Effect of extended defects on photoluminescence of gallium oxide and aluminum gallium oxide epitaxial films

Jacqueline Cooke; Praneeth Ranga; Jani Jesenovec; John S. McCloy; Sriram Krishnamoorthy; Michael A. Scarpulla; Berardi Sensale-Rodriguez

doi:10.1038/s41598-022-07242-z

Scientific Reports (Feb 2022)

Effect of extended defects on photoluminescence of gallium oxide and aluminum gallium oxide epitaxial films

Jacqueline Cooke,
Praneeth Ranga,
Jani Jesenovec,
John S. McCloy,
Sriram Krishnamoorthy,
Michael A. Scarpulla,
Berardi Sensale-Rodriguez

Affiliations

Jacqueline Cooke: Department of Electrical and Computer Engineering, The University of Utah
Praneeth Ranga: Department of Electrical and Computer Engineering, The University of Utah
Jani Jesenovec: Institute of Materials Research, Washington State University
John S. McCloy: Institute of Materials Research, Washington State University
Sriram Krishnamoorthy: Materials Department, University of California, Santa Barbara
Michael A. Scarpulla: Department of Electrical and Computer Engineering, The University of Utah
Berardi Sensale-Rodriguez: Department of Electrical and Computer Engineering, The University of Utah

DOI: https://doi.org/10.1038/s41598-022-07242-z
Journal volume & issue: Vol. 12, no. 1
pp. 1 – 10

Abstract

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Abstract In this work, a systematic photoluminescence (PL) study on three series of gallium oxide/aluminum gallium oxide films and bulk single crystals is performed including comparing doping, epitaxial substrates, and aluminum concentration. It is observed that blue/green emission intensity strongly correlates with extended structural defects rather than the point defects frequently assumed. Bulk crystals or Si-doped films homoepitaxially grown on (010) β-Ga2O3 yield an intense dominant UV emission, while samples with extended structural defects, such as gallium oxide films grown on either (-201) β-Ga2O3 or sapphire, as well as thick aluminum gallium oxide films grown on either (010) β-Ga2O3 or sapphire, all show a very broad PL spectrum with intense dominant blue/green emission. PL differences between samples and the possible causes of these differences are analyzed. This work expands previous reports that have so far attributed blue and green emissions to point defects and shows that in the case of thin films, extended defects might have a prominent role in emission properties.

Published in Scientific Reports

ISSN: 2045-2322 (Online)
Publisher: Nature Portfolio
Country of publisher: United Kingdom
LCC subjects: Medicine; Science
Website: https://www.nature.com/srep/

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