| Abstract: | The chemical processes which take place during annealing were studied in both model substances and thin films deposited onto GaAs wafers by thermal analysis, X-ray powder diffraction, IR spectroscopy, XPS and TEM. It was found that at 600°C only about 45% of the film was changed to SiO2 glass. At 700 °C begins the formation of zinc silicates. In this form the zinc seems to be scarcely able to diffuse into GaAs. Obviously, the exothermic DTA effect at 800 °C arises from this zinc silicate formation connected with a recrystallization of the amorphous film. |
