
US Patent No: 7,336,441
Number of patents in Portfolio can not be more than 2000
Yoke structure with a step
Stats
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Feb 26, 2008
Issued date -
Jul 26, 2006
filing date -
11/493,775
serial no -
In Force
status
Importance
Abstract
A planar top yoke in a magnetic write head is disclosed. The top yoke includes a backside region and a second pole tip region that is thinner than the backside region and forms a step at the ABS. Alternatively, a front section of the backside region includes a step with a thickness greater than the second pole tip region. Therefore, flux is directed from a thicker backside region toward the gap side of the second pole tip layer near the ABS. A lower flux density is formed at the top of the step at the ABS which reduces the flank field/gap field ratio and prevents unwanted erasure of adjacent data tracks. A high gap field is achieved while maintaining a low flank field during high write current conditions. The step recess from the ABS toward the backside region is about 0.2 to 2 microns.
First Claim
Related Publications
International Classification(s)
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- [Patents Count]
Cited Art
| Patent Info | (Count) | # Cites | Year |
|---|---|---|---|
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| 6,029,339 Method of making write head with recessed stitched yoke on a planar portion of an insulation layer defining zero throat height | 21 | 1998 | |
| 6,111,724 Method of making a magnetic write head with plated self-aligned zero throat height defining layer without reflective notching of a second pole tip | 48 | 1998 | |
| 6,337,783 Write head with multi-stitched second pole piece | 29 | 1998 | |
| 6,473,276 Merged magnetic head which includes a write head with single-sided notched first pole piece | 6 | 2000 | |
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| 6,504,675 Perpendicular magnetic recording heads with write pole shaped to reduce skew effects during writing | 127 | 2001 | |
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| 6,668,442 Method of manufacturing a thin film magnetic head | 11 | 2001 | |
Patent Citation Ranking
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