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arXiv · 1602.06639

Laser-assisted Oxidation of Multi-layer Tungsten Diselenide Nanosheets

Cheng Tan·Yingnan Liu·Harry Chou·Joon-Seok Kim·Di Wu·Deji Akinwande·keji Lai
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Abstract

We report the structural and electrical characterization of tungsten oxides formed by illuminating multi-layer tungsten diselenide (WSe2) nanosheets with an intense laser beam in the ambient environment. A noninvasive microwave impedance microscope (MIM) was used to perform electrical imaging of the samples. The local conductivity ~100 S/m of the oxidized product, measured by the MIM and conventional transport experiments, is much higher than that of the pristine WSe2, suggesting the formation of sub-stoichiometric WO3-x polycrystals with n-type carriers. With further efforts to improve the conductivity of the oxides, the laser-assisted oxidation process may be useful for patterning conductive features on WSe2 or forming electrical contacts to various transition metal dichalcogenides.

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Cheng Tan, Yingnan Liu, Harry Chou, Joon-Seok Kim, Di Wu, Deji Akinwande, keji Lai. 2016-02-22. Laser-assisted Oxidation of Multi-layer Tungsten Diselenide Nanosheets. https://doi.org/10.1063/1.4942802

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