The ultra-violet partial coherence modulation transfer function for lithography

The critical dimension(CD) is main factor to determine the line width of semiconductor equipment fabricating ability for the smallest line width of produced electronic components. Modulation transfer function(MTF) has been popularly used to evaluation the optical system, due to the contrast of each line-pair in dimension analytically, however, while the light source is coherent or near coherent for the small dimension near the optical diffraction limit, the MTF is hard to achieve consistently. The study of ultra-violet partial coherence modulation transfer function is to calculate the 1-D and 2-D the line with anoptical design program, to estimate the MTF near the size of diffraction limit. It provides fabricating parameter for a 1-to-1 TSV lithographic system. By applying partial coherence analysis, the optimized relative numerical aperture (RNA) has found. As the system is built, the optimized performance should be expected.