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Reinforcing the probes in the Water-Level-Probe equipment Disclosure Number: IPCOM000014464D
Original Publication Date: 2001-Oct-27
Included in the Prior Art Database: 2003-Jun-19

Publishing Venue



This invention solves the problem of the wafer-level-probe wires fatiging to failure. The wafer-level-probe wires are miniature bent wire probes welded to the probe substrate metallization. These probe wires make mechanical and thus electrical contact with the silicon wafer being tested. Each time the probe contacts a silicon wafer, it bends elastically along its length. The probe wire is thus fatigued. The fatigue damage is more in the region where the wire is welded to the substrate metallization, because it is here that the heat from the welding softens the wire. Soft wire sections fatigue more than the hard wire sections. With repeated cycles, some of the probe wires break in the region softened by welding. This invention solves the problem of the premature fatiguing of the probe wires by reducing the fatigue stress in the region where the probe wire is welded to the substrate metalliziation. The stress in this region is reduced by pouring and curing a layer of epoxy so as to embed the welded region and some length of the wire in the cured epoxy. As a result, the wire when bent will not be stressed in the welded region, because the epoxy will not allow deformation of the probe wire embedded with in the epoxy. The fatigue life of the probe wire will thus be improved and the wafer-level-probe will last longer. 1