Christopher F. Mallinson

Next Generation Device Grade Silicon-Germanium on Insulator

High quality single crystal silicon-germanium-on-insulator has the potential to facilitate the next generation of photonic and electronic devices. Using a rapid melt growth technique we engineer tailored single crystal silicon-germanium-on-insulator structures with near constant composition over large areas. The proposed structures avoid the problem of laterally graded SiGe compositions, caused by preferential Si rich solid formation, encountered in straight SiGe wires by providing radiating elements distributed along the structures. This method enables the fabrication of multiple single crystal silicon-germanium-on-insulator layers of different compositions, on the same Si wafer, using only a single deposition process and a single anneal process, simply by modifying the structural design and/or the anneal temperature. This facilitates a host of device designs, within a relatively simple growth environment, as compared to the complexities of other methods, and also offers flexibility in device designs within that growth environment.

Comparison of Ar+ monoatomic and cluster ion sputtering of Ta2O5 at different ion energies, by XPS: Part 1 - Monoatomic ions

A standard 30 nm thick Ta2O5 oxide layer grown on Ta was examined by XPS after Ar+ ion bombardment at ion energies of 200 eV, 500 eV, and 3 keV. The reduction of Ta2O5, resulting from the preferential sputtering of oxygen after ion beam bombardment at different energies has been investigated. Survey spectra, C 1s, Ta 4f and O 1s spectra are presented for each profile at three stages: native surface, after reaching the steady-state oxide composition, and from the underlying metal substrate. Reducing the Ar+ energy from 3 keV to 200 eV makes no substantial difference in the degree of Ta2O5 reduction observed following ion bombardment.

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

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.

Beryllium and Beryllium Oxide by XPS

As received beryllium and beryllium oxide, purchased from Goodfellow, were analysed by x-ray photoelectron spectroscopy. Survey spectra, high resolution spectra of elemental peaks and beryllium Auger transitions were collected and are presented. The binding energy of metallic beryllium 1s peak and the beryllium oxide 1s peak were found to be 110.5 and 113.4 eV respectively. The kinetic energy of the main metal and oxide KVV Auger transitions were found to be 103.5 and 95.5 eV respectively.

Analysis of the Be KLL Auger transition of beryllium nitride and beryllium carbide by AES

Secondary phase particles of beryllium nitride and beryllium carbide in beryllium were analyzed by Auger Electron Spectroscopy. Survey spectra as well as high resolution Be KLL, N KLL and C KLL transitions were collected and are presented. The primary beryllium KLL Auger transitions for the nitride and carbide were recorded at 96.7 and 100.4 eV respectively. The homogeneity and composition of the secondary phase particles was confirmed by energy dispersive x-ray spectroscopy.

XPS Examination of the Oxide Layer Formed on Kovar Following Pre-Oxidation

Kovar (Fe-29 Ni-17 Co wt%) is widely used in electrical components. For applications such as feed-throughs there is a requirement to join it to glass, forming a glass-to-metal seal. A controlled thickness, well adhered, oxide is desired on the Kovar to form a strong bond. The oxides formed on Kovar pre-oxidized, at 700 and 800 °C for ten min, have been analyzed. Each sample showed the presence of Fe2O3, CoO and NiO. XPS survey spectra and high resolution spectra were collected and are presented.

Analysis of the Li KLL Auger Transition on Freshly Exposed Lithium and Lithium Surface Oxide by AES

Lithium scribed in vacuum and a particle of lithium oxide were analysed by AES and lithium metal exposed to atmosphere for <1 min was analysed by XPS. The oxide particle embedded in the host metal was analysed at low and high take off angles. AES spectra acquired demonstrate the change in the KLL structure with increasing oxygen concentration. Survey spectra as well as high resolution narrow spectra were acquired and are presented. The presence of lithium carbonate, together with the oxide, formed in air, was confirmed by XPS as it is not easily resolvable using AES.

XPS examination of the native oxide layer on Kovar using aluminium, magnesium and silver x-ray sources

Kovar, a common glass-to-metal sealing alloy, has been analysed by XPS. Monochromatic aluminium and silver sources as well as an achromatic magnesium x-ray source have been utilised to demonstrate the increased clarity of spectra that can be obtained through the use of each x-ray source in the analysis of a transition metal rich alloy.

Analysis of Silicon Germanium Standards for the Quantification of SiGe Microelectronic Devices Using AES

Four samples of well-defined silicon-germanium alloys were used as standards for calibration purposes to allow accurate quantification of silicon-germanium-on-insulator (SGOI) microelectronic devices using Auger electron spectroscopy. Narrow Si KLL and the Ge LMM, high resolution Si KL2,3L2,3 and Ge L3M4,5M4,5 together with survey spectra were collected and are presented from each sample. A matrix effect was observed for silicon in germanium and calculated as 0.85 and 0.95 for the Ge77.5Si22.5 and Ge52.4Si47.6 alloys respectively.

Excitation of XPS spectra from nanoscaled particles by local generation of x-rays

In preliminary work, the authors have shown that use of an aluminum substrate to support a distribution of copper particles enables their characteristic photoelectrons to be observed within the Auger electron spectrum generated by an incident electron beam. This observation raises the possibility of the use of chemical shifts and the corresponding Auger parameter to identify the chemical states present on the surface of individual submicrometer particles within a mixture. In this context, the technique has an advantage in that, unlike conventional Auger electron spectroscopy, the electron beam does not dwell on the particle but on the substrate adjacent to it. Given the importance, for both medical and toxicological reasons, of the surface composition of such particles, the authors have continued to explore the potential of this development. In this contribution, the authors show that proximal excitation of x-rays is equally successful with magnesium substrates. In some regions of the x-ray photoelectron ...