Maskless, reticle-free, lithography
US5691541A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | May 14, 1996 |
| Grant date | Nov 25, 1997 |
| Priority date | — |
| Expiry date | May 14, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70725
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A lithography system in which the mask or reticle, which usually carries the pattern to be printed onto a substrate, is replaced by a programmable array of binary (i.e. on/off) light valves or switches which can be programmed to replicate a portion of the pattern each time an illuminating light source is flashed. The pattern of light produced by the programmable array is imaged onto a lithographic substrate which is mounted on a scanning stage as is common in optical lithography. The stage motion and the pattern of light displayed by the programmable array are precisely synchronized with the flashing illumination system so that each flash accurately positions the image of the pattern on the substrate. This is achieved by advancing the pattern held in the programmable array by an amount which corresponds to the travel of the substrate stage each time the light source flashes. In this manner the image is built up of multiple flashes and an isolated defect in the array will only have a small effect on the printed pattern. The method includes projection lithographies using radiation other than optical or ultraviolet light. The programmable array of binary switches would be used to cont…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.