Thin-film magnetic head with gap and pole portion layers having cross sections of the same shapes and predetermined parameter ranges
US7248435B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 20, 2004 |
| Grant date | Jul 24, 2007 |
| Priority date | — |
| Expiry date | Jul 7, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/3906
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A bottom pole layer and a top pole layer respectively incorporate pole portion layers. Cross sections of the pole portion layers and a gap layer parallel to the top surface of a substrate are of the same shapes. The aggregate of the pole portion layers and the gap layer includes a first portion having a width W that defines the track width, and a second portion having a width greater than the width W of the first portion. L/W falls within a range of 2 to 5 inclusive, where L is the distance from a medium facing surface to the interface between the first portion and the second portion. S/(W×L) falls within a range of 5 to 40 inclusive, where S is the area of the cross section of the aggregate parallel to the top surface of the substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.