In:
Journal of Synchrotron Radiation, International Union of Crystallography (IUCr), Vol. 24, No. 2 ( 2017-03-01), p. 429-438
Abstract:
Recently, CdZnTe (CZT) detectors have been widely proposed and developed for room-temperature X-ray spectroscopy even at high fluxes, and great efforts have been made on both the device and the crystal growth technologies. In this work, the performance of new travelling-heater-method (THM)-grown CZT detectors, recently developed at IMEM-CNR Parma, Italy, is presented. Thick planar detectors (3 mm thick) with gold electroless contacts were realised, with a planar cathode covering the detector surface (4.1 mm × 4.1 mm) and a central anode (2 mm × 2 mm) surrounded by a guard-ring electrode. The detectors, characterized by low leakage currents at room temperature (4.7 nA cm −2 at 1000 V cm −1 ), allow good room-temperature operation even at high bias voltages ( 〉 7000 V cm −1 ). At low rates (200 counts s −1 ), the detectors exhibit an energy resolution around 4% FWHM at 59.5 keV ( 241 Am source) up to 2200 V, by using commercial front-end electronics (A250F/NF charge-sensitive preamplifier, Amptek, USA; nominal equivalent noise charge of 100 electrons RMS). At high rates (1 Mcounts s −1 ), the detectors, coupled to a custom-designed digital pulse processing electronics developed at DiFC of University of Palermo (Italy), show low spectroscopic degradations: energy resolution values of 8% and 9.7% FWHM at 59.5 keV ( 241 Am source) were measured, with throughputs of 0.4% and 60% at 1 Mcounts s −1 , respectively. An energy resolution of 7.7% FWHM at 122.1 keV ( 57 Co source) with a throughput of 50% was obtained at 550 kcounts s −1 (energy resolution of 3.2% at low rate). These activities are in the framework of an Italian research project on the development of energy-resolved photon-counting systems for high-flux energy-resolved X-ray imaging.
Type of Medium:
Online Resource
ISSN:
1600-5775
DOI:
10.1107/S1600577517000194
Language:
Unknown
Publisher:
International Union of Crystallography (IUCr)
Publication Date:
2017
detail.hit.zdb_id:
2021413-3
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