There is some problems I cannot be solve... Hope all of your can help me...

(1)We found that there is many board can be escape from E-test...
After micro-section analysis, we found that there is still base copper on trace
open location.
We can said that the problem is dish down ... There is still connected but the
resistance is greater than normal one...

What is the cause of this defect?
Is there any reliable method to detech it?
Is there any apparatus can detech the nick circuit problem expect AOI.?

(Embedded image moved to file: pic22705.pcx)

Best Regard,
nicholas lai