Production of C microbeams by single-microcapillary methods

Tsuchida, Hidetsugu*; Majima, Takuya*; Tomita, Shigeo*; Sasa, Kimikazu*; Narumi, Kazumasa; Saito, Yuichi; Chiba, Atsuya; Yamada, Keisuke; Hirata, Koichi*; Shibata, Hiromi*; Ito, Akio*

Transmission properties of sub-MeV C ions through a capillary were investigated. A 360-keV C or 720-keV C primary ion beam obtained from a 400-kV ion implanter was introduced into a single capillary, whose outlet diameter was 5.5 or 14 m, mounted on a goniometer. Particles emerging from the outlet of the capillary were deflected with electrostatic parallel plates and detected by a microchannel plate with a phosphor screen to obtain information about their composition. Some interesting results have been obtained from this measurement: (1) a main component of transmitted particles is C beams, due to direct transmission, (2) the other components are unknown-size neutral particles, and large-size fragments of C or C ions produced via C-emission from C, and (3) small-sized carbon fragments of C or C ions resulting from C-multifragmentation are not detected, which suggests that most of them are detected as neutral particles.