Wafer-Scale Films of Two-Dimensional Materials via Roll-to-Roll Mechanical Exfoliation

TL;DR

This paper presents a scalable roll-to-roll mechanical exfoliation method with controlled sliding to produce uniform wafer-scale 2D material films, enabling high-quality electronic device fabrication with minimal contamination.

Contribution

It introduces an improved, high-throughput exfoliation technique that achieves wafer-scale uniform 2D films suitable for electronic applications, surpassing previous methods in scalability and quality.

Findings

Successful fabrication of wafer-scale WSe2 phototransistors with high performance

Uniform nanosheet films achieved via controlled sliding exfoliation

Method is scalable, cost-effective, and preserves material quality

Abstract

In this study, we demonstrate an improved version of the roll-to-roll mechanical exfoliation method, incorporating a controlled sliding motion into the exfoliation process to achieve uniform nanosheet films of two-dimensional materials at wafer-scale. This scalable technique enables the fabrication of high-quality films suitable for electronic and optoelectronic applications. We validate the process by fabricating WSe2 phototransistors directly on the exfoliated films, achieving performance metrics comparable to the best reported devices based on electrochemically exfoliated material. The all-dry transfer method employed ensures minimal contamination and preserves the intrinsic properties of the material. This work highlights the potential of high-throughput mechanical exfoliation as a cost-effective and reliable route for large-scale production of 2D material-based devices.