APPARATUS FOR PROJECTING A SERIES OF IMAGES ONTO DIES OF A SEMICONDUCTOR WAFER

摘要

Apparatus for Projecting a Series of Images Onto Dies of a Semiconductor Wafer The apparatus forms one-to-one reticle images on a wafer. The apparatus includes means for holding a reticle containing an image pattern corresponding to the size of the desired wafer pattern. An illumination system substantially uniformly illuminates the reticle pattern. A one-to-one stationary projection optical system projects an image of the reticle pattern onto a predetermined focal plane. Suitable means such as a vacuum chuck holds the wafer. An alignment system steps and orients a wafer chuck to register markings on the individual sides of the wafer with corresponding markings on the reticle. A fluid servo system acts on the chuck to hold at least a portion of the wafer in the predetermined focal plane of the projection optical system.