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We fabricated an apparatus for manipulation and welding of fine metal objects using a probe. The apparatus is composed of a work probe of a tungsten alloy needle, stages, a DC power supply, and an observation system. The work probe is held vertically above a gold substrate placed on stages to control the relative position against the work probe. The DC power supply is equipped to apply voltage of 0-10kV between the work probe and the substrate. One application of the apparatus is to repair probe cards. Thousands of contact probes (needles) are mounted on the printed circuit board (PCB) in the probe card. The contact probes are mounted one by one by the hands. Recently, an array of the contact probe on the PCB is produced by the LIGA process in response to narrower semiconductor pitch length. The problem is that there are no methods to repair a wrong contact probe. Whole of the contact probes should be a waste owing to one wrong contact probe. We propose to replace a wrong contact probe with a good one using our apparatus. Experiments to remove a contact probe by the apparatus is carried out using the specimen of a mimic probe card, where a cantilever type contact probes are arranged with a pitch of 25 micrometers. Removal of the wrong contact probe is carried out by a non-contact discharge and a contact discharge using the apparatus. High voltage of about 1-2kV is applied after the work probe is moved to above the target contact probe for the non-contact discharge. While high voltage of about10kV is applied after the work probe is positioned in contact with the target contact probe for the contact discharge. The target contact probe is removed by both methods, though the neighboring contact probes are damaged. The latter method is hopeful for removal for repair of the probe card.
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