Oxide-Trapped-Charge-Induced Gate-Diagonal Tunneling Suppression of Gate-Normal Tunnel Field-Effect Transistors

We analyze the suppression of gate-diagonal tunneling by an oxide-trapped charge in gate-normal tunneling field effect transistors (TFETs). It is observed that the gate-diagonal tunneling occurring ahead of gate-normal tunneling can be alleviated by trapping electrons in the gate insulator over the channel region. Oxide-trapped charges can be generated by process technologies or hot carrier injections. Because the trapped electrons screen the gate voltage effectively and weaken the gate controllability over the gate-diagonal tunneling region, the achieved subthreshold swing and on-current are 27-% lower and 2.89x higher than those of conventional gate-normal TFETs, respectively.