Dislocation density analyses of GaAs bulk single crystal during growth process (effects of crystal anisotropy)

摘要

A computer code was developed for simulation of dislocation density in a bulk single crystal during the Czochralski growth process. In this computer code, the effects of crystal anisotropy such as theelastic constants and slip directions were approximately taken into account by averaging the Young's modulus, the Possion's modulus, the Poisson's ratio and the resolved shear stress along the azimuthal direction. Axisymmetric finite element analysis can be applied to quantitative estimation of dislocation density during single crystal growth process by using such averaging technique together with the Haasen-Alexander-Sumino model as a creep constitutive equation of a single crystal at elevated temperatures.