摘要 |
A fully-populated Pin Grid Array (PGA) is vacuum-chucked to a pedestal, without mechanical clamping. The pedestal includes a cylindrical shaft having a vacuum passageway extending its length, and a vacuum reservoir block mounted atop the shaft, and an alignment/fixture plate mounted atop the vacuum reservoir block. The alignment/fixture plate is provided with holes extending partially through the plate, at least about its periphery, for receiving the outermost rows/columns of pins of the PGA, while maintaining a vacuum seal. In one embodiment, a central portion of the alignment/fixture plate is provided with a large through-opening for receiving the remaining pins of the PGA. In another embodiment, the central portion of the alignment/fixture plate is provided with a plurality of individual through holes corresponding to the remaining pins of the PGA. In this manner, the PGA is held securely and well aligned within a wire bonder, while avoiding damaging the pins.
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