Coplanar grid patterns and their effect on energy resolution of CdZnTe detectors

This paper describes diagnostic techniques using depth and radial position-sensing methods that have been applied to identify and remove the non-symmetric effect of coplanar grid electrodes. Our experimental results show that the non-symmetric effect can degrade significantly the energy resolution of single polarity charge sensing CdZnTe detectors and can be minimized by balancing the weighting potentials of coplanar anodes. The coplanar electrode design has been modified based on the knowledge gained from this study and improvements in detector performance have been achieved.