Patent ID: 8107054

Claim:
A method, comprising: providing a microlithographic projection exposure apparatus having an illumination system and a projection objective; illuminating a pupil plane of the illumination system with light; and modifying, in a plane of the projection objective, at least one parameter of the light passing through the plane of the projection objective, wherein: the at least one parameter is selected from the group consisting of a phase of the light, an amplitude of the light and a polarization of the light; at least two diffraction orders of the light are modified in mutually different ways so that a mask-induced loss in image contrast obtained in the imaging of the structures is reduced compared to performing the method without modifying the at least one parameter, and a lateral offset between a first interference image and a second interference image is reduced compared to performing the method without modifying the at least one parameter, the first interference image being obtained in a first illumination direction, and the second interference image being obtained in a second illumination direction.