Font Size: a A A

Template-Based Fabrication of Nano Structured Material and Its Electronic Application

Posted on:2011-05-10Degree:Ph.DType:Dissertation
University:University of California, Los AngelesCandidate:Sun, KeFull Text:PDF
GTID:1441390002455965Subject:Engineering
Abstract/Summary:
In the field of nano fabrication, top down and bottom up approaches are two fabrication strategies representing the trade-off between resolution and controllability. In this dissertation, a novel template-based fabrication technique is presented combining the advantages of both top down and bottom up approaches: nanostructured material can be synthesized and tailored at true nanometer scale to suit the purpose of different studies.;Self-assembly PS-PMMA di-block copolymer patterning and well controlled anisotropic dry/wet etching are used to create a generic template with nanosized pits in inverted-pyramidal shape with atomically sharp apex. This unique geometry can be taken advantage to fabricate various nanostructures. In this work it is applied in two studies including nano volume phase change material and atomically sharp field emitters.;To explore the ultimate scaling projections of the emerging phase change memory technology, sub-10 nm nanoclusters of phase change material have been achieved by template-based fabrication. Various characterization techniques are adopted to study the morphology, crystallinity, stoichiometry and the phase transforamtion behavior of the nano volume phase change material. Degraded phase stability and reduction in amphorization temperature compared with bulk case is observed, suggesting scaling concerns for future technology node of phase change memory.;Atomically sharp tungsten emitter array is also synthesized by template-based fabrication using a nanocasting method. The template with nanopits is used as a casting mold to create field emission tungsten nanotips, which exhibit atomic sharpness, high emitter density and perfect alignment. Excellent field emission properties have been demonstrated with low turn-on field, high field enhancement factor and good emission stability. Capability of room-ambient field emission has also been demonstrated with a nanometer anode-cathode spacing that is uniquely allowed by the small height fluctuation of the tungsten nanotips.
Keywords/Search Tags:Nano, Fabrication, Material, Field, Phase change
Related items