| Rapid development in technology and technics make the advent of high-quality complex optical systems; meanwhile bring them new big challenges as well. For instance, reducing exposure wavelength, adopting immersion technology and resolution enhancement technology (RET), making high numerical aperture lithography machines gone from32-nm node to22-nm node and beyond. As the features and performance are approaching the theoretical critical values, the precision of conventional scalar method for analysis becomes not enough, vector method that involves the vector nature of light should be adopted instead.In this paper, the significance and research status home and abroad of polarization analysis in high-quality complex optical systems are introduced firstly, and then the fundamental of polarization aberrations in optical systems, including polarization aberration function and thereof computational methods, are briefly summarized. Based on above theory, high NA lithography and large-scale laser system are chosen as two kind of sample systems to outline the polarization aberration and thereof control methods in real optical systems. Next, related program design work on functional module in optical software and analysis results achieved are presented. Finally, the polarization analysis of a real high NA refractive lithography system is made, where the anti-reflection coating, the absorption in coating and base materials and polarized illumination are taken into account to obtain a higher-reliability result. Several polarization parameters at every optical interface are calculated with optical software, such as transmission, phase, diattenuation and retardance, to achieve the effects of polarization on transmission performance and imaging performance. A polarization compensation scheme is designed based on the analysis results and applied into the lithography to see its effectiveness. The research significance and necessity of this issue are confirmed by above polarization analysis. |
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