Effects of phosphorus doping by plasma immersion ion implantation on the structural and optical characteristics of Zn0.85Mg0.15O thin films

ZnMgO thin films deposited on Si substrates by RF sputtering were annealed at 800, 900, and 1000 degrees C after phosphorus plasma immersion ion implantation. X-ray diffraction spectra confirmed the presence of and peaks for all the samples. However, in case of the annealed samples, the peak was also observed. Scanning electron microscopy images revealed the variation in surface morphology caused by phosphorus implantation. Implanted and non-implanted samples were compared to examine the effects of phosphorus implantation on the optical properties of ZnMgO. Optical characteristics were investigated by low-temperature (15 K) photoluminescence experiments. Inelastic exciton-exciton scattering and localized, and delocalized excitonic peaks appeared at 3.377, 3.42, and 3.45 eV, respectively, revealing the excitonic effect resulting from phosphorus implantation. This result is important because inelastic exciton-exciton scattering leads to nonlinear emission, which can improve the performance of many optoelectronic devices. (C) 2014 AIP Publishing LLC