  Atomically precise graphene nanoribbons are a promising emerging class of
designer quantum materials with electronic properties that are tunable by
chemical design. However, many challenges remain in the device integration of
these materials, especially regarding contacting strategies. We report on the
device integration of uniaxially aligned and non-aligned 9-atom wide armchair
graphene nanoribbons (9-AGNRs) in a field-effect transistor geometry using
electron beam lithography-defined graphene electrodes. This approach yields
controlled electrode geometries and enables higher fabrication throughput
compared to previous approaches using an electrical breakdown technique.
Thermal annealing is found to be a crucial step for successful device operation
resulting in electronic transport characteristics showing a strong gate
dependence. Raman spectroscopy confirms the integrity of the graphene
electrodes after patterning and of the GNRs after device integration. Our
results demonstrate the importance of the GNR-graphene electrode interface and
pave the way for GNR device integration with structurally well-defined
electrodes.
