Design Considerations and Testing of Virtual Frisch-Grid CdZnTe Detector Arrays Using the H3D ASIC

We discussed the design implementation and results from testing 2 x 2-, 3 x 3-, and 2 x 4-arrays of 6 x 6 x 15 mm(3) CdZnTe virtual Frisch-grid detectors. In these measurements we employed a data acquisition system based on the H3D ASIC developed by BNL's Instrumentation Division in collaboration with the University of Michigan for 3D position-sensitive detectors. We used CZT crystals with a range of performance attributes to evaluate practical array configurations and detector-assembling procedures. The detector ratings were assigned based on the pulse-height spectra and correlated with data from X-ray diffraction topography measurements and X-ray response mapping obtained at BNL's National Synchrotron Light Source. The results helped us to better understand the performance limits of these detectors, and to identify future improvements in the array's design and requirements for the new readout ASIC.