A theoretical study on the realistic low concentration doping in silicon semiconductors by accelerated quantum chemical molecular dynamics method

We present a theoretical study of the structural and electronic properties of a realistic low concentration (<0.5%) doping model in silicon semiconductor. The density of states was calculated using our newly developed accelerated quantum chemical molecular dynamics method, based on our original tight-binding theory. Using this approach, the band structures of large-size silicon model including n-type and p-type dopants were successfully simulated. The results are in good agreement with the experimental results. Furthermore, we also performed quantum chemical molecular dynamics simulation of the dopants in silicon and observed the change of the dopant levels during the simulation. These results clearly suggest that our original quantum chemical molecular dynamics program is a very effective tool for not only the band structure of a realistically low concentration dopant model but also for the electronic states dynamics of silicon semiconductors.