ABSTRACT
Extreme ultraviolet lithography (EUVL) is an optical lithography technology that has many similarities to conventional optical lithography. Optics contamination has been an issue with almost all lithography technologies in the past, and this is not different for EUVL. EUVL would level the playing field for foundries to be able to help fabless companies to compete with Intel or Samsung. The shorter wavelength, compared with that used for immersion lithography tools, can provide improvement in resolution by a factor of up to 4. For use in a lithography system, a source of EUV is not simply an emitting plasma. The EUV light needs to be collected and directed toward the lithography exposure tool using reflective collector optics as efficiently as possible. To be useful for EUVL, the main source parameters that need to meet specific requirements are power, spectral content, etendue, dose stability, and lifetime.
