Periodic Patterns and Techniques to Control Misalignment Between Two Layers

摘要

A method and system to measure misalignment error between two overlying or interlaced periodic structures are proposed. The overlying or interlaced periodic structures are illuminated by incident radiation, and the diffracted radiation of the incident radiation by the overlying or interlaced periodic structures are detected to provide an output signal. The misalignment between the overlying or interlaced periodic structures may then be determined from the output signal.

主权项

1. A method for processing and measuring a device, said device having a first periodic structure, said method comprising:
measuring the first periodic structure by illuminating the first periodic structure with incident radiation and by detecting diffracted radiation from the illuminated portions of the first periodic structure; after the first periodic structure has been measured, forming a second periodic structure in a region of the device, where the first and second periodic structures are present in said region; and measuring a relative position between the first and second periodic structures by illuminating the first and second periodic structures with incident radiation and by detecting diffracted radiation from the illuminated portions of the first and second periodic structures in said region.