High resolution optical lithography method and apparatus having excimer laser light source and stimulated Raman shifting
US4458994A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1983 |
| Grant date | Jul 10, 1984 |
| Priority date | — |
| Expiry date | Jun 7, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/30
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical lithography method and apparatus in which a pulsed excimer laser produces at least one fundamental output which is directed to expose a photosensitive medium. The output is highly non-gaussian and has sufficient power so that full exposures can be accomplished within a few seconds. An alternate light source is provided by directing the excimer laser output to a Raman cell having a suitable Raman medium contained therein. At least one secondary wavelength is produced by stimulated Raman scattering and the output of the Raman cell is directed to expose a photosensitive medium. A mixture of more than one excimer gas can also be provided in the excimer laser to produce one fundamental output for each excimer gas present in the mixture. These outputs can be directed to expose a photosensitive medium directly. Alternatively, these outputs can be directed to a Raman cell having either a single Raman medium or multiple Raman media in a suitable mixture and directing the output from the Raman cell to expose the photosensitive medium.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.