Open AccessSpot-size converter with a SiO_2 spacer layer between tapered Si and SiON waveguides for fiber-to-chip coupling
Author(s) -
Yuriko Maegami,
Ryohei Takei,
Emiko Omoda,
Tsuyoshi Amano,
Makoto Okano,
Masahiko Mori,
Toshihiro Kamei,
Youichi Sakakibara
Publication year - 2015
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.23.021287
Subject(s) - materials science , coupling loss , optics , waveguide , optoelectronics , wavelength , coupling (piping) , silicon , optical fiber , fiber , composite material , physics
We experimentally demonstrate low-loss and polarization-insensitive fiber-to-chip coupling spot-size converters (SSCs) comprised of a three dimensionally tapered Si wire waveguide, a SiON secondary waveguide, and a SiO(2) spacer inserted between them. Fabricated SSCs with the SiO(2) spacer exhibit fiber-to-chip coupling loss of 1.5 dB/facet for both the quasi-TE and TM modes and a small wavelength dependence in the C- and L-band regions. The SiON secondary waveguide is present only around the SSC region, which significantly suppresses the influence of the well-known N-H absorption of plasma-deposited SiON at around 1510 nm.