Lithographic apparatus and method

摘要

A device manufacturing method includes conditioning a beam of radiation using an illumination system. The conditioning includes controlling an array of individually controllable elements (33a-33e) and associated optical components (16) of the illumination system to convert the radiation beam into a desired illumination mode, the controlling including allocating different individually controllable elements to different parts of the illumination mode in accordance with an allocation scheme, the allocation scheme selected to provide a desired modification of one or more properties of the illumination mode, the radiation beam or both. The method also includes patterning the radiation beam with a pattern in its cross-section to form a patterned beam of radiation, and projecting the patterned radiation beam onto a target portion of a substrate.