Wire sweep phenomenon overview by Ishikawa diagram

Wire sweep, the deflection of wires due to package encapsulation by molding compound, is one of the biggest concerns for the correct functionality of a device, due to the risk of crossover and shorting. The progressive greater complexity of the bonding diagrams is requiring a more stringent control on wire displacement due to resin flow, since a differential sweep of adjacent wires could be responsible of shorting even if the sweep is within specification. The objective of this paper is to provide an effective overview of the wire sweep phenomenon and the possible solutions. This text is structured following the Ishikawa method, more commonly known as fishbone diagram. This technique is often used in manufacturing and product development to identify the possible causes for an event or a problem, illustrate where the quality control issues might arise, and consequently determine corrective actions and resources allocation.