Patent ID: 6198535
Filing Date: 2001-03-06
Classification: G03F

Abstract:
A wafer alignment system for alignment of a wafer, wherein the wafer comprises a first surface and a second surface, and wherein the first surface is reserved for transferring a pattern thereon, and the second surface comprises a plurality of alignment marks, the wafer alignment system comprising:a wafer supporting-unit for supporting the wafer on its second surface, wherein the wafer supporting unit comprises a plurality of apertures, and wherein the apertures are located correspondingly to the alignment marks, and the wafer supporting-unit also comprises a fiducial mark used for setting the wafer supporting-unit to a reference location in which the fiducial mark and the wafer have no overlap; andan alignment unit for emitting a plurality of guiding rays, and aligning the wafer by checking the guiding rays, wherein the guiding rays are reflected by the alignment marks right above the apertures before being checked.