Prediction of imaging performance of immersion lithography using high refractive index fluid

A hyper-NA lithography tool is used in production of the latest devices. In the next generation immersion lithography, issues that had so for neglected had to be considered because NA of illumination optics is larger than conventional tools. Here, items were listed up for accurate prediction of imaging by optical simulation. These were transmittance of illumination rays to the mask, mask induced effects such as polarization and aberration, and pellicle induced effect. These were depending on incident angle. Therefore consideration of angle dependency of these effects was necessary for more accurate imaging simulation. We presented the requirements for simulation to facilitate discussion of the imaging performance of below 40 rum hp pattern node immersion lithography.