Ion-projection lithographic apparatus with means for aligning the mask image with the substrate

摘要

An apparatus and method for the fine alignment of a mask with a substrate in ion-projection lithography, e.g. for the production of integrated circuit chips, utilizes a multipole, an axial magnetic field generator and a scale controlling projection lens in the path of the beam. The mask is provided with markings which are imaged on the substrate and brought into registry with corresponding markings thereon utilizing pairs of detectors associated with each linear marking and responsive to secondary emission of the ion-beam marking projected on the substrate. All of the markings are straight lines.