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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 18, Iss. 16 — Aug. 2, 2010
  • pp: 16360–16369

Thermoreflectance characterization of β-Ga2O3 thin-film nanostrips

Ching-Hwa Ho, Chiao-Yeh Tseng, and Li-Chia Tien  »View Author Affiliations

Optics Express, Vol. 18, Issue 16, pp. 16360-16369 (2010)

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Nanostructure of β-Ga2O3 is wide-band-gap material with white-light-emission function because of its abundance in gap states. In this study, the gap states and near-band-edge transitions in β-Ga2O3 nanostrips have been characterized using temperature-dependent thermoreflectance (TR) measurements in the temperature range between 30 and 320 K. Photoluminescence (PL) measurements were carried to identify the gap-state transitions in the β-Ga2O3 nanostrips. Experimental analysis of the TR spectra revealed that the direct gap (E0) of β-Ga2O3 is 4.656 eV at 300 K. There are a lot of gap-state and near-band-edge (GSNBE) transitions denoted as ED3, EW1, EW2, EW3, ED2, E DB ex , EDB, ED1, E0, and E0′ can be detected in the TR and PL spectra at 30 K. Transition origins for the GSNBE features in the β-Ga2O3 nanostrips are respectively evaluated. Temperature dependences of transition energies of the GSNBE transitions in the β-Ga2O3 nanostrips are analyzed. The probable band scheme for the GSNBE transitions in the β-Ga2O3 nanostrips is constructed.

© 2010 OSA

OCIS Codes
(160.4760) Materials : Optical properties
(160.6000) Materials : Semiconductor materials
(300.6380) Spectroscopy : Spectroscopy, modulation
(300.6470) Spectroscopy : Spectroscopy, semiconductors

ToC Category:

Original Manuscript: May 17, 2010
Revised Manuscript: July 4, 2010
Manuscript Accepted: July 12, 2010
Published: July 20, 2010

Ching-Hwa Ho, Chiao-Yeh Tseng, and Li-Chia Tien, "Thermoreflectance characterization of β-Ga2O3 thin-film nanostrips," Opt. Express 18, 16360-16369 (2010)

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