Conductive Distributed Bragg Reflector Fabricated at Low Temperature

A conductive DBR electrode fabricated using the single Indium tin oxide (ITO) conductive material is proposed. The high refractive index of the dense ITO film was achieved by RF sputtering at room temperature and the porous ITO film with low refractive index was prepared by applying supercritical CO2 (SCCO2) treatment at 60 °C on gel-coated ITO thin films. The index contrast of the ITO bilayers was higher than 0.5 at a wavelength of 550 nm. In addition, small deviations on the optical thickness of the ITO bilayers were observed during the DBR stacking processes. For the DBR comprising 4 periods ITO bilayers, the reflectance and sheet resistance of 72.8% and 35 Ω/ were achieved.