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Change in polarity of zinc oxide films grown on sapphire substrates without insertion of any buffer layer

Published online by Cambridge University Press:  31 January 2011

Yutaka Adachi*
National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
Naoki Ohashi
National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
Tsuyoshi Ohnishi
National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
Takeshi Ohgaki
National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
Isao Sakaguchi
National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
Hajime Haneda
National Institute for Materials Science (NIMS), Tsukuba, Ibaraki 305-0044, Japan
Mikk Lippmaa
Institute of Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
a)Address all correspondence to this author. e-mail:
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We have investigated the polarity of zinc oxide (ZnO) and Al-doped ZnO films grown on (11¯20) and (0001) sapphire substrates, using coaxial impact collision ion scattering spectroscopy. The films grown by pulsed laser deposition with a nominally undoped ZnO ceramic target had a (000¯1) surface, whereas the films prepared with a 1 mol% Al-doped ZnO ceramic target had a (0001) surface. The usage of Al-doped and undoped targets caused no difference in the in-plane lattice orientation. Electron microscope observations revealed that polarity change due to doping occurred without the formation of any interfacial phase between ZnO and sapphire.

Copyright © Materials Research Society 2008

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