Metal silicide and germanide 1D nanostructures: synthesis, characterization, and applications

Abstract

There are a great number of opportunities for various applications by fabricating new types of nanostructures, or simply by down-sizing existing microstructures into the nanoscale. In particular, among the various nanostructures in existence, one dimensional (1D) nanostructures, such as nanowires (NWs), nanobelts, and nanotubes (NTs), have unique electronic, optical, and mechanical properties as a result of their dimensional anisotropy and the quantum confinement effect. Metal silicides and germanides are among the best candidates for a potentially new class of nanomaterials because they have diverse electrical and magnetic properties as well as they are compatible with existing complementary metal-oxide-semiconductor (CMOS) technologies. Thus, metal silicide and germanide 1D nanostructures can be very usefully employed to build future nanoelectronic and nanospintronic devices. In this dissertation, we present the synthesis, characterization, and applications of various metal silicide and germanide NWs. First, synthetic approaches and applications of various metal silicide and germanide 1D nanostructures have been reviewed. Second, we report the synthesis of MnSi NWs and measurements of their electrical and magnetic properties. Third, synthesis and morphology control of Co5Ge7 1D nanostructures are investigated. Field emission (FE) properties of vertical Co5Ge7 NW arrays are also reported. Fourth, we report the results of both experimental and theoretical studies on the ferromagnetic stabilization of freestanding hexagonal Fe1.3Ge NWs and their origin. Fifth, vertical growth of Fe1.3Ge NW arrays on few-layer graphene and their FE properties are studied. Finally, self-aligned growth of in-plane and out-of-plane monoclinic CoGe NWs and their electrical properties are investigated. The abstracts for each chapter are as follows.