Pulse shape analysis for electron mobility study in cadmium zinc telluride gamma-ray detectors

A pulse shape analysis technique was implemented to determine electron mobility, /spl mu//sub e/, and electron mobility lifetime product, /spl mu//sub e//spl tau//sub e/ in cadmium zinc telluride detectors (CZT). The digital gamma finder, (DGF-4C), a single width CAMAC module produced by X-ray Instrumentation Associates (XIA), was used to extract pulse height, pulse shape, and signal rise time information. Post data acquisition analysis using the extracted information allowed measuring the /spl mu//sub e/ and /spl mu//sub e//spl tau//sub e/, in selected CZT samples. An almost linear relationship was observed for the signal rise time as a function of the inverse bias. This observed linear relationship was the basis for determination of /spl mu//sub e/ using a simple linear fit. The measured signal amplitude was also used to determine /spl mu//sub e//spl tau//sub e/ using the Hecht formulation. Repeated measurements carried out confirmed the consistency of the method in determining /spl mu//sub e/ and /spl mu//sub e//spl tau//sub e/.