Open AccessStudy of optical anisotropies in benzocyclobutene thin films for the efficient design of optical waveguide devices
Author(s) -
Md. Foisal Hossain,
Hau Ping Chan,
M. A. Uddin
Publication year - 2010
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.18.008896
Subject(s) - benzocyclobutene , materials science , anisotropy , refractive index , isotropy , thin film , optics , polarization (electrochemistry) , substrate (aquarium) , thermal expansion , waveguide , stress (linguistics) , thermal oxidation , optoelectronics , composite material , silicon , chemistry , nanotechnology , dielectric , linguistics , physics , oceanography , philosophy , geology
We study the in-plane/out-of-plane anisotropies in refractive indices (n) and in thermo-optic coefficients (dn/dT) of benzocyclobutene (BCB) thin film on a substrate. Both nonoxidized and oxidized films are investigated. Aside from the stress-induced effects, oxidation has significant influence on the refractive index anisotropy. The dependence of the anisotropy on each of the thermal stress and the oxidation is determined quantitatively. The anisotropies in the dn/dT values are mainly caused by the thermal stress and are independent of oxidation. However, the original (stress-free) thermo-optic coefficients are obtained as isotropic and significantly different than the measured dn/dT values. Our findings have the potential to optimize the design of polarization insensitive and/or athermal BCB optical waveguide devices.