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

Nano Lett. 2022 Sep 28;22(18):7734-7741. doi: 10.1021/acs.nanolett.2c01559. Epub 2022 Aug 11.

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 MoS2 changes and the band gap decreases after laser shock. The mechanism of the ultrafast straining is investigated by MD simulations. MoS2 FETs were fabricated, and the field-effect mobility of devices could be increased from 1.9 to 44.5 cm2 V-1 s-1 by adjusting the strain level of MoS2. This is currently the maximum value of MoS2 FETs grown by CVD with SiO2 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.

Keywords: CVD monolayer MoS2, metal nanoparticles; laser-shock-induced cooperative deformation; strain engineering.