Pulsed laser deposited Be Zn-x(1-x) O1-ySy quaternary alloy films: structure, composition, and band gap bowing
Pulsed laser deposited Be Zn-x(1-x) O1-ySy quaternary alloy films: structure, composition, and band gap bowing
复制标题
脉冲激光沉积 Be Zn-x(1-x) O1-ySy 四元合金薄膜：结构、成分和带隙弯曲
DOI：
10.1016/j.apsusc.2017.10.068
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发表时间：
2018
影响因子：
6.7
通讯作者：
He Yunbin
中科院分区：
文献类型：
--
作者：
Zhang Wuzhong;Xu Maji;Zhang Mi;Cheng Hailing;Li Mingkai;Zhang Qingfeng;Lu Yinmei;Chen Jingwen;Chen Changqing;He Yunbin
本文首次采用脉冲激光沉积技术在蓝宝石衬底上成功地制备了c轴择优取向的BexZn1-xO1-ySy(BeZnOS)四元合金薄膜。通过适当调节沉积过程中的氧气压力，生长的薄膜具有单相的六方结构和良好的结晶质量。由于较小的Be2+同时取代阳离子≤和较大的S2≥同时取代阴离子O2−，S在BexZn1-xO1-y四元系合金中的固溶度显著增加(y−=0.17ory≥=0.35)。此外，由于BeO的引入，四元薄膜比S含量相近的三元薄膜具有更宽的禁带宽度。随着氧分压从0.05~6分压的增加，BeZnOS的带隙呈现出有趣的弯曲行为。禁带宽度的变化范围在3.55~3.10 eV之间。具有宽禁带特性的BeZnOS薄膜在制作紫外光探测器等光电子器件方面具有潜在的应用前景。
In this work,c-axis preferentially oriented BexZn1-xO1-ySy(BeZnOS) quaternary alloy films were prepared successfully onc-plane sapphire by pulsed laser deposition for the first time. By appropriate adjustment of O2pressure during the deposition, the grown films exhibited a single-phase hexagonal structure and good crystalline quality. The solid solubility of S in BexZn1-xO1-ySyquaternary alloy was significantly expanded (y≤ 0.17 ory≥ 0.35) as a result of simultaneous substitution of cation Zn2+by smaller Be2+and anion O2−by bigger S2−. Besides, due to the introduction of BeO with a wide band gap, BeZnOS quaternary films exhibited wider band gaps than the ternary ZnOS films with similar S contents. As the O2pressure increased from 0.05 Pa to 6 Pa, the band gap of BeZnOS displayed an interesting bowing behavior. The variation range of the band gap was between 3.55 eV and 3.10 eV. The BeZnOS films with a wide band gap show potential applications in fabricating optoelectronic devices such as UV-detectors.