Wafer Geometry Inspector

Measurement principle

The central measuring unit consists of 3 light-sectioning sensors which are arranged one above the other. These sensors all measure a certain sub-section of the wafer edge at the same time. The resulting 3 sub-profiles are automatically combined to form a total profile.

The measurement can then be repeated at any number of positions on the wafer circumference. The repeat accuracy is increased by averaging all the recorded profiles.