1-D POSITION-SENSITIVE SINGLE CARRIER SEMICONDUCTOR

A single polarity charge sensing method has been studied using coplana r electrodes on 5 mm cubes of CdZnTe gamma-ray detectors. This method can ameliorate the hole trapping problem of room-temperature semicondu ctor detectors. Our experimental results confirm that the energy resol ution is dramatically improved compared with that obtained using the c onventional readout method, but is still about an order of magnitude w orse than the theoretical limit. A method to obtain the gamma-ray inte raction depth between the cathode and the anode is presented here. Thi s technique could be used to correct for the electron trapping as a fu nction of distance from the coplanar electrodes. Experimental results showed that a position resolution of about 0.9 mm FWHM at 122 keV can be obtained. These results will be of interest in the design of higher performance room-temperature semiconductor gamma-ray detectors.