Introduction

Focused ion beam (FIB) and focused ion beam/scanning electron microscope (FIB/SEM) systems are invaluable tools for the preparation of specimens for physical and chemical analysis. Both systems are routinely used to prepare site-specific specimens for transmission electron microscopy (TEM), SEM and FIB microscopy of a wide range of materials including polymers [1], steels [2, 3], surface coatings [4, 5], catalysts [6], and semiconductors [7–11]. These systems are also used for the preparation of specimens for other analytical techniques such as Auger [12] and atom probe (AP) field ion microscopy [13].

The increase in use of FIB and FIB/SEM systems during the 1990s for the preparation of specimens for material analysis is due to the significant advantages they offer over other methods such as broad ion beam (BIB) milling, electro-polishing, or mechanical polishing. The main advantage is that the cross sections and TEM lamellae can be prepared to within 50 nm of a feature or region of interest (ROI), making it possible to analyze specific defects, phases, or interfaces. Such positional accuracy is very difficult to achieve using other sample preparation techniques. Although polishing can be used to prepare SEM cross sections to within 500 nm of a feature, this is a time consuming process in which the sample has to be repeatedly imaged (either using an optical microscope or an SEM) to ensure the feature is not polished through.