Analysis of crystal defects by scanning transmission electron microscopy (STEM) in a modern scanning electron microscope

Abstract

Dislocations and stacking faults are important crystal defects, because they strongly influence material properties. As of now, transmission electron microscopy (TEM) is the most frequently used technique to study the properties of single dislocations and stacking faults. Specifically, the Burgers vector b of dislocations or displacement vector R of stacking faults can be determined on the basis of the g·b = n (g·R = n) criterion by setting up different two-beam diffraction conditions with an imaging vector g. Based on the reciprocity theorem, scanning transmission electron microscopy (STEM) can also be applied for defect characterization, but has been less frequently used up to now. In this work, we demonstrate g·b = n (g·R = n) analyses of dislocations and stacking faults in GaN by STEM imaging in a scanning electron microscope. The instrument is equipped with a STEM detector, double-tilt TEM specimen holder, and a charge-coupled-device camera for the acquisition of on-axis diffraction patterns. The latter two accessories are mandatory to control the specimen orientation, which has not been possible before in a scanning electron microscope. which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Nanocomposite‐Seeded Epitaxial Growth of Single‐Domain Lithium Niobate Thin Films for Surface Acoustic Wave Devices

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Imaging of polymer:fullerene bulk-heterojunctions in a scanning electron microscope: methodology aspects and nanomorphology by correlative SEM and STEM

“…Despite of these advantages, low-energy STEM (≤ 30 keV) in a scanning electron microscope (also denoted as STEM-in-SEM) has not been extensively exploited up to now and only few methodological studies were published [9][10][11]. More recent work comprises, e.g., nanoparticle characterization [12,13], dislocations analysis and manipulation [14][15][16][17], composition quantification [18], beam broadening [19,20], transmission electron microscopy (TEM) specimen thickness determination [21] as well as reduced delocalization and negligible Cherenkov losses in electron energy loss spectroscopy [22]. Low-energy STEM is also well suited to study weakly scattering and beam-sensitive (knock-on damage) materials such as bulk-heterojunction (BHJ) absorber layers of organic solar cells [23].…”

Versatile application of a modern scanning electron microscope for materials characterization

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