| 摘要 |
A system for inspecting a backside surface of a wafer with multi-channel focus control includes a set of inspection sub-systems including a first inspection sub-system positioned and an additional inspection sub-system. The first and additional inspection sub-systems include an optical assembly, an actuation assembly, where the optical assembly is disposed on the actuation assembly, and a positional sensor configured to sense a position characteristic between a portion of the optical assembly and the backside surface of the wafer. The system also includes a controller configured to acquire one or more wafer profile maps of the backside surface of the wafer and adjust a first focus position of the first inspection sub-system or an additional focus position of the additional inspection sub-system based on the received one or more wafer profile maps. |
