Controlled Growth of Zn-Polar ZnO Films on Al-Terminated α-Al2O3(0001) Surface by Using Wurtzite MgO Buffer
YUAN Hong-Tao1, LIU Yu-Zi1, WANG Xi-Na1, LI Han-Dong1, WANG Yong1, ZENG Zhao-Quan1, MEI Zeng-Xia1, DU Xiao-Long1, JIA Jin-Feng2, XUE Qi-Kun2,1, ZHANG Ze3
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 1000802Department of Physics, Tsinghua University, Beijing 1000843Beijing University of Technology, Beijing 100022
Controlled Growth of Zn-Polar ZnO Films on Al-Terminated α-Al2O3(0001) Surface by Using Wurtzite MgO Buffer
1Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 1000802Department of Physics, Tsinghua University, Beijing 1000843Beijing University of Technology, Beijing 100022
摘要The controlled growth of Zn-polar ZnO films on Al-terminated αAl2O3 (0001) substrates is investigated by the radio-frequency plasma-assisted molecular beam epitaxy method. Prior to the growth, αAl2O3 (0001) surface is modified by an ultrathin MgO layer, which serves as a uniform template for epitaxy of Zn-polar ZnO films. The microstructures of ZnO/MgO/Al2O3 interface are investigated by in-situ reflection high-energy electron diffraction observations and ex-situ high-resolution transmission electron microscopy characterization. It is found that under Mg-rich condition, the achievement of the wurtzite MgO ultrathin layer plays a key role in the subsequent growth of Zn-polar ZnO. An interfacial atomic model is proposed to explain the mechanism of polarity selection of both MgO and ZnO films.
Abstract：The controlled growth of Zn-polar ZnO films on Al-terminated αAl2O3 (0001) substrates is investigated by the radio-frequency plasma-assisted molecular beam epitaxy method. Prior to the growth, αAl2O3 (0001) surface is modified by an ultrathin MgO layer, which serves as a uniform template for epitaxy of Zn-polar ZnO films. The microstructures of ZnO/MgO/Al2O3 interface are investigated by in-situ reflection high-energy electron diffraction observations and ex-situ high-resolution transmission electron microscopy characterization. It is found that under Mg-rich condition, the achievement of the wurtzite MgO ultrathin layer plays a key role in the subsequent growth of Zn-polar ZnO. An interfacial atomic model is proposed to explain the mechanism of polarity selection of both MgO and ZnO films.
YUAN Hong-Tao;LIU Yu-Zi;WANG Xi-Na;LI Han-Dong;WANG Yong;ZENG Zhao-Quan;MEI Zeng-Xia;DU Xiao-Long;JIA Jin-Feng;XUE Qi-Kun;ZHANG Ze. Controlled Growth of Zn-Polar ZnO Films on Al-Terminated α-Al2O3(0001) Surface by Using Wurtzite MgO Buffer[J]. 中国物理快报, 2007, 24(8): 2408-2411.
YUAN Hong-Tao, LIU Yu-Zi, WANG Xi-Na, LI Han-Dong, WANG Yong, ZENG Zhao-Quan, MEI Zeng-Xia, DU Xiao-Long, JIA Jin-Feng, XUE Qi-Kun, ZHANG Ze. Controlled Growth of Zn-Polar ZnO Films on Al-Terminated α-Al2O3(0001) Surface by Using Wurtzite MgO Buffer. Chin. Phys. Lett., 2007, 24(8): 2408-2411.
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