An improved FIB sample preparation technique for site-specific plan-view specimens: A new cutting geometry

Abstract

Focused ion beam (FIB) sample preparation technique in plan-view geometry allows direct correlations of the atomic structure study via transmission electron microscopy with micrometer-scale property measurements. However, one main technical difficulty is that a large amount of material must be removed underneath the specimen. Furthermore, directly monitoring the milling process is difficult unless very large material volumes surrounding the TEM specimen site are removed. In this paper, a new cutting geometry is introduced for FIB lift-out sample preparation with plan-view geometry. Firstly, an "isolated" cuboid shaped specimen is cut out, leaving a "bridge" connecting it with the bulk material. Subsequently the two long sides of the "isolated" cuboid are wedged, forming a triangular prism shape. A micromanipulator needle is used for in-situ transfer of the specimen to a FIB TEM grid, which has been mounted parallel with the specimen surface using a simple custom-made sample slit. Finally, the grid is transferred to the standard FIB grid holder for final thinning with standard procedures. This new cutting geometry provides clear viewing angles for monitoring the milling process, which solves the difficulty of judging whether the specimen has been entirely detached from the bulk material, with the least possible damage to the surrounding materials. With an improved success rate and efficiency, this plan-view FIB lift-out specimen preparation technique should have a wide application for material science.

Transmission Electron Microscopy Sample Preparation of INCONEL 738 Nickel-Base Superalloy

“…Therefore, ion beam milling TEM sample preparation can be considered as a rough method for INCONEL alloy surface microstructure study. Focused ion beam technique have been developed to overcome extensive surface artifact develop by traditional bulk ion beam milling technique [18]. However, focused ion beam milling has its own limitation.…”

Do the latest scanning electron microscopes with a variety of analytical and imaging techniques provide us with realistic images and compositions?

“…Earlier work showed that the removal of material behind the region of interest could improve the quality of the EDS image. [14][15][16][17] Figure 1 shows how the lines within the interaction volume delineate the regions where the effect indicated predominates. For example, only X-rays emerge from the sample from the deeper parts of the sample and the depth of this interaction volume can be calculated and simulated with a Monte Carlo simulation.…”

FIB lift-out of conducting ferroelectric domain walls in hexagonal manganites

“…For SPM characterization the lamella is then lifted out using an EasyLift EX lift-out needle. Using a combination of motorized needle rotation and a pre-tilt stub, it is possible to put down the lamella in a single step, i.e., without any transfer steps as commonly used in planview lamella preparation (which requires a similar 90 • rotation between plan-view and cross-section geometry 36 ). This process is illustrated in Figure 2: The needle is attached [ Figure 2 700 nm and polished with the 30 kV beam at a glancing angle of 3 • -5…”