Transport at Nanoscale Interfaces

Hybrid Nanoscale Interfaces

A widely used technique to produce large scale high-quality graphene is chemical vapor deposition (CVD). With our home- built setup, we produce square-centimeters of continuous graphene films as well as isolated graphene grains for which we are able to tune the form (hexagon- / star-shape) and size (from tens of micrometers to millimetre scale). [1]

Involved people: Furrer Roman, Oswald Jacopo, Schmuck Oliver, Muff Rico, Andre Kupferschmid, Jonas Gartmann

The key advantages of CVD graphene respect exfoliated are: 
  1. Large scale
  2. the wide choice of growth substrate and gas precursors.
 
We characterize our graphene films and the transfer process using large area Raman mapping, optical microscope, AFM, XPS, LEEM and electrical transport measurements [1,2]. Ultimately, it is used in a variety of nanoelectronic application as the main material of interest [3] or as an electrode material [4,5].
Automatisation

To get a reproducable, stable recipe and a more easy process, we automated our CVD growth process.
Optical Microscope
Images of full-coverage graphene, transferred on silicon substrate, grown on dif-ferent copper foils, contrast enhanced.
We have clean, large scale graphene (e.g. see above picture of graphene on 10x10mm testdevice). 
 
With enhanced parameters, we can better visualize bilayers and contaminations then on most commonily seen optical microscope images (compare left to right on the above picture.)
Raman

Raman spectra of transferred, full coverage graphene 
 
Single-spectras (200206-LG-P2)
 


Raman map of structured graphene bar (top left to bot right: d-peak map, spectra, g-peak map, 2d-peak map)

References

1) Comparative study of single and multi domain CVD graphene using large-area Raman mapping and electrical transport characterization Kishan Thodkar, Maria El Abbassi, Felix Lüönd, Frédéric Overney, Christian Schoenenberger, Blaise Jeanneret, and Michel Calame. physica status solidi (RRL) – Rapid Research Letters, 10(11), 807-811, 2016

2) Restoring the electrical properties of CVD graphene via physisorption of molecular adsorbates  Kishan Thodkar, Damien Thompson, Felix Lüönd, Lucas Moser, Frédéric Overney, Laurent Marot, Christian Schönenberger, Blaise Jeanneret, and Michel Calame.  ACS Applied Materials & Interfaces, 2017

3) Chemical vapor deposited graphene for quantum Hall resistance standards Kishan Thodkar, phD Thesis

4) Robust graphene-based molecular devices El Abbassi M., Sangtarash S., Liu X., Perrin M.-L., Braun O., Lambert C., van der Zant H., Yitzchaik S., Decurtins S., Liu S., Sadeghi H. & Calame M., Nature Nanotechnology (2019)

5) Optimized Graphene Electrodes for contacting Graphene Nanoribbons, Braun O, Overbeck J, El Abbassi M, Käser S, Furrer R, Olziersky A, Flasby A, Borin Barin G, Sun Q, Darawish R, Müllen K, Ruffieux P, Fasel R, Shorubalko I, Perrin ML & Calame M, Carbon, 184, 331-339. (2021)

 

Transport at Nanoscale Interfaces Laboratory

Contact us

 

Roman Furrer
Dipl. Ing. FH

Phone: +41 58 765 4098