Impact of Flexible Circuit Bonding and System Integration on Energy Resolution of Cross-Strip CZT Detectors

Abstract

Cadmium Zinc Telluride (CZT) detectors enables high spatial resolution and high detection efficiency and are utilized for many gamma-ray and X-ray spectroscopy applications. In this paper, we describe a stable bonding process and report on the characterization of cross-strip CZT detectors before and after bonding to flexible circuit. The bonding process utilizes gold stud bonding and polymer epoxy technique to bond the flexible circuits to two CZT crystals and form a detector module in an Anode-Cathode-Cathode-Anode (ACCA) configuration. The readout electronics is optimized in terms of shaper setting and steering electrode voltage. The average full width half maximum (FWHM) energy resolution at 662 KeV of 110 CZT crystals tested individually was 3.5% ± 0.59% and 4.75% ± 0.48% prebonded and post-bonded, respectively. No depth correction was performed in this study. The average FWHM energy resolution at 662 KeV of the scaled-up system with 80 CZT crystals was 4.40% ± 0.53%, indicating the scaled-up readout electronics and stacking of the modules does not deteriorate performance. The proper shielding and grounding of the scaled-up system slightly improved the system-wide performance. The FWHM energy resolution at 511 KeV of the scaled-up system was 5.85% ± 0.73%.

Harnessing quantum entanglement for enhanced accuracy in a prototype CZT PET system: a GATE simulation study

“…From GEANT4 v11.0 [2] and on, a QE-model for annihilation gamma rays and adjusted Compton scattering cross sections is included [1]. In this study, we activate QE-GEANT4 in a GATE [3] simulation of a proto-type clinical system: the UCSC 2-Panel PET scanner [4,5]. We investigate the Δϕ distributions of four sets of DCSc coincidence data: (1) spatial blurred and (2) unblurred sets containing only True DCSc coincidences, and (3) spatial blurred and (4) unblurred sets containing only random DCSc coincidences.…”