Excimer or molecular fluorine laser system with precision timing

US7308013B2 · kind B2 · utility

Assignee

• Lambda Physik AG · DE

Inventors

• Dirk Basting · Fort Lauderdale, US
• Sergei V. Govorkov · Mountain View, US
• Rainer Paetzel · Dransfeld, DE
• Igor Bragin · Göttingen, DE
• Andreas Targsdorf · Gardelegen, DE

Key dates

• Filing date: Nov 3, 2003
• Grant date: Dec 11, 2007
• Expiry date: Nov 18, 2024

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01S3/2258
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A Master Oscillator (MO)—Power Amplifier (PA) configuration (MOPA) can be used advantageously in an excimer laser system for micro-lithography applications, where semiconductor manufacturers demand powers of 40 W or more in order to support the throughput requirements of advanced lithography scanner systems. The timing of discharges in discharge chambers of the MO and PA can be precisely controlled using a common pulser to drive the respective chambers. The timing of the discharges further can be controlled through the timing of the pre-ionization in the chambers, or through control of the reset current in the final compression stages of the pulser. A common pulser, or separate pulser circuits, also can be actively controlled in time using a feedback loop, with precision timing being achieved through control of the pre-ionization in each individual discharge chamber. Yet another system provides for real-time compensation of time delay jitter of discharge pulses in the chambers.