Methods to Enable Fault Isolation on 2.5D Molded Interposer Packages

This article discusses the failure analysis challenges associated with large overmolded 2.5D packages and explains how laser decapsulation followed by microwave-induced plasma (MIP) spot etching removes overmold while keeping everything else intact. It also describes a defect isolation procedure in which the sample is analyzed in a large chamber environmental SEM with its ball grid array directly wired to an EBAC amplifier.