A study was made of Sc Schottky barrier diodes which had been prepared by electron-beam deposition onto epitaxially grown p-type Si1-xGex strained films, where x ranged from 0 to 0.2. The defects which were introduced during electron-beam deposition were investigated as a function of the Ge composition. The results showed that the barrier height decreased as the band-gap varied with increasing Ge content. The defect properties were studied by using deep-level transient spectroscopy. The most prominent defect that was observed in p-Si was a hole trap at Ev + 0.53eV. Increasing the Ge content led to a decrease in the activation energy of this defect, and this decrease followed the same trend as the band-gap variation; thus suggesting that the main defect which was detected in p-SiGe was the same as that observed in p-Si.

M.Mamor, F.D.Auret, S.A.Goodman, G.Myburg: Applied Physics Letters, 1998, 72[9], 1069-71