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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 21, Iss. 12 — Jun. 17, 2013
  • pp: 14131–14138

Effects of free electrons and quantum confinement in ultrathin ZnO films: a comparison between undoped and Al-doped ZnO

X.D. Li, T. P. Chen, P. Liu, Y. Liu, and K. C. Leong  »View Author Affiliations


Optics Express, Vol. 21, Issue 12, pp. 14131-14138 (2013)
http://dx.doi.org/10.1364/OE.21.014131


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Abstract

Band gaps and exciton binding energies of undoped and Al-doped ZnO thin films were determined from optical absorption measurement based on the Elliott’s exciton absorption theory. As compared to the undoped films, the doped films exhibit a band gap expansion and a reduction in the exciton binding energies due to the free electron screening effect, which suppresses the excitonic absorption and results in a blue shift of the absorption edge. The undoped and doped films show the same quantum size dependence, i.e. both the exciton binding energies and band gap energies increase with decreasing grain size of the oxides.

© 2013 OSA

OCIS Codes
(260.7190) Physical optics : Ultraviolet
(300.1030) Spectroscopy : Absorption
(310.6860) Thin films : Thin films, optical properties
(310.6188) Thin films : Spectral properties

ToC Category:
Thin Films

History
Original Manuscript: April 25, 2013
Revised Manuscript: May 23, 2013
Manuscript Accepted: May 23, 2013
Published: June 6, 2013

Citation
X.D. Li, T. P. Chen, P. Liu, Y. Liu, and K. C. Leong, "Effects of free electrons and quantum confinement in ultrathin ZnO films: a comparison between undoped and Al-doped ZnO," Opt. Express 21, 14131-14138 (2013)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-21-12-14131


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