The ratio Oxygen/zZinc effect on photoluminescence emission line at 3.31 eV in ZnO nanowires

摘要

We have studied the photoluminescence emission line at 3.31 eV in ZnO nanowires. In undoped ZnO, this band strongly depends on high oxygen concentration and could originate from recombination of bound-exciton complex related to structural defects. Conversely, in doped ones, the photoluminescence emission appears notably at a low Ⅵ/Ⅱ ratio and with the emergence of donor-acceptor pair emission due to the presence of α-N_o nitrogen complex, which acts as a shallow acceptor in ZnO. We found that this band corresponds to 3LO, the third phonon replica of resonant Raman scattering. Furthermore, a remarkable variation is detected in a number of resonant Raman scattering multiphonons.