Fabrication of 80 nm-Wide Lines in FPM Resist by H⁺ Beam Exposure

80 nm-wide lines in FPM resist have been fabricated by ion beam exposure through a Au mask with a very low dose of 3×10 -7 C/cm 2 . The Au mask-pattern was fabricated by means of an oblique evaporation technique on FPM resist for irradiation by a 50 keV H + beam. It was confirmed that the substrate did not affect the dissolution characteristics of the FPM after the ion beam exposure. These features lead to the possibility of applying various resists other than PMMA to nanometer-lithography, making good use of their high sensitivity and/or high resistance to dry etching.