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Title: Non-monotonic temperature dependence of radiation defect dynamics in silicon carbide

Abstract

Understanding response of solids to particle irradiation remains a major materials physics challenge. This applies even to SiC, which is a prototypical nuclear ceramic and wide-band-gap semiconductor material. The lack of predictability is largely related to the complex, dynamic nature of radiation defect formation. Here, we use a novel pulsed-ion-beam method to study dynamic annealing in 4H-SiC ion-bombarded in the temperature range of 25–250 °C. We find that, while the defect recombination efficiency shows an expected monotonic increase with increasing temperature, the defect lifetime exhibits a non-monotonic temperature dependence with a maximum at ~100 °C. This finding indicates a change in the dominant defect interaction mechanism at ~100 °C. As a result, the understanding of radiation defect dynamics may suggest new paths to designing radiation-resistant materials.

Authors:
 [1];  [2];  [3];  [1]
  1. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
  2. Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Texas A&M Univ., College Station, TX (United States)
  3. Texas A&M Univ., College Station, TX (United States)
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1297652
Report Number(s):
LLNL-JRNL-677429
Journal ID: ISSN 2045-2322; TRN: US1601834
Grant/Contract Number:
AC52-07NA27344
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 6; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Bayu Aji, L. B., Wallace, J. B., Shao, L., and Kucheyev, S. O.. Non-monotonic temperature dependence of radiation defect dynamics in silicon carbide. United States: N. p., 2016. Web. doi:10.1038/srep30931.
Bayu Aji, L. B., Wallace, J. B., Shao, L., & Kucheyev, S. O.. Non-monotonic temperature dependence of radiation defect dynamics in silicon carbide. United States. doi:10.1038/srep30931.
Bayu Aji, L. B., Wallace, J. B., Shao, L., and Kucheyev, S. O.. 2016. "Non-monotonic temperature dependence of radiation defect dynamics in silicon carbide". United States. doi:10.1038/srep30931. https://www.osti.gov/servlets/purl/1297652.
@article{osti_1297652,
title = {Non-monotonic temperature dependence of radiation defect dynamics in silicon carbide},
author = {Bayu Aji, L. B. and Wallace, J. B. and Shao, L. and Kucheyev, S. O.},
abstractNote = {Understanding response of solids to particle irradiation remains a major materials physics challenge. This applies even to SiC, which is a prototypical nuclear ceramic and wide-band-gap semiconductor material. The lack of predictability is largely related to the complex, dynamic nature of radiation defect formation. Here, we use a novel pulsed-ion-beam method to study dynamic annealing in 4H-SiC ion-bombarded in the temperature range of 25–250 °C. We find that, while the defect recombination efficiency shows an expected monotonic increase with increasing temperature, the defect lifetime exhibits a non-monotonic temperature dependence with a maximum at ~100 °C. This finding indicates a change in the dominant defect interaction mechanism at ~100 °C. As a result, the understanding of radiation defect dynamics may suggest new paths to designing radiation-resistant materials.},
doi = {10.1038/srep30931},
journal = {Scientific Reports},
number = ,
volume = 6,
place = {United States},
year = 2016,
month = 8
}

Journal Article:
Free Publicly Available Full Text
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Citation Metrics:
Cited by: 2works
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