title: Tomographic Spectral Imaging with Multivariate Statistical Analysis: Comprehensive 3D Microanalysis.
abstract: A comprehensive three-dimensional (3D) microanalysis procedure using a combined scanning electron microscope (SEM)/focused ion beam (FIB) system equipped with an energy-dispersive X-ray spectrometer (EDS) has been developed. The FIB system was used first to prepare a site-specific region for X-ray microanalysis followed by the acquisition of an electron-beam generated X-ray spectral image. A small section of material was then removed by the FIB, followed by the acquisition of another X-ray spectral image. This serial sectioning procedure was repeated 10-12 times to sample a volume of material. The series of two-spatial-dimension spectral images were then concatenated into a single data set consisting of a series of volume elements or voxels each with an entire X-ray spectrum. This four-dimensional (three real space and one spectral dimension) spectral image was then comprehensively analyzed with Sandia's automated X-ray spectral image analysis software. This technique was applied to a simple Cu-Ag eutectic and a more complicated localized corrosion study where the powerful site-specific comprehensive analysis capability of tomographic spectral imaging (TSI) combined with multivariate statistical analysis is demonstrated.
authors.affiliation: Sandia National Laboratories, Materials Characterization Department, P.O. Box 5800, MS0886, Albuquerque, NM 87185-0886, USA. pgkotul@sandia.gov
authors.forename: Paul G
authors.initials: PG
authors.lastname: Kotula
authors.forename: Michael R
authors.initials: MR
authors.lastname: Keenan
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Michael
mesh_terms: D004577:Electron Probe Microanalysis; D008670:Metals; D008958:Models, Molecular; D015999:Multivariate Analysis; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
chemical_list: D008670:Metals