A progress review of proton beam writing applications in microphotonics

The proton beam writing technique is a direct write lithographic technique that is being actively developed at the Centre for Ion Beam Applications, National University of Singapore for microphotonic applications. The technique utilizes a highly focused beam of MeV protons to pattern or modify the refractive index of various materials including polymers, glasses and other inorganic crystals. The technique has been applied to the fabrication of several different types of microoptical components including waveguides, gratings, microlens arrays and colloidal crystal templates. In this paper we give a review of the progress made thus far by our group and other workers in the field of microphotonics using proton beam writing.