Isotropic deposition for trench narrowing of features to be created by reactive ion etch processing
US6770209B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 2002 |
| Grant date | Aug 3, 2004 |
| Priority date | — |
| Expiry date | Nov 16, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49032
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An isotropic deposition method for trench narrowing of thin film magnetic write head features to be created by reactive ion etching. According to the method, a photolithographically defined photoresist trench is formed over a hardmask and underlying polymer layer as part of tri-layer resist process. Instead of performing the usual hardmask and polymer etching steps using the photoresist mask pattern, a spacer layer is deposited isotropically or directionally at an angle to cover the vertical side walls of the trench. The spacer layer is etchable by the hardmask etch process but resistant to the polymer etch process. When the hardmask etch process is performed, the spacer layer material applied to the trench side walls remains intact, thereby defining a narrowed trench that is extended by the subsequent base layer etch process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.