| 摘要 |
A method and apparatus for handling and positioning half plated balls for socket application in ball grid array packages. The half plated balls, comprising a first side adapted to be soldered and a second side adapted to establish reliable solderless electrical contact, are embedded in a soft foil, with a common orientation. The soft foil is positioned on a clam-receiving tool and a vacuumed caved cover clam is fitted on the balls and then pushed to cut and separate the polymer sheet from the copper ball surface. The vacuumed caved cover clam is then lifted with the oriented copper balls entrapped inside and the vacuumed caved cover clam places the entrapped balls on the laminate pads, with a deposit of low melt alloy. The air vacuum is deactivated and the cover is lifted, leaving the balls positioned on the pads while the soldering process is initiated and solder joints are formed to fix the balls.
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