Effect of Interface Trap States on Optical Barrier Height of NiSi/Si Infrared Detector

In this paper, influence of interface trap states on barrier height of NiSi/Si Schottky diode is presented. The proposed study is important in view of its application potential as an infrared detector. This involves preparation of silicide by depositing 10 nm thick nickel on n-Si, followed by rapid thermal annealing at 500 0C in argon ambience. The thickness of the silicide was measured by cross-sectional HRTEM and found to be 24 nm. The zero bias barrier heights were measured by current-voltage and optical techniques, and were found to be 0.62 eV and 0.54 eV respectively. This discrepancy in barrier height is attributed to the presence of acceptor like interface trap state which was identified by DLTS technique.