Performance Characterization and Analytical Modelling of Electrostatic Doped Heterostructure Nanotube Tunnel Field Effect Transistor

Tunnel field-effect transistors (TFETs) face challenges in integrated circuit applications due to their low on current and ambipolar behavior, despite their steeper subthreshold slope. To enhance the on current and mitigate ambipolar conduction, heterojunction approaches are crucial, which ultimately improve the on to off current ratio of tunnel field effect transistors. This research presents an analytical model for heterostructure nanotube tunnel FETs. The model derives surface potential, capacitance, and drain current estimations by solving Poisson’s equation, incorporating both accumulation and ionized charges. These factors are also considered in the capacitance modelling to account for the effects of n-type impurity atoms in the channel. The model accounts for the combined influence of gate and drain voltages. The performance of the proposed model is validated by comparison with simulation results from Silvaco Atlas TCAD, showing impressive agreement.