International Sematech has contracted with Optical Research Associates (ORA) to extend the capabilities of their Code V optical design software to support analysis of advanced optical systems for 157 nm microlithography. Specifically, this will involve the development of novel algorithms for the modeling of birefringent crystalline materials. The existing capabilities in Code V allow the simulation of uniaxial birefringent crystals and symmetric, stress-induced birefringence. This contract calls for ORA to extend these capabilities to accurately simulate the inherent behavior of transmissive materials such as CaF2. These materials exhibit complex, multi-axial, angle dependent birefringence effects at 157 nm.Because of the extreme performance demands placed on 157 nm microlithography systems, this level of increased modeling accuracy is critical in enabling the semiconductor industry to successfully transition their process to this wavelength. Work is scheduled for completion in November. ORA is a solutions supplier to the optics and optical telecommunications industries.