期刊
NANO LETTERS
卷 16, 期 8, 页码 5213-5220出版社
AMER CHEMICAL SOC
DOI: 10.1021/acs.nanolett.6b02263
关键词
Transitional metal dichalcogenides; vacancies; optical properties; Raman scattering; electrical properties
类别
资金
- U.S. Department of Energy, Office of Science, Basic Energy Sciences (BES), Materials Sciences and Engineering Division
- U.S. Department of Energy, Office of Science, Basic Energy Sciences (BES), Scientific User Facilities Division
- Eugene P. Wigner Fellowship at Oak Ridge National Laboratory
- Laboratory Directed Research and Development Program of Oak Ridge National Laboratory
Defect engineering has been a critical step in controlling the transport characteristics of electronic devices, and the ability to create, tune, and annihilate defects is essential to enable the range of next-generation devices. Whereas defect formation has been well-demonstrated in three-dimensional semiconductors, similar exploration of the heterogeneity in atomically thin two-dimensional semiconductors and the link between their atomic structures, defects, and properties has not yet been extensively studied. Here, we demonstrate the growth of MoSe2-x single crystals with selenium (Se) vacancies far beyond intrinsic levels, up to similar to 20%, that exhibit a remarkable transition in electrical transport properties from n- to p-type character with increasing Se vacancy concentration. A new defect-activated phonon band at similar to 250 cm(-1) appears, and the A(1g) Raman characteristic mode at 240 cm(-1) softens toward similar to 230 cm(-1) which serves as a fingerprint of vacancy concentration in the crystals. We show that post-selenization using pulsed laser evaporated Se atoms can repair Se-vacant sites to nearly recover the (p)roperties of the pristine crystals. First-principles calculations reveal the underlying mechanisms for the corresponding vacancy induced electrical and optical transitions.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据