# Maskless laser processing of graphene

## TL;DR

This paper demonstrates a maskless laser technique to selectively remove and pattern graphene on substrates, with control based on graphene thickness, using ultraviolet pulsed laser irradiation.

## Contribution

It introduces a novel maskless laser process for thickness-selective removal and patterning of graphene on SiO2/Si substrates.

## Key findings

- Threshold laser power depends on graphene thickness.
- Thickness-dependent removal enables selective patterning.
- Maskless laser patterning in air is feasible.

## Abstract

Graphene on a SiO$_2$/Si substrate was removed by ultraviolet pulsed laser irradiation. Threshold laser power density to remove graphene depended on the graphene thickness. The mechanism is discussed using kinetic energy of thermal expansion of the substrate surface. Utilizing the thickness dependence, thickness (or layer-number) selective process for graphene is demonstrated. Maskless patterning of graphene using laser irradiation in the air is also demonstrated.