Delaminations in Substrate

Pictured

Time Domain Imaging (TDI)™
Utilizes an echo (amplitude & polarity) arrival ‘time’ as a reference, such as standard A-Scan, B-Scan and C-Mode type images.

Delaminations in Substrate

Plastic BGA - MC to Substrate Delamination - Application Note 2596

Delaminations in Substrate

Sample & Method

In the image the echoes from the ultrasonic C-SAM transducer were gated on the interface between the molding compound and the substrate.

Result

The strongest signals were reflected by the large white area at right. This area is a large delamination between the molding compound and the substrate. Significantly, the delamination includes the area of the wire bonds, meaning that the wires are subject to mechanical movement as the result of thermal cycling or vibration.