Effect of Interface Traps and Oxide Charge on Drain Current Degradation in Tunneling Field-Effect Transistors

In this letter, we report for the first time the degradation mechanism of drain current in tunneling field-effect transistors (TFETs). Using positive-bias and hot-carrier (HC) stress experiments and TCAD simulation, we show that the drain current degradation is mainly induced by the interface traps and/or oxide charge located above the tunneling region, causing reduction of tunneling field and tunneling current. The interface traps mainly induce the degradation in transconductance, while the oxide charge essentially causes a threshold-voltage shift in TFETs. The results show that the interface-trap generation is dominant under a positive-bias stress, while the oxide-charge creation is important under an HC stress in n-TFETs.