D. Gonzalez et al., The dynamic coupling of the slider to the disk surface and its relevance to take-off height, IEEE MAGNET, 37(4), 2001, pp. 1839-1841
Recent studies have attempted to correlate take-off height (TOH or Glide Av
alanche) of rigid disks to their topography. Roughness average, mean peak h
eight, and waviness have been emphasized, but no model has been proposed th
at takes into account the dynamic response of the glide slider to the spati
al frequency of the disk topography. In this paper, we calculate the freque
ncy response of glide sliders to disk inputs of various wavelengths, using
an air-bearing solver. This calculated trans er unction is then used to fil
ter the one-dimensional disk topography, obtained with a conventional stylu
s profiler, using its complex Fourier transform. From the filtered profile,
a mean peak height R-pm can be obtained which correlates well with actual
TOH values. The slope is close to unity as expected from a first-principle
model. Schemes to break down the wavelength range of interest into short (r
oughness) and long (waviness) parts will be demonstrated, as well as the pr
actical use of optical profilers.