skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Study of Chemical Etching and Chemo-Mechanical Polishing on CdZnTe Nuclear Detectors

Abstract

Cadmium zinc telluride (CdZnTe) semiconductor has applications in the detection of Xrays and gamma-rays at room temperature without having to use a cooling system. Chemical etching and chemo-mechanical polishing are processes used to smoothen CdZnTe wafer during detector device fabrication. These processes reduce surface damages left after polishing the wafers. In this paper, we compare the effects of etching and chemo-mechanical polishing on CdZnTe nuclear detectors, using a solution of hydrogen bromide in hydrogen peroxide and ethylene glycol mixture. X-ray photoelectron spectroscopy (XPS) was used to monitor TeO 2 on the wafer surfaces. Current-voltage and detector-response measurements were made to study the electrical properties and energy resolution. XPS results showed that the chemical etching process resulted in the formation of more TeO 2 on the detector surfaces compared to chemo-mechanical polishing. The electrical resistivity of the detector is of the order of 10 10 Ω-cm. The chemo-mechanical polishing process increased the leakage current more that chemical etching. For freshly treated surfaces, the etching process is more detrimental to the energy resolution more than chemo-mechanically polishing. The energy resolutions of the CdZnTe wafers are expected to improve as the surfaces stabilize and result in reduced surface currents.

Authors:
 [1];  [2];  [3];  [4];  [3];  [2];  [5]
  1. Alabama A&M Univ., Huntsville, AL (United States)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States)
  3. Alabama A&M Univ., Huntsville, AL (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
  4. Federal Univ. of Petroleum Resources, Delta State (Nigeria)
  5. Savannah River National Lab, Aiken, SC (United States)
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), Aiken, SC (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA), Office of Nonproliferation and Verification Research and Development (NA-22); USDOE Office of Environmental Management (EM); USDOE National Nuclear Security Administration (NNSA), Office of Defense Nuclear Nonproliferation (NA-20)
OSTI Identifier:
1546037
Alternate Identifier(s):
OSTI ID: 1591776
Report Number(s):
BNL-211890-2019-JAAM; SRNL-STI-2019-00466
Journal ID: ISSN 2327-6045
Grant/Contract Number:  
SC0012704; AC09-08SR22470; NRC-27-10-514
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Materials Science and Chemical Engineering
Additional Journal Information:
Journal Volume: 07; Journal Issue: 08; Journal ID: ISSN 2327-6045
Publisher:
Scientific Research Publishing, Inc.
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CdZnTe; Chemical Etching; Chemo-mechanical Polishing; Gamma Rays; Nuclear Detectors; X-ray Photoelectron Spectroscopy

Citation Formats

Adams, Aaron L., Roy, Utpal N., Egarievwe, Stephen U., Agbalagba, Ezekiel O., Gul, Rubi, Hossain, Anwar, and James, Ralph B. Study of Chemical Etching and Chemo-Mechanical Polishing on CdZnTe Nuclear Detectors. United States: N. p., 2019. Web. doi:10.4236/msce.2019.78005.
Adams, Aaron L., Roy, Utpal N., Egarievwe, Stephen U., Agbalagba, Ezekiel O., Gul, Rubi, Hossain, Anwar, & James, Ralph B. Study of Chemical Etching and Chemo-Mechanical Polishing on CdZnTe Nuclear Detectors. United States. doi:10.4236/msce.2019.78005.
Adams, Aaron L., Roy, Utpal N., Egarievwe, Stephen U., Agbalagba, Ezekiel O., Gul, Rubi, Hossain, Anwar, and James, Ralph B. Tue . "Study of Chemical Etching and Chemo-Mechanical Polishing on CdZnTe Nuclear Detectors". United States. doi:10.4236/msce.2019.78005. https://www.osti.gov/servlets/purl/1546037.
@article{osti_1546037,
title = {Study of Chemical Etching and Chemo-Mechanical Polishing on CdZnTe Nuclear Detectors},
author = {Adams, Aaron L. and Roy, Utpal N. and Egarievwe, Stephen U. and Agbalagba, Ezekiel O. and Gul, Rubi and Hossain, Anwar and James, Ralph B.},
abstractNote = {Cadmium zinc telluride (CdZnTe) semiconductor has applications in the detection of Xrays and gamma-rays at room temperature without having to use a cooling system. Chemical etching and chemo-mechanical polishing are processes used to smoothen CdZnTe wafer during detector device fabrication. These processes reduce surface damages left after polishing the wafers. In this paper, we compare the effects of etching and chemo-mechanical polishing on CdZnTe nuclear detectors, using a solution of hydrogen bromide in hydrogen peroxide and ethylene glycol mixture. X-ray photoelectron spectroscopy (XPS) was used to monitor TeO2 on the wafer surfaces. Current-voltage and detector-response measurements were made to study the electrical properties and energy resolution. XPS results showed that the chemical etching process resulted in the formation of more TeO2 on the detector surfaces compared to chemo-mechanical polishing. The electrical resistivity of the detector is of the order of 1010 Ω-cm. The chemo-mechanical polishing process increased the leakage current more that chemical etching. For freshly treated surfaces, the etching process is more detrimental to the energy resolution more than chemo-mechanically polishing. The energy resolutions of the CdZnTe wafers are expected to improve as the surfaces stabilize and result in reduced surface currents.},
doi = {10.4236/msce.2019.78005},
journal = {Journal of Materials Science and Chemical Engineering},
issn = {2327-6045},
number = 08,
volume = 07,
place = {United States},
year = {2019},
month = {8}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Figures / Tables:

Figure 1 Figure 1: XPS spectra showing Te and TeO2 peaks: (a) chemically etched after mechanical polishing (from the same data set repoted in [20]), and (b) chemomechanically polished after mechanical polishing.

Save / Share:
Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.