Analytical study of dual-material gate inverted T-TFET biosensor for ultra-sensitive detection

Tunnel field effect transistors (TFETs) have shown significant promise in the context of analog and mixed-signal circuit applications because of their high on-state current, low off-state leakage. As devices are being scaled down further in dimensions, conventional devices face severe short-channel effects (SCE), which have a detrimental impact on device characteristics. To overcome these issues, a variety of novel devices have been explored in recent years. Among these devices, the Dual Metal Gate T-shaped TFET biosensor device has shown promise in terms of electrostatic control and SCE suppression. An analytical model of a Dual Metal Gate T-shaped TFET biosensor device has been proposed in the present work with the aim of investigating the characteristics of the device. To obtain an analytical expression of the surface potential, threshold voltage, electric field, and sensitivity and drain current of the device, the two-dimensional Poisson equation has been solved with suitable boundary conditions using a parabolic potential approximation. The inverted T-shape of the TFET device ensures low power operation and high sensitivity in the subthreshold regime. Also, the device exhibits the ability of biosensing without the need for labeling.