Fabrication of three-dimensional pillar arrays by PBW for improved trapping performance of dielectrophoretic devices

誘電泳動における捕獲性能の改良のためのPBWによる三次元ピラー配列の製作

椎根 康晴*; 坂下 裕介*; 西川 宏之*; 佐藤 隆博; 石井 保行; 神谷 富裕; 中尾 亮太*; 内田 諭*

Shiine, Yasuharu*; Sakashita, Yusuke*; Nishikawa, Hiroyuki*; Sato, Takahiro; Ishii, Yasuyuki; Kamiya, Tomihiro; Nakao, Ryota*; Uchida, Satoshi*

Proton beam writing (PBW) is a direct writing technique using MeV focused proton beams. A dielectric pillar array for a dielectrophoresis (DEP) trapping site of food poisoning microbes is fabricated as an application of PBW. The high-aspect-ratio pillar arrays with the height of several tens of micrometers have, so far, been fabricated by PBW to increase the effective density and volume of the DEP trapping sites, whose effectiveness was demonstrated by the trapping experiments of Escherichia coli (E. coli) of the microbes. In this study, dielectric pillar arrays with the multi-level 3D structures of SU-8 were fabricated to further improve their trapping efficiency. In this fabrication, the combination technique of PBW and the hydrogen ion beam writing (HBW) which was a PBW technique using 1.0 MeV H beam was used to irradiate SU-8 in a short time by switching from the proton beam to hydrogen ion beams with the same energies but different penetration depths. The irradiation of PBW and HBW was preformed by the dedicated PB writer at Shibaura Institute of Technology. The fabrication of the dielectric pillar arrays with the multi-level 3D structures was successfully done using the combination technique. The results of the fabrication and their performance tests will be shown in the presentation in detail.