Photocatalytic Lithography Based on Photocatalytic Remote Oxidation

Abstract

Photocatalytic lithography is a method for surface patterning based on photocatalytic remote oxidation. A TiO₂-coated photomask is faced with a surface to be patterned, and irradiated with UV light. If a glass plate modified with alkyl chains is used, hydrophilic/hydrophobic patterns can be obtained. The alkyl chains in the irradiated regions are removed by oxidative decomposition, and those in the non-irradiated regions are left. Irradiation time is 30-60 s, and resolution is about 5 μm. This technique is potentially applicable to fabrication of biochips, lab-on-a-chip devices and simple electronic circuits.