High Refractive Index Dielectric Prepared by Electron Beam Evaporation for Photonic Crystal Optical Biosensor Application

Abstract

The fabricated photonic crystal biosensor device consists of SOG material and titanium dioxide (TiO2) thin films as low and high refractive indexes dielectric layers, respectively. Nano-Imprinting Lithography (NIL) process was used to duplicate periodic line as grating structure from Ni-master mold onto SOG/glass. High refractive index dielectric thin film layer was deposited by using electron beam evaporation system. The surface morphology and thickness of thin film are characterized by atomic force microscope (AFM) and field emission scanning electron microscope (FE-SEM), respectively. The optical measurement system is set up to observed the sensitivity of fabricated device. A shift of reflected peak wavelength observed from DI-water and IPA was tested. The morphology and the thickness of the prepared dielectric thin films are affected to the efficiency of fabricated device.