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Accelerator-based analytical facility (AAF) of the Institute of Applied Physics of the National Academy of Sciences of Ukraine is described. The research facility is based on a compact single ended machine with the maximum accelerating potential of 2 MV. The facility has five analytical end-stations: an scanning ion microprobe end-station with spatial resolution of less than 2 μm, a high-resolution Rutherford backscattering spectrometry end-station with a magnetic spectrometer (ΔE/E

The paper discusses the feasibility of constructing a compact nuclear microprobe combining ion acceleration and ion probe formation. In the design proposed a mass-separator, object-and angular collimators are placed at the accelerating tube entrance. Immediately behind the accelerating tube a quadruplet of magnetic quadrupole lenses is positioned to provide final ion probe formation at the target. Using the accelerating tube, which is an extended electrostatic immersion lens with axial symmetry together with magnetic quadrupole lenses to form an ion microprobe, it is possible to find conditions permitting the total aberration level to be reduced. Numerical optimization of the probe-forming system was performed involving the maximum emittance method developed by the authors in earlier papers. The calculations show that with a 3 MeV accelerator, the design proposed would allow generation of a H+ ion beam with a 0.4 μm spot size and 3.15 μm2 mrad2 MeV normalized emittance. The total length of the facility is about 4 m.

The probe-forming system of a nuclear scanning microprobe based on the parametric multiplets of quadrupole lenses is optimized. The optimization is aimed at creating an ion probe with energy of several MeV that produces a micrometer spot on the target at a current of ∼100 pA. The influence of different geometric and physical parameters on the ion-optical properties of the probe-forming systems considered is determined. The optimization is carried out by varying the parameters specifying a given parametric multiplet, and its efficiency is found from a quality criterion that takes into account the beam current for given sizes of the spot and target. The beam parameters at the entrance to and at the exit from the EGP-10 electrostatic tandem accelerator (produced by the VNIIEF) are involved in the optimizing calculations. These are the maximal energy, normalized brightness, transport conditions, and chromatic inhomogeneity of the beam (i.e., the energy straggling of beam particles). Allowance is also made for the parasitic components of the magnetic quadrupole lens field, which arise because of quadrupole symmetry breaking by technological and physical reasons.