Effect of Ge Mole Fraction on Performance of Underlapped Gate-All-Around SiGe-Source Tunneling Field-Effect Transistors

In this paper, we propose the design optimization of underlapped Si1–xGex-source tunneling field-effect transistors (TFETs) with a gate-all-around structure. The band-to-band tunneling rates, tunneling barrier widths, I–V transfer characteristics, threshold voltages, on/off current ratios, and subthreshold swings (SSs) were analyzed by varying the Ge mole fraction of the Si1–xGex source using a commercial device simulator. In particular, a Si0.2Ge0.8-source TFET among our proposed TFETs exhibits an on/off current ratio of approximately 1013, and SS of 27.4 mV/dec.

Study on Single Event Effect Simulation in T-Shaped Gate Tunneling Field-Effect Transistors

Tunneling field-effect transistors (TFETS) can reduce the subthreshold swing (SS) to below 60 mV/decade due to their conduction mechanism with band-to-band tunneling (BTBT), thereby reducing power consumption. T-shaped gate tunneling field-effect transistors (TGTFET) adapt double source and T-shaped gates to enhance the on-state current and to generate the tunneling probability. In this paper, TGTFET subjected to heavy-ion irradiation is studied by technology computer-aided design (TCAD) simulation for the first time. The results show that as the drain bias and linear energy transfer (LET) increase, the transient current and collected charge also increase. When LET = 100 MeV·cm2/mg and Vd = 0.5 V, the transient current of TGTFET is as high as 10.63 mA, which is much larger than the on-state current. This means that TGTFET is more sensitive to single-event effect (SEE) than FDSOI. By simulating a heavy-ion strike on different locations in TGTFET, the tunneling junction is the most sensitive region of SEE. This provides guidance for future research on the antiradiation application of TFET-based devices.