Study of metal-related deep-level defects in germanide Schottky barriers on n-type germanium

摘要

Deep levels have been studied in n-type germanium subjected to Co, Fe, Cu, Cr, and Pt germanidation in the temperature range between 300 and 700 ℃ by deep-level transient spectroscopy (DLTS). It is shown that most DLTS peaks can be assigned to acceptor levels of substitutional metal atoms. However, while in the case of Co, Fe, and Cu we have clear evidence of the indiffusion of the respective metals during the germanidation step, contamination with fast-diffusing Cu dominates the spectra for the Cr and Pt samples. At the same time, the occurrence of minority carrier traps during a bias pulse in forward operation is demonstrated and the interpretation of the corresponding peaks is discussed.