Computer Simulation of Concentration Distribution of Intrinsic Point Defect Valid for All Pulling Conditions in Large-Diameter Czochralski Si Crystal Growth

Abstract

To explain and engineer intrinsic point defect behavior in large-diameter single crystal Si grown using the Czochralski (CZ) method, a unified model valid for all pulling processes, crystal resistivities, and electrically inactive impurity concentrations that couples the effects of thermal stress, dopants, and interstitial oxygen (Oi) atoms is needed. We determined the thermal equilibrium concentration of intrinsic point defects (vacancy V and self-interstitial Si I) in CZ-Si crystal as functions of thermal stresses, type and concentration of dopant, and the concentration of Oi atoms. Global heat transfer during crystal growth in a puller was simulated using STR Group's CGSim software package. A visual distribution of V and I concentrations inside a growing doped and thermally stressed Si ingot is very useful for improving the quality of large-diameter CZ-Si crystals.