We demonstrate a simple surface engineering method for fabricating graphene transistors by using hydrophobizing stamps. By simply contact-printing hydrophobizing stamp that is made with polydimethylsiloxane (PDMS) on a standard silicon substrate for a certain contact-time, it was possible to control the contact angle of the substrate and electrical characteristics of the graphene transistors supported on the substrate. Moreover, graphene transistors supported on the engineered silicon substrate showed improved performances, including an increase in carrier mobility and loss of hysteresis. As a proof-of-concept experiment, a simple logic gate operation was demonstrated by connecting a pristine graphene device with an interface-engineered device.
Keywords: graphene; hydrophobizer; interface engineering; polydimethylsiloxane; transistor.