Molecular dynamics simulation of oxygen in silicon melt

Abstract

Molecular dynamic simulation of an oxygen atom in silicon crystal and the melt was carried out to obtain the diffusion constants of oxygen in the melt. The simulation using mixed potential in the melt, in which an oxygen atom and 216 silicon atoms were taken into account has been carried out. Vibration frequencies of oxygen and vacancy–oxygen (V–O) pair in the crystal have been calculated. Calculated frequency of oxygen and V–O pair were 1000 and 820 cm −1, respectively, while the experimental results which were obtained from Fourier transform spectra of infrared absorption (FTIR) are 1100 and 830 cm −1, respectively. Oxygen diffusion constant was obtained in an elevated temperature of 1700 K. Calculated diffusion constant of oxygen in the melt was 1×10 −4 cm 2/s.