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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 21, Iss. 21 — Oct. 21, 2013
  • pp: 24599–24610

Effects of crystallinity and point defects on optoelectronic applications of β-Ga2O3 epilayers

Parvaneh Ravadgar, Ray-Hua Horng, Shu-De Yao, Hsin-Ying Lee, Bing-Rui Wu, Sin-Liang Ou, and Li-Wei Tu  »View Author Affiliations

Optics Express, Vol. 21, Issue 21, pp. 24599-24610 (2013)

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This study evaluates the effect of crystallinity and point defects on time-dependent photoresponsivity and the cathodoluminescence (CL) properties of β-Ga2O3 epilayers. A synchrotron high-resolution X-ray technique was used to understand the crystalline structure of samples. Rutherford backscattering spectroscopy was used to determine the net chemical composition of the samples to examine the type and ratio of their possible point defects. The results show that in functional time-dependent photoresponsivity of photodetectors based on β-Ga2O3 epilayers, point defects contribution overcomes the contribution of crystallinity. However, the crystalline structure affects the intensities and emission regions of CL spectra more than point defects.

© 2013 Optical Society of America

OCIS Codes
(250.0250) Optoelectronics : Optoelectronics
(310.0310) Thin films : Thin films

ToC Category:
Thin Films

Original Manuscript: August 21, 2013
Revised Manuscript: September 27, 2013
Manuscript Accepted: September 30, 2013
Published: October 7, 2013

Parvaneh Ravadgar, Ray-Hua Horng, Shu-De Yao, Hsin-Ying Lee, Bing-Rui Wu, Sin-Liang Ou, and Li-Wei Tu, "Effects of crystallinity and point defects on optoelectronic applications of β-Ga2O3 epilayers," Opt. Express 21, 24599-24610 (2013)

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