Method for shaping pole pieces of magnetic heads by chemical mechanical polishing
US6510022B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 15, 2000 |
| Grant date | Jan 21, 2003 |
| Priority date | — |
| Expiry date | Feb 15, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49052
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The thin film magnetic head of the present invention includes an improved P2 pole tip/yoke interface structure. The interface structure includes yoke material that is formed in a concave curved shape at the interface between the P2 pole tip and the yoke, such that a right angle interface between the P2 pole tip and the yoke is eliminated. The process for forming the P2 pole tip/yoke interface includes a second CMP polishing step that is performed on the surface of the write head wafer subsequent to the plating of the P2 pole tip thereon, and subsequent to a first CMP step. This second CMP step utilizes a relatively soft polishing pad and an acidic polishing slurry having a pH within the range of approximately 1 to approximately 5, and preferably approximately 2.5. The acidic polishing slurry contains a chemical agent which preferentially attacks the P2 pole tip material, such that the second CMP step results in the recession of the upper surface of the P2 pole tip relative to the dielectric layer surrounding it, as well as the significant rounding of the upper edges of the dielectric trench in which the P2 pole tip is formed. Thereafter, when the yoke is plated onto the P2 pole tip…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.