Large-Scale Ultrafast Strain Engineering of CVD-Grown Two-Dimensional Materials on Strain Self-Limited Deformable Nanostructures toward Enhanced Field-Effect Transistors.

Huang, Zheng; Lu, Nan; Wang, Zifeng; Xu, Shuoheng; Guan, Jie; Hu, Yaowu · Nano Lett · 2022

basic_science · Level V

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Abstract

Strain engineering of 2D materials is capable of tuning the electrical and optical properties of the materials without introducing additional atoms. Here, a method for large-scale ultrafast strain engineering of CVD-grown 2D materials is proposed. Locally nonuniform strains are introduced through the cooperative deformation of materials and metal@metal oxide nanoparticles through cold laser shock. The tensile strain of MoS<sub>2</sub> changes and the band gap decreases after laser shock. The mechanism of the ultrafast straining is investigated by MD simulations. MoS<sub>2</sub> FETs were fabricated, and the field-effect mobility of devices could be increased from 1.9 to 44.5 cm<sup>2</sup> V<sup>-1</sup> s<sup>-1</sup> by adjusting the strain level of MoS<sub>2</sub>. This is currently the maximum value of MoS<sub>2</sub> FETs grown by CVD with SiO<sub>2</sub> as the dielectric. As a large-scale and ultrafast manufacturing method, laser shock provides a universal strategy for large-scale adjustment of 2D material strain, which will help to promote the manufacturing of 2D nanoelectronic devices.