Design of optical single mode splitter using ion exchange method for ammonia biosensor

One reasonable and cost-effective method to sense chemicals such as ammonia is to use optical waveguides. In this work, the simulation of an optical single-mode splitter waveguide was executed to detect ammonia on the sensing arm. OptiBPM and Ionex softwares were used for the waveguide and ion exchange simulations respectively. The deepest and widest optical channel was produced when a concentration of Ag⁺ of 0.2 moles/m³ was used at a temperature of 350°C for duration of 35 minutes. The optical splitter designed in OptiBPM showed a change in the optical power with the presence of ammonia on the gold-coated sensing arm of the splitter. Therefore, the thermal ion change method is an alternative cost-effective method for the fabrication of optical biosensors.