Paper AS-TuP21
Analysis of DLC Fine Structure on Sliders by Using Second Derivative Carbon KLL Auger Spectra

Tuesday, October 21, 2008, 6:30 pm, Room Hall D

Present hard disc drive (HDD) manufacturing technology uses diamond-like carbon films (DLC) as overcoats for both head and media. These DLC films function to protect underlying magnetic metals from wear and corrosion both during the manufacturing process and throughout the design lifetime of the drive. Recording head DLC film thickness can vary from ~15 to ~30 Å while typical values of DLC films for magnetic media are in excess of 30 Å. Auger analysis is particularly suitable for overcoat studies due to the surface sensitivity of the technique. In this study an Omicron high resolution Auger/SEM system was utilized to investigate the DLC at the head air bearing surface. Carbon’s Auger spectrum is particularly sensitive to the type of bond hybridization.¹ Graphite, diamond, and silicon carbide have distinctive Auger CKLL spectra and its fine structure that can be used to identify the form of carbon at the surface. A second derivative of the Auger spectrum was utilized to remove the background and highlight the carbon fine structure peak locations (maximum negative curvature).² To remove the surface hydrocarbons a 15 second 0.3keV Ar etch was utilized. W. Zhu et. al. showed that by reducing the Ar beam energy to 0.3keV and limiting the total flux to 1.0 x 10¹⁴ ions/cm² an effective cleaning of hydrocarbon contaminates from the surface of CVD diamond films was accomplished without negatively impacting the diamond carbon bond structures.³ In-situ XPS data on DLC grown films on coupons was also completed for comparison of the carbon bond structure.

¹T.W. Haas, J.T. Grant, and G.J. Dooley III, J. Appl. Phys., 43, (1972) 1853.
²Lascovich and A. Santoni, App. Surf. Sci., 103, (1998) 245.
³W.Zhu, J.E. deVries, M.A. Tamor, K.Y. Simon Ng, Surface Coatings Technology, 71, (1995) 37.