Schottky contacts of Gd-Pt and Gd-V alloys on n-Si and p-Si

Alloys of Gd-Pt and Gd-V, both Gd-rich and Pt or V-rich, have been prepared by coevaporation onto n- and p-type Si for Schottky contact formation. Structural and electrical properties of these contacts after various heat treatments have been studied by combining x-ray diffraction, backscattering spectroscopy, and current-voltage measurement. We found that these alloys produced a mixture of silicides on Si; i.e., they formed parallel contacts of GdSi2 and PtSi or GdSi2 and VSi2 to Si. We also found that the sum of apparent Schottky barrier heights of these parallel contacts on n-Si and p-Si is not necessarily equal to the value of the band gap of Si, which we recall is always true for a single phase contact.