Visibility study of graphene multilayer structures

TL;DR

This study investigates how to improve the optical visibility of graphene multilayers on various substrates by using resist coatings, enabling better fabrication of graphene-based electronic and optoelectronic devices.

Contribution

It introduces a method of using resist coatings to enhance graphene visibility on semiconductor and metallic substrates, verified through experiments.

Findings

Resist coating improves graphene visibility on diverse substrates.

Optimal resist thickness is key to contrast enhancement.

Experimental verification on quartz and NiFe-coated Si substrates.

Abstract

The visibility of graphene sheets on different types of substrates has been investigated both theoretically and experimentally. Although single layer graphene is observable on various types of dielectrics under an optical microscope, it is invisible when it is placed directly on most of the semiconductor and metallic substrates. We show that coating of a resist layer with optimum thickness is an effective way to enhance the contrast of graphene on various types of substrates and makes single layer graphene visible on most semiconductor and metallic substrates. Experiments have been performed to verify the results on quartz and NiFe-coated Si substrates. The results obtained will be useful for fabricating graphene-based devices on various types of substrates for electronics, spintronics and optoelectronics applications.