Dye & Pry (DPA Technique)
Dye and Pry is a destructive technique for inspection of surface mount component solder joints. It is useful for detecting fractures in the solder ball, ball to pad interfaces or lifting of the pads from the PCB. The analysis utilizes a penetrating dye under vacuum to force the dye into micro-cracks or opens in the solder joints or printed circuit board (PCB). The sample is then allowed to dry in an oven so that there is no smearing of the dye during the mechanical prying of the device from the board. The device and PCB are then inspected for the presence of dye within the solder joint or under pads. The process can determine complete or partial opens. Characterization of the failed pad/ball interface can be subsequently examined using optical microscopy or SEM and can be used to track functional information or open circuits on ball grid arrays.