We report on the progress that has been made on the realisation of narrow spectrum photonic crystal filters operating in the communications band. The development of a process for the deposition of silicon-silicon dioxide super-lattices using RF reactive sputtering is described. The use of reactive sputtering of silicon dioxide from a silicon target enables a much higher deposition rate than could be achieved using a SiO2 target. The characteristics of these films are shown to closely match the widely accepted values for silicon dioxide over a wide range of wavelengths. The cross-sectional SEM micrograph of a super-lattice deposited in this manner is presented which shows clearly the alternating layers with well-defined interfaces. (c) 2005 Elsevier B.V. All rights reserved.