Development of a system for automatic surface inspection of wafers in combination with a measurement microscope.
The development involved a system for wafer inspection. A measurement microscope scans all relevant surface areas of the wafer. The measurement microscope is also able to swap lenses by means of an automatic lens indexer, which facilitates inspection at various magnifications.
The structure of the wafer is stored in the machine vision system. By constantly comparing the position of the measurement microscope with the structure data, it is possible to identify wafer defects even in highly structured areas.