The Application of Chemical Etching to the Failure Analysis of Semiconductor Devices (Experimental). Volume 2: Phase 2 Report

摘要

The development of an etchant or series of etchants that can be used in the failure analysis of semiconductor devices in order to remove passivating overglazes without causing damage to underlying metal or thermal oxide layers was studied. Various GaAs LED's were decapsulted, the chips removed, and sectioned. The exposed junctions were delineated with dilute nitric acid/iron. Silicon devices were also decapsulated. The nitride passivation layer was removed using and etchant specially formulated to prevent any damage occurring to the underlying metallization. The devices were operated after the nitride removal and voltage contrast scanning electron micrographs of them were produced. The metal layers were removed in a variety of etchants; no satisfactory way was found to remove aluminum from titanium.