THE USE OF PULSE PROCESSING TECHNIQUES TO IMPROVE THE PERFORMANCE OF CD1-XZNXTE GAMMA-RAY SPECTROMETERS

Cd1-xZnxTe (CZT) has recently shown great promise for use as a room te mperature gamma-ray detector material. The availability of large volum e (> 1 cm(3)) high resistivity CZT crystals has allowed the demonstrat ion of detectors much larger than can be built with the similar materi al CdTe. However, CZT - like many other room-temperature materials - s uffers from the poor transport properties of holes. The poor hole drif t properties of CZT cause the characteristic ''hole tailing'' in gamma -ray pulse height spectra. We have applied pulse processing methods to reduce the hole tailing effects and improve the energy resolution of CZT detectors. We have used two signal processing methods to reduce ho le tailing in CZT detectors: digital rise-time compensation and dual t ime-constant sampling. We discuss the implementation of these techniqu es, demonstrate results obtained in the laboratory, and compare the pe rformance obtained with other detector systems.