Linearity Performance and Distortion Analysis of Carbon Nanotube Tunneling FET

In this research work, we have varied several parameters of a carbon nanotube based tunneling field effect transistor (CNT-TFET) such as the dielectric constant of the gate insulator (κ), channel length, oxide thickness, doping level, and the nature of doping to investigate how the performance of the CNT-TFET is affected. The performance analysis has been done based on the following performance criteria: Subthreshold swing (SS), threshold voltage (V_T), and on-current to off-current ratio (I_on/I_off). In addition, we have also analyzed how linearity and distortion figures of merit such as second-order voltage intercept point (VIP2), third-order voltage intercept point (VIP3), third-order input intercept point (IIP3), and third-order intermodulation distortion (IMD3) are affected by parametric variation. By observing the impact of parametric variation on this large number of performance metrics, a compromise choice of structural parameters is possible depending on the application. Moreover, we have proposed an asymmetric doping design that suppresses the highly undesirable ambipolar behavior in CNT-TFET. In a real-space approach, the simulation study has been carried out using the elegant non-equilibrium Green’s function (NEGF) formalism considering tight-binding Hamiltonian.