| 摘要 |
Divided reticles are disclosed for use in charged-particle-beam (CPB) microlithography. The reticles include multiple subfields separated from each other by skirts and struts, and exposure-alignment marks situated in the skirts in association with respective subfields. During exposure, the respective positions of the exposure-alignment marks are detected and appropriate image-position and other corrections are made as required to ensure optimal stitching accuracy of the subfield images on the lithographic substrate. The exposure-alignment marks are formed on the reticle simultaneously with forming the pattern on the reticle using a pattern-drawing apparatus. By facilitating the achievement of optimal stitching of subfield images on the substrate, extreme demands for positional accuracy conventionally placed on the pattern-drawing apparatus are eliminated. |
