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

Paper VM+MI+AS-TuA2
Tribological Properties of Protective Carbon Coatings Used in Magnetic Storage Devices Investigated on a Sub-Nanometer Scale

Tuesday, October 26, 1999, 2:20 pm, Room 620

Session: Magnetic Recording: Head/Disk Interface and Overcoats
Presenter: A. Wienss, University of Saarbrücken, Germany
Authors: A. Wienss, University of Saarbrücken, Germany
G. Persch-Schuy, IBM Germany Storage Systems Division
U. Hartmann, University of Saarbrücken, Germany
Correspondent: Click to Email
Ultrathin carbon coatings are used in the magnetic storage industry to protect sensitive sensor heads and magnetic media against mechanical damage. Such a damage can be modelled by artificially generated scratches using Scanning Force Microscope (SFM) techniques. Loading forces in the µN range are applied, resulting in scratches with residual depths of only a few Å. A special image subtraction technique is presented which allows careful analysis of tiny grooves even on rough surfaces. This technique compensates for drift effects during scanning. The scratching resistance of various a-C:H and CN@sub x@ films is determined. For a-C:H, an increasing amount of hydrogen results in a decreasing scratching resistance, which is a well-known behavior. Beyond a certain hydrogen content, a further increased hydrogenation causes a reproducible, slight increase of the scratching resistance. In order to explain this, the role of the friction coefficient will be discussed.