Ultra line narrowed injection lock laser light source for higher NA ArF immersion lithography tool

The GT61A ArF laser light source with ultra line narrowed spectrum, which meets the demand of hyper NA (NA > 1.3) immersion tool, is introduced. The GT61A aims at improving spectrum performance from value E95 0.5pm of GT60A. The spectrum performance 0.3pm or less was achieved by developing an ultra line narrowing module newly. Moreover, in 45nm node, since it indispensably requires OPC (optical proximity correction) and a narrower process window, improved stabilization of spectrum performances was performed by bandwidth control technology. Newly designed Bandwidth Control Module (BCM) includes high accuracy measurement module which support the narrower bandwidth range and active bandwidth control module. It also contributes to the reduction of the tool-to-tool differences of the spectrum for every light source.