Diffuse interface electron scattering in epitaxial Co/Cu bilayers

David J. Keavney, Sungkyun Park, Charles M Falco

Research output: Contribution to journalArticle

7 Scopus citations

Abstract

We have examined the origin of diffuse electron scattering at Co/Cu interfaces using in situ resistance measurements and scanning tunneling microscopy (STM) on a model system consisting of epitaxial (111)-oriented Co on Cu and Cu on Co. We grew epitaxial Co/Cu bilayers on 40 Å Cu(111)/Si(111) substrates, and monitored the resistance and surface morphology during the initial stages of growth for both Co on Cu and Cu on Co. For the case of Co on Cu, the resistance initially increases by 10% at submonolayer coverage, and then drops after 1-1.5 ML coverage. In situ STM topographs taken at similar stages of growth reveal that 20-30 Å Co islands initially nucleate above Cu step edges at submonolayer coverage and then grow inward to cover the Cu terraces. These islands introduce new steps at the surface, dramatically reduce the lateral correlation length of the surface profile, and consequently increase its contribution to the surface scattering resistance. We find that the nucleation and percolation of these islands is strongly correlated with the resistance behavior. In contrast, for Cu deposited on Co, we observe no island nucleation, and no corresponding resistance increase.

Original languageEnglish (US)
Pages (from-to)8108-8110
Number of pages3
JournalJournal of Applied Physics
Volume91
Issue number10 I
DOIs
Publication statusPublished - May 15 2002

    Fingerprint

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this