Effect of the inversion layer on the electrical characterization of Pt germanide/n-Ge(001) Schottky contacts

Schottky contacts of Pt germanide films formed on n-Ge(001) through solid-state reaction between Pt and Ge(001) via rapid thermal annealing were investigated. Almost identical effective barrier heights of ∼0.619–0.626eV were obtained for PtGe∕n-Ge(001), Pt2Ge3∕n−Ge(001), and PtGe2∕n-Ge(001) Schottky contacts from current-voltage measurements. From the effective barrier height values, actual barrier heights of ∼0.653–0.663eV were determined by taking into account the image force induced barrier lowering in the presence of strong inversion layers at the interfaces. The actual barrier height values obtained were further validated by the good agreement between experimental and simulation results for capacitance-voltage characterization.