Flip-chip package soft failure analysis and case studies using time domain reflectometry

Abstract

This article describes how time domain reflectometry (TDR) enhances the capability of package-level fault isolation on resistive open, which is challenging using conventional methods, for flip-chip microprocessors. TDR successfully isolated the resistive open that caused functional failure; dual-beam focused ion beam (DB-FIB) confirmed TDR's isolation. Several cases studies for package/die failure isolation using TDR are also discussed.