SIMS depth profiling of N and In in a ZnO single crystal

Nitrogen (4×1015 ions/cm2) and indium (1×1016 ions/cm2) ions with 200 and 170 keV, respectively, were co-implanted into a ZnO single crystal at room temperature. The ion-implanted sample was annealed at 800 °C under an oxygen atmosphere. The diffusion behaviors of N and In in relation to annealing times were studied by SIMS. Diffusion of N in the crystal was not detected, while In was observed to diffuse deeper into the single crystal during annealing. Due to diffusion of In away from the surface, a second peak of In was created which overlapped with that of N at the limited region of the ZnO crystal. It was confirmed by TEM observation that a band-like layer was formed in the post-annealed sample.