SPIN ELECTRONICS: Varied Synthetic Approaches to the Development of Room-Temperature Ferromagnetic and Semiconducting Oxide Nanostructures for Silicon Based Spintronics

University Of Washington, Seattle WA

Investigators

Abstract

This proposal was received in response to the Spin Electronics for the 21st century Initiative, Program Solicitation NSF 02-036. The proposal focuses on the synthesis, characterization and optimization of Cobalt-doped transition metal oxide nanostructures for spin-electronics applications. The proposed work is based on our recent demonstration of robust ferromagnetic and semiconducting behavior at room temperature in Co-doped anatase thin films. The proposed research will establish interrelationships among the structural, optical, electronic, and magnetic properties of ferromagnetic, semiconducting CoxTi-1-x02 fabricated by a variety of physical and chemical synthesis routes, including oxygen plasma assisted molecular beam epitaxy, reactive ion-beam sputter deposition, and solution-based hydrothermal, sol-gel, and aqueous co-precipitation methods. Different synthetic routes should lead to different morphologies and dimensionalities, including single-crystal films (2D), nanoparticles (OD), and planar arrays of nanostructures. They also have different prognoses and costs for scaling from laboratory to commercial operation. Spin-dependent transport and magnetic behavior of these materials as a function of dimensionality and structure will be investigated. Detailed evaluation of the band structure of the films, combined with proprietary technology involving SrTiO3 buffer layers, will be used to integrate these films on silicon substrates. The ultimate goal will not only be to engineer these materials at the nanometer length scales, but to develop a broad set of criteria that will serve as the framework to explore the viability of other doped-oxides for spintronics applications. Finally, the project has a broad education component that will add new dimensions to the research experience and training of graduate students participating in the nanotechnology IGERT program on the UW campus. This proposal is being co-funded by the Divisions of Civil and Mechanical Systems, Chemical and Transport Systems and Electrical and Communication Systems in the Directorate of Engineering of the National Science Foundation.