Chen Shupeng, Liu Hongxia, Wang Shulong, Li Wei, Wang Xing, Zhao Lu
School of Microelectronics, Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices of Education, Xidian University, Xi'an, 710071, China.
Nanoscale Res Lett. 2018 Oct 12;13(1):321. doi: 10.1186/s11671-018-2723-y.
In this paper, a silicon-based T-shape gate dual-source tunnel field-effect transistor (TGTFET) is proposed and investigated by TCAD simulation. As a contrastive study, the structure, characteristic, and analog/RF performance of TGTFET, LTFET, and UTFET are discussed. The gate overlap introduced by T-shape gate can enhance the efficiency of tunneling junction. The dual-source regions in TGTFET can increase the on-state current (I) by offering a doubled tunneling junction area. In order to further improve the device performance, the n+ pocket is introduced in TGTFET to further increase the band-to-band tunneling rate. Simulation results reveal that the TGTFET's I and switching ratio (I/I) reach 81 μA/μm and 6.7 × 10 at 1 V gate to source voltage (V). The average subthreshold swing of TGTFET (SS, from 0 to 0.5 V V) reaches 51.5 mV/dec, and the minimum subthreshold swing of TGTFET (SS, at 0.1 V V) reaches 24.4 mV/dec. Moreover, it is found that TGTFET have strong robustness on drain-induced barrier lowering (DIBL) effect. The effects of doping concentration, geometric dimension, and applied voltage on device performance are investigated in order to create the TGTFET design guideline. Furthermore, the transconductance (g), output conductance (g), gate to source capacitance (C), gate to drain capacitance (C), cut-off frequency (f), and gain bandwidth (GBW) of TGTFET reach 232 μS/μm, 214 μS/μm, 0.7 fF/μm, 3.7 fF/μm, 11.9 GHz, and 2.3 GHz at 0.5 V drain to source voltage (V), respectively. Benefiting from the structural advantage, TGTFET obtains better DC/AC characteristics compared to UTFET and LTFET. In conclusion, the considerable good performance makes TGTFET turn into a very attractive choice for the next generation of low-power and analog/RF applications.
本文提出了一种基于硅的T形栅双源隧道场效应晶体管（TGTFET），并通过TCAD模拟对其进行了研究。作为对比研究，讨论了TGTFET、LTFET和UTFET的结构、特性以及模拟/射频性能。T形栅引入的栅极重叠可以提高隧道结的效率。TGTFET中的双源区通过提供两倍的隧道结面积来增加导通电流（I）。为了进一步提高器件性能，在TGTFET中引入了n+口袋以进一步提高带间隧穿速率。模拟结果表明，在栅源电压（V）为1 V时，TGTFET的I和开关比（I/I）分别达到81 μA/μm和6.7×10。TGTFET的平均亚阈值摆幅（SS，从0到0.5 V V）达到51.5 mV/dec，最小亚阈值摆幅（SS，在0.1 V V时）达到24.4 mV/dec。此外，发现TGTFET对漏极感应势垒降低（DIBL）效应具有很强的鲁棒性。研究了掺杂浓度、几何尺寸和外加电压对器件性能的影响，以制定TGTFET的设计准则。此外，在漏源电压（V）为0.5 V时，TGTFET的跨导（g）、输出电导（g）、栅源电容（C）、栅漏电容（C）、截止频率（f）和增益带宽（GBW）分别达到232 μS/μm、214 μS/μm、0.7 fF/μm、3.7 fF/μm、11.9 GHz和2.3 GHz。得益于结构优势，与UTFET和LTFET相比，TGTFET具有更好的直流/交流特性。总之，TGTFET相当出色的性能使其成为下一代低功耗和模拟/射频应用中极具吸引力的选择。
