A compact micro-beam system using a tapered glass capillary for proton-induced X-ray radiography

New type of capillary for use as ion beam collimator and air-vacuum interface

“…to deposit small amounts of liquids [1], for chemical analysis using capillary electrophoresis (CE) [2] and for focussing of X-ray beams [3,4]. Recently a new application, ion beam collimation with glass capillaries, has been implemented at various ion beam analysis (IBA) laboratories [5][6][7][8][9][10][11] and some publications even reported a gain in fluence after the capillary exit [12,13]. Compared to the usually used electromagnetic lenses a capillary offers a cost effective alternative for micrometre diameter ion beam generation.…”

Peculiarities of Swift Proton Transmission through Tapered Glass Capillaries

“…Slightly tapered glass capillaries with micro or submicro outlet diameters attract much attention as ion beam focusing lens [1][2][3][4]. The smallest beam spot size obtained so far was 0.3 µm [1].…”

“…The smallest beam spot size obtained so far was 0.3 µm [1]. Previous studies have demonstrated the focusing effect with respect to many kinds of ions and energies [1][2][3][4]. The focusing factor of a glass capillary, defined as the ratio of areal current density at the inlet and outlet, depends on the ion species, the incident energies and the shape of glass capillary.…”

“…The focusing factor of a glass capillary, defined as the ratio of areal current density at the inlet and outlet, depends on the ion species, the incident energies and the shape of glass capillary. This factor of 8 keV Ar 8+ is about 10 and for 2 MeV He + beam amounts to about 1000 [1][2][3][4]. The purpose of the present report is to study the dependence of proton transmission through capillaries on capillary taper angles.…”

“…The purpose of the present report is to study the dependence of proton transmission through capillaries on capillary taper angles. An ion energy region was chosen to satisfy the experimental conditions of local implantation, local elemental and structure analysis, micro-and nanolithography, X-ray radiography, and applications in biology and medicine [3,5]. For example, this technique enables in-air particle-induced X-ray emission (PIXE) measurements of various samples that are not compatible with the vacuum environment [2] (wet solids, liquids and gases).…”