Etching and narrowing of graphene from the edges

摘要: Large-scale graphene electronics requires lithographic patterning of narrow nanoribbons for device integration. However, conventional lithography can only reliably pattern approximately 20-nm-wide GNR arrays limited by resolution, while sub-5-nm GNRs are desirable high on/off ratio field-effect transistors at room temperature. Here, we devised a gas phase chemical approach to etch from the edges without damaging its basal plane. The reaction involved temperature oxidation in slightly reducing environment presence ammonia afford controlled rate (less than or 1 nm min(-1)). We fabricated 20-30-nm-wide nanoribbon lithographically, and used etching chemistry ribbons down <10 nm. For first time, up 10(4) was achieved built with sub-5-nm-wide semiconductors derived narrowing. Our method opens way control size various nano-structures beyond capability top-down lithography.