Injection seeded F2 laser with line selection and discrimination

US6590922B2 · kind B2 · utility

Assignee

• Cymer, LLC · US

Inventors

• Eckehard D. Onkels · San Diego, US
• Richard L. Sandstrom · Encinitas, US
• Richard M. Ness · San Diego, US
• William N. Partlo · Poway, US
• Alexander I. Ershov · Escondido, US
• Choonghoon Oh · Temecula, US

Key dates

• Filing date: Jun 12, 2001
• Grant date: Jul 8, 2003
• Expiry date: Jul 19, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S3/2325
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A narrow band F2 laser system having two laser subsystems. The first laser subsystem is configured to provide a very narrow band pulsed beam at a first narrow wavelength range corresponding to a first natural emission line of the F2 laser system. This beam is injected into the gain medium of the second laser subsystem in a first direction where the beam is amplified to produce a narrow band pulsed output beam. The seed laser subsystem also produces a second pulsed beam at a second wavelength range corresponding to a second natural emission line of the F2 laser. This line is injected into the gain medium of the second laser subsystem in a second direction opposite said first direction. The second beam is amplified in the gain medium of the second laser subsystem depleting the gain medium of gain potential at the second wavelength range. (This amplified second beam is preferably wasted.) With the gain potential at the second undesired wavelength the range thus reduced the portion of light at the second wavelength range in the output beam is greatly reduced.