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Title: Al-doped ZnO contact to CdZnTe for x- and gamma-ray detector applications

Abstract

The poor adhesion of common metals to CdZnTe (CZT)/CdTe surfaces has been a long-standing challenge for radiation detector applications. In this present work, we explored the use of an alternative electrode, viz., Al-doped ZnO (AZO) as a replacement to common metallic contacts. ZnO offers several advantages over the latter, such as having a higher hardness, a close match of the coefficients of thermal expansion for CZT and ZnO, and better adhesion to the surface of CZT due to the contact layer being an oxide. The AZO/CZT contact was investigated via high spatial-resolution X-ray response mapping for a planar detector at the micron level. The durability of the device was investigated by acquiring I–V measurements over an 18-month period, and good long-term stability was observed. We have demonstrated that the AZO/CZT/AZO virtual-Frisch-grid device performs fairly well, with comparable or better characteristics than that for the same detector fabricated with gold contacts.

Authors:
; ; ; ; ; ;  [1]; ;  [2]
  1. Brookhaven National Laboratory, Upton, New York 11973 (United States)
  2. Department of Engineering, Norfolk State University, Norfolk, Virginia 23504 (United States)
Publication Date:
OSTI Identifier:
22590787
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 108; Journal Issue: 24; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CADMIUM TELLURIDES; DOPED MATERIALS; GAMMA DETECTION; GAMMA RADIATION; GOLD; THERMAL EXPANSION; WEAR RESISTANCE; ZINC OXIDES; CDZNTE SEMICONDUCTOR DETECTORS

Citation Formats

Roy, U. N., Camarda, G. S., Cui, Y., Gul, R., Hossain, A., Yang, G., James, R. B., Mundle, R. M., and Pradhan, A. K.. Al-doped ZnO contact to CdZnTe for x- and gamma-ray detector applications. United States: N. p., 2016. Web. doi:10.1063/1.4953883.
Roy, U. N., Camarda, G. S., Cui, Y., Gul, R., Hossain, A., Yang, G., James, R. B., Mundle, R. M., & Pradhan, A. K.. Al-doped ZnO contact to CdZnTe for x- and gamma-ray detector applications. United States. doi:10.1063/1.4953883.
Roy, U. N., Camarda, G. S., Cui, Y., Gul, R., Hossain, A., Yang, G., James, R. B., Mundle, R. M., and Pradhan, A. K.. 2016. "Al-doped ZnO contact to CdZnTe for x- and gamma-ray detector applications". United States. doi:10.1063/1.4953883.
@article{osti_22590787,
title = {Al-doped ZnO contact to CdZnTe for x- and gamma-ray detector applications},
author = {Roy, U. N. and Camarda, G. S. and Cui, Y. and Gul, R. and Hossain, A. and Yang, G. and James, R. B. and Mundle, R. M. and Pradhan, A. K.},
abstractNote = {The poor adhesion of common metals to CdZnTe (CZT)/CdTe surfaces has been a long-standing challenge for radiation detector applications. In this present work, we explored the use of an alternative electrode, viz., Al-doped ZnO (AZO) as a replacement to common metallic contacts. ZnO offers several advantages over the latter, such as having a higher hardness, a close match of the coefficients of thermal expansion for CZT and ZnO, and better adhesion to the surface of CZT due to the contact layer being an oxide. The AZO/CZT contact was investigated via high spatial-resolution X-ray response mapping for a planar detector at the micron level. The durability of the device was investigated by acquiring I–V measurements over an 18-month period, and good long-term stability was observed. We have demonstrated that the AZO/CZT/AZO virtual-Frisch-grid device performs fairly well, with comparable or better characteristics than that for the same detector fabricated with gold contacts.},
doi = {10.1063/1.4953883},
journal = {Applied Physics Letters},
number = 24,
volume = 108,
place = {United States},
year = 2016,
month = 6
}
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