Nanjunda, A.Nikhil, K.S.2026-02-032025Silicon, 2025, , , pp. -1876990Xhttps://doi.org/10.1007/s12633-025-03574-3https://idr.nitk.ac.in/handle/123456789/20584This work presents a comprehensive investigation of GaN-based Junctionless Drain Extended Longitudinal FinFET (DELFinFET) using Sentaurus TCAD simulations, targeting thermally robust and energy efficient semiconductor devices as a means to reduce the environmental footprint of electronic devices. Introducing a longitudinal fin achieves superior lateral electric field modulation, improved carrier transport, and enhanced electric control. This helps in improving the key analog performance metrics such as sub-threshold slope, leakage current (Ioff), transconductance (gm), and the switching ratio (Ion/Ioff). The results obtained highlight the potential of DELFinFET for low-power applications. A comparative evaluation is performed between the designed device and other device configurations to verify the effectiveness of the design. © The Author(s), under exclusive licence to Springer Nature B.V. 2025.Electronic design automationEnergy efficiencyFinFETGallium nitrideLeakage currentsLow power electronicsSemiconductor device modelsSemiconductor junctionsThermal management (electronics)Thermoelectric equipmentWide band gap semiconductorsDrain extended longitudinal FinFETElectronics applicationsFinFETsGaN basedLow PowerPerformanceSustainable electronicsTCADTCAD simulationThermal-AwareIII-V semiconductors