Selective Area Growth and Transfer of High Optical Quality MoS2 Layers

Abstract

AbstractThis study demonstrates that monolayer molybdenum disulfide (MoS2) can be grown on selective areas of a substrate by creating isolated microcavity reactors throughout the substrate in a chemical vapor deposition (CVD) process. The obtained MoS2 in the confined areas can be tuned from isolated triangular domains of few tens of microns to a continuous film with different thicknesses by modulating the growth parameters. In contrast, the growth on the open areas of the substrate leads to an inhomogeneous film. Using the confined‐CVD approach, the area‐selective growth of MoS2 domains and films on arbitrary substrates such as SiO2/Si, sapphire, gold‐patterned SiO2/Si substrates, and SiNx‐membrane‐supported TEM grid is shown. Raman and photoluminescence spectroscopy studies reveal that the confined‐CVD‐derived MoS2 layers have high crystal quality and superior optical performance when compared to mechanically exfoliated flakes. A novel and efficient methodology is further introduced for the selective transfer of the confined‐growth areas to pre‐patterned substrates, therefore allowing multiple use of a single growth sample. Finally, field‐effect transistor devices are made on individual domains and mobilities up to ≈6.8 cm2 V−1 s−1 measured. The confined‐CVD approach and the selective area transfer presented here can be implemented on other transition metal dichalcogenides and 2D materials in general.