Development of the Jyväskylä microbeam facility

A new microbeam facility is being constructed at the 1.7 MV Pelletron Accelerator in Jyväskylä. The facility is designed for easy upgrading and incorporates a number of innovative features. Initially, it is based on a Heidelberg doublet with a design capability of a 3 × 5 μm beamspot at PIXE intensities and later upgraded to nanobeam performance. A thermal-expansion compensated rigid frame mounted on a mechanically isolated floor section is used to support the ion optical components. A compact-post focusing electrostatic deflector is used for high linearity beam scanning. This together with a novel time-stamped data collection (TDC) allows dynamic effects in IBIC, fluorescence bleaching to be studied as well as facilitating multi-resolution image support for low-fluence imaging of cells. The target chamber is fitted with a novel low-cost large working distance optical microscope, extremely compact large solid angle photon detectors as well as conventional secondary electron, PIXE and Scanning Transmission Ion Microscopy (STIM) detectors.

Research highlights
► A MeV ion microbeam for biomedical materials research is being developed.
► High accuracy scanning using electrostatic post-focus deflection.
► Imaging and direct lithographic image writing using time-stamping methods.
► New scanning modes and fluorescence detectors permit low ion-fluence cell imaging.
► Thermal compensated beam-line support design for high positional accuracy.