Line and Point Defects in MoSe2 Bilayer Studied by Scanning Tunneling Microscopy and Spectroscopy
Line and Point Defects in MoSe2 Bilayer Studied by Scanning Tunneling Microscopy and Spectroscopy
复制标题
通过扫描隧道显微镜和光谱研究 MoSe2 双层中的线和点缺陷
DOI：
10.1021/acsnano.5b02789
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发表时间：
2015-06-01
期刊：
影响因子：
17.1
通讯作者：
Xie, Maohai
中科院分区：
文献类型：
--
作者：
Liu, Hongjun;Zheng, Hao;Xie, Maohai
通过扫描隧道显微镜和光谱学 (STM/S) 研究了分子束外延 (MBE) 生长的双层 (BL) MoSe2 薄膜。与单层 (ML) 薄膜类似，在 BL MoSe2 的顶层和底层均观察到反转域边界 (DB) 缺陷网络，并且通常看到它们在空间上相关，使得一个在另一个之上。底层也有孤立的，在顶层没有伴生，STM/S 通过缺陷态的量子隧道穿过 MoSe2 ML 的势垒来检测。将 BL MoSe2 中的 DB 态与 ML 薄膜中的 DB 态进行比较，揭示了一些共同特征和差异。指出了缺陷态的量子限制。 STM/S 还观察到 BL MoSe2 中的点缺陷，其中证明了尖端感应电场对施主缺陷的电离。这些结果对于由 MoSe2 超薄层制成的器件具有重大的根本意义和实际意义。
Bilayer (BL) MoSe2 films grown by molecular-beam epitaxy (MBE) are studied by scanning tunneling microscopy and spectroscopy (STM/S). Similar to monolayer (ML) films, networks of inversion domain boundary (DB) defects are observed both in the top and bottom layers of BL MoSe2, and often they are seen spatially correlated such that one is on top of the other. There are also isolated ones in the bottom layer without companion in the top-layer and are detected by STM/S through quantum tunneling of the defect states through the barrier of the MoSe2 ML. Comparing the DB states in BL MoSe2 with that of ML film reveals some common features as well as differences. Quantum confinement of the defect states is indicated. Point defects in BL MoSe2 are also observed by STM/S, where ionization of the donor defect by the tip-induced electric field is evidenced. These results are of great fundamental interests as well as practical relevance of devices made of MoSe2 ultrathin layers.