Detailed Electron Energy Loss Spectroscopy (EELS) Microanalysis of Data Collected Under Semi-Angle Less Than Both Plasmon Cutoff Angle and Incident Beam Convergence Semi-Angle

TL;DR

This paper introduces a detailed numerical analysis method for electron energy loss spectroscopy (EELS) data collected under specific semi-angle conditions, enabling comprehensive physical parameter extraction from a single spectrum.

Contribution

It presents a new numerical technique compatible with semi-angle conditions less than the plasmon cutoff angle, allowing for more complete analysis of EELS data including incident beam convergence corrections.

Findings

Successfully extracted multiple physical parameters from a single EELS spectrum.

Compared results with existing non-EELS techniques showing good agreement.

Demonstrated the method on silicon nitride EELS data.

Abstract

In previous work a different and powerful, analytical, technique was used to get data, such as the absolute atom concentration (AAC), specimen thickness etc., from public domain boron nitride EELS spectrum collected under a collection semi-angle, $\beta$, less than the plasmon cutoff angle, $\theta_{c}$, but large relative to incident beam convergence, $\alpha$. Here, seeking for some completeness, another, numerical, technique usable together with, also, $\beta < \theta_{c}$ is described in minute detail and applied to data obtained with $\beta/\alpha < 2$, so necessitating incident beam convergence-related corrections. A lot of experimental physical parameters all fully relevant to one another are produced from a single EELS spectrum. Of public domain silicon nitride, Si$_{3}$N$_{4}$, EELS spectrum used. Comparison between results producible by the two $\beta<\theta_{c}$-related techniques made. Results range from parameters such as AAC, density, plasmon critical vector, plasmon dispersion coefficient, Fermi energy to specimen thickness. Results were obtained using version 5 of eelsMicr program and compared with existing results obtained using non EELS techniques.