Effect of a Balanced Concentration of Hydrogen on Graphene CVD Growth

Figure 5

The flows of methane and hydrogen are demonstrated as a function of the growth time. Methane flow is stable. Hydrogen flow is stable for sample B. In sample C a 2-step recipe is followed. In the second step the hydrogen flow is stopped. This moderates the hydrogen etching effect, resulting in increase of the graphene surface coverage from 25% to 99% of the total surface.