Monolayer Graphene Grown on Nanoscale Pt Films Deposited on TiO₂ Substrates for Micro- and Nanoelectromechanical Systems

This study presents chemical vapor deposition (CVD) growth of high-quality monolayer graphene on 100 nm-thick Pt thin films deposited on TiO2-coated silicon wafers. Conventional graphene growth on Pt thin films using CVD requires relatively thick films because of potential dewetting issues, which limits fabrication integration for nano-/microelectromechanical system (NEMS/MEMS) devices. Additional metal interlayers are commonly introduced to provide good adhesion between the Pt thin film and the substrate to achieve reliable graphene growth on thinner thin films. However, growing high-quality graphene on the Pt films with a thickness of less than 100 nm has still not been demonstrated because of dewetting issues. In this work, we introduce TiO2 as an adhesion layer for Pt on a Si substrate for graphene growth and show that using this adhesion layer, we are able to achieve large-area coverage of high-quality graphene without significant surface dewetting of a 100 nm Pt thin-film substrate. These results are confirmed by time-of-flight secondary ion mass spectrometry and Raman spectroscopy measurements. Our results show that graphene growth on Pt thin films can be more reliable using TiO2 as an adhesion layer and provides a guide for integration of growth of graphene onto the NEMS/MEMS device during the fabrication process.