SCANNING TUNNELING MICROSCOPE TIP-INDUCED ANODIZATION OF TITANIUM - CHARACTERIZATION OF THE MODIFIED SURFACE AND APPLICATION TO THE METAL RESIST PROCESS FOR NANOLITHOGRAPHY

Nanometer scale oxide patterns were fabricated on titanium (Ti) surfac es on the basis of scanning tunneling microscope (STM) tip-induced ano dization. The spatial resolution of the method was limited to approxim ately 20 nm, owing to the surface roughness of the Ti film used. Chemi cal analyses of fabricated patterns by Auger electron spectroscopy pro ved that the surface chemical composition of the pattern was titanium dioxide (TiO2), and the oxide thickness on the pattern was certainly t hicker than that of the native oxide on the unmodified area. A novel T i-metal resist process for nanolithography based on STM tip-induced an odization was proposed. The Ti film on which anodized patterns were fo rmed could be etched by hydrofluoric acid using the anodic oxide patte rns as an etching mask. Ti lines of similar to 60 nm in width were suc cessfully fabricated by the present method.