Pulsed ion beams of short duration are used in Time of Flight ion scattering measurements for surface analysis. Shorter pulse widths result in high timing resolution which manifests itself in more accurate mass and depth resolutions. Limits to minimum pulse widths are associated with ion velocities, energy spreads, beam spot size, pulsing technique, system stability, etc.
The Peabody Scientific PIBS system employs techniques and standard beam line components that are mutually compatible for achieving proper ion beam pulsing.
A drawing of the PIBS system is shown in Figure 1. A Duoplasmatron Ion Source produces an intense beam of gaseous ions (H, He,) which are then extracted by an Extraction Gap. A divergent beam of ions is produced with energies variable from 3 to 25 keV. The inherent energy spread of the Duoplasmatron is very low (<20 eV) so that a beam with a final energy spread of less than 50 eV can be produced. The beam is
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