摘要 |
A system for inspecting a component is provided. The system includes an interferometer having a coated mirror, such as a coating that allows only a fraction of light to pass, where the coating has a predetermined thickness. An interference inspection system receives reflected light from the component through the interferometer and determines whether interference is occurring at each of two or more predetermined areas, such as at point corresponding to a bump contact and at a second point corresponding to a substrate. The thickness of the coating is related to a height difference between two or more of the predetermined areas, such as by creating interference at both areas by changing the reflection path length by an amount required to cause simultaneous interference fringing for a designed height difference.
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