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 trea tments were used in order to obtain samples with reproducible physical properties. Thin films of GeOx were obtained by thermal oxidation. Su rface analysis was performed using electron spectroscopy for chemical analysis (ESCA). Results show the growth of oxide film (thickness 30 a ngstrom) with a GeO2-like composition. It is also possible to remove t he native germanium oxide with a chemically controlled process. In add ition, two kinds of structures, Al2O3/Ge and Al2O2:GeO2/Ge, were prepa red and characterized electrically. It was found that the germanium ox ide layer can protect the surface during the deposition of alumina usi ng an electron gun evaporation set. In this case, the density of defec ts was greatly reduced.