On the Role of Water Vapor and Process Gasses in Low-Temperature Gold-Catalyzed Graphene Etching

TL;DR

This paper presents a low-temperature, scalable method for graphene patterning using gold catalysis in ambient air, emphasizing the role of water vapor and process parameters in controlling etch characteristics.

Contribution

It introduces a simple, ambient air-based etching technique for graphite at low temperatures, highlighting the necessity of water vapor and specific process conditions for controlled etching.

Findings

Water vapor is essential for the etching process.

Annealing in argon yields straight etch lines.

Optimal temperature (375°C) enables single-layer deep etching.

Abstract

The ability to pattern graphene at low temperatures in a scalable manner is one of the greatest challenges facing graphene industrial adoption today. We demonstrate a simple method for low-temperature gold-catalyzed etching of graphite with predictable characteristics using ambient air at $350-375^\circ$ C. The naturally occurring water vapor in ambient air is necessary for this reaction to occur. In addition, we characterize the etch characteristics as a function of process parameters. Ar annealing is required to obtain crystallographically straight etches, and $375^\circ$ C is required to obtain single-layer deep etching. We anticipate that this work can be adapted by future research to precisely control the shape of the etched areas, allowing for the simple low-temperature creation of nanoscale graphite features, and ultimately can be applied to single-layer graphene sheets for integrated device fabrication.