Numerical simulations considering effects of thermal stress and impurities on the behavior of intrinsic point defects in Si crystal growing by Cz method

Abstract

  We developed a numerical simulation model of intrinsic point defect dynamics considering the effects of the dopant concentration and thermal stress in a silicon crystal growing by the Czochralski (Cz) method. The thermal equilibrium concentration of the intrinsic point defects (vacancy, V, and self-interstitial Si atom, I) was determined as a function of the incorporated dopant concentration and the thermal stress in a growing Si crystal, which was obtained through ab-initio calculations. Furthermore, point defect dynamics in the crystal were solved within a two-dimensional axisymmetric global heat and mass transport model by considering the thermal stress and the incorporation of a dopant using segregation for Si crystal growth by the Cz method. The numerical simulations showed that the formation and the distribution of intrinsic point defects significantly depend on the incorporated dopant concentration and the thermal stress in a growing Si crystal.