Focused ion beam sample preparation for atom probe tomography

Abstract

Atom Probe (AP) tomography is maturing into a routine method for the atomic resolution compositional analysis of metals, semiconductors and some polymers. This is often combined with a Transmission Electron Microscope (TEM) analysis of the same region of interest. The Focused Ion Beam (FIB) microscope has evolved as an essential tool for site and orientation specific sample preparation for such analysis. We review existing FIB-based AP/TEM sample preparation techniques and present a number of innovative approaches to specimen preparation illustrated with examples including a silicon-on-insulator semiconductor device, a twin boundary in a Cu-Bi alloy and a crystalline precipitate phase in a bulk metallic glass.