Quantitative material analysis using secondary electron energy spectromicroscopy

Abstract

This paper demonstrates how secondary electron energy spectroscopy (SEES) performed inside a scanning electron microscope (SEM) can be used to map sample atomic number and acquire bulk valence band density of states (DOS) information at low primary beam voltages. The technique uses an electron energy analyser attachment to detect small changes in the shape of the scattered secondary electron (SE) spectrum and extract out fine structure features from it. Close agreement between experimental and theoretical bulk valance band DOS distributions was obtained for six different test samples, where the normalised root mean square deviation ranged from 2.7 to 6.7%. High accuracy levels of this kind do not appear to have been reported before. The results presented in this paper point towards SEES becoming a quantitative material analysis companion tool for low voltage scanning electron microscopy (LVSEM) and providing new applications for Scanning Auger Microscopy (SAM) instruments.

Carbon Capture Potential in Lime Modified Kaolin Clay

“…5. It is known that the use of SEM secondary electron images (SEI) combined with energy dispersion analysis (EDA) is primarily an imaging method and not a fully quantitative approach [17]. It is difficult to identify CaCO unambiguously using this approach.…”

Monitoring Carbon in Electron and Ion Beam Deposition within FIB-SEM

“…The signal signature for this form of contamination is greatly reduced as the FIB window is created, and as post FIB SES indicate at the time points, it is observed that this contamination does start to return to the surface of the materials as the sample undergoes conventional SEM imaging. This finding revealed that as well as the ability of SES to monitor ACC, Plasma FIB Xe exposure has the capability to remove carbon contamination from the surface of Ti without the requirement for chemical surface treatments [ 23 ]. The removal of carbon contamination is seen as an advantage for IBID fabrication, notably for nanoconductors to improve the conductivity of the deposited material and to increase the tensile elasticity of FIB fabrication microstructures [ 17 ].…”

“…The ability to monitor different forms of carbon contamination during the deposition process is still yet to be established. The most obvious reason for this is a lack of suitable characterisation tools is the combination of multiple requirements: high surface sensitivity (akin to X-ray photoelectron spectroscopy (XPS), high spatial resolution (akin to Auger electron spectroscopy) [ 21 ], and the ability to identify the carbon bonding present using low beam energies (reducing sample modification) without the need for an Ultra High Vacuum (UHV) [ 22 , 23 ]. All of these requirements may be fulfilled by Secondary Electron (SE) spectroscopy.…”

Dynamical imaging of local photovoltage at semiconductor surface by photo-assisted ultrafast scanning electron microscopy

“…These contrast modulations originate from the photoexcitation of local excess charge carrier distributions, which affect the configuration of surface states and the yield of SE emission. A less considered effect is that this change in charge distribution modifies the electric field outside the surface too, which in turn dynamically changes the SE collection in the SEM [1,2,4,5,6]. Both mechanisms, the changes in emission yield and in collection efficiency, contribute to the 2D dynamical SE patterns.…”