Oxygen and indium diffusion into SiO2 encapsulated polycrystalline CdSe films

The diffusion of oxygen into SiO2 encapsulated polycrystalline CdSe films a nd the diffusion of indium into polycrystalline CdSe films have been invest igated over the temperature range 350 degreesC to 500 degreesC using SIMS. The oxygen profiles in the SiO2 indicated that both isotopic oxygen exchang e and the diffusion of molecular oxygen along short circuit paths were occu rring with activation energies of 1.1 eV and 0.66 eV, respectively. The act ivation energies determined for the diffusion of the oxygen and indium in t he 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 accum ulating at the grain boundaries.