MBE grown CdTe photoconductor array detector for x-ray measurements

Journal Article · Tue Jan 31 23:00:00 EST 1995 · Review of Scientific Instruments; (United States)

DOI:https://doi.org/10.1063/1.1145676· OSTI ID:6864864

Yoo, S S ^[1]; Rodricks, B ^[2]; Sivananthan, S; Faurie, J P ^[3]; Montano, P A ^[1]

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1. Microphysics Laboratory, Department of Physics, University of Illinois at Chicago, Chicago, Illinois 60607 (United States) Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
2. Experimental Facility Division, Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States)
3. Microphysics Laboratory, Department of Physics, University of Illinois at Chicago, Chicago, Illinois 60607 (United States)

A photoconductor array was made using molecular-beam epitaxy (MBE) grown CdTe. CdTe has been found to be an excellent material for high-energy photon detection. The objective is to develop an array detector with high efficiency and fast response toward x rays. There is considerable interest in the development of new x-ray detectors for use in the new synchrotron-radiation sources. Photoconductor arrays with gaps ranging from 5 to 50 [mu]m between elements and 100 [mu]m pitch size have been fabricated. The temporal response of the detectors was measured using 100 fs Ti:sapphire laser pulses. The temporal response of the photoconductor arrays is as fast as 21 ps rise time and 38 ps full width half maximum (FWHM). Spatial and energy responses were obtained using x rays from rotating anode (ANL) and synchrotron-radiation sources (NSLS, beam line X-18 B). The spatial resolution of the photoconductor obtained was 75 [mu]m FWHM, for a 50 [mu]m beam size. The best results were obtained for those arrays with the best crystal qualities. Linear response up to an energy of 15 keV was observed. Also observed was that a substantial number of x-ray photons were effectively absorbed within the MBE CdTe layer. The array detector did not show any evidence of radiation damage after x-ray exposures of several days. When the detector is cooled to 230 K the signal-to-noise ratio is improved by more than an order of magnitude. These results demonstrate that MBE grown CdTe is a suitable choice to meet the detector requirements for synchrotron-radiation applications.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6864864
• Journal Information: Review of Scientific Instruments; (United States), Journal Name: Review of Scientific Instruments; (United States) Vol. 66:2; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

440101* -- Radiation Instrumentation-- General Detectors or Monitors & Radiometric Instruments
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
CADMIUM COMPOUNDS
CADMIUM TELLURIDES
CHALCOGENIDES
DETECTION
EPITAXY
FEASIBILITY STUDIES
MEASURING INSTRUMENTS
MOLECULAR BEAM EPITAXY
PHOTOCONDUCTORS
POSITION SENSITIVE DETECTORS
RADIATION DETECTION
RADIATION DETECTORS
RESOLUTION
SIGNAL-TO-NOISE RATIO
SPATIAL RESOLUTION
TELLURIDES
TELLURIUM COMPOUNDS
TIME RESOLUTION
TIMING PROPERTIES
X-RAY DETECTION