PREPARATION AND ESCA ANALYSIS OF THE GERMANIUM SURFACE - ELECTRICAL CHARACTERIZATION OF THE AL2O3/GE AND AL2O3-GEO2/GE STRUCTURES

The preparation of the (100) structure of germanium is a crucial step in the realization of electronic components. Chemical and thermal treatments were used in order to obtain samples with reproducible physical properties. Thin films of GeOx were obtained by thermal oxidation. Surface analysis was performed using electron spectroscopy for chemical analysis (ESCA). Results show the growth of oxide film (thickness 30 angstrom) with a GeO2-like composition. It is also possible to remove the native germanium oxide with a chemically controlled process. In addition, two kinds of structures, Al2O3/Ge and Al2O2:GeO2/Ge, were prepared and characterized electrically. It was found that the germanium oxide layer can protect the surface during the deposition of alumina using an electron gun evaporation set. In this case, the density of defects was greatly reduced.