Zincblende-wurtzite phase transformation of ZnSe films by pulsed laser deposition with nitrogen doping

摘要

Nitrogen-doped ZnSe films have been fabricated by pulsed laser deposition. It is found that the incorporation of nitrogen has resulted in a phase transformation from zincblende to wurtzite. By first-principles total energy calculations, two newly observed Raman peaks at 555 cm~(-1) and 602 cm~(-1) are assigned to vibration modes of N substituting Se in wurtzite and zincblende structures, respectively. This preference of wurtzite phase is consistent with previous prediction of the energy difference ΔE_(WZ-ZB) between wurtzite structure and zincblende structure. This work opens a way to achieve stable ZnSe-based polytypism and may help understand the mechanisms of nitrogen doping in wide-bandgap semiconductors.