01275nas a2200121   4500008004100000245013000041210006900171260000800240520064900248100002000897700000500917856023100922       2001                        eng d00aUnited {States} {Patent}: 6294296 - {Method} and device for mutually aligning a mask pattern formed in a mask and a substrate0 aUnited States Patent 6294296 Method and device for mutually alig  csep3 aIn a method for mutually aligning a mask pattern formed in a mask 1 and a substrate 2, on which the mask pattern is to be imaged, by using setting marks 12a, 12b and 13a or 13b in the mask 1 and in the substrate 2, the alignment is performed with the aid of an imaging system and a light beam with polarized light 9. A phase shift for the first diffraction orders 20 is undertaken in the beam path 9a, 9b. Higher diffraction orders 21 and unwanted light are filtered out after the phase shift, and after the filtering out the light beams of the first diffraction orders 20 are detected, and the result is evaluated for the purpose of alignment.1 aWeigl, Bernhard1 a  uhttp://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=%2Fnetahtml%2FPTO%2Fsearch-bool.html&r=28&f=G&l=50&co1=AND&d=PTXT&s1=%22Weigl%3B+Bernhard%22.INNM.&OS=IN/%22Weigl;+Bernhard%22&RS=IN/%22Weigl;+Bernhard%22