Applications of polymer post processing of silicon on insulator (SoI) devices are demonstrated. Polymer overlays on SoI nanophotonic circuits are used, on the one hand, to improve optical antenna transception for an any-one-to-all array and, on the other hand, a similar photodefinable coating is used to passively tune the dispersive characteristics of waveguides embedded in photonic crystals. Discussion is given to the polymer formulation. Coating that requires infiltration into voids with dimension 100 nm and less demands optimized wetting properties from the pre-cured polymer-in-solution. Atomic Force and Scanning Electron micrographs and Zygo interferometer image illustrate the quality of the post-photo-definition, cured coatings. Transmission measurements show a 10 dB improvement in the received signal level for a coated versus uncoated antenna pair radiating and receiving at 1550 nm. Wavelength dependent transmission measurements on waveguides in photonic crystals demonstrate that tuning can be affected in post processing performed after foundry fabrication. Careful formulation of the polymer for nano infiltration allows for tuning without increased attenuation.

Date Published: 23 August 2011
PDF: 10 pages
Proc. SPIE 8173, Photonics 2010: Tenth International Conference on Fiber Optics and Photonics, 81730H (23 August 2011); doi: 10.1117/12.898181

Published in SPIE Proceedings Vol. 8173:
Photonics 2010: Tenth International Conference on Fiber Optics and Photonics
Sunil K. Khijwania; Banshi D. Gupta; Bishnu P. Pal; Anurag Sharma, Editor(s)