Method for making a thin film magnetic head
US4861398A · kind A · utility
18Cited by
7References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 20, 1987 |
| Grant date | Aug 29, 1989 |
| Priority date | — |
| Expiry date | Nov 20, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49046
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
DC bias currents are applied to a conducting wire of a thin film magnetic head to be inspected. When the DC bias currents (I.sub.0, I.sub.1, I.sub.2) are supplied to the conducting wire, the impedances (Z.sub.0, Z.sub.1, Z.sub.2) corresponding to the DC bias currents are measured. When a ratio (.vertline.Z.sub.1 -Z.sub.0 .vertline./.vertline.Z.sub.2 -Z.sub.0 .vertline.) corresponding to an overwrite characteristic (OW) reaches to a predetermined value by lapping tip portions of an upper magnetic layer and a lower magnetic layer of the magnetic head, the lapping process of the magnetic head is finished.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.