Patent ID: 7969564

Claim:
A system for defect localization in a test structure, comprising: a stage configured to support and position the test structure within the system; means for illuminating an electro-optically active layer, wherein (i) the electro-optically active layer coats only a top surface of the test structure, (ii) said test structure includes a conductor, and (iii) the electro-optically active layer provides an indication about an electrical status of the conductor; a detector configured to detect light scattered or reflected from the electro-optically active layer; means for providing an alternating current electrical signal coupled to the conductor of the test structure, said alternating current electrical signal characterized by multiple phases and said means for providing further configured to synchronize phases of the alternating current electrical signal with image captures of the test structure; and a processor configured to (i) generate a first image of the test structure during a first phase of the electrical signal based on detection signals received from the detector, (ii) generate a second image of the test structure during a second phase of the electrical signal based on detection signals received from the detector, and (iii) process the first and second images in order to locate a defect in the test structure.