Fabrication of Complex integrated Waveguide filters using Electron Beam Lithography

Abstract

Integrated waveguide filters have recently been used in many optical processing applications including the filtering[1] multiplexing[2] and switching[3] of optical signals. In particular chirped grating have been for dispersion compensation in optical fiber systems[4] and apodization is commonly used to suppress the production of sidelobes in the transmission characteristics of grating filters. It is envisaged that in the future telecommunications and optical computing networks will require novel and complex grating structures for the processing and selective switching applications in multi-channel systems. Therefore, a simple and reliable method for the production of grating filters, where the filter charcteristics can be easily tailored is desired. In this letter we describe a single step, electron beam based approach, where the grating and waveguide are defined simultaneously and the grating characteristics arc well controlled.