Two chamber F2 laser system with F2 pressure based line selection
US6798812B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 2002 |
| Grant date | Sep 28, 2004 |
| Priority date | — |
| Expiry date | Nov 12, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/2308
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides an injection seeded modular gas discharge laser system capable of producing high quality pulsed laser beams at pulse rates of about 4,000 Hz or greater and at pulse energies of about 5 to 10 mJ or greater for integrated outputs of about 20 to 40 Watts or greater. Two separate discharge chambers are provided, one of which is a part of a master oscillator producing a very narrow band seed beam which is amplified in the second discharge chamber. The parameters chamber can be controlled separately permitting optimization of wavelength parameters in the master oscillator and optimization of pulse energy parameters in the amplifying chamber. A preferred embodiment is a F2 laser system configured as a MOPA and specifically designed for use as a light source for integrated circuit lithography. In this preferred embodiment, both of the chambers and the laser optics are mounted on a vertical optical table within a laser enclosure. In the preferred MOPA embodiment, each chamber comprises a single tangential fan providing sufficient gas flow to permit operation at pulse rates of 4000 Hz or greater by clearing debris from the discharge region in less time than the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.