Share Email Print

Proceedings Paper

Mode-converting coupler for silicon-on-sapphire devices
Author(s): S. Zlatanovic; Bruce W. Offord; Michael W. Owen; R. Shimabukuro; E. W. Jacobs
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Silicon-on-sapphire devices are attractive for the mid-infrared optical applications up to 5 microns due to the low loss of both silicon and sapphire in this wavelength band. Designing efficient couplers for silicon-on-sapphire devices presents a challenge due to a highly confined mode in silicon and large values of refractive index of both silicon and sapphire. Here, we present design, fabrication, and measurements of a mode-converting coupler for silicon-on-sapphire waveguides. We utilize a mode converter layout that consists of a large waveguide that is overlays a silicon inverse tapered waveguide. While this geometry was previously utilized for silicon-on-oxide devices, the novelty is in using materials that are compatible with the silicon-on-sapphire platform. In the current coupler the overlaying waveguide is made of silicon nitride. Silicon nitride is the material of choice because of the large index of refraction and low absorption from near-infrared to mid-infrared. The couplers were fabricated using a 0.25 micron silicon-on-sapphire process. The measured coupling loss from tapered lensed silica fibers to the silicon was 4.8dB/coupler. We will describe some challenges in fabrication process and discuss ways to overcome them.

Paper Details

Date Published: 27 February 2015
PDF: 6 pages
Proc. SPIE 9367, Silicon Photonics X, 93670W (27 February 2015); doi: 10.1117/12.2079671
Show Author Affiliations
S. Zlatanovic, Space and Naval Warfare Systems Ctr. Pacific (United States)
Bruce W. Offord, Space and Naval Warfare Systems Ctr Pacific (United States)
Michael W. Owen, Defense Microelectronics Activity (United States)
R. Shimabukuro, Space and Naval Warfare Systems Ctr. Pacific (United States)
E. W. Jacobs, Space and Naval Warfare Systems Ctr. Pacific (United States)

Published in SPIE Proceedings Vol. 9367:
Silicon Photonics X
Graham T. Reed; Michael R. Watts, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?