Non-destructive analysis on flip chip package with TDR (time domain reflectometry) and SQUID (superconducting quantum interference device)

With increasing applications of thin multi-layer flip chip packages with complex interweaving layout, the difficulties and ineffectiveness of fault isolation with current nondestructive techniques such as RTX (real time X-ray) and SAM (scanning acoustic microscopy) have increased significantly. TDR (time domain reflectometry) and scanning SQUID (superconducting quantum interference device) as new nondestructive techniques for fault isolation have been developed to overcome some of the difficulties. In this paper, the methodology and application of TDR and SQUID on open and short failure isolations in flip chip packages are presented. The analysis procedure and results on both fault isolations, as well as physical analyses to further inspect the root cause, have also been discussed in detail.