The Impact of Polarization on Metrology Performance of the Lateral Shearing Interferometer

The semiconductor industry is aggressively pushed to produce smaller and smaller feature size from their existing base of lithography system, wavefront aberration should be derived by comparing ideal and real wavefronts at the wafer plane of a high resolution lithography system. We propose the IIWS (Integrated Interferometer Wavefront Sensor) system. On the base of traditional lateral shearing interferometer, two-dimensional phase-shifting shearing interferometry and vectorial optical analysis are used in this paper. By adjusting polarization state and polarization distribution, the metrology accuracy of the wavefront aberration of the system, which is significant for the modern semiconductor industry, is greatly increased.