Deep level transient spectroscopy study of nickel-germanide Schottky barriers on n-type germanium

摘要

Nickel-germanide Schottky barriers have been made on n-type germanium and evaluated by deep level transient spectroscopy in order to detect possible metal indiffusion during the 30 s rapid thermal annealing (RTA) employed for the germanidation. It is shown that while no electron traps have been found for the 300 and 350℃ RTA step, the double acceptor level at E_C-0.3 eV of substitutional nickel was observed for the 400 and 450℃ samples. The corresponding concentration profile increases exponentially towards the surface from which an effective diffusion coefficient of ～5 X 10~(-10) cm~2/s at 450℃ has been derived.