title: Large-area synthesis of highly crystalline WSe(2) monolayers and device applications.
abstract: The monolayer transition metal dichalcogenides have recently attracted much attention owing to their potential in valleytronics, flexible and low-power electronics, and optoelectronic devices. Recent reports have demonstrated the growth of large-size two-dimensional MoS2 layers by the sulfurization of molybdenum oxides. However, the growth of a transition metal selenide monolayer has still been a challenge. Here we report that the introduction of hydrogen in the reaction chamber helps to activate the selenization of WO3, where large-size WSe2 monolayer flakes or thin films can be successfully grown. The top-gated field-effect transistors based on WSe2 monolayers using ionic gels as the dielectrics exhibit ambipolar characteristics, where the hole and electron mobility values are up to 90 and 7 cm(2)/Vs, respectively. These films can be transferred onto arbitrary substrates, which may inspire research efforts to explore their properties and applications. The resistor-loaded inverter based on a WSe2 film, with a gain of ∼13, further demonstrates its applicability for logic-circuit integrations.
authors: Institute of Atomic and Molecular Sciences, Academia Sinica , Taipei 106, Taiwan.
authors: Jing-Kai
authors: JK
authors: Huang
authors: Jiang
authors: J
authors: Pu
authors: Chang-Lung
authors: CL
authors: Hsu
authors: Ming-Hui
authors: MH
authors: Chiu
authors: Zhen-Yu
authors: ZY
authors: Juang
authors: Yung-Huang
authors: YH
authors: Chang
authors: Wen-Hao
authors: WH
authors: Chang
authors: Yoshihiro
authors: Y
authors: Iwasa
authors: Taishi
authors: T
authors: Takenobu
authors: Lain-Jong
authors: LJ
authors: Li