An innovative way of etching MoS2: Characterization and mechanistic investigation

TL;DR

This paper presents a controlled XeF2-based etching method for MoS2 that enables precise patterning and the creation of complex nanostructures, with potential extension to other 2D materials.

Contribution

It introduces a novel, controllable etching technique for MoS2 using XeF2, facilitating the fabrication of various nanostructures with uniform properties.

Findings

Monolayer MoS2 with uniform morphology achieved

Etched MoS2 exhibits Raman and photoluminescence similar to exfoliated material

Patterning of MoS2 into complex nanostructures demonstrated

Abstract

We report a systematic study of the etching of MoS2 crystals by using XeF2 as a gaseous reactant. By controlling the etching process, monolayer MoS2 with uniform morphology can be obtained. The Raman and photoluminescence spectra of the resulting material were similar to those of exfoliated MoS2. Utilizing this strategy, different patterns such as a Hall bar structure and a hexagonal array can be realized. Furthermore, the etching mechanism was studied by introducing graphene as an etching mask. We believe our technique opens an easy and controllable way of etching MoS2, which can be used to fabricate complex nanostructures, such as nanoribbons, quantum dots and transistor structures. This etching process using XeF2 can also be extended to other interesting two-dimensional crystals.