Performance Analysis Of GaSb/InAs Heterojunction TFET

With the improvement of information technology and integrated circuit, the size of single semiconductor device is going to decrease and power consumption is going to increase. Meanwhile, this is the biggest obstacle to the development of integrated circuit. Tunneling Field Effect Transistors (TFETs) with different working principle are considered to solve this problem. Recently, TFETs based on band to band tunneling have been proposed as an ideal replacement of metal oxide semiconductor field effect transistors (MOSFETs) for low-power application.In this essay, we get the surface potential expression about the channel inside by solving a one-dimensional Poisson equation. The distribution of conduction band and valence band is discussed in datial.. Under the effective-mass approximation, we study the tunneling probability and the tunneling current of a GaSb/InAs heterojunction TFET by use of the Wentzen-Krammel-Brillouin (WKB) approximation. Furthermore, I discuss the effect of the gate voltage, bias and body thickness on the band to band tunneling characteristics in the heterojunction TFET. For the characteristics of a type-II heterostructure, the gate voltage will reduce the effective band gap and increase the On-current. Meanwhile, it is true that the heterojunction TFETs have obtained a subthreshold slopes steeper than the limit of the traditional metal oxide semiconductor field effect transistor (MOSFETs) for the case of a thicker body. We can conclude that the type-II heterojunction TFET show a better performance.