Focusing of MeV ion beams by means of tapered glass capillary optics

Abstract

We present evidence of the focusing effects of fine glass capillary optics for MeV He ion beams. The glass capillary optics are formed by a puller as to have inlet diameters of about 1 mm and outlet diameters of submicrons. The total length of the optics is about 50 mm. Impingent MeV ions to such optics are reflected by the inner wall several times, in a very similar process to the so-called surface channeling. The majority of incident ions are lost by the dechanneling, or large-angle scattering process, however, a part of them, actually about 1% more or less, is emitted through the outlet without significant energy loss. Compared with the conventional micro-ion beam facilities, the present method is certainly simple and lowcost, thus providing an easy method of submicron Rutherford backscattering spectrometry or particle induced x-ray emission analyses. In addition, if the ion species are extended to heavier elements, the present method provides versatile maskless ion implantation techniques.

Production of a microbeam of slow highly charged ions with a tapered glass capillary

“…A similar glass capillary was used to transport proton or He ion beam in a MeV region. 9 In this case, however, the beam touches the inner wall and suffers small angle scattering with the wall surface during the transport.…”

Ion irradiation in liquid of μm3 region for cell surgery

“…To overcome such technical but serious problems, we have developed a scheme using a tapered glass capillary with a thin window at its outlet. 12,13 This scheme can realize pinpoint energy deposition and three-dimensional selection of the bombarding point by observing the outlet through a microscope with a precision of a micron or better in an arbitrary position of a living cell or in any liquid object. Figure 1͑a͒ shows a drawing of the microbeam preparation setup installed on an X-Y stage, which is aligned by the upstream micrometers with respect to the beam line.…”

“…1͑b͔͒ with inlet and outlet diameters of 0.8 mm and several micrometers, respectively. 12,13 The downstream micrometers are used to align the capillary to the beam axis with a step of 0.5 mrad. The capillary outlet is placed in the focus of an optical microscope, which is installed on a three-dimensional stage.…”

Microbeams of Visible Light by Tapered Glass Capillaries

“…Recently, many studies have been reported on microbeam production of keV-MeV accelerated ions using tapered glass capillaries [1][2][3]. Microbeams by the capillaries have advantages of low cost, easily positioning on the target and preferable sizes of beams.…”