Analysis of the Be KLL Auger Transition on Beryllium and Beryllium Oxide by AES

Abstract

As-received beryllium, beryllium scribed in vacuum and beryllium oxide were analysed by Auger Electron Spectroscopy. As-received beryllium was analysed at low and high take off angles. Spectra produced demonstrate the change in the KLL structure with increasing oxygen concentration. Survey spectra as well as high resolution Be KLL and O KLL transitions were collected and are presented. INTRODUCTIONAs a continuation of the previous XPS investigation on beryllium, the KLL Auger transition of beryllium has been examined. It is shown herein that the beryllium metal signal is highly attenuated by the thin surface oxide layer, of $3 nm, due to the low kinetic energy of the transition. Upon removal of this oxide by scribing the metal surface in vacuum a striking increase in the beryllium signal is obtained. Little current literature is available regarding the Auger analysis of beryllium or beryllium compounds. Some of the most recent work has used Auger to monitor the oxidation of beryllium for the investigation of the electronic band structure of beryllium (Ref. 1) and a number of authors in the past have studied the KLL Auger transition in both beryllium (Refs. 2-4) and beryllium oxide (Refs. 1-5).The earliest work on clean beryllium observed two peaks in the derivative spectrum which were identified as 1s2s2s and 1s2p2p transitions at 92 eV and 104 eV respectively (Ref. 2). Another study confirmed the presence of a large sharp peak at 104.5 eV however no peak was observed at 92 eV. In addition to the large peak at 104.5 eV two small peaks at 84 and 60 eV were observed which were believed to be first and second order plasmon losses of the main peak (Ref. 3). Oxidation of the beryllium surface leads to formation of a strong peak at 94 eV and weaker satellites at 85, 77 and 66 eV (Ref. 3). It is concluded that clean beryllium has a large Auger peak at 104.5 eV and beryllium oxide at 94 eV. Later work confirmed that no peak is observed at 92 eV on clean, oxide free, beryllium, with the main peak position at $104 eV (Ref. 4). Beryllium oxide has also been confirmed to show a main peak at 94 eV and three satellites with positions approximately 87, 77 and 67 eV (Ref. 5).The main peak in BeO was confirmed to shift by $10 eV from that of Be (Refs. 1 and 5), the main peak at 95 eV and the satellite at 86 eV originate from the 1s2p2p transitions involving electrons from the top and bottom of the p-band respectively. The satellite at 78 eV is believed to be due to the 1s2p2s transition and the satellite at 68 eV is thought to be an energy loss feature (Ref. 5).In this work spectra are presented that show the main Auger transition for beryllium and beryllium oxide. The beryllium metal differential spectrum shows the primary peak at 108.8 eV together with a loss satellite at 91 eV. The native oxide differential spectrum contains the metal component at 108.3 eV, the main oxide component at 97 eV as well as a number of satellites at 88.5, 81 and 70 eV. The spectrum of native beryllium oxide film was acquired by tilting the sample ...

Characterization of Carbide Particles in S-65 Beryllium by Scanning Kelvin Probe Force Microscopy

“…10, which shows a significant reduction in the intensity of the carbide peak component ∼100 eV on the shoulder of the oxide peak component ∼95 eV. 25 The reducing potential of the carbide particles as the humidity increases suggests that the activity of the particles reduces with the increase in the oxide layer thickness, in agreement with results from previous SKPFM analysis. 11 By comparing previous SKPFM analysis of second phase particles in S-65 beryllium billet and bar samples to the results obtained in this work it becomes apparent that the carbide particles have the highest Volta potential of all the second phase particle types except for alumina type particles in bar grade beryllium.…”

The electron spectra of beryllium and beryllium oxide: an XPS, X‐AES and AES study

“…Sample charging of BeO in AES was overcome by tilting the sample and using a low beam energy. All spectra and raw data from this investigation have been published in the archival journal Surface Science Spectra …”

The chemical state plot for beryllium compounds

“…Beryllium carbide is a good insulator, and so, the sample was tilted to a near vertical 80° from its usual horizontal analysis position; the primary beam energy was also reduced from 10 to 3 kV. The same analysis conditions have been used for the study of bulk beryllium oxide . Beryllium nitride inclusions were found to be good conductors showing no signs of charging during imaging, and so the spectra were believed to be free from sample charging.…”

“…The same analysis conditions have been used for the study of bulk beryllium oxide. [6] Beryllium nitride inclusions were found to be good conductors showing no signs of charging during imaging, and so the spectra were believed to be free from sample charging. The signal to noise for the oxide and carbide spectra is significantly improved compared with the metal and the nitride spectra.…”