In 45nm technology node and beyond with hyper NA and Off-axis Illumination (OAI) lithography, mask induced
polarization effect is remarkable. At this scale, traditional Kirchhoff approximation, in which the masks are considered to
be infinitely thin objects, is no longer valid. Rigorous three-dimensional (3D) mask model is required for precise
evaluation of mask diffraction. In this paper, a general 3D mask model based on the rigorous coupled-wave analysis
(RCWA) is presented, and the change of polarization state as a function of mask and incident light properties is
evaluated. The masks considered are the binary chrome mask and 10% Si-Si3N4 attenuated phase shifting mask. The results show that the mask induced polarization effects depend on the mask and incident light properties, such as mask material, absorber thickness, mask pitch, feature size, the polarization and incident angle of the light.