Abstract: In a multiple-exposure lithographic process a developed resist pattern derived from a first exposure is present within a second resist layer that is exposed in a second exposure of the multiple-exposure lithographic process. The second mask pattern used in the second exposure process includes at least one localized adjustment to at least one feature thereof to compensate for scattering effects of the developed resist pattern that is present when the second exposure is performed.

Abstract: In a multiple-exposure lithographic process a developed resist pattern derived from a first exposure is present within a second resist layer that is exposed in a second exposure of the multiple-exposure lithographic process. The second mask pattern used in the second exposure process includes at least one localized adjustment to at least one feature thereof to compensate for scattering effects of the developed resist pattern that is present when the second exposure is performed.

Abstract: A method is provided for compensating for the effect of flare lithographic apparatus. The method includes establishing a power spectral density (PSD) indicative of the spatial frequency of the stray radiation produced by a projection system, and determining, from the PSD, a modulation transfer function (MTF) relating the PSD to a pattern applied by a patterning device to take the effect of flare on the pattern image into account. The MTF is then used to determine the effect of flare on a critical dimension (CD) of the pattern image, and a relationship is established between any change in the CD of the pattern image and a change in the CD of the pattern. The patterning device may then be designed in such a way as to at least partially offset the effect of flare on the CD of the pattern image.