Self-organization of large-area periodic nanowire arrays by glancing incidence ion bombardment of CaF2(111) surfaces

The fabrication of well-ordered nanowire arrays over large areas is a chall enge with many potential applications. Here we report a novel glancing inci dence ion beam assisted self-organization approach to form periodic wire ar rays over large areas on a CaF2(111) substrate. Preferential erosion of flu orine by the 4.5 keV Ar+ ion beam creates a surface enriched in calcium. Th e calcium self-organizes in elongated island structures of preferential wid th and separation. If the sample is irradiated along a fixed azimuth we obs erve nanowires with similar to 10 nm periodicity and wire lengths of at lea st several micrometers oriented along the azimuthal direction of ion beam i ncidence. Electrical conductivity measurements reveal an anisotropy in cond uctivity of at least three orders of magnitude. (C) 2001 American Vacuum So ciety.