Method and system for dual reticle image exposure
US6611316B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 27, 2002 |
| Grant date | Aug 26, 2003 |
| Priority date | — |
| Expiry date | Feb 27, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70358
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides a method and system for simultaneously imaging at least two reticles onto a substrate. According to the present invention, the wafer is passed through the exposure sequence once with images from the reticles being exposed simultaneously onto the wafer. The throughput of the system is effectively maintained at the standard single pass throughput level or twice that of conventional systems. In one embodiment, the present invention produces two reticle images side-by-side in the exit pupil of the optics of a step and scan wafer exposure system. The scanning action of the exposure tool then effectively superimposes the two images during the exposure of the wafer. Each image exposes the photoresist as the wafer is scanned through the image field synchronously with the scanning of the reticles. According to one embodiment, the image scanning is synchronized so that two required images are superimposed. According to another embodiment, the two images can be independently focused and aligned.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.