BNCT医療用中性子源用Liターゲットのin-situリチウム蒸着とイオン注入合成法と熱的化学的安定性

Synthesis and thermo-chemial stability of Li target for nuetron production target of BNCT by in-situ lithium deposition and ion implantation

石山 新太郎; 馬場 祐治  ; 藤井 亮*; 中村 勝*; 今堀 良夫*

Ishiyama, Shintaro; Baba, Yuji; Fujii, Ryo*; Nakamura, Masaru*; Imahori, Yoshio*

実装配備が予定されているBNCT治療装置のLiターゲット部のin-situ蒸着とイオン注入とを融合化させた量子ビーム融合化技術によるLiN/Li/Pd/Cu積層ターゲットモデルの合成に成功した。本モデルは長時間大気暴露後も安定した特性を有することが明らかとなった。

To achieve high performance of BNCT (Boron Neutron Capture Therapy) device, LiN/Li/Pd/Cu four layered Li target was designed and the structures of the synthesized four layered target were characterized by X-ray photoelectron spectroscopy. For the purpose of avoiding the radiation blistering and lithium evaporation, vacuum deposition and nitridation techniques were established for production and repairing maintenance of the lithium target. Following conclusions were derived;(1) Uniform lithium layer of a few hundreds nanometer was formed on Pd/Cu multilayer surface by vacuum deposition technique using metallic lithium as a source materialand lithium nitrides were formed by nitridation reaction by the implantation of low-energy nitrogen ions on the deposited lithium layer surface. (2) This nitridated zone formed on surface of four layered lithium target is stable for a long time in air condition.