Depth-modulated buried channel waveguides by direct-write focussed ion beam irradiation

Abstract

The fabrication of buried waveguides with modulated depths through MEV ion irradiation is reported. Irradiation of the substrate through a tapered film attenuated the ion energy and varied the depth at which a single waveguide is formed. The resulting waveguides change in depth over a 40 micron range, but have uniform cross sections along their length. A three-dimensional direct-write technique can be achieved by moving the tapered film while scanning the sample in two dimensions with respect to the beam.