Schottky Contacts on n-InP with High Barrier Heights and Reduced Fermi-Level Pinning by a Novel In Situ Electrochemical Process

Schottky contacts on n-InP were fabricated by a novel in situ electrochemical process. The characteristics of the Schottky contacts were investigated using atomic force microscopy (AFM), X-ray photoemission spectroscopy (XPS), current-voltage ( I - V ) and capacitance-voltage ( C - V ) techniques. The results of AFM and XPS measurements indicate that the novel in situ electrochemical process produces smooth and oxide-free interfaces. The Schottky contacts show nearly ideal thermionic emission characteristics. The novel electrochemical process was found to reduce Fermi-level pinning at the Schottky contact interfaces. The Schottky barrier height was found to change over a wide range from 0.35 eV to 0.86 eV, depending on the work function of the contact metals. The Pt/InP contact gave the highest barrier height of 0.86 eV.