Silicon based antiresonant reflecting optical waveguides (ARROW's) have been designed in order to obtain a high sensitive optical transducer for sensing applications, The designed sensor has an integrated Mach-Zehnder interferometer configuration, The optical waveguides that form its structure have to verify two conditions: monomode behavior and high surface sensitivity. In this paper, we present a theoretical modeling of the propagation characteristics and surface sensitivity of the ARROW structure.