Title :
Fabrication and characterisation of a CdS-doped silica-on-silicon planar waveguide
Author :
Fardad, M.A. ; Yeatman, E.M. ; Dawnay, E.J.C. ; Green, M. ; Fick, J. ; Guntau, M. ; Vitrant, G.
Author_Institution :
Dept. of Electr. & Electron. Eng., Imperial Coll. of Sci., Technol. & Med., London, UK
fDate :
10/1/1996 12:00:00 AM
Abstract :
A planar silica-titania waveguide doped with CdS nanocrystallites has been fabricated on a silicon substrate. A passive nanoporous host layer and a pure silica buffer layer, of thickness 2.2 and 7.5 μm, respectively, were deposited by the sol-gel technique. Crystallites were then precipitated in the porous matrix by soaking in a CdF2 solution followed by reaction in H2S gas, and a sputtered layer of silica was used to seal the structure. The absorption spectrum of an equivalent film indicates crystallites with radii up to ~26 Å, while energy dispersion spectroscopy indicates a dopant concentration of ~0.5 volume%. The third order optical nonlinearity (Kerr effect) was measured using an m-line technique, yielding a value of ~5×10-9 cm2/kW
Keywords :
II-VI semiconductors; cadmium compounds; nanostructured materials; optical Kerr effect; optical fabrication; optical planar waveguides; silicon; silicon compounds; silicon-on-insulator; sol-gel processing; substrates; ultraviolet spectra; visible spectra; 2.2 mum; 7.5 mum; CdF2; CdF2 solution; CdS nanocrystallites; CdS-doped silica-on-silicon planar waveguide fabrication; H2S; H2S gas; Kerr effect; SiO2:CdS-Si; absorption spectrum; crystallites; dopant concentration; energy dispersion spectroscopy; equivalent film; m-line technique; passive nanoporous host layer; planar silica-titania waveguide; porous matrix; pure silica buffer layer; silicon substrate; sol-gel technique; sputtered layer; third order optical nonlinearity;
Journal_Title :
Optoelectronics, IEE Proceedings -
DOI :
10.1049/ip-opt:19960836
