Performance Evaluation of New Large Area 3D CdZnTe Drift Strip Detectors

What do medical imaging and astronomy have in common? Whether it is detecting tumors or observing colliding neutron stars, both fields can benefit from the same sensor technology. When observing radiation in the MeV-band (0.1-100 MeV) from celestial sources, one faces challenges like low flux, limited interaction probability, three energy loss processes, and a high background radiation rate. Present MeV-band observatories suffer from poor sensitivity, and new state-of the-art detector technology will be a key contributor to improve sensitivity of future observatories. The detector group at DTU Space has developed a 3D CdZnTe drift strip detector technology to meet the demands of future high-energy detectors. This advancement also shows potential application for emerging Low Dose Molecular Breast Imaging (LD-MBI) systems for breast cancer diagnosis. In this study, we present the results of the novel large area 3D CZT drift strip detectors (4x4x0.5 cm(3)) developed in a collaboration between DTU Space and Kromek. We find the spatial resolution of these modules to be < 0.6mm in the x- and z-axis, and we measure the spectral resolutions to be < 7% FWHM at 122 keV, < 1.4% FWHM at 661.6 keV, and 1% FWHM above 1460 keV.