| 摘要 |
<p>The placement of solder 'balls' in a Ball Grid Array is accomplished by placing a solder strip (73) in contact with the top surface of the ball grid array carrier. The pulsing of a laser directed at the solder (74) in discrete positions permits the transfer of the solder to the gold dot (70), of the array of dots, on the carrier (71) in registry with the laser output (82) when activated. Selective solder placement is possible and increasingly higher throughput is achieved by the use of laser diode bars (80) or optical fiber fans to effect solder transfer to a plurality of dots of the array simultaneously. The use of a transparent strip (73) with a pattern of holes filled with solder paste (74) permits easy transfer of the solder to the gold dots or islands (70) on the carrier (71) in registry with laser beam.</p> |
