| 摘要 |
A method and apparatus enables the securing of balls to ball grid array electronic components. A component having a surface with rows and columns of electrical contact pads is removed from a printed circuit board for rework. Excess solder is removed from the pads and the surface is pressed against a stencil having a pattern of holes corresponding to the component contact pad pattern. The holes are filled with a paste continuing flux and solder particles. The assembly is heated to melt the solder particles, which agglomerate into generally spherical balls bonded to the contact pads. The assembly is cooled, the stencil is removed, the component is cleaned and is ready for reuse. Preferably, the stencil is formed from a material that bows in one direction when heated, so that when the stencil is held against the pad array surface and heated, bowing forces will very tightly press the stencil against the surface, preventing molten solder from migrating between surface and stencil.
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