Illuminator for photolithography device, has pair of compensating biplates with illumination transmission co-efficient varied according to variation direction, where biplates are mounted on support

摘要

The illuminator has a pair of compensating biplates (9, 10) with an illumination transmission co-efficient varied according to a variation direction (14), where the variation direction is perpendicular to a direction (13) normal to the biplates. The biplates are displaced, with respect to an illumination source, along a displacement direction parallel to the variation direction. The biplates are mounted on a support, which includes a displacement unit for displacing the biplates. An independent claim is also included for a method of apodization of illumination of a mask in an illuminator.