Atomic-layer-deposited nanostructures for graphene-based nanoelectronics

作者：Yi Xuan, Yanqing Wu, Tian Shen, Minghao Qi, M. A. Capano, James A. Cooper, P. D. Ye · 发表于：Applied Physics Letters · 年份：2008 · DOI：10.1063/1.2828338 · 被引用次数：225 · 研究领域：Graphene research and applications、Semiconductor materials and devices、Ferroelectric and Negative Capacitance Devices

Graphene is a hexagonally bonded sheet of carbon atoms that exhibits superior transport properties with a velocity of 108cm∕s and a room-temperature mobility of >15000cm2∕Vs. How to grow gate dielectrics on graphene with low defect states is a challenge for graphene-based nanoelectronics. Here, we present the growth behavior of Al2O3 and HfO2 films on highly ordered pyrolytic graphite (HOPG) by atomic layer deposition (ALD). To our surprise, large numbers of Al2O3 and HfO2 nanoribbons, with dimensions of 5–200nm in width and >50μm in length, are observed on HOPG surfaces at growth temperature between 200 and 250°C. This is due to the large numbers of step edges of graphene on HOPG surfaces, which serve as nucleation sites for the ALD process. These Al2O3 and HfO2 nanoribbons can be used as hard masks to generate graphene nanoribbons or as top-gate dielectrics for graphene devices. This methodology could be extended to synthesize insulating, semiconducting, and metallic nanostructures and their combinations.