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

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.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 25, 2022
Source ID
10.1038/s41598-022-07242-z

Entities

People

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

Organizations

  • Air Force Office of Scientific Research

Tags

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Semiconductor Device Technology

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene