New generation photomasks: 193-nm defect printability study

Today some IC manufacturers obtain finer circuit geometries by adding scatter bars (SB) to conventional binary masks as an efficient resolution enhancement technique (RET).1 These SB perform best when they are wide. However, to achieve better resolution and wider process windows modern stepper equipments feature lower wavelengths and higher numerical aperture lenses. These new steppers require narrower scatter bars to prevent them from printing on the wafer, and their effectiveness as a RET is diminishing as we follow the stepper technology 'roadmap'.