Nanometer pattern-mask fabricated by conventional photolithography

A novel method to fabricate a nanometer-size pattern-mask by conventional photolithography is proposed. In the method, titanium oxide (TiO2) grown laterally by anodic oxidation at the side-edge of a thin titanium (Ti) layer is utilized to fabricate nanometer-size patterns. The detailed processes and conditions for each process such as anodic oxidation are studied. It is found by scanning electron microscopy (SEM) that the nanometer-size patterns can be fabricated and the size is precisely controlled by the anodic voltage. It is also confirmed by atomic force microscopy (AFM) that a Ti pattern-mask with a slit of a few tens of nanometer width can be fabricated by the present method.