The electrically operated phase-change random access memory (PRAM) features faster write/read, improved endurance, and much simpler fabrication as compared with the traditional transistor-based nonvolatile semiconductor memories. Low-dimensional phase-change materials in nanoscale dimensions offer advantages over their bulk or thin-film counterpart in several aspects such as reduced programmable volume and reduced thermal energies in phase transition. These features contribute to low power operation, excellent scalability, and fast write/erase time. In this paper we reported a general bottom-up synthesis approach and systematic material analysis study of one-dimensional chalcogenide-based phase-change materials, germanium telluride (GeTe) and germanium antimony telluride (Ge2Sb2Te5) nanowires, which are targeted for nonvolatile resistive switching data storage. The phase-change nanowires have been synthesized via thermal evaporation method under vapor-liquid-solid (VLS) mechanism. The physical morphology, chemical composition, and crystal structure of the synthesized nanowires were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HR-TEM) and X-ray photoemission spectroscopy (XPS). The as-synthesized nanowires are structurally uniform with single crystalline structures. The 1-D phase-change chalcogenide nanowires exhibit significantly reduced melting points, low activation energy and excellent morphology, making them promising nanomaterials for data storage devices with very low energy consumption and excellent scalability.
Journal: TechConnect Briefs
Volume: 1, Technical Proceedings of the 2007 NSTI Nanotechnology Conference and Trade Show, Volume 1
Published: May 20, 2007
Pages: 233 - 236
Industry sector: Advanced Materials & Manufacturing
Topicss: Advanced Materials for Engineering Applications, Nanoparticle Synthesis & Applications