Modified optics for imaging of lens limited subresolution features
US6411367B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 1999 |
| Grant date | Jun 25, 2002 |
| Priority date | — |
| Expiry date | Mar 29, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70225
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A system and method is disclosed for enhancing an optical lithography process by capturing light diffracted from a mask having features to be exposed onto a wafer. In one embodiment, a system of the present invention has in place a mask, a wafer and a reduction lens such that the reduction lens is placed between the mask and the wafer in order to direct and expose the mask's features onto the wafer. Furthermore, a reflective member is disposed proximate to the reduction lens. In order to achieve finer resolution of the mask image on the wafer, this reflective member captures diffracted light diffracting beyond the reduction lens and redirects the diffracted light to pass through the reduction lens such that the diffracted light is redirected onto the wafer. In so doing, the reflective member resolves the mask image on the wafer in more detail than is possible by an optical lithography process using no such reflective member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.