What inspection variables should be evaluated?
Wafer marks, chip surfaces and edge chips may need different light paths. Compare coaxial and oblique illumination for each task.
What lighting geometry fits this inspection task?
Coaxial illumination sends light close to the camera viewing axis. It can help separate flat reflective areas from markings, depressions and scratches. Tilt, curvature and protective films can change the result, so align the light, lens and sample together.
Start below saturation and adjust alignment while watching the target feature. Test good and defective parts from different batches. Check the field edges, material texture and lens reflections. An even background is useful, but does not by itself support defect contrast.
Related product family?
LXV-3COX
Lighting for inspecting shapes, surfaces and small details.
Before choosing a configuration?
For selection, specify the field of view, smallest target feature, height variation, cycle time and installation space. Use the specific product page and drawing to verify electrical ratings, dimensions and compatibility.
Comparing wafer bright-field and dark-field?
Use the same wafer region to compare a reflected bright background with a dark-field arrangement. Record which defects scatter light and which interrupt a uniform reflection. Camera focus and exposure must remain controlled during the comparison.
Include edge chips, fine scratches and clean patterned regions as appropriate. Test several orientations and locations. Choose separate lighting states if one view cannot distinguish all required features from normal pattern variation.
What do the optical setup and sample images show?
