Ion microprobe mass analyzer

Fig. I, Schematic representation of the ion microprobe mass analyzer. (Bausch Lomh/ARL)...

The ion microprobe mass analyzer s unique features permit three dimensional microanalysis of all elements in the periodic table and in... 

Recent studies on iron sulfide minerals in coals, minerals in coals, and in situ investigation of minerals in coal all used the scanning electron microscope (SEM) as the primary analytical tool. The ion microprobe mass analyzer (IMMA) is more sensitive than either the energy-dispersive x-ray spectrometer or the wavelength-dispersive x-ray spectrometer, both of which are used as accessories to an electron microscope. 

In 1967 Liebl reported the development of the first imaging SIMS instrument based on the principle of focused ion beam scanning [24]. This instrument, the ion microprobe mass analyzer, was produced by Applied Research Laboratories (Fig. 4.5). It used an improved hollow cathode duoplasmatron [25] ion source that eliminated filaments used in earlier sources and allowed stable operation with reactive gases. The primary ion beam was mass analyzed for beam purity and focused in a two-lens column to a spot as small as 2 pm. The secondary ions were accelerated from the sample surface into a double focusing mass spectrometer of Mattauch-Herzog geometry. Both positive and negative secondary ions were de-... 

Figure 5 Ion microprobe mass analyzer, first scanning-probe imaging secondary ion mass spectrometer (SIMS). (From Ref. 24.)...

Figure 6 Isotope deflector plates in ion microprobe mass analyzer.

Cristy, S. S., Ferree, D. V., Nolan, T. A., and McCulla, W. H., Studies of Oxide and Fluoride Films on Metals Using an Ion Microprobe Mass Analyzer, Y-DA 4815, Union Carbide Corporation—Nuclear Division, Oak Ridge Y-12 Plant, Oak Ridge, TN (1972). 

Hinthorne,J.R., Andersen, C.A. (1975) Microanalysis for fluorine and hydrogen in silicates with the ion microprobe mass analyzer. Am. Mineral, 60,143-147. 

DIMA Direct imaging mass analyzer IMMA Ion microprobe mass analyzer... 

C. A. Anderson, Progress in analytical methods for the ion microprobe mass analyzer, Int. J. Mass Spectry. Ion Phys. 2, 61-74 (1969). 

There are now several different types of machines that are all capable of microanalysis. All have advantages and disadvantages, but the choice of which to use is often governed by expense and availability to a particular institution. Electron probe microanalysis is by far the most popular, but here particle-induced X-ray emission (PIXE), the laser microprobe mass analyzer (LAMMA), electron energy loss spectroscopy (EELS), and secondary ion mass spectrometry (SIMS) are also considered. 

Optical examination of etched polished surfaces or small particles can often identify compounds or different minerals hy shape, color, optical properties, and the response to various etching attempts. A semi-quantitative elemental analysis can he used for elements with atomic number greater than four by SEM equipped with X-ray fluorescence and various electron detectors. The electron probe microanalyzer and Auer microprobe also provide elemental analysis of small areas. The secondary ion mass spectroscope, laser microprobe mass analyzer, and Raman microprobe analyzer can identify elements, compounds, and molecules. Electron diffraction patterns can be obtained with the TEM to determine which crystalline compounds are present. Ferrography is used for the identification of wear particles in lubricating oils. 

In general, in ICP-MS, metal argide ions (MAr+) are observed at lower intensities compared to the dimeric metal oxide ions (MO+). Both ionic species correlate with the bond dissociation energies in the ICP or by the expansion of plasma in the vacuum. A correlation of measured oxide ion intensities (MO+) and experimentally determined or theoretically calculated bond dissociation energies of oxides has been found in laser mass spectra using a LAMMA 500 (laser microprobe mass analyzer, Leybold Hereaus AG, Cologne) by Michiels and Gijbels.52... 

Laser microprobe mass analyzers permit mass spectrometric analysis of very small volumes (0.01-1 pm3) of thin Sections. The method is based on laser induced ion production from a microvolume and analysis of the evaporated ions in a time-of-flight mass-spectrometer. The technique allows detection of all elements and isotopes with a sensitivity approaching the ppm range and an extremely low limit of detection 10 15 to 10-20 g. Transmission type instruments such as the LAMMA 500 are designed for the analysis of particles of 3 pm in diam. The lateral resolution is about 0.5-1 pm. Because the area to be analyzed is selected by an optical microscope, distribution of chemical constituents can be precisely correlated with morphologic structures (Hillenkamp et al., 1982 39), Simons, 198440), Kaufmann, 1984)41 >. 

Ions Ion Scattering Mass Spectroscopy, Laser Microprobe Mass Analyzer, Rutherford Backscattering Spectroscopy, Secondary Ion Mass Spectroscopy. 

Guest, W. H. Recent developments of laser microprobe mass analyzers, lamma-500 and lamma-1000. Int. J. Mass Spectrom. Ion Processes 1984, 60, 189-199. 

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