Exposure method and apparatus
US5902716A · kind A · utility
8Cited by
5References
8Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 5, 1996 |
| Grant date | May 11, 1999 |
| Priority date | — |
| Expiry date | Sep 5, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/0275
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
After a photoresist is applied onto a wafer, a contrast enhancement material (CEM) layer is applied onto this photoresist. A pattern is projected through this CEM layer onto the photoresist. Next, this CEM layer is removed from the photoresist and thereafter a new CEM layer is again applied onto the photoresist. Another pattern is projected through this new CEM layer onto the photoresist, whereby the photoresist is exposed in accordance with a composite pattern of the two patterns. This composite pattern can surpass the resolution limit of projection optical system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.