抄録
Solid phase epitaxy (SPE) of Si is one of the most fundamental processes in semiconductor fabrication techniques. Many experimental studies have been carried out for understanding the growth mechanism. However microscopic mechanism is not well understood. In this study, we investigated the effect of arsenic atoms on the rate of Si SPE by using molecular dynamics simulation. In the case of non-doped Si, an activation energy of SPE is found to be 2.1±0.5eV, which shows good agreement with the experimental result (2.7eV). It is also found that the energy barrier of crystallization in a/c interface amounts to be about 0.6eV, which corresponds to defect migration process. It indicates other processes such as defect formation also control the SPE process. The SPE rate increases by 2 times for 3 at% As doping and 100 times for 5 at% As doping and an activation energy remains to be constant. The increase in SPE rate would be enhanced by defect formation process in amorphous silicon, which reflects the increase in self-diffusion of silicon atoms caused by active As atoms.
