Germanium nitride layers prepared by supersonic rf plasma jet

Rutherford backscattering spectroscopy (RBS) and X-ray photoelectron spectroscopy (XPS) have been used to characterize GexNy films grown on Si substrates. The films were deposited in a plasma chemical reactor by a radio frequency (r.f.)-generated supersonic plasma jet. The Ge nozzle of the r.f. electrode was reactively sputtered in the plasma jet generated in the nitrogen and the germanium nitride films were created in the reactor. The RBS method showed that the ratio Ge:N in the layer was close to the expected stoichiometric ratio 3:4 (for example, 0.73, which is within experimental error) when traces of oxygen were suppressed. The chemical bonding state of Ge-N, as found by XPS analysis, showed that, close to the thin film surface, the Ge:N ratio was also near 3:4. The impurities present, although in small amount, were preferentially bonded into the film.