Exposure tool for immersion lithography

The 193 nm immersion lithography is becoming the most likely candidate to succeed 193 nm dry lithography, and may extend down to the 45 nm ITRS technology node or beyond. A 0.85 numerical aperture (NA) full field immersion exposure tool was constructed as engineering evaluation tool. With this tool, the imaging of 65 nm half pitch with the depth of focus of 750 nm was demonstrated with scanning exposures, which means imaging capability is as high as expected. Two higher NA immersion tools are planned for production use, one is 1.07 NA tool with all-refractive projection optics at the timing of the 4th quarter of 2005, and the other is 1.30 NA tool with catadioptric projection optics in 2006. For high NA imaging of immersion or dry, polarized illumination is effective. Resist imaging data with 0.92 NA dry tool with polarized illumination are obtained