Design and Performance Analysis of Novel Single-Fin Core Shell Junctionless FinFET (CS-JL-FinFET)

Abstract Aggressive scaling of conventional field-effect transistors intensifies short-channel effects, leakage current, degraded electrostatic control and mobility-related limitations, motivating the development of alternative device architectures with improved carrier transport and gate controllability. In this work, a single-fin core-shell junctionless FinFET (CS-JL-FinFET) is proposed using three-dimensional technology computer-aided design simulations. The proposed device employs core-shell doping to modify the internal electrostatic potential, carrier distribution and gate-to-channel coupling while retaining the junctionless operating principle. A conventional single-fin JL-FinFET with identical fundamental dimensions, material system, gate work function, bias conditions and simulation methodology is employed. The electrostatic and transport characteristics are evaluated through transfer and output characteristics, potential and electric-field distributions, transconductance, output conductance, capacitance, temperature-dependent behavior, intrinsic gain, Early voltage and circuit-level inverter operation. At the nominal operating condition, the proposed CS-JL-FinFET achieves an ON-state current of \(\:{10}^{-5}\)A/µm and an OFF-state current of \(\:{10}^{-16}\)A/µm, resulting in an \(\:{I}_{on}/{I}_{off}\:\)ratio of \(\:{10}^{11}\), compared with \(\:{10}^{10}\)for the conventional JL-FinFET. The proposed device also shows a subthreshold slope of 64 mV/dec, compared with 82.7 mV/dec for conventional JL-FinFET while the peak transconductance is reported to improve by 60-67%. The enhanced current modulation by increased output conductance, resulting in lower output resistance, intrinsic gain and Early voltage than the conventional device. Resistive-load inverter shows successful voltage inversion with a 0-0.5 V input swing. These results establish core-shell doping engineering as a promising approach for enhancing the current-driving and switching characteristics of nanoscale junctionless FinFET.