Diameter-controlled Growth of GeTe Phase-change Nanowires via a Au Catalyst-assisted Vapor–liquid–solid Mechanism

Abstract

Growth of diameter-controlled GeTe phase-change nanowires (NWs) on Si substrates is demonstrated by a Au catalyst-assisted chemical vapor deposition (CVD) technique. Besides Au catalyst size, GeTe source powder amount, an uncommon growth parameter, is also employed to control the diameter of GeTe NWs. The diameter of GeTe NWs shows an obvious increase with the increase of both Au catalyst size and GeTe powder amount. By effectively controlling the Au nanoparticle size and GeTe powder amount, the diameters of GeTe NWs can be tunable in a wide range of 150 to 280 nm. The effects of the Au nanoparticle size and GeTe powder amount on the diameter of GeTe NWs are revealed in terms of supersaturation detailedly based on the Gibbs–Thomson effect.