CZT device with improved sensitivity for medical imaging and homeland security applications

Abstract

A special CdZnTe (CZT) device on THM grown crystal has been developed. The device has different work function metals on opposite electrodes yet operates at room temperature like a conventional back-to-back symmetric MSM detector and not a one directional Schottky diode device. Aiming at creating a big breakthrough in CZT imaging device technology, the special CZT device presented in this study is capable of increasing the photopeak count by up to 50% compared to conventional CZT imaging device while maintaining good room temperature energy resolution by not significantly trading off detector leakage current. Pixel pad size and interpixel gap on a 20x20x5 mm3, 8x8 pixel pattern that result in optimum detector efficiency and interpixel resistance are presented. Sensitivity improvement impact on other device configuration will also be discussed. The design is highly practical, reliable and suitable for mass production.