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Cubic ZnxMg1−xO thin films grown by plasma-assisted molecular-beam epitaxy for optoelectronic applications

Published online by Cambridge University Press:  31 January 2011

J.W. Mares ,
R.C. Boutwell ,
A. Scheurer  and
W.V. Schoenfeld
W.V. Schoenfeld*
Affiliation:
CREOL/The College of Optics and Photonics, University of Central Florida, Orlando, Florida 32816
*
b)This author was an editor of this journal during the review and decision stage. For the JMR policy on review and publication of manuscripts authored by editors, please refer to http://www.mrs.org/jmr_policy
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Abstract

Heteroepitaxial ZnxMg1−xO thin films were grown on lattice-matched MgO (100) substrates using radiofrequency plasma-assisted molecular-beam epitaxy. High-quality epilayers with zinc concentrations ranging from x = 0 (MgO) to x = 0.65 were grown and characterized optically, structurally, and electrically. The ZnxMg1−xO films were found to maintain the rocksalt cubic (B1) crystal structure for concentrations z < 0.65, with a linear dependence of lattice constant on Zn concentration. X-ray diffraction (XRD) also revealed the emergence of phase segregation into wurtzite (B4) phase for the highest concentration film. The band gap energy of the films was successfully varied from 4.9 to 6.2 eV (253–200 nm), showing a linear relationship with Zn concentration. The strictly cubic films exhibit roughness on the order of 10 Å and resistivities of approximately 106 Ω·cm.

Keywords

Molecular beam epitaxy (MBE)Thin filmOxide
Type
Articles
Information
Journal of Materials Research , Volume 25 , Issue 6 , June 2010 , pp. 1072 - 1079
Copyright
Copyright © Materials Research Society 2010

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References

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