Fast Atom Bombardment Secondary Ion Research Articles

Surface chemical studies of anodically oxidised aluminium membranes

X-ray photoelectron spectroscopy (XPS) and fast atom bombardment secondary ion mass spectrometry (FAB-SIMS) have been used to study the surfaces of inorganic microfiltration membranes produced by controlled removal of anodic films formed on aluminium in phosphoric and oxalic acid electrolytes. The results are compared with those of similar analyses of membranes produced from anodic films formed in mixed oxalic/phosphoric acid electrolyte. Both techniques established that phosphates were concentrated on the surface of membranes formed in phosphoric acid and oxalic/phosphoric acid and that oxalate ions were present on the surfaces of membranes formed in oxalic acid. The low intensity of the AlO - x fragments implies that all of the aluminium ions in the surface are coordinated to phosphates or oxalates. However, any differences its the chemical state of the aluminium on the different membranes were not detectable by either technique.

The reactions of oxidised aluminium surfaces with lubricant additives and related compounds

To improve the understanding of the role of lubricants in metal deformation processes, FABSIMS (fast atom bombardment secondary ion mass spectroscopy) and RAIRS (reflection absorption infrared spectroscopy) were used to study the chemical interaction of carboxylic acids on oxidised aluminium surfaces. Both techniques detected acid anions, so were consistent with the chemisorption of the acid molecules on the surface. In addition, high mass fragments were detected in the FABSIMS spectra that are associated with oxide clusters and appear to be characteristic of the adsorbed state of the organic acid on the surface. Results from FABSIMS analysis of a sample from a hot rolling mill indicate that similar types of reaction occur in the rolling process.

The application of static secondary ion mass spectrometry to the study of epoxy adhesive constituents

The application of fast atom bombardment secondary ion mass spectrometry (FAB-SIMS) with quadrupole mass analysis to the study of some of the common constituents present in epoxy adhesive formulations is described and the potential of the technique evaluated. The compounds investigated were Epikote 828 (mainly diglycidyl ether of bisphenol-A) and the cross-linking agent dicyandiamide. The characteristic secondary ion spectra recorded for both materials exhibited a number of identifiable and uniquely diagnostic signals, which should be of use in the study of surface and interface adhesive chemistry.

A FAB-SIMS/SNMS apparatus

A FAB-SIMS/SNMS (fast atom bombardment secondary ion mass spectrometry and sputtered neutral mass spectrometry) apparatus has been studied. In the apparatus, an electron bombardment ionizer for ionization of sputtered neutrals and a quadrupole mass spectrometer for mass analysis are used. The primary beam is the fast oxygen atom beam with about 2.5 keV of the kinetic energy and 10 14 atoms/s of the intensity. Secondary ion spectra and sputtered neutral spectra are obtained in similar intensity for samples of a Cu-Be alloy and a polyethylene film. As the primary beam has no electric charge, even insulator samples are easily analyzed without any trouble caused by electrical charging on the sample surface.

FAB-SIMS and LIMS.

FAB-SIMS (Fast Atom Bombardment Secondary Ion Mass Spectrometry) and LIMS (Laser Ionization Mass Spectrometry) have been explained.FAB-SIMS is a kind of SIMS in which a fast atom beam is used for the primary beam for sample bombardment. It is useful for insulator samples as sample surface charging caused by charge of the primary beam does not occur. The relative intensity for various elements by FAB-SIMS is similar to that of normal SIMS.LIMS is an analytical device in which pulsively generated ions by pulsed laser radiation on solid state samples are generated from samples through thermal ionization or through LTE process of microplasma produced on laser-heated sample sufaces. LIMS has extremely high sensitivity of 10-1810-20gr.