Oxygen and indium diffusion into SiO2 encapsulated polycrystalline CdSe films

Abstract

The diffusion of oxygen into SiO2 encapsulated polycrystalline CdSe films and the diffusion of indium into polycrystalline CdSe films have been investigated over the temperature range 350 C to 500 C using SIMS. The oxygen profiles in the SiO2 indicated that both isotopic oxygen exchange and the diffusion of molecular oxygen along short circuit paths were occurring with activation energies of 1.1 eV and 0.66 eV, respectively. The activation energies determined for the diffusion of the oxygen and indium in the grains (0.39 eV and 0.10 eV, respectively) were smaller than the values determined for the diffusion in the grain boundaries (0.70 eV and 0.78 eV, respectively), and was attributed to impurities and intrinsic defects accumulating at the grain boundaries.