DocumentCode :
323254
Title :
CdZnTe semiconductor parallel Frisch grid radiation detectors
Author :
McGregor, D.S. ; He, Z. ; Seifert, H.A. ; Rojeski, R.A. ; Wehe, D.K.
Author_Institution :
Dept. of Nucl. Eng. & Radiol. Sci., Michigan Univ., MI, USA
fYear :
1997
fDate :
9-15 Nov 1997
Firstpage :
629
Abstract :
Position-dependent free charge carrier losses during transport can prevent efficient charge carrier extraction from semiconductor detectors and severely reduce energy resolution. Hole trapping losses in CdZnTe radiation detectors are far worse than electron trapping losses and resolution degradation in CdZnTe detectors results primarily from severe hole trapping during transport. Coplanar radiation detectors improve energy resolution by sensing the induced charge primarily from the motion of electrons. Demonstrated is an alternative approach to single free charge carrier sensing, in which a parallel Frisch grid is fabricated on either side of a parallelepiped block. The detectors are three terminal devices, but require only one preamplifier for the output signal. The prototype devices demonstrate a considerable increase in energy resolution when operated in the true Frisch grid mode rather than the planar mode, with a demonstrated room temperature energy resolution of 5.91% at FWHM for a 10 mm×2 mm×10 mm device. Presently, high surface leakage currents prevent large voltages from being applied devices, which ultimately reduces their maximum achievable energy resolution. Further improvements are expected with the realization of reduced surface leakage currents
Keywords :
II-VI semiconductors; cadmium compounds; hole traps; leakage currents; semiconductor counters; zinc compounds; CdZnTe; CdZnTe radiation detectors; CdZnTe semiconductor parallel Frisch grid radiation detectors; coplanar radiation detectors; efficient charge carrier extraction; electron trapping losses; energy resolution; high surface leakage currents; hole trapping losses; planar mode; position-dependent free charge carrier losses; preamplifier; resolution degradation; room temperature energy resolution; semiconductor detectors; three terminal devices; true Frisch grid mode; Charge carrier processes; Charge carriers; Degradation; Electron traps; Energy resolution; Leakage current; Preamplifiers; Prototypes; Radiation detectors; Semiconductor radiation detectors;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Nuclear Science Symposium, 1997. IEEE
Conference_Location :
Albuquerque, NM
ISSN :
1082-3654
Print_ISBN :
0-7803-4258-5
Type :
conf
DOI :
10.1109/NSSMIC.1997.672660
Filename :
672660
Link To Document :
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