Charge-plasma-based inverted T-shaped source-metal dual-line tunneling FET with improved performance at 0.5 V operation

Abstract

In this paper, a charge plasma-based inverted T-shaped source-metal dual line-tunneling field-effect transistor (CP-ITSM-DLTFET) has been proposed to improve the ON current (ION) by increasing the line-tunneling area. In the proposed structure, the charge plasma technique is used to induce the dopants in the source and drain regions. Due to its doping-less structure, the proposed CP-ITSM-DLTFET is immune to random dopant fluctuations and does not require an expensive thermal annealing technique. This makes the proposed device’s fabrication easier and more efficient. The proposed CP-ITSM-DLTFET comprises an inverted T-shaped source metal (sandwiched between the Si-channel) and creates gate-to-source overlap and increases the tunneling area vertically on both sides of the Si-channel. The vertical line-tunneling area in the proposed structure makes the device able to be aggressively scaled compared to conventional TFETs for future technology. The proposed CP-ITSM-DLTFET outperforms almost all pre-existing dopingless TFETs in terms of DC and RF parameters. The switching performance (like high ION = 31.88 uA um−1, steeper AVSS = 23.42 mV dec−1 (over 12-order of drain current), and high ION/IOFF ratio of 1.6 × 1013) and the RF performance (like transconductance (gm) = 0.37 mS, Cut-off frequency (fT) = 90.18 GHz, and Gain Bandwidth product (GBW) = 32.3 GHz) of the proposed CP-ITSM-DLTFET are superior to almost all pre-existing Si, SiGe, and Ge based doping-less TFETs. Moreover, the proposed CP-ITSM-DLTFET-based CMOS inverter has also been comprehensively studied in the paper, showing a good noise margin NMH = 0.198 V (39.8% of VDD) and NML = 0.206 V (41.2% of VDD) with a high voltage gain of 30.25 at VDD = 0.5 V, suggesting great potential for future low power applications.