説明
<jats:title>Abstract</jats:title><jats:p>Precise doping-profile engineering in van der Waals heterostructures is a key element to promote optimal device performance in various electrical and optical applications with two-dimensional layered materials. Here, we report tungsten diselenide- (WSe<jats:sub>2</jats:sub>) based pure vertical diodes with atomically defined p-, i- and n-channel regions. Externally modulated p- and n-doped layers are respectively formed on the bottom and the top facets of WSe<jats:sub>2</jats:sub> single crystals by direct evaporations of high and low work-function metals platinum and gadolinium, thus forming atomically sharp p–i–n heterojunctions in the homogeneous WSe<jats:sub>2</jats:sub> layers. As the number of layers increases, charge transport through the vertical WSe<jats:sub>2</jats:sub> p–i–n heterojunctions is characterized by a series of quantum tunneling events; direct tunneling, Fowler–Nordheim tunneling, and Schottky emission tunneling. With optimally selected WSe<jats:sub>2</jats:sub> thickness, our vertical heterojunctions show superb diode characteristics of an unprecedentedly high current density and low turn-on voltages while maintaining good current rectification.</jats:p>
収録刊行物
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- Nature Communications
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Nature Communications 9 (1), 5371-, 2018-12-18
Springer Science and Business Media LLC