摘要 |
Socketable balls are mounted to a BGA package by first placing the balls into pockets or holes of a tray that are sized such that when the balls are inserted, an upper portion of the ball protrudes above a planar surface of the tray. A layer of a polymer material is then applied over the balls and a top area of each of the balls is exposed, and plated with solder. During the plating step the polymer provides a solder-tight seal against each of the balls such that, except for the top area, the rest of the surface area of the balls remains solder-free. The solder-plated top area of each of the balls is then bonded to the corresponding plurality of lands of the package by reflowing the solder to establish electrical contact therebetween.
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