Three dimensional nano-micro processing for polymer films by MeV ion beam lithography

Takano, Katsuyoshi*; Asano, Atsushi*; Maeyoshi, Yuta*; Marui, Hiromi*; Omichi, Masaaki*; Saeki, Akinori*; Seki, Shu*; Sato, Takahiro; Kamiya, Tomihiro; Ishii, Yasuyuki; Okubo, Takeru; Koka, Masashi; Kada, Wataru; Sugimoto, Masaki; Nishikawa, Hiroyuki*

The fine strings of epoxy-resin were fabricated using a focused MeV ion beam in this paper. This fabrication was carried out by the following four steps. Firstly, an epoxy-resin layer was spin-coated on a epoxy-resin film cured by electron beam irradiation as a substrate. Secondly, bridge patterns were irradiated on the epoxy-resin layer by Proton Beam Writing two times with the two different energies which led its proton beam to the two different penetration depths. Thirdly, focused 520 MeV Ar particles were irradiated at aiming the bridge patterns, controlling a spot pattern. Finally, the development of the irradiated epoxy-resin files was carried out using the supercritical carbon dioxide fluid, CO to etch the non-irradiated area under reducing the surface tension among areas of sub-micrometer size. The epoxy-resin fine strings with the diameter of 0.8 m was observed between the bridge structure with the height of 20 m and the substrate using a scanning electron microscope. A microprocessing for fine strings of a epoxy-resin was demonstrated using a focused several hundred MeV ion beam.