Method of ensuring electrical contact between test probes and chip pads through the use of vibration and nondestructive deformation

摘要

A method of testing chips having each a plurality of contact pads, the chips are arranged on a semiconductor wafer or on a printed circuit and are tested with a test system having a test head provided with a plurality of probes, the method comprising the steps of: a) moving the test head and the chips towards each other by a distance which is smaller than a predefined maximum length; b) determining the presence of a contact between the probes and the contact pads by performing an electrical test via the probes to yield a predetermined electrical resu and c) repeating steps a) and b) until the electrical test no longer yields the predetermined electrical result or until the predefined maximum length is reached. The invention also provides for a test system for carrying out the inventive method.