Nanofabrication of graphene field-effect transistors by thermal scanning probe lithography

The development of a scalable and cost-effective nanofabrication method is of key importance for future advances in nanoelectronics. Thermal scanning probe lithography (t-SPL) is a growing nanopatterning method with potential for parallelization, offering unique capabilities that make it an attractive candidate for industrial nanomanufacturing. Here, we demonstrate the possibility to apply t-SPL for the fabrication of graphene devices. In particular, we use t-SPL to produce high performing graphene-based field effect transistors (FETs). The here described t-SPL process includes the fabrication of high-quality metal contacts, as well as patterning and etching of graphene to define the active region of the device. The electrical measurements on the t-SPL fabricated FETs indicate a symmetric conductance at the Dirac point and a low specific contact resistance without the use of any contact engineering strategy. The entire t-SPL nanofabrication process is performed without the need for masks, and in ambient conditions. Furthermore, thanks to the t-SPL in situ simultaneous patterning and imaging capability, no markers are required. These features substantially decrease fabrication time and cost.