International Business Machines Corporation
Test probe assembly with fiber optic leads and photodetectors

Abstract:

A test probe assembly for determining the integrity of a test pad of a semiconductor wafer. The test probe assembly includes a probe card, a plurality of test probes mounted to the probe card, a fiber optic lead mounted to each test probe and arranged to direct incident light toward individual test pads of the semiconductor wafer and a plurality of photodetectors arranged about the probe card. Individual photodetectors are configured to receive light reflected off a dielectric coating of the test pad corresponding to a first set of light rays emitted by the test pad and configured to receive light reflected off a metallic base of the test pad corresponding to a second set of light rays emitted by the test pad, and to generate first and second output signals associated with the first and second sets of light rays to create image data of the individual test pads.