# Defect-Moderated Oxidative Etching of MoS2

## TL;DR

This paper introduces a defect-mediated oxidative etching method for MoS2, enabling precise, selective removal of monolayer and bilayer regions through controlled defect creation and heating in air.

## Contribution

The study presents a novel, simple technique for selective etching of MoS2 using defect activation via He+ ion treatment followed by air oxidation.

## Key findings

- Effective selective etching of MoS2 achieved
- Defect pre-treatment enhances etching efficiency
- High spatial specificity in etching process

## Abstract

We report a simple technique for the selective etching of bilayer and monolayer MoS$_2$. In this work, chosen regions of MoS$_2$ were activated for oxygen adsorption and reaction by the application of low doses of He$^+$ at 30 keV in a gas ion microscope. Raman spectroscopy, optical microscopy and scanning electron microscopy were used to characterize both the etched features and the remaining material. It has been found that by using a pre-treatment to introduce defects, MoS$_2$ can be etched very efficiently and with high region specificity by heating in air.