Accession Number : ADA329169

Title :   Investigations of the Epitaxial Growth and Characterization of High Perfection Magnetic Thin Films.

Descriptive Note : Final rept. Oct 86-Oct 91,

Corporate Author : IBM ALMADEN RESEARCH CENTER SAN JOSE CA

Personal Author(s) : Farrow, R. F. ; Parkin, S. S.

PDF Url : ADA329169

Report Date : 1991

Pagination or Media Count : 43

Abstract : Methods of preparing high-perfection single crystalline films of 3d elements (including Fe, Co) and magnetic rare earths on semiconducting GaAs substrates have been investigated. The use of seed layers of Fe or Co (a few monolayers thick), deposited onto GaAs(001), followed by a Ag(001) film, provided a suitable template for Fe epitaxy. This method avoided interfacial chemical reactions between Fe and the semiconductor, at the expense of introducing coherency strain and tilted epitaxy of the Fe. In the case of rare earths, intermediate seed films of rare earth trifluorides, grown onto GaAs(111(-)) provided a template for growth of c-axis oriented rare earth films and sandwich structures. These methods have enabled the effects of coherency strain on magnetic properties of Fe and rare earths to be investigated. Using an automated X-ray photoelectron diffraction (XPD) system we have investigated the growth and interfacial mixing of several key epitaxial systems including Co/Pt, Co/Ag, NdF3/LaF3 and Pt/GaAs. Interfacial mixing in the interfaces of Co/Pt superlattices was confirmed, resulting in an alloyed region containing the ordered L12 phase: CoPt3. Spin-polarized photoelectron diffraction (SPPD) experiments on MnF2 suggest a new , high-temperature magnetic ordering transition at 380K which is 313K above the Neel temperature.

Descriptors :   *GALLIUM ARSENIDES, *THIN FILMS, *EPITAXIAL GROWTH, AUTOMATION, SUPERLATTICES, X RAY DIFFRACTION, SUBSTRATES, STRAIN(MECHANICS), SEMICONDUCTORS, IRON, X RAY PHOTOELECTRON SPECTROSCOPY, DOPING, RARE EARTH ELEMENTS, MAGNETIC MATERIALS, SANDWICH CONSTRUCTION, NEEL TEMPERATURE.

Subject Categories : Crystallography
      Solid State Physics
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE