Lithographic characterization of evanescent wave imaging systems

Solid immersion lithography has been investigated as a successor to liquid immersion lithography as a single exposure option for the 32 nm node. Current demonstrations have been limited to interferometric imaging. We model the solid immersion lithography process rigorously, including the evanescent wave phenomena, in a commercial lithography simulator. The lithographic process space is explored for conditions such as process window, resist thickness, gap width, and gap material. Vector imaging, followed by full resist kinetics and development, is performed for all calculations. Mask error factor, CD through pitch, and other issues significant to lithography are explored.