Copper germanide Schottky barrier contacts to silicon

Copper germanide Schottky barrier contacts have been fabricated on both n- and p-type silicon via sequential evaporation of thin layers of germanium and copper followed by an annealing schedule in the temperature range up to 673 K. Silicon is found to outdiffuse into the contact as observed by secondary-ion-mass spectrometry as the annealing temperature is increased. The barrier heights of the contacts were examined via capacitance-voltage and current-voltage techniques in the temperature range of 80-300 K while electrically active defects were probed by deep level transient spectroscopy. The Schottky barrier height for copper germanide is found to be independent of the germanium concentration and similar to that reported for copper silicide. (C) 1996 American Institute of Physics.