Disordering of ZnSe/ZnS strained-layer superlattices by Si ion implantation

Disordering of ZnSe/ZnS strained-layer superlattices(SLSs) induced by Si ion implantation and subsequent low-temperature thermal annealing was confirmed. Si ions were implanted (100 keV, 1×1016 ions/cm2 ) into SLSs (140 Å ZnSe-140 Å ZnS, ten periods). By secondary-ion mass spectrometry analyses, periodic profiles of Se and S were clearly observed just after the ion implantation; however, they disappeared after subsequent thermal annealing (450 °C, 3 h). Photoluminescence measurements showed the peak of ZnSx Se1−x alloyed crystal after thermal annealing. The disordering is mainly induced by the diffusion of defects generated by the ion implantation at the early stage of low-temperature thermal annealing. This low temperature and planar process will be very useful to the fabrication of II-VI compound semiconductor optical and electrical devices.