Nanomechanical and Macrotribological Properties of CVD-Grown Graphene as a Middle Layer between Metal Pt Cylinders and SiO2/Si Substrate

Abstract

The CVD-grown graphene as a middle layer was introduced between Pt cylinders and SiO2/Si to extend the application of graphene for improving the wear performance of microelectromechanical systems. Periodic arrays of Pt cylinders were prepared on the graphene/SiO2/Si (Pt/graphene) and SiO2/Si substrate (Pt/SiO2) using the magnetron sputtering technique. To characterize Pt/graphene and Pt/SiO2, nanoindentation and macrotribological tests were performed. The results showed that the friction coefficient was lower and the wear lifetime of Pt/graphene was longer than those of Pt/SiO2. Graphene, as a middle layer, was not only observed to have significant influence on the mechanical properties (i.e., microhardness and elastic modulus), but also found to improve the adhesive strength between SiO2/Si and Pt cylinders.