Resolution and Depth of Focus Vs Exposure wavelength 2000 1500 ArF 193nm KrF 248nm -500 一DoF(NA-0.41) -1500 2)A0.6 um thick layer of resist has Q0=40 mJ/cm" and Qf= 160 mJ/cm. Calculate the resist contrast and CMtF. If the resist thickness is cut in half, Qf reduces to 70 mJ/cm while Qo is unchanged. Assuming NA=0.4, use the figure below to determine the minimum linewidthfor an aligner with S=1.0 using both resist thicknesses with a source of 365 nm. The figure below plots mtf of the aligner for a set of lines and spaces. The lines and spaces are of equal width(W), and the spatial frequency is normalized by the Rayleigh criteria, R. In other words, a normalized spatial frequency of 0.5, corresponds to a linewidth W equal tor(since the equivalent source spacing of the lines is 2W) 0.9 s=0.5 0.8 0.7 s=0 0.6 0.5 0.4 0.3 0.2 0.1 S=025 010203040.50.6070.809 Normalized spatial frequency(linesunit length) /(cutoff frequency)2 -2000 -1500 -1000 -500 0 500 1000 1500 2000 100 150 200 250 300 350 400 450 500 Resolution and Depth of Focus Vs. Exposure wavelength R (NA=0.41) DOF (NA=0.41) DOF (NA=0.41) Resolution and Depth of Focus (nm) Exposure wavelength (nm) ArF 193nm KrF 248nm 2) A 0.6 µm thick layer of resist has Q0 = 40 mJ/cm2 and Qf = 160 mJ/cm2 . Calculate the resist contrast and CMTF. If the resist thickness is cut in half, Qf reduces to 70 mJ/cm2 while Q0 is unchanged. Assuming NA = 0.4, use the figure below to determine the minimum linewidthfor an aligner with S = 1.0 using both resist thicknesses with a source of 365 nm. The figure below plots MTF of the aligner for a set of lines and spaces. The lines and spaces are of equal width (W), and the spatial frequency is normalized by the Rayleigh criteria, R. In other words, a normalized spatial frequency of 0.5, corresponds to a linewidth W equal to R (since the equivalent source spacing of the lines is 2W)