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Scanning transmission electron microscopy (STEM) imaging has traditionally relied on (mostly) incoherent imaging using electrons scattered to high angles [1,2]. This gives strong contrast for imaging heavier atoms, but is only an incomplete technique for in ferroelectrics or polar-ordered functional oxides, since the oxygens are invisible in the presence of the dominant scattering from the heavy cations. In recent years, however, there has been a resurgence in the use of low angle scattered electrons using modes like annular bright field imaging [3] and standard bright field imaging [4,5]. This allows the direct imaging of oxygen atoms, which can be used for a full quantification of the local polarization [5], as has previously been performed using negative CS imaging using high resolution TEM [6].

Z-contrast scanning transmission electron microscope (STEM) observations of a quasicrystal have provided significant insights into the veiled structural details [1]; however, the resolution is still not sufficient to reveal a total structure including relatively low-Z atoms. To investigate further details in particular on local disorders, we here use a spherical aberration (Cs) corrected 300kV-STEM (VG-HB603U with Nion corrector, at ORNL), which has in fact achieved a sub-A resolution [2].

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

Cryo-scanning electron microscopy (cryo-SEM) and cryo-transmission electron microscopy (cryo- TEM), in conjunctions with rheological measurements, light and confocal microscopy, x-ray scattering, and solid state NMR, are used to characterize sodium stearate (NaSt) crystals dispersed in waterpropylene glycol (PG) mixtures at macroscopic, microscopic, molecular, and atomic levels. NaSt is a surface-active, structural agent in household and personal cleaning products, including deodorant sticks and soap bars. A better structural characterization of NaSt/PG/water systems has practical importance in personal care and cosmetic industries. NaSt crystals and other soap crystal morphologies have been studied by the TEM/replica technique. However, the replicas were made of the residue after the original sample or its aqueous dilution were dried, and the original structure may have been lost during drying. Cryo-SEM was not used to study NaSt crystals because of its lower resolution and because the crystals are highly susceptible to radiation damage by electron beam.

Secondary ion mass spectrometry (SIMS) is based upon the energetic ion bombardment of surfaces resulting in in the emission of sputtered particles, including both atomic and molecular ions. The use of mass spectrometric detection provides a highly versatile and sensitive tool for surface and thin film microanalysis. The scope of the technique includes a diversity of analysis modes including:1.Elemental Depth Profiling (dynamic SIMS),2.Laterally Resolved Imaging (ion microprobe or ion microscope analysis),3.Image Depth Profiling (combination of modes 1 and 2 providing 3-D images),4.Molecular Monolayer Analysis and Imaging (static SIMS),5.Sputtered Neutral Mass Spectrometry (post-ionization).Much of the early work in dynamic SIMS centered on depth profiling and imaging techniques, with an emphasis on applications to electronic materials. SIMS has made extensive contributions to semiconductor materials science since the 1960's, including the development of new devices and processes, and in failure analysis.

A great deal can be learned about integrated circuits (ICs) and microelectronic structures simply by imaging them in a focused ion beam (FIB) system. FIB systems have evolved during the past decade from something of a curiosity to absolutely essential tools for microelectronics design verification and failure analysis. FIB system capabilities include localized material removal, localized deposition of conductors and insulators, and imaging. A major commercial driver for FIB systems is their usefulness in the design debugging cycle by (1) rewiring ICs quickly to test design changes and (2) making connection to deep conductors to facilitate electrical probing of complex ICs. FIB milling is also used for making precision cross sections and for TEM sample preparation of microelectronic structures for failure analysis and yield enhancement applications.