The electronic structure and optical properties of phosphorus implanted GaN films

Abstract

We have studied optical and electronicc transition properties of GaN layers grown by MOCVD which are implanted by isoelectronic impurities of phosphorus (P). The P-implanted samples were treated by rapid thermal annealing to recover implantation-induced damages. A strong emission band around 430 nm were observed in P-implanted sample due to the recombination of bound exciton to P-hole isoelectronic traps. From the Arrhenius plot, the hole binding energy about 180 meV localized at the P-isoelectronic trap and the exciton localization energy of 28 meV were obtained. According to first-principle total-energy calculations, we suggest that the implantation likely induces N-I or P-related defects. From the PLE, we found that the absorption by band-to-band and shallow donors dominates the yellow luminescence (YL) and the implantation of P has induced localized states that not only increase the YL but also suppress the transition from the free electron-hole pairs to the deep-levels.