ELECTRICAL CHARACTERIZATION OF DEFECTS INTRODUCED IN P-SI1-XGEX DURING ELECTRON-BEAM DEPOSITION OF SC SCHOTTKY-BARRIER DIODES

Scandium (Sc) Schottky barrier diodes were fabricated by electron-beam (EB) deposition on epitaxially grown p-Si1-xGex strained films with x = 0.0-0.2. The EB deposition was performed either with or without shi elding the Si1-xGex samples. The barrier height and the defects introd uced during EB deposition have been investigated as a function of Ge c omposition. Our results showed that the barrier height decreased as th e band gap changed with increasing Ge content. The defect properties w ere studied with deep-level transient spectroscopy. The most prominent defect observed in p-Si was a hole trap H(0.53) at E-v + 0.53 eV. Inc reasing the Ge content led to a decrease in the activation energy of t his defect and this decrease followed the same trend as the band-gap v ariation, suggesting that the main defect detected in p-Si1-xGex is th e same as that observed in p-Si. (C) 1998 American Institute of Physic s.