Hydrogen etch resistance of aluminium oxide passivated graphitic layers

Abstract

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

Role of O2 and N2 addition on low-reflectance Si surface formation using moderate-pressure (3.3 kPa) hydrogen plasma

“…By contrast, in our plasma, the increase in I H did not rely solely on the suppression of Si etching by covering the surface with Si oxide. To suppress the effect of the solid surface as far as possible, H 2 plasma was generated on a 1 mm-thick sintered alumina substrate, which hardly interacted with H 2 plasma or absorbed H atoms [29,30]. Using this experimental arrangement, the dependence of I H on the O 2 and N 2 additives was investigated.…”