Application of focused ion beam lift‐out specimen preparation to TEM, SEM, STEM, AES and SIMS analysis

Abstract

Commercially available focused ion beam (FIB) workstations with spatial resolution of 5-7 nm can prepare specimens with excellent lateral resolution. This capability has been utilized extensively by the semiconductor industry to obtain materials characterization from continually smaller areas. The FIB has been adopted generally as a preparation tool for scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The ability to prepare site-specific specimens that can be removed from the bulk of a sample provides enhanced SEM and TEM analyses and new approaches for other analytical tools. Dedicated scanning transmission electron microscopy (STEM) can provide images through samples several micrometers thick. Auger electron spectroscopy (AES) can analyze with improved ability to identify a small particle. Secondary ion mass spectrometry (SIMS) can provide trace analysis at high mass resolution. Automatic operation of FIB workstations permits the creation of multiple lift-out samples without the presence of an operator.

Pin point depth profiling for unit device or several nano‐devices

“…Nowadays, the micro-sampling method is an indispensable technique for TEM sample preparation. 5 By using this method, a piece of the sample can be picked up from a bulk sample without destroying the structure of the sample of interest or/and cleaving the substrate. Therefore, the micro-sampling method enables shave-off depth profiling to be a pin point depth profiling.…”

Surface science analysis of GaAs photocathodes following sustained electron beam delivery

“…Sample preparation for TEM analysis of the strained superlattice structure was performed at North Carolina State University using a focused ion beam (FIB) milling and a lift-out technique to prepare the samples without damaging the superlattice structure [22]. To remove the depth cross section for TEM analysis, the GaAs is first protected by coating with an evaporative layer of gold and palladium.…”

Cryo‐snap: A simple modified freeze‐fracture method for SEM imaging of membrane cross‐sections

“…Mechanical cuts using sharp force devices (razor blades or knives) create compression, tearing, and localized heating which can severely distort the fine structures of the membrane. Relatively clean cross-sections may be obtained using special equipment such as a focused ion beam or an ultramicrotome [13,14]; however, these methods require laborious sample preparation and expensive equipment. A commonly used approach is the direct freeze fracture method, where the membrane sample is frozen in liquid nitrogen to make it brittle and quickly broken [11].…”