Numerical and experimental investigation of effect of oxygen concentration on grown-in defects in a Czochralski silicon single crystal

Abstract

Grown-in defect-free wafers are required in silicon semiconductor devices. A point defect concentration simulation was performed along with an experimental investigation, demonstrating a wide range of oxygen concentrations from 1.6 × 1017 to 9.1 × 1017 cm−3 in crystals. Thus, the effect of oxygen atoms in a Czochralski silicon single crystal with grown-in defect behavior was revealed. Consequently, the increasing vacancy concentration trapped by the oxygen atom (oxygen coefficient) was estimated as 4.61 × 10−5 per oxygen atom. Previously, for obtaining the oxygen coefficient, a regression equation assuming thermal equilibrium concentrations of vacancy (V) and interstitial Si (I) was applied to the experimental results. However, the interface shape, thermal stress, and hot-zone structure of the experimental level needed to be arranged; this affected the grown-in defect behavior. In this study, the oxygen coefficient and thermal equilibrium concentration of V and I were determined uniquely without arranging the situations experimental level.