Effect of the Ingot Cooling on the Grown-in Defects in Silicon Czochralski Growth

Abstract

208 mm diameter single crystals are grown by Czochralski method with different growing conditions, and the effects of the ingot cooling on point defect behavior and the shape of the crystal–melt interface are experimentally investigated. In order to obtain various cooling rates of the ingot, cooling-water jacket is changed with various surface conditions, which are different emissivities of the material, and various melt gaps are applied in the experiments, where melt gap is defined as the distance from heat shield to the melt free-surface. The crystal–melt interface becomes more concave (convex to the crystal) and the critical pulling speed for defect-free crystal increases with increasing cooling rate of the ingot.