A novel test technique for MCM substrates

This paper describes a novel and low-cost test technique that is capable of detecting process related defects such as opens and shorts in multichip module (MCM) substrates. This method is an alternative to existing test methods such as electron beam, capacitance, resistance, and electrical module test (EMT) techniques which are either expensive in terms of test equipment, are cumbersome due to the requirement of multiple probes, have low throughput or provide poor defect coverage. The proposed test method applies a stimulus through a resonator at only one end of the interconnect using a single-ended probe. By measuring the attenuation of the test stimulus due to pole movement relative to known attenuation measurements, interconnect faults such as near-opens, near-shorts, opens, and shorts can be detected. The total test time is projected to be similar to a capacitance method and the hardware cost of test equipment is low. This paper discusses the theoretical details, simulation results, resolution, implementation, and validation of the technique.