AVS 46th International Symposium
    Vacuum Metallurgy Division Tuesday Sessions
       Session VM+MI+AS-TuA

Paper VM+MI+AS-TuA8
Angle Resolved ESCA Methods: Molecular Conformation of Fluorocarbon Lubricant

Tuesday, October 26, 1999, 4:20 pm, Room 620

Session: Magnetic Recording: Head/Disk Interface and Overcoats
Presenter: M.A. Karplus, IBM-SSD
Authors: M.A. Karplus, IBM-SSD
D.J. Pocker, IBM-SSD
Correspondent: Click to Email
Simple but useful methods for interpreting angle-resolved ESCA data from real-world samples are presented. First is a model allowing thinly-covered and thickly-covered substrate. It can be usefully applied, even in a manual fashion, with common office spreadsheets. Next, a simple slab model, with the help of canned minimization routines, can bring out subtleties in overlayer structures. Even a deeply buried monatomic layer can be isolated. The following are presented as examples. Perfluoropolyether (Zdol) lubricant on hard disk carbon overcoat shows coexisting monolayer and multilayer regions, consistent with structures identified by surface energy@footnote 1@ and ellipsometric surface diffusion@footnote 2@ measurements. Next, layering within the lubricant shows significant perfluoropolyether backbone adjacent to the overcoat surface accompanied by a discernible excess of ether oxygen. The latter facts indicate that the inverted-U conformation sometimes sketched for bonded lubricants is an exaggeration, certainly for the system studied. @FootnoteText@ @footnote 1@ G. W. Tyndall, R. J. Waltman, and D. J. Pocker, Langmuir 14, 7527 (1998). @footnote 2@ X. Ma, J. Gui, L. Smoliar, K. Grannen, B. Marchon, M. S. Jhon, C. L. Bauer, J. Chem. Phys. 110, 3129 (1999).