System and method for gradient thermal analysis by induced stimulus

摘要

A thermal gradient is induced in a device-under-test (DUT) and used to determine the location of a defect. In one embodiment, a laser creates a moving thermal gradient from a test site on the DUT and a respective time of flight for the thermal gradient to trigger a condition associated with the defect is determined. Repeating the time of flight testing at additional test site provides information used to trilaterate the defect in three dimensions. Alternately, a static thermal gradient is induced across at least a portion of the DUT along a first axis. The thermal gradient is incrementally walked along the first axis until the condition associated with the defect is triggered, thereby defining a first region. The thermal gradient is then induced along a second axis of the DUT and the process is repeated to define a second region. The location of the defect is determined to be the intersection of the first region with the second region.

主权项

1. A method, comprising:
selecting a plurality of test sites on a device-under-test (DUT), each of the plurality of test sites having respective coordinates; for each of the plurality of test sites, heating the test site at a controlled rate to create a thermal wave that propagates across the DUT and capturing an elapsed time until the heating triggers a known condition at an anomaly that is located a respective distance from the test site; and using the respective elapsed time to determine the respective distance between each of the plurality of test sites and the anomaly, wherein the respective coordinates of each of the plurality of test sites and the respective distances from the anomaly are used to determine the location of the anomaly by trilateration.