Coplanarity
Bumps normally consist of highly reflective material and are difficult to measure for an optical system. Especially the etches can be a problem for traditional 3D-systems and only a small area in the middle of the bump is detected.
Bumps normally consist of highly reflective material and are difficult to measure for an optical system. Especially the etches can be a problem for traditional 3D-systems and only a small area in the middle of the bump is detected.