Aligned graphene nanoribbon (GNR) arrays were made by unzipping of aligned
single-walled and few-walled carbon nanotube (CNT) arrays. Nanotube unzipping
was achieved by a polymer-protected Ar plasma etching method, and the resulting
nanoribbon array was transferred onto any substrates. Atomic force microscope
(AFM) imaging and Raman mapping on the same CNTs before and after unzipping
confirmed that ~80% of CNTs were opened up to form single layer sub-10 nm GNRs.
Electrical devices made from the GNRs (after annealing in H2 at high
temperature) showed on/off current (Ion/Ioff) ratios up to 103 at room
temperature, suggesting semiconducting nature of the narrow GNRs. Novel GNR-GNR
and GNR-CNT crossbars were fabricated by transferring GNR arrays across GNR and
CNT arrays, respectively. The production of ordered graphene nanoribbon
architectures may allow for large scale integration of GNRs into
nanoelectronics or optoelectronics.Comment: published in Nano Researc