Abstract
Two types of alumina nanostructure, ′nanoball′ and ′nanowire′, were obtained from the delta alumina particles by the electron beam irradiation in TEM. Irradiation intensity was 2.0 x 1021 e/cm2sec, a few thousands times higher than normal operating condition. Nanoballs having about 10nm in diameter might consist of delta alumina structure which was induced by the sputtering effect of electron beam, whereas nanowires having 100nm in length and 10nm in diameter grew by electron irradiation. Some of nanoballs adhered to the nanowire. These alumina nanostructures differ from aluminum nanodecahedron obtained by the same electron beam irradiation to theta alumina particles reported by B.-S. Xu and S.-I. Tanaka in 1997. The nanoballs also moved toward the irradiation center with five times higher speed than that Xu and Tanaka reported.
