Evaluation of Solder Bonds in a Silicon Flip Chip Device

Abstract

<p>Recently we adapted two nondestructive testing techniques for the evaluation of electrical connections between a silicon device wafer and an inverted silicon interconnect chip. We used a focused acoustic microscope to check the mechanical quality of the connections, and a photothermal probe to measure their electrical conductivity. With the combination of these two techniques, we can differentiate between good bonds, partial disbonds, and complete open circuits. We can also determine the type of disbond.</p>