Self-aligned pole tips
US4436593A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 13, 1981 |
| Grant date | Mar 13, 1984 |
| Priority date | — |
| Expiry date | Jul 13, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49046
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method is disclosed for precisely aligning the pole tips of a thin film magnetic head. Two separate metallic layers, such as Permalloy (Ni-Fe alloy) are separated by a layer of insulating material such as silicon dioxide or AL.sub.2 O.sub.3 which will serve as the insulative spacer of the final magnetic head. A photo-resist is applied to the surface of the top metallic layer in an imagewise configuration to establish the shape of the top pole. The top pole is then etched and the photo-resist removed. The top electrode is then encapsulated with a protective metal and is used as a mask during the chemical etching of the insulative layer, the bottom electrode being used as an etch stop. This integral structure is then used as a mask during the chemical etching of the bottom electrode, resulting in pole tips which are precisely aligned.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.