Registration and alignment technique for X-ray mask fabrication

摘要

An X-ray mask includes one or more X-ray transparent mask windows and at least one pattern-to-mask alignment mark etched into the mask substrate from the same side as the mask windows. The pattern-to- mask alignment marks can be etched at the same time as the mask windows and are detectable from the front surface of the mask substrate by an electron beam lithography system prior to creating the circuit pattern. The alignment marks are detected by the absence of backscattered electrons at the pattern-to-mask alignment marks.