Photoresist tapering process
US4705597A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1985 |
| Grant date | Nov 10, 1987 |
| Priority date | — |
| Expiry date | Apr 15, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31138
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Photoresist apertures having tapered sidewalls can be provided by first opening the aperture in accordance with ordinary practice followed by the exposure of the photoresist to a suitable energy source such as a flood exposure to wideband light, the heating of the photoresist to round the peripheral edges of the aperture and the exposure of the thus pretreated photoresist to an environment which removes photoresist from the inside wall of the aperture until the desired tapered profile is obtained. In the preferred practice of the invention, the pretreated photoresist is removed from the inside wall of the aperture through exposure to a dry oxygen plasma etch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.