Microsystem Technologies

, Volume 16, Issue 6, pp 1021–1034 | Cite as

Optimization of thermal fly-height control slider geometry for Tbit/in2 recording

  • Antonis I. Vakis
  • Andreas A. Polycarpou
Technical Paper


Magnetic storage advances including thermal fly-height control (TFC) technology were able to reduce the clearance between the read/write elements of the slider and the disk surface to increase the recording density of hard disk drives without compromising the stability of the head–disk interface (HDI). Sliders employing TFC technology are designed for flying recording and can yield clearances of few nanometers. However, it is estimated that TFC technology alone cannot provide the even smaller clearances necessary to achieve Tbit/in2 recording densities primarily due to the presence of instability-inducing vibrations at the HDI. In this work we perform optimization of the geometry of TFC technology sliders to achieve extremely high-density recording. We propose a flyability parameter coupled with a dynamic, contact mechanics-based friction model of the HDI that accounts for TFC geometry and its influence on the HDI dynamics. Optimization results are analyzed and an operating actuation range is identified that can yield Tbit/in2 recording densities with Angstrom-level clearance and minimized vibrations while also accounting for manufacturing and operational tolerances. This allows for light (lubricant) contact or ‘surfing’ recording. The proposed methodology can be used to reduce wear at the interface and investigate the feasibility of contact recoding.


Lubricant Layer Solid Contact Nominal Area Trail Edge Topographical Roughness 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The authors would like to acknowledge the support of the Information Storage Industry Consortium’s Extremely High Density Recording program and Melih Eriten, Microtribodynamics Laboratory, University of Illinois at Urbana-Champaign, for his help on optimization methods.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  1. 1.Department of Mechanical Science and EngineeringUniversity of Illinois at Urbana-ChampaignUrbanaUSA

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