Process for projecting at least two masks onto a substrate in integrated circuit production uses lens and mask combination on test structure to minimize deviations

摘要

A process for projecting at least two masks of a mask set onto a substrate in integrated circuit production comprises determining lens errors or positional adjustments by using three lenses (51,52,53) and two masks (61,62) with test structures (41,42). The combination giving the smallest difference is then chosen.