EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Atomically precise, bottom-up-synthesized graphene nanoribbons (GNRs) have attracted strong interest from researchers worldwide as they constitute an emerging class of quantum designer materials, ideally suited for future electronic devices. Some of the major challenges towards their exploitation, however, is their reliable contacting due to their small size (<50 nm), as well as the preservation of their physical properties upon device integration. In this presentation, I will cover our recent experimental efforts in contacting GNRs using various field-effect transistor device geometries using graphene-based electrodes. One of our important findings is the observation of single-electron transistor behavior at cryogenic temperature, yielding addition energies in the range of 200-500 meV, comparable to DFT calculations. I will also introduce Raman spectroscopy as a highly sensitive method for the characterization of GNRs, in particular for investigating their width, length, and structural integrity. The latter two properties are critical for device integration, and we will show how these two can be assessed using a length-dependent, Raman-active low-energy vibrational mode that is present in all armchair GNR families. We demonstrate that this mode is a sensitive probe for the overall structural integrity of the ribbons and their interaction with technologically relevant substrates.