Insight into the Output Characteristics of III-V Tunneling Field Effect Transistors
The mechanism of the drain current saturation in the output characteristics of a III-V tunneling Field Effect Transistor (TFET) is explained in detail using numerical simulations as well as physics-based analytical models. We clearly identify impact of the source doping on delayed output saturation, and non-linear turn on behavior observed in the output characteristics of TFETs. Our model uses Wentzen-Krammel-Brillouin (WKB) approximation and considers the exponentially decaying potential profile in the channel. The choice of source doping in a III-V p-channel TFET requires tradeoff between maintaining steep switching and delayed saturation voltage which is of importance for complementary TFET logic.