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.


Solar Cell Buss Bar to Connector Box Defects - Application Note 902


Sample & Method

In the image the echoes from the ultrasonic transducer were gated on the interface between the silicon stack and the connector box on a large solar panel. The large metallic buss bar in the center of the image is also captured.


The strongest signals were reflected by the partial white rings around the connector box and sections along the large buss bar. These areas are delaminations between the silicon stack and the various interfaces. The darker grey areas along the center of the buss bar (ribbon) are representative of a good but degrading bond between the cell and the buss bar.