| 摘要 |
High atomic number metals or compounds are used as electron beam registration alignment marks on low atomic number substrates; this combination produces enhanced secondary and backscattered electron video signals over topographical alignment marks of homogeneous materials. To augment the enhanced signal contrast, pairs of alignment marks are placed very close together (less than or equal to 3 micrometers), from which the gap between the pair produces the augmented, enhanced signal contrast. In particular, the backscattered electron signal is enhanced when detected with an energy sensitive collector such as a silicon diode detector. |
