Polarity control of ZnO on sapphire by varying the MgO buffer layer thickness
Polarity control of ZnO on sapphire by varying the MgO buffer layer thickness
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DOI：
10.1063/1.1759377
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发表时间：
2004-05-31
影响因子：
4
通讯作者：
Yao, T
中科院分区：
文献类型：
--
作者：
Kato, H;Miyamoto, K;Yao, T
采用等离子体辅助分子束外延技术在c面蓝宝石衬底上生长了具有MgO缓冲层的极性可控ZnO薄膜。会聚束电子衍射结果表明，当MgO层厚度大于3 nm时，发生Zn-极性（+c）生长，而当MgO层厚度小于2 nm时，发生O-极性（-c）生长。反射式高能电子衍射结果表明，MgO薄膜的生长模式为Stranski-Krastanov模式，当薄膜厚度大于1 nm时，薄膜的生长模式发生了从二维到三维的转变。总之，极性转换显然发生由于不同的原子结构之间的润湿层和岛的MgO。(C)2004年，美国物理学会。
Polarity-controlled ZnO films with an MgO buffer layer were grown on c-plane sapphire by plasma-assisted molecular-beam epitaxy. Convergent beam electron diffraction results showed that Zn-polarity (+c) growth occurred when the MgO layer was thicker than 3 nm, whereas O-polarity (-c) growth occurred when the layer was less than 2 nm. Reflection high-energy electron diffraction results revealed that MgO growth was Stranski-Krastanov mode, and that the growth mode transition from two- to three-dimensional occurred when the layer was thicker than 1 nm. In conclusion, polarity conversion apparently occurs due to the different atomic structure between the wetting layer and islands of MgO. (C) 2004 American Institute of Physics.