Variation of Effective Impurity Segregation Coefficient in Tellurium Grown under High Gravity

Abstract

Previous experimental results on tellurium crystal growth in a Bridgman configuration under normal and enhanced gravity (5 g, 10 g) were analyzed using a thermosolutal convection model. For the given processing conditions the calculated Rayleigh numbers are in the range for stable convection in the melt. We separated the contributions of impurity and intrinsic defects using the experimental electrical properties along the ingots. The shape of the charge carrier profile depended on the relationship between the impurity con-centration and the number of electrically active defects. It was shown that with steady convection, the gravity level affects the dynamics of intrinsic defect formation. The Hole mobility in ingots solidified at high gravity was lower than in the ingot solidified at 1 g.