Dye & Pry

Dye and Pry involves cleaning a sample to remove debris and flux around solder, then exposing it to a red dye by immersion.  The sample is then exposed to either vacuum or pressure to ensure the dye penetrates into all cracks, separations and surfaces with exposure to the outside of the device.

BGA on PCB as received	BGA Dyed

The parts are then baked in an oven until fully dry. The ink must be fully dried to avoid smearing later.  The device is then separated by prying or flexing of the PCB.  The interfaces now separated are inspected optically.  Failure sites are imaged and identified.

BGA Pryed PCB side	BGA pryed component side

For PQFPs and TSOPs on a PCB the areas of interest are the lead fingers.  The ink gets in where there are cracks in the solder or failure to reflow the solder.  These are areas of weak bonding and likely reliability failures.  The silver colored areas are where the ink was unable to ingress showing good bonding.

PQFP as received	PQFP dyed
PQFP pryed device side	PQFP PCB side
TSOP on PCB as received	TSOP dyed
TSOP PCB side pryed	TSOP component side dyed

Dye and Pry is an excellent way to inspect a large number of bonds (leads, solder ball, seals..) at one time.