This study introduces a biosensor employing a dielectric-modulated dual material gate tunnel field effect transistor (DM-DMG TFET) in 10 nanometer technology. To detect diverse bio molecules, the biosensor incorporates a nano gap cavity formed through gate overlap on the drain side. The variation in ambipolar current serves as the sensing parameter, influenced by altering the dielectric constants of immobilized bio molecules within the nano cavity. In this paper, the simulation results of biosensor employing a dielectric-modulated dual material gate tunnel field effect transistor with different dielectric constants imposed in nano cavity. A comprehensive examination of the biosensor's performance is conducted, exploring various positions and filling factors of bio molecules within the nano cavity region. This analysis involves a thorough investigation into the device's performance, considering a range of parameters such as drain current, electric field distribution, variations in surface potential, configurations of energy bands, behaviors of carrier concentration, and the Ion/Ioff ratio. The simulations are done using the Silvaco TCAD Atlas tool. © 2024 The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, as long as the original authors and source are cited. No permission is required from the authors or the publishers.