Approach to increase the resolution of dense line/space patterns for 0.18 micron and below design rules using attenuating phase shifting masks
US6210841A · kind A · utility
12Cited by
6References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 7, 1999 |
| Grant date | Apr 3, 2001 |
| Priority date | — |
| Expiry date | Sep 7, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/36
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A mask and method of forming a pattern on an integrated circuit wafer having regions of dense line/space patterns and regions of isolated lines or widely spaced line/space patterns. The mask uses a binary mask pattern to form the dense line/space region and an attenuating phase shifting mask pattern to form the isolated line or widely spaced line/space region. Scattering bars are used in the widely spaced line/space region of the mask to improve depth of focus. The method uses the mask in a projection exposure system to expose a layer of photosensitive dielectric on an integrated circuit wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.