Gesellschaft Fur Strahlen- Und Umweltforschung Mbh, Munchen

Gesellschaft Fur Strahlen- Und Umweltforschung Mbh (gsf)

Klaus Wittmaack

A method and an apparatus for the quantitative depth analysis of a solid sample by backscatter analyzing the sample with the light ions, removing a thin layer of the sample by sputter etching, using a beam of medium-mass or high-mass ions to bombard the sample, backscatter analyzing the sputter etched sample, and repeatedly performing the steps of removing a thin layer of the sample and backscatter analyzing the sputter etched sample. An apparatus for performing the method includes an analysis chamber for retaining the sample to be analyzed, and first and second accelerators. The first accelerator generates fast, light ions with an energy from about 0.1 MeV to about 5.0 MeV to be directed into the chamber onto a predetermined region of the sample at a first desired predetermined bombardment angle so that the fast ions are scattered by the ions of the sample. The second accelerator accelerates a beam of slow medium-mass or high-mass ions with an energy from about 0.5 to about 10.0 keV to be directed onto the predetermined region of the sample at a second desired predetermined bombardment angle. The analysis chamber has a sample manipulator for manipulating the sample and an analyzer for determining the energy of the fast ion scattered by the atoms of the sample.

Method and apparatus for the quantitative, depth differential analysis

A raster scanning ion microscope for determining, with a large field of view, the lateral distribution of elements, isotopes and compounds at the surface and in the bulk of solid specimens and for displaying the surface topography of the sample. The scanning ion microscope consists of an ion gun to produce a primary ion beam, a means to focus and raster scan the primary ion beam over the surface of the specimen, a means to form a beam of secondary ions out of all particles sputtered from the specimen, an energy analyzer and a mass spectrometer for secondary ion analysis and a means for optimum transport of the secondary ions from the specimen to the mass spectrometer. Use of a quadrupole mass filter as a mass analyzer reduces restrictions usually faced with magnetic type mass analyzer and allows imaging of the specimen with a large field of view. Moreover non-normal secondary ion extraction and/or non-normal primary ion incidence in combination with low secondary ion extraction voltages result in the capability of the instrument of displaying the surface topography of the specimen.

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Munich, Germany

Klaus Wittmaack