Novel profiling model and side effects of helical scan silicon heads

Abstract

Partial erasure of track edges was directly measured from triple-track patterns using a novel model to interpret the output profiles. The model is based on representing the read head as the sum of a reference width, wavelength independent, and two side reading effective widths that are wavelength dependent. We applied this technique to measure erase bands and side read widths of an advanced helical scan silicon head with 3.5-m pole width, in combination with metal particle tape with coercivity = 135 kA/m. The good pole alignment of the head minimizes side effects and we report an erase band of 0.3 m for a 0.5-m wavelength track overwriting the edge of a track having the same wavelength.

Recording Performances of Perfectly Aligned HSS Heads

“…The difference between the widths of the center microtracks was deduced from the values of their erase offsets to be 0. 5 . We could thus estimate that the effective track width reduction at each edge is less than 0.5 up to a wavelength of 0.2 .…”

“…It is therefore expected that the MIG head generates larger erase bands than the HSS head. The erase bands of the HSS and MIG heads were deduced from triple-track patterns using the interpretation technique described in [5]. A central track with wavelength was used to overwrite with partial overlap two side tracks of wavelength .…”

“…However, most improvements are expected from the write heads that should generate better-confined fields, using well-aligned magnetic poles and short gap length. The Helical Scan Silicon (HSS) heads are an innovative step toward these features [4], [5]. In this work, the recording performances of HSS heads with very good pole alignment were investigated, with great emphasis on their edge effects.…”