Point defects induced work function modulation of β-Ga2O3

Research output: Contribution to journalArticle


  • B. R. Tak
  • Sheetal Dewan
  • Anshu Goyal
  • Ravi Pathak
  • Vinay Gupta
  • A. K. Kapoor
  • S. Nagarajan
  • R. Singh

Research units

  • Indian Institute of Technology, Delhi
  • University of Delhi
  • Solid State Physics Laboratory India


Effect of point defects such as vacancies and interstitials on the work function of β-Ga2O3 thin films grown by pulsed laser deposition was investigated. Relative change in Ag 3 and Ag 6 Raman phonon modes indicated formation of oxygen and gallium vacancy defects. The surface potential mapping of Ga2O3 thin films was performed by Kelvin probe force microscopy. Analytical calculations showed variation in work function with oxygen pressure. The work function values at extreme growth pressure conditions were found to be very high. Hence, Fermi level was pinned at the mid-gap energy in both oxygen-deficient condition and oxygen-rich conditions which is attributed to oxygen and gallium vacancy defects. This mechanism of controlling Fermi level pinning in β-Ga2O3 paves the way to fabricate high performance electronic devices.


Original languageEnglish
Pages (from-to)973-978
Number of pages6
JournalApplied Surface Science
Publication statusPublished - 28 Jan 2019
MoE publication typeA1 Journal article-refereed

    Research areas

  • GaO, Point defects, Raman phonon modes, Valence band spectra, Work function

ID: 28748631