Impact of interface charges on the performance of Dual Material Double Gate tunnel FET

In this work, effect of interface charge on the performance of a Dual Material Double Gate (DMDG) Tunnel Field Effect Transistor (TFET) device has been studied. Due to the presence of high electric field in the device, interface charges are generated at oxide-semiconductor interface by hot carrier effect. A 2-D model of the device with interface charge has been developed in TCAD simulator and impact of both positive and negative interface charges has been observed in potential distribution, band profile, carrier concentration, tunneling current and threshold voltage. Since high electric field mainly exists in the source-body junction of the device, interface charges are mainly localized at that region. Effect of localized charge spreading over varying length has also been analyzed on surface potential and threshold voltage of the device. The study will be useful in fabrication and application of DMDG TFET devices.