Reduction in damage to optical elements used in optical lithography for device fabrication
US5891605A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 16, 1996 |
| Grant date | Apr 6, 1999 |
| Priority date | — |
| Expiry date | Jan 16, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70241
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical lithographic process and system for fabricating devices which includes an optical subsystem for reducing the rate of damage to the system's optics caused by exposure to energy pulses from an exposure source. The optical subsystem transforms a primary energy pulse from the exposure source into N secondary pulses, where N is .gtoreq.2 with a delay provided between each secondary pulse so as to reduce the peak intensity of the energy pulse being transmitted through the optical system. The subsystem redirects the secondary pulses spatially to satisfy source requirements for appropriate lithographic illuminators. Furthermore, the subsystem may be an intrinsic design feature of the illuminator or exposure source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.