| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an overlay key for measuring overlay precision between a first thin film and a second thin film formed on a semiconductor substrate. <P>SOLUTION: On the first thin film, a first mark 110 including a first pattern extending in a first direction with a first pitch is formed while on the second thin film, a second mark 120 including a second pattern adjacent to the first mark and extending in the first direction with a second pitch substantially the same as the first pitch is formed. The overlay precision is calculated using the positional information of first interference fringes and second interference fringes formed by acquiring a first image and a second image from the first mark 110 and the second mark 120, and by overlapping a test image having a third pitch on the first image and the second image. <P>COPYRIGHT: (C)2007,JPO&INPIT |
