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Author Boyanov, B. I. ♦ Goeller, P. T. ♦ Sayers, D. E. ♦ Nemanich, R. J.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword MATERIALS SCIENCE ♦ COBALT COMPOUNDS ♦ COBALT SILICIDES ♦ EPITAXY ♦ GERMANIUM SILICIDES ♦ INTERFACES ♦ CHEMICAL REACTIONS ♦ SURFACE ENERGY ♦ THIN FILMS ♦ ANNEALING
Abstract A technique for achieving epitaxial growth of (001)-oriented CoSi{sub 2} on strained epitaxial layers of Si{sub 1{minus}x}Ge{sub x}(001) is described. The technique is based on a variation of the template method, and is designed to control the local environment of Co atoms at the CoSi{sub 2}/SiGe interface. The effects of the Co{endash}Ge interactions on the interfacial reaction and the epitaxial orientation and the morphology of the silicide film were investigated. This reaction was found to cause pitting in (001)-oriented CoSi{sub 2} films, and to stabilize the (22{ovr 1}) orientation for films codeposited under conditions where CoSi{sub 2}(001) growth is achieved on Si(001) substrates. The (22{ovr 1})-oriented CoSi{sub 2} films were islanded after annealing at 700thinsp{degree}C. The islands were terminated by ({ovr 1}11) and (110) facets inclined at 15.8{degree} and 19.5{degree}, respectively, from CoSi{sub 2} [22{ovr 1}] towards CoSi{sub 2} [114]. These results were interpreted in terms of reduction of interfacial and surface energies, and geometric effects. Silicide films up to 730-{Angstrom}-thick were deposited and annealed up to 900thinsp{degree}C. The films were stable against agglomeration, and retained tensile stress in the CoSi{sub 2} layer after annealing at 700thinsp{degree}C. The rms roughness of the CoSi{sub 2} films was comparable to that of the Si(001) substrate{emdash}less than 15 {Angstrom} over areas as large as 20{times}20 {mu}m{sup 2}. Films annealed at 900{degree}C were severely agglomerated. {copyright} {ital 1999 American Institute of Physics.}
ISSN 00218979
Educational Use Research
Learning Resource Type Article
Publisher Date 1999-08-01
Publisher Place United States
Journal Journal of Applied Physics
Volume Number 86
Issue Number 3


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