InGaAs-based tunneling field-effect transistor with stacked dual-metal gate with PNPN structure for high performance

We have proposed an InGaAs-based gate-all-around (GAA) tunneling field-effect transistor (TFET) with a stacked dual-metal gate (DMG). The electrical performances of the proposed TFET are evaluated through technology computer-aided design (TCAD) simulations. The simulation results show that the proposed TFET demonstrates improved DC performances including high on-state current (I_on) and steep subthreshold swing (S), in comparison with a single-metal gate (SMG) TFET with higher gate metal workfunction, as it has a thinner source-channel tunneling barrier width by low workfunction of source-side channel gate. The effects of the gate workfunction on I_on, the off-state current (I_off), and S in the DMG-TFETs are examined. The DMG-TFETs with PNPN structure demonstrate outstanding DC performances and RF characteristics with a higher n-type doping concentration in the In_0.8Ga_0.2As source-side channel region.