Development of IMARAD CZT detectors with PIN contacts

Abstract

We present initial result from our evaluation of a PIN contacted pixelated detector using cadmium zinc telluride substrate produced by IMARAD Imaging Systems. The Horizontal Bridgman (HB) grown crystals from IMARAD have been shown to produce high resolution photopeaks but they are also seen to have large dark current. We seek to test whether the use of PIN contacts could reduce the dark current and thus improve the spectral response especially in the 10-100 keV energy range. We have fabricated PIN and MIN detector with a 4 X 4 array of pixels on 10 X 10 mm substrates. Measurements of the detectors' dark current, spectral response, and internal electric field are presented and compared to IMARAD's ohmic contact detector and PIN detectors made of High Pressure Bridgman material.