Structural and optical properties of single-phase ZnO1鈭?/sub>xSx alloy films epitaxially grown by pulsed laser deposition
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- 作者：Yunbin He ; Lei Zhang ; Liangheng Wang ; Mingkai Li ; Xunzhong Shang ; Xiong Liu ; Yinmei Lu ; Bruno K. Meyer
- 关键词：ZnOS alloy films ; Pulsed laser deposition ; Epitaxial growth ; Lattice parameters ; Band gap
- 刊名：Journal of Alloys and Compounds
- 出版年：25 February, 2014
- 年：2014
- 卷：587
- 期：Complete
- 页码：369-373
- 全文大小：1630 K
文摘
We report on a detailed investigation of the structural and optical properties of single crystalline ZnO1鈭?/sub>xSx thin films, placing emphasis on the elucidation of the correlation of the band gap and lattice parameters, particularly the lattice constant a, with the S content in the alloy films. High-quality ZnO1鈭?/sub>xSx thin films with different S concentrations Xs (0 猢?#xA0;Xs 猢?#xA0;0.18) were grown epitaxially on c-plane sapphire substrates by pulsed laser deposition using a ZnS ceramic target with varying O2 partial pressures. X-ray diffraction studies revealed that all grown ZnO1鈭?/sub>xSx thin films have a single-phase wurtzite structure. With increasing Xs value from 0 to 0.18, both lattice constants c and a expand monotonically from 5.204 to 5.366 脜 and from 3.255 to 3.329 脜, respectively, while the optical band gap shrinks from 3.27 to 2.92 eV with a bowing parameter of 2.91 eV. Based on these information, ZnOS/MgZnO heterostructures that have a perfect in-plane lattice match and a maximum barrier height can be proposed, which might eventually lead to new optoelectronic devices with superior performance.