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Title: An analysis of point defects induced by In, Al, Ni, and Sn dopants in Bridgman-grown CdZnTe detectors and their influence on trapping of charge carriers

Abstract

In this paper, we studied point defects induced in Bridgman-grown CdZnTe detectors doped with Indium (In), Aluminium (Al), Nickel (Ni), and Tin (Sn). Point defects associated with different dopants were observed, and these defects were analyzed in detail for their contributions to electron/hole (e/h) trapping. We also explored the correlations between the nature and abundance of the point defects with their influence on the resistivity, electron mobility-lifetime (μτ e) product, and electron trapping time. We used current-deep level transient spectroscopy to determine the energy, capture cross-section, and concentration of each trap. Furthermore, we used the data to determine the trapping and de-trapping times for the charge carriers. In In-doped CdZnTe detectors, uncompensated Cd vacancies (V Cd -) were identified as a dominant trap. The V Cd - were almost compensated in detectors doped with Al, Ni, and Sn, in addition to co-doping with In. Dominant traps related to the dopant were found at E v + 0.36 eV and E v + 1.1 eV, E c + 76 meV and E v + 0.61 eV, E v + 36 meV and E v + 0.86 eV, E v + 0.52 eV and E c + 0.83 eV in CZT:In, CZT:Inmore » + Al, CZT:In + Ni, and CZT:In + Sn, respectively. Results indicate that the addition of other dopants with In affects the type, nature, concentration (N t), and capture cross-section (σ) and hence trapping (t t) and de-trapping (t dt) times. Finally, the dopant-induced traps, their corresponding concentrations, and charge capture cross-section play an important role in the performance of radiation detectors, especially for devices that rely solely on electron transport.« less

Authors:
ORCiD logo [1]; ORCiD logo [1];  [2]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States); Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
Publication Date:
Research Org.:
Brookhaven National Lab. (BNL), Upton, NY (United States); Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
Sponsoring Org.:
USDOE; BNL Laboratory Directed Research and Development (LDRD) Program
OSTI Identifier:
1408811
Alternate Identifier(s):
OSTI ID: 1349378
Report Number(s):
SRNL-STI-2017-00209
Journal ID: ISSN 0021-8979
Grant/Contract Number:  
AC09-08SR22470
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Applied Physics
Additional Journal Information:
Journal Volume: 121; Journal Issue: 11; Journal ID: ISSN 0021-8979
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; doping; point defects; electrical resistivity; charge carriers; nickel

Citation Formats

Gul, R., Roy, U. N., and James, R. B. An analysis of point defects induced by In, Al, Ni, and Sn dopants in Bridgman-grown CdZnTe detectors and their influence on trapping of charge carriers. United States: N. p., 2017. Web. doi:10.1063/1.4978377.
Gul, R., Roy, U. N., & James, R. B. An analysis of point defects induced by In, Al, Ni, and Sn dopants in Bridgman-grown CdZnTe detectors and their influence on trapping of charge carriers. United States. https://doi.org/10.1063/1.4978377
Gul, R., Roy, U. N., and James, R. B. Wed . "An analysis of point defects induced by In, Al, Ni, and Sn dopants in Bridgman-grown CdZnTe detectors and their influence on trapping of charge carriers". United States. https://doi.org/10.1063/1.4978377. https://www.osti.gov/servlets/purl/1408811.
@article{osti_1408811,
title = {An analysis of point defects induced by In, Al, Ni, and Sn dopants in Bridgman-grown CdZnTe detectors and their influence on trapping of charge carriers},
author = {Gul, R. and Roy, U. N. and James, R. B.},
abstractNote = {In this paper, we studied point defects induced in Bridgman-grown CdZnTe detectors doped with Indium (In), Aluminium (Al), Nickel (Ni), and Tin (Sn). Point defects associated with different dopants were observed, and these defects were analyzed in detail for their contributions to electron/hole (e/h) trapping. We also explored the correlations between the nature and abundance of the point defects with their influence on the resistivity, electron mobility-lifetime (μτe) product, and electron trapping time. We used current-deep level transient spectroscopy to determine the energy, capture cross-section, and concentration of each trap. Furthermore, we used the data to determine the trapping and de-trapping times for the charge carriers. In In-doped CdZnTe detectors, uncompensated Cd vacancies (VCd-) were identified as a dominant trap. The VCd- were almost compensated in detectors doped with Al, Ni, and Sn, in addition to co-doping with In. Dominant traps related to the dopant were found at Ev + 0.36 eV and Ev + 1.1 eV, Ec + 76 meV and Ev + 0.61 eV, Ev + 36 meV and Ev + 0.86 eV, Ev + 0.52 eV and Ec + 0.83 eV in CZT:In, CZT:In + Al, CZT:In + Ni, and CZT:In + Sn, respectively. Results indicate that the addition of other dopants with In affects the type, nature, concentration (Nt), and capture cross-section (σ) and hence trapping (tt) and de-trapping (tdt) times. Finally, the dopant-induced traps, their corresponding concentrations, and charge capture cross-section play an important role in the performance of radiation detectors, especially for devices that rely solely on electron transport.},
doi = {10.1063/1.4978377},
url = {https://www.osti.gov/biblio/1408811}, journal = {Journal of Applied Physics},
issn = {0021-8979},
number = 11,
volume = 121,
place = {United States},
year = {2017},
month = {3}
}

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Works referenced in this record:

Defect levels and thermomigration of Te precipitates in CdZnTe:Pb
journal, March 2010


Systematic modelling and comparisons of capacitance and current-based microscopic defect analysis techniques for measurements of high-resistivity silicon detectors after irradiation
journal, February 1998


Study of impurity segregation, crystallinity, and detector performance of melt-grown cadmium zinc telluride crystals
journal, April 2002


CdZnTe and CdTe materials for X-ray and gamma ray radiation detector applications
journal, March 2004


Point Defects in Pb-, Bi-, and In-Doped CdZnTe Detectors: Deep-Level Transient Spectroscopy (DLTS) Measurements
journal, November 2011


Investigation on defect levels in CdZnTe : Al using thermally stimulated current spectroscopy
journal, August 2010


Characterization of deep levels in CdTe by photo-EPR and related techniques
journal, April 1990


Investigation of the electronic properties of cadmium zinc telluride surfaces using pulsed laser microwave cavity perturbation
conference, December 2001


Cadmium zinc telluride and its use as a nuclear radiation detector material
journal, April 2001


High compositional homogeneity of CdTe x Se 1−x crystals grown by the Bridgman method
journal, February 2015


Role of zinc in CdZnTe radiation detectors
journal, October 2004


Dependence of the Sn 0/2+ charge state on the Fermi level in semi-insulating CdTe
journal, November 2007


Development of Cadmium Magnesium Telluride (Cd1−xMgxTe) for room temperature X- and gamma-ray detectors
journal, September 2013


Point Defects in CdZnTe Crystals Grown by Different Techniques
journal, February 2011


Identification of the isolated deep Ni acceptor in CdTe and ZnTe: comparison with isomorphous systems
journal, December 1984


Study of Different Cool Down Schemes During the Crystal Growth of Detector Grade CdZnTe
journal, October 2011


Comparative study of vertical gradient freeze grown CdTe with variable Sn concentration
journal, April 2006


    Works referencing / citing this record:

    Macroscopic effects and microscopic origins of gamma-ray irradiation on In-doped CdZnTe crystal
    journal, October 2018