Metal/Semiconductor Contacts for Schottky and Photoconductive CdZnTe Detector

Electrode materials design of Schottky and photoconductive CZT devices is investigated by I-V electric analyses, barrier heights calculation and spectrum response. The results showed that Al-n/CZT-AuCl3 with better Ohmic coefficient, lower leakage current is propitious to achieve the effective photoconductivity devices. Besides the barrier height of In-p/CZT-Au device was 0.948 eV, with the reverse leakage current only ∼ 8nA at 360 V. Measured by ray source of 241Am, the ratios of signal to noise of Al-n/CZT-AlCl3 device and In-p/CZT-Au device were 1.75 and 2.08, respectively. It indicated that In-p/CZT-Au could minish noise affection effectively.