Metal silicide nanowires

Abstract

Nanotechnology is a new paradigm and not just a research trend, as it can be applied to all existing fields of science and technology. All materials ever developed can potentially be synthesized in nanoform through current synthetic technology. Interestingly, nanomaterials sometimes show fascinating properties that have never before been observed in bulk. In particular, among the various nanostructures in existence, nanowire is considered a promising candidate as a building block for nanoelectronics because of its high aspect ratio, which allows for electromagnetic transport. Currently, nanotechnology consists of three parts: synthesis of nanomaterials, fabrication of nanodevices using nanomaterials, and future technology applications. However, even in each of these three fields, the synthesis of nanomaterials is essential because each application needs appropriate materials that have specific shapes and properties. To date, the majority of nanostructure synthesis has been with semiconductors, and as a result, current nanotechnology has been focused on semiconductor industry. If we can develop new nanomaterials that display novel metallic, semi-metallic, or superconducting properties, it would further expand the applicability of nanotechnology. Metal silicides are one of the best candidates for a potentially new class of nanomaterials because of the variety of electrical, mechanical, and magnetic properties they possess. This dissertation presents the synthesis, structural characterization, and physical properties of various metal silicide nanowires, which in this work are further distinguished as thermodynamically stable phase, metastable phase, and ternary system nanowires. First, thermodynamically stable metal silicide nanowires such as CoSi, FeSi, and $CrSi_2$ were synthesized on a Si substrate via a halide vapor transport method. Because inter-diffusion of elements is the rate determining step in solid state reactions between two el...