ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
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 μm between elements and 100 μm 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 μm FWHM, for a 50 μm 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. © 1995 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1145676
