Cryo-FIB for TEM investigation of soft matter and beam sensitive energy materials

Abstract

Primarily driven by structural biology, the rapid advances in cryogenic electron microscopy (cryo-EM) techniques are now being adopted and applied by materials scientists. Samples that inherently have electron transparency can be rapidly frozen (vitrified) in amorphous ice and imaged directly on a cryogenic transmission electron microscopy (cryo-TEM), however this is not the case for many important materials systems, which can consist of layered structures, embedded architectures, or be contained within a device. Cryogenic focused ion beam (cryo-FIB) lift-out procedures have recently been developed to extract intact regions and interfaces of interest, that can then be thinned to electron transparency and transferred to the cryo-TEM for characterization. Several detailed studies have been reported demonstrating the cryo-FIB lift-out procedure, however due to its relative infancy in materials science improvements are still required to ensure the technique becomes more accessible and routinely successful. Here, we review recent results on the preparation of cryo-TEM lamellae using cryo-FIB and show that the technique is broadly applicable to a range of soft matter and beam sensitive energy materials. We then present a tutorial that can guide the materials scientist through the cryo-FIB lift-out process, highlighting recent methodological advances that address the most common failure points of the technique, such as needle attachment, lift-out and transfer, and final thinning.

Nanoscale Polycyclosiloxane Interlayer for Enhanced Lithium Plating on Copper

“…For cryogenic scanning transmission electron microscopy (cryo-STEM) imaging, first, a cryogenic TEM lamella was prepared using previously reported techniques . This was carried out on a Scios 2 Dual Beam SEM/FIB instrument with a Leica VCT cryogenic stage installed.…”

Atomic-level imaging of beam-sensitive COFs and MOFs by low-dose electron microscopy

“…138,139 Cryo-FIB has also been applied to the processing of metals and their alloys, 140 solid-liquid interfaces and reactive materials, 141 solar cells, 142 and more. 143,144 Recently, pioneering work on the application of cryo-FIB in ultra-sensitive materials, MOFs and hybrid halide perovskites was reported (Fig. 9a and b).…”