Four layer configuration in enhancing sensitivity of Directional Coupler for Bio-medical Application

In this paper we propose a four layer configuration of Inegrated optical (IO) device-based Directional Couplers biosensors to increase coupling efficiency and sensitivity of directional coupler. The novelty of the configuration is insertion of additional Silicon Nitride layer between Silicon and Silicon dioxide. The insertion of thin Silicon Nitride reduce index contrast which enhances the penetration of guided mode into the cladding bio analyte for improving ation by considering Ridge waveguide and achieve high Sensitivityof DC In S-bend DC biosensor the S-bend impact power flow so it is necessary to consider it while evaluating the coupling. So in this paper proposed a Variational Hybrid method approach for evaluating the coupling coefficient and the Power coupled as conventional method not wel suited for four layer analysis due to lack of considering geometry like S-bend effect in coupling.