We report progress in the study of a thick CZT strip detector module designed to perform gamma-ray spectroscopy and 3-D imaging. We report preliminary performance measurements of 7.5 mm thick single-sided charge-sharing strip detector prototype devices. This design features both row and column contacts on the anode surface. This electron-only approach addresses problems associated with poor hole transport in CZT that limit the thickness and energy range of double-sided strip detectors. This work includes laboratory and simulation studies aimed at developing compact, efficient, detector modules for 0.05 to 1 MeV gamma measurements while minimizing the number and complexity of the electronic readout channels. This is particularly important in space-based coded aperture and Compton telescope instruments that require large area, large volume detector arrays. Such arrays will be required for the NASA Black Hole Finder Probe (BHFP)and Advanced Compton Telescope (ACT). This new design requires an anode pattern with contacts whose dimensions and spacing are roughly the size of the ionization charge cloud. The first prototype devices have 125 μm anode contacts on 225 μm pitch. Our results demonstrate the principle of operation but suggest that even finer anode contact feature sizes will be necessary to achieve the desired performance.
Digital Object Identifier (DOI)
Burcin Donmez ; John R. Macri ; Mark L. McConnell ; James M. Ryan ; Mark Widholm ; Tomohiko Narita and Louis-Andre Hamel "Further studies of single-sided charge-sharing CZT strip detectors", Proc. SPIE 5922, Hard X-Ray and Gamma-Ray Detector Physics VII, 59220H (September 16, 2005); doi:10.1117/12.617297; http://dx.doi.org/10.1117/12.617297
© (2005) COPYRIGHT SPIE--The International Society for Optical Engineering.