长过程的影响

Effects of thermophysical properties on silicon single crystal Czochraski growth processes

为了了解硅单晶C zochra lsk i(C z)法生长时物性参数对熔体流动和氧传输过程的影响,利用有限元法对炉内的传递过程进行了全局数值模拟,假定熔体和气相中的流动都为准稳态轴对称层流,熔体为不可压缩流体,C z炉外壁温度维持恒定。结果表明:熔体的导热系数及发射率对熔体流动、加热器功率、结晶界面形状、晶体内轴向温度梯度和氧浓度有重要影响,而熔体的密度、黏度系数及熔解热对硅单晶C z法生长过程影响较小。

In order to understand the effects of thermophysical properties on the silicon melt flow and oxygen transport in a silicon Czochralski （Cz） furnace, a set of global numerical simulations was conducted using the finite-element method. It was assumed that the flow was axisymmetric laminar in both the melt and the gas, the melt was incompressible and a constant temperature was imposed on the outer wall of the Cz furnace. The results show that thermal conductivity and emissivity of melt have significant effects on the flow pattern, heater power, shape of the crystal/melt, axial temperature gradient in the melt and oxygen concentration. However, effects of the density, viscosity of the melt and heat of fusion on silicon single crystal Czochralski growth processes are smaller.