Patent ID: 8778197

Claim:
A method comprising: a. selecting a metal foil having a first face and a second face, wherein the metal foil comprises at least 99.8% by weight of metal; b. growing a first layer of graphene on the first face of the metal foil to form a graphene-modified foil, wherein the second face of the graphene-modified foil is selected from the group consisting of i. a second layer of graphene on the second face of the metal foil, wherein the second layer of graphene was grown during the step of growing the first layer of graphene, and ii. the second face of the metal foil; c. patterning the second face of the graphene-modified foil with a polymer, wherein the second face of the graphene-modified foil has an exposed region; d. etching the second face of the graphene-modified foil in the exposed region until exposing the first layer of graphene, wherein a graphene window is formed.