Symmetric polarization aberration compensation method based on scalar aberration control for lithographic projection lens

摘要

To minimize the adverse effects of polarization aberrations in the projection optical system, methods to compensate thepolarization aberrations are required for high resolution lithography. In this paper, we propose a symmetric polarizationaberration compensation method based on scalar aberration control for lithographic projection lens. This method focuseson the compensation of polarization aberrations induced by radially symmetric retardances. The foundation of thecompensation method is the linear relationship between conventional even aberration and polarization aberration inducedby radially symmetric retardances. The compensation accuracy is dependent on the even aberration adjustment accuracyof the projection lens and the sensitivity of the mask pattern to even aberrations. By this polarization aberrationcompensation method, the lithographic process window can be improved obviously.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.