Low temperature Electron Cyclotron Resonance plasma technique for low loss integrated optics

Abstract

Electron Cyclotron Resonance (ECR) plasma deposition process implies low temperatures at high deposition rates producing uniform and mechanically stable thin films. For these reasons ECR became an attractive tool for integrated optics technology. In this work we have combined ECR with other techniques as Reactive lon Etching (RIE) and Pulsed Laser Deposition (PLD), in order to develop a new fabrication method of channel waveguides. We report here results on alumina-based strip-loaded waveguides. Amorphous Al 2O 3 core of 0.7 μm were deposited over Si/SiO 2 substrate by PLD technique and overcladded with a 0.5 μm SiO 2-ECR film. Standard UV-photolitographic techniques and RIE were used to define a set of strips on the SiO 2. These strips give the additional confinement of the light in the Al 2O 3 core. The optical losses at 633 nm were measured using an imaging technique. The relative scattered light power as function of the propagation along the channels shows a maximum optical loss of 4.5 dB/cm.