The inherent difficulties in handling and producing graphene have been a major barrier in developing such devices. Conventional microfabrication methods are mostly based on chemical etching processes, which often involve tedious masking and aligning steps. Here, we report a novel mechanical fast-prototyping method to fabricate graphene-based electronic structures on few-layer graphene (FLG) using focused-ion beam (FIB). FIB is a versatile tool and FIB-assisted deposition and milling processes feature mask-free patterning, quick turnaround time as well as high precision. Specifically, in this study, the parameters of FIB are well controlled. The platinum wire, which is induced from the gaseous precursors by the fined focused gallium ions of low energy, is conveniently deposited on the substrate to connect FLG. The measured channel resistance of around 50 k indicates good electrical contact between platinum wire and FLG. With the computer controlled alignment and patterning, the accuracy of deposition and milling can be as high as 200 nm. For the milling process, 2-D ribbon structures can be easily produced by clean cutting the patterned area with high ion energy and longer milling time. We also tried to fine tune FIB to machine 3D graphene structures by selectively milling 1~2 layers off.
Journal: TechConnect Briefs
Volume: 2, Nanotechnology 2012: Electronics, Devices, Fabrication, MEMS, Fluidics and Computational (Volume 2)
Published: June 18, 2012
Pages: 502 - 505
Industry sectors: Advanced Materials & Manufacturing | Sensors, MEMS, Electronics
Topics: Advanced Manufacturing, Nanoelectronics