In this technique, solder balls and flux are preloaded into a specialty pick and place machine designed to place solder balls. The machine is loaded with the proper paste flux and correctly-sized and alloy solder balls. After programming a temperature-controlled solder flux dispenser, a controlled volume of paste flux is dispensed onto each of the component pads. This is followed by the pick and place machine precisely placing the balls into the flux. Tooling for the machine is made to hold an array of solder balls. The machine needs to be loaded with enough of the correct solder balls as well as being loaded with the proper flux paste. The machine will continue to run as long as these inputs are being properly fed.
The process below is generic in nature and is adopted to the customer specifications, lot size and the type of component being reballed
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The high volume reballing method is used when a large number of the same part pattern device need to be reballed. When there are smaller package components this is a preferred technique as the machine can continue to run with a machine operator as opposed to a highly skilled rework technician. Other reballing process considerations and analytical testing can be found here.