Silicon-on-Insulator Optical Rib Waveguide Loss and Mode Characteristics

Abstract

Optical rib waveguides with rib heights of 3.17 and 7.67 microns with various widths have been formed in separation by implantation of oxygen (SIMOX) based silicon-on-insulator (SOI) structures. The effect of waveguide rib etch depth, width, and interface roughness on loss and mode characteristics have been studied at wavelengths of 1.15 and 1.523 microns. The experimental results support the hypothesis that certain rib dimensions can lead to single mode SOI waveguides even though planar SOI waveguides of similar multimicron dimension are not single mode. Mode loss was found to be strongly dependent on interface roughness and mode confinement. 0733-8724/94#04.00 © 1994 IEEE