Contrast Mechanisms in Secondary Electron e-Beam-Induced Current (SEEBIC) Imaging

Abstract

Over the last few years, a new mode for imaging in the scanning transmission electron microscope (STEM) has gained attention as it permits the direct visualization of sample conductivity and electrical connectivity. When the electron beam (e-beam) is focused on the sample in the STEM, secondary electrons (SEs) are generated. If the sample is conductive and electrically connected to an amplifier, the SE current can be measured as a function of the e-beam position. This scenario is similar to the better-known scanning electron microscopy-based technique, electron beam-induced current imaging, except that the signal in the STEM is generated by the emission of SEs, hence the name secondary electron e-beam-induced current (SEEBIC), and in this case, the current flows in the opposite direction. Here, we provide a brief review of recent work in this area, examine the various contrast generation mechanisms associated with SEEBIC, and illustrate its use for the characterization of graphene nanoribbon devices.

Thermoelectric Limitations of Graphene Nanodevices at Ultrahigh Current Densities

“…(f–h) Adapted by permission from John Wiley and Sons: Small Methods (ref ( 31 )), copyright 2022. (j–l) Adapted from Oxford University Press: Microscopy and Microanalysis ref ( 34 ), copyright 2022.…”

“…Voltage applied to the device before acquiring image (c,d,e,f,g) was 3.3, 4, 4.6, 4.8, and 4.9 V, respectively. (g) Adapted from Oxford University Press: Microscopy and Microanalysis ref ( 34 ), copyright 2022.…”

High-Throughput Morphological Chirality Quantification of Twisted and Wrinkled Gold Nanorods

“…Previous studies have demonstrated the use of MEMS devices with electron-transparent Si 3 N 4 windows and lithographically patterned electrodes to perform SEEBIC experiments. 34,44,45 It was demonstrated that the Si 3 N 4 membrane yields sufficient conductivity for the required charge transport. 34 Alternatively, conventional TEM grids can also be used for SEEBIC experiments.…”

“…Previous studies have demonstrated the use of MEMS devices with electron-transparent Si 3 N 4 windows and lithographically patterned electrodes to perform SEEBIC experiments. ,, It was demonstrated that the Si 3 N 4 membrane yields sufficient conductivity for the required charge transport . Alternatively, conventional TEM grids can also be used for SEEBIC experiments. , We used herein a sample carrier based on a 0.6-mm thick FR4 printed circuit board, designed to fit in a DENS Solutions Wildfire heating holder, which allows the use of a conventional copper TEM grid as a sample support …”

Secondary electron induced current in scanning transmission electron microscopy: an alternative way to visualize the morphology of nanoparticles

“…Later, it was demonstrated that lattice-resolution imaging is feasible, as well as resistive contrast imaging, allowing visualization of resistive grain boundaries in multilayer ceramic BaTiO 3 capacitors . A series of papers by Dyck et al have been issued, focusing on charge carrier transport in graphene nanodevices and the use of SEEBIC for device failure analysis. − SEEBIC allowed a clear distinction between single and multilayer graphene and visualization of cracks in graphene sheets.…”