Publication: Direct observation of grain boundaries in graphene through vapor hydrofluoric acid (VHF) exposure

  three raman spectroscopy images Copyright: © Stefan Wagner

This method for evaluating atomic-scale defects in graphene could help boost large scale production of ‘wonder’ conductor. The work conducted was a collaboration between the Royal Institute of Technology (KTH) Stockholm , RWTH Aachen University, Chemnitz University of Technology and AMO GmbH. It has recently been published in Science Advances.

The RWTH Aachen University researchers and their colleagues found an experimental method to proper visualization the graphene grain boundaries. The study provides a method to simply, quickly and cost-effectively observe the size and distribution of grain boundaries on a large scale by using standard processes in wafer fabs, namely, vapor hydrofluoric acid (VHF) etching and optical microscope inspection. Up to now, no method exists that compares in simplicity, speed and scale to this methodology for visualizing grain boundaries in large-area CVD graphene on a silicon dioxide (SiO2) substrate. Scientists could make big gains in controlled engineering of these unavoidable defects.

The research was funded by the European Research Council through the Starting Grants M&M’s (277879) and InteGraDe (307311), the Swedish Research Council (GEMS, 2015-05112), the China Scholarship Council (CSC), the German Federal Ministry for Education and Research (NanoGraM, BMBF, 03XP0006C),the German Research Foundation (DFG, LE 2440/1-2) and the German Research Council (DFG) through the Priority Program SPP 1459 Graphene.