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Title: Point defects: Their influence on electron trapping, resistivity, and electron mobility-lifetime product in CdTe{sub x}Se{sub 1−x} detectors

In this research, we assessed the abundance of point defects and their influence on the resistivity, the electron mobility-lifetime (μτ{sub e}) product, and the electron trapping time in CdTeSe crystals grown under different conditions using the traveling heater method. We used current-deep level transient spectroscopy to determine the traps' energy, their capture cross-section, and their concentration. Further, we used these data to determine the trapping and de-trapping times for the charge carriers. The data show that detectors with a lower concentration of In-dopant have a higher density of A-centers and Cd double vacancies (V{sub Cd}{sup - -}). The high concentrations of V{sub Cd}{sup - -} and A-centers, along with the deep trap at 0.86 eV and low density of 1.1 eV energy traps, are the major cause of the detectors' low resistivity, and most probably, a major contributor to the low μτ{sub e} product. Our results indicate that the energy levels of point defects in the bandgap, their concentrations, capture cross-sections, and their trapping and de-trapping times play an important role in the detector's performance, especially for devices that rely solely on electron transport.
Authors:
 [1] ;  [2] ; ; ; ; ; ; ;  [1] ;  [3]
  1. Brookhaven National Laboratory, Upton, New York 11973 (United States)
  2. (ECMIT), Normal, Alabama 35762 (United States)
  3. Alabama A&M University (ECMIT), Normal, Alabama 35762 (United States)
Publication Date:
OSTI Identifier:
22494913
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 119; Journal Issue: 2; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; A CENTERS; CADMIUM TELLURIDES; CAPTURE; CHARGE CARRIERS; CROSS SECTIONS; CRYSTALS; DEEP LEVEL TRANSIENT SPECTROSCOPY; DEUTERIUM IONS; ELECTRON MOBILITY; ENERGY LEVELS; LIFETIME; TRAPPING; TRAPS