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Barrier-guided CVD growth could provide a new route to printed electronics by combining high quality 2D materials synthesis with scalable and cost-effective deposition methods. Unfortunately, we observe the limited stability of the barrier at growth conditions which results in its removal within minutes due to hydrogen etching. This work describes a route towards enhancing the stability of an ink-jet deposited barrier for high resolution patterning of high quality graphene. By modifying the etching kinetics under confinement, the barrier film could be stabilized and high resolution barriers could be retained even after 6 hours of graphene growth. Thus produced microscopic graphene devices exhibited an increase in conductivity by 6 orders of magnitude and a decrease in defectiveness by 48 times yielding performances that are superior to devices produced by traditional lithographical patterning which indicates the potential of our approach for future electronic applications.

The quality of CVD-grown graphene is intimately linked to the morphology of the employed catalyst. One commonly employed route to enhanced catalyst quality is recrystallization prior to graphene growth. The dimensions of a catalyst's single-crystalline domains, however, are limited by the stability of dislocations at the grain boundaries. We here employ a solid material in contact with the catalyst as a sink for dislocations. It was found that the interaction between Cu-foil and a solid cap significantly alters the recrystallization kinetics and achievable grain size. This development originates from an improved strain-relaxation of up to 1% during recrystallization which can support the formation of commonly unstable surface orientations. Correlation of diffraction measurements and atomic force microscopy reveals a direct impact of the strain relaxation on the decrease in copper surface roughness. Finally, we demonstrate the improvement of the quality of graphene grown on thus prepared foils through spectroscopic and carrier transport measurements.