Open AccessOptical characterization of extremely small volumes of liquid in sub-micro-holes by simultaneous reflectivity, ellipsometry and spectrometry
Author(s) -
Miguel Holgado,
Rafael Casquel,
Benito Sánchez,
C. Molpeceres,
M. Morales,
J.L. Ocaña
Publication year - 2007
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.15.013318
Subject(s) - refractive index , materials science , optics , ellipsometry , wafer , polarization (electrochemistry) , reflectivity , brewster's angle , refractometry , optoelectronics , thin film , chemistry , physics , nanotechnology , brewster
We have fabricated and characterized a lattice of submicron cone-shaped holes on a SiO(2)/Si wafer. Reflectivity profiles as a function of angle of incidence and polarization, phase shift and spectrometry are obtained for several fluids with different refractive indexes filling the holes. The optical setup allows measuring in the center of a single hole and collecting all data simultaneously, which can be applied for measuring extremely low volumes of fluid (in the order of 0.1 femtolitres) and label-free immunoassays, as it works as a refractive index sensor. A three layer film stack model is defined to perform theoretical calculations.