Applications of scanning transmission ion microscopy

Abstract

Abstract The use of scanning transmission ion microscopy (STIM) in conjunction with scanning PIXE (proton induced X-ray emission) and RBS (Rutherford backscattering spectrometry) represents a powerful combination of imaging and analytical techniques across a wide range of scientific disciplines. In the microelectronics field STIM is a valuable complement to PIXE and RBS for the characterisation of the layer distribution, composition and uniformity in complex microcircuits. A microcircuit with several metallisation layers has been studied using these three techniques. A defect in the metallisation structure has been imaged with STIM, and PIXE has been used to determine the nature of the defect. In the field of biological microanalysis, tissue is usually stained or otherwise chemically treated in order to identify pathological features prior to analysis. This inevitably leads to a reduction in the integrity of the sample, introducing problems both of contamination and the possible loss of elements of interest from the tissue. Results showing how STIM and PIXE can be used to analyse pathological features in unstained tissue from the brains of Alzheimer's disease patients are given.