Open AccessLow loss (~6.45dB/cm) sub-micron polycrystalline silicon waveguide integrated with efficient SiON waveguide coupler
Author(s) -
FengLing Qing,
Jun-Feng Song,
Shaohua Tao,
Mingbin Yu,
G. Q. Lo,
D. L. Kwong
Publication year - 2008
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.16.006425
Subject(s) - materials science , optics , waveguide , coupling loss , cladding (metalworking) , refractive index , insertion loss , power dividers and directional couplers , transmission loss , optoelectronics , optical fiber , silicon , physics , metallurgy
In this communication, the sub-micron size polycrystalline silicon (poly- Si) single mode waveguides are fabricated and integrated with SiON waveguide coupler by deep UV lithography. The propagation loss of poly-Si waveguide and coupling loss with optical flat polarization-maintaining fiber (PMF) are measured. For whole C-band (i.e., lambda approximately 1520-1565nm), the propagation loss of TE mode is measured to approximately 6.45+/-0.3dB/cm. The coupling loss with optical flat PMF is approximately 3.4dB/facet for TE mode. To the best of our knowledge, the propagation loss is among the best reported results. This communication discusses the factors reducing the propagation loss, especially the effect of the refractive index contrast. Compared to the SiO(2) cladding, poly-Si waveguide with SiON cladding exhibits lower propagation loss.