Formation Kinetics and Infrared Absorption of Carbon-Oxygen Complexes in Czochralski Silicon

The study of nucleation kinetics and infrared absorption measured at 8 K provides the models of nucleation reactions of carbon-oxygen complexes formed during annealing at 500°C and 650°C. We have, for the first time, found that the reduction ratio of interstitial oxygen in the 450–650°C range obeys the Johnson-Mehl-Avrami equation with a reaction rate constant expressed byk= 83.9 exp (-1.0 eV/kBT) cm-1. Nucleation at 650°C follows first-order kinetics, while that at 500°C follows third-order kinetics. The 1104-cm-1band due to carbon-oxygen pairs formed above 1000°C decreases throughout annealing at 650°C, whereas it increases upon annealing at 500°C for up to 64 h. Five bands appear at 1026, 1052, 1099, 1107.5 and 1112 cm-1, and their intensities increase throughout the annealing process at 500°C for up to 64 h and remain constant from 64 to 128 h, and decrease beyond 128 h. From these findings, carbon-oxygen complexes formed at 650°C and at 500°C are concluded to be Cs–Onwithn= 1, 2, 3, … and Cs–Oi–O2, respectively.