Abstract: Resist contrast is related to usable depth-of-focus (UDOF) for I-line and DUV stepper lenses through the resists process linearity function. Results, supported by simulations in the resist image, show that stepper field center-edge critical dimensional offsets, which decrease UDOF, increase as resist contrast decreases. Measurements on intra-field CDs show that their uniformity decreases as processes reach non-linear processing regimes. !3
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