▎ 摘　　要

When a graphene sheet is transferred onto a Si-terminated SiC(0001) substrate, covalent Si C bonds form at the interface. These interfacial bonds may form domains with a regular lattice pattern. The domain size is dictated by the lattice mismatch between graphene and its substrate. In the present work, a strategy of strain engineering is employed to eliminate the lattice mismatch to achieve a perfect epitaxy between the graphene and the substrate. Both molecular mechanics simulations and density function calculations confirm the perfect epitaxial pattern formed between a prestrained graphene sheet and its underlying silicon-carbide substrate. We further examine the edge effect on the disruption of the epitaxial pattern of prestrained graphene nanoribbons. It is found that that the perfect epitaxial pattern is disrupted only along the narrow regions near the nanoribbon edges, and the size of the affected region of the arm-chair ribbon is about 3 times larger than that of the zigzag ribbon.