Hydrogen etch resistance of aluminium oxide passivated graphitic layers

Graphene inherently possesses defect sites and grain boundaries which are vulnerable to chemical etching by hydrogen radicals. In this research, an etch mitigation method is presented to passivate these sites selectively using atomic layer deposition (ALD) of a H etch resistant material. First, pristine exfoliated graphitic layers are exposed to H radicals to determine the lateral etch rate from defect sites as a reference experiment. Next these samples are compared to graphitic layers in which the defects are selectively deposited by Al2O3, in the same exposure conditions, using atomic force microscopy (AFM) at every step in the experiment. The results show that etching is slowed down by local deposition of Al2O3 ALD at sites vulnerable for H radical etching.