| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent the occurrence of errors in sensing alignment marks due to scratches or dirt on the marks or due to faulty drawing of the same. <P>SOLUTION: The alignment mark searching unit comprises an imaging section for partially imaging the specimen surface, a locomotion section for changing the region for imaging by causing a relative movement between the specimen and the imaging section, a sensing section for sensing alignment marks in the image taken, a registration section for registering in advance the expected positions of three or more alignment marks, and an imaging controller for sequentially imaging the expected positions registered in the registration section by driving the imaging section and the locomotion section until a pair of alignment marks is sensed. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
