Reliable high power injection locked 6 kHz 60W laser for ArF immersion lithography

The Argon Fluoride (ArF) immersion lithography is now shifting to mass production phase for below 45nm node. For a laser light source in this node, narrower and more stable spectrum performance is required. We have introduced GT61A ArF laser light source (60W/6kHz/10mJ/0.35pm) with spectrum E95 stabilization system which meets these requirements. The narrow and stabilized spectrum performance was achieved by developing an ultra line narrowing module and Bandwidth Control Module (BCM). It contributes to the reduction of differences of the spectrum during exposure over a wafer, wafer to wafer, during machine lifetime and machine to machine for every light source. Stable laser performance is obtained for mass production. The GT61A integrated on a common and already reliability-proven GigaTwin (GT) platform, and its inherited reliability is proved with the availability over 99.5% in the field.