Method of making thin film induction recording head having an inset first insulation layer that defines zero throat height and pole tip apex angle
US5935644A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 4, 1998 |
| Grant date | Aug 10, 1999 |
| Priority date | — |
| Expiry date | Mar 4, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/232
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention uncouples the dependence between the zero throat height and the flare point of a write head by recessing the first insulation layer within the first pole piece layer. The first pole piece layer and the first insulation layer have planar surfaces which preferably lie in a common plane, the zero throat height being defined at the point where the planar surface of the first pole piece layer first meets the planar surface of the first insulation layer within the head. It is also at this point that the first and second pole piece layers separate from one another. Accordingly, the zero throat height can be accurately placed relative to the stripe height of a magneto-resistive (MR) sensor. Further, when a photoresist layer is spun onto the partially completed head for the construction of the pole tip of the second pole piece light directed into the photoresist layer for photo-imaging the pole tip does not reflect into the photoresist layer adjacent the pole tip. Accordingly, there is substantially no reflective notching of the photoresist layer because of the flatness of the surfaces of the first pole piece layer and the first insulation layer thereby permitting cons…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.