Tungsten diselenide (WSe2) possesses extraordinary electronic properties forapplications in electronics, optoelectronics, and emerging exciton physics. Thesynthesis of monolayer WSe2 film is of topmost for device arra...Tungsten diselenide (WSe2) possesses extraordinary electronic properties forapplications in electronics, optoelectronics, and emerging exciton physics. Thesynthesis of monolayer WSe2 film is of topmost for device arrays and integratedcircuits. The monolayer WSe2 film has yet been reported by thermal chemicalvapor deposition (CVD) approach, and the nucleation mechanism remainsunclear. Here, we report a pre-seeding strategy for finely regulating the nucleidensity at an early stage and achieving a fully covered film after chemicalvapor deposition growth. The underlying mechanism is heterogeneous nucle-ation from the pre-seeding tungsten oxide nanoparticles. At first, we optimized the precursor concentration for pre-seeding. Besides, we confirmed the superi-ority of the pre-seeding method, compared with three types of substrate pre-treatments, including nontreatment, sonication in an organic solvent, andoxygen plasma. Eventually, the high-quality synthetic WSe2 monolayer filmexhibits excellent device performance in field-effect transistors and photodetec-tors. We extracted thermodynamic activation energy from the nucleation andgrowth data. Our results may shed light on the wafer-scale production ofhomogeneous monolayer films of WSe2, other 2D materials, and their van derWaals heterostructures.展开更多
基金Chinesisch-Deutsche Zentrum für Wissenschaftsförderung,Grant/Award Number:GZ 1400European Regional Development Fund,Grant/Award Number:CZ.02.1.01/0.0/0.0/16_019/0000853+9 种基金National Key Research and Development Program of China,Grant/Award Number:2017YFB0405400National Natural Science Foundation of China,Grant/Award Numbers:51802116,52022037,52071225,52002165Natural Science Foundation of Shandong Province,Grant/Award Number:ZR2019BEM040Taishan Scholars Project Special Funds,Grant/Award Number:tsqn201812083the Project of“20 items of University”of Jinan,Grant/Award Number:2018GXRC031the National Science CenterSouthern University of Science and Technologythe Innovation Project for Guangdong Provincial Department of Education,Grant/Award Number:2019KTSCX155Guangdong Provincial Key Laboratory of Catalysis,Grant/Award Number:2020B121201002Beijing National Laboratory for Molecular Science,Grant/Award Number:BNLMS202013。
文摘Tungsten diselenide (WSe2) possesses extraordinary electronic properties forapplications in electronics, optoelectronics, and emerging exciton physics. Thesynthesis of monolayer WSe2 film is of topmost for device arrays and integratedcircuits. The monolayer WSe2 film has yet been reported by thermal chemicalvapor deposition (CVD) approach, and the nucleation mechanism remainsunclear. Here, we report a pre-seeding strategy for finely regulating the nucleidensity at an early stage and achieving a fully covered film after chemicalvapor deposition growth. The underlying mechanism is heterogeneous nucle-ation from the pre-seeding tungsten oxide nanoparticles. At first, we optimized the precursor concentration for pre-seeding. Besides, we confirmed the superi-ority of the pre-seeding method, compared with three types of substrate pre-treatments, including nontreatment, sonication in an organic solvent, andoxygen plasma. Eventually, the high-quality synthetic WSe2 monolayer filmexhibits excellent device performance in field-effect transistors and photodetec-tors. We extracted thermodynamic activation energy from the nucleation andgrowth data. Our results may shed light on the wafer-scale production ofhomogeneous monolayer films of WSe2, other 2D materials, and their van derWaals heterostructures.
