Fault localisation of defects using Electro Optical Terahertz Pulse Reflectometry and 3D EM modelling with Virtual Known Good Device

Abstract

A methodology for electronic non-destructive failure analysis of 3D-ICs is presented. The method is centred on the Electro Optical Terahertz Pulse Reflectometry technique. Through use of 3D Electromagnetic modelling, a Virtual Known Good Device can be established allowing the means to locate faults in a 3D package design. Measured voltage waveforms generated using the Electro Optical Terahertz Pulse Reflectometry technique are presented for a BGA package with an open defect. Measurements are in good agreement with 3D EM simulation results for the same scenario demonstrating the potential of this technique to locate faults quickly and accurately.