Impact of drain doping engineering on ambipolar and high-frequency performance of ZHP line-TFET

Abstract

In this paper, we present a new Z-shaped line tunnel field effect transistor (TFET) employing drain doping engineering with a split drain structure (SD-ZHP-TFET). The split drain (SD) approach in the proposed ZHP-TFET helps increasing tunneling width at the channel-drain interface, reducing ambipolarity. Moreover, a horizontal pocket (HP) is implanted in the source region to boost the ON-current of the proposed SD-ZHP-TFET structure. The effect of both these approaches in the line-TFET provides higher ON-current and reduces ambipolarity significantly. Split drain structure in the ZHP-TFET exhibits a three-decade improvement in the ambipolar current without affecting the subthreshold (SS) and leakage current significantly. A calibrated simulation study of split drain thickness (t u ) and drain region doping variation on the analog performance are investigated using the technology computer-aided design device simulator. Moreover, the high-frequency figure of merit regarding total gate capacitance (C gg ), unit-gain cut-off frequency (f T ) is analysed. It is found that the drain doping improves the cut-off frequency from 1.8 GHz in ZHP-TFET to 2.2 GHz in the proposed SD-ZHP-TFET structure. Thus the proposed device is capable of providing higher I ON /I OFF (≈10 13 ) and I ON /I AMB (≈10 13 ) ratio with an average SS of 44 mV/decade.

DC and RF/analog parameters in Ge‐source split drain‐ZHP‐TFET: Drain and pocket engineering technique

“…The 2D schematic of the Ge-source SD-ZHP-TFET is shown in Figure 1(A) and this architecture is similar to existing literature. 31 The 2D view of SD-ZHP-TFET and ZHP-TFET are portrayed in Figure 1(B,C), respectively. It is well known that the energy bandgap of Ge is comparatively lower as compared to Si material.…”

“…The dimensions of t r1 and t r2 are equal and it is denoted by t u . A large of number of TFET structures with gate oxide thickness of 1 and 2 nm are reported 21,24,31 in literature. Accordingly, in this work a gate oxide thickness of 1 nm is considered for Ge-source SD-ZHP-TFET.…”

“…30 The electrical characteristics of line TFET is reported experimentally by Der Agopin et al 27 Recently, a split-drain Z-shaped horizontal pocket (HP) TFET is highlighted in literature to minimize the ambipolar current with improved ON current. 31 Also, the SD-ZHP-TFET has significant improvement in subthreshold characteristic.…”

Analysis on effect of lateral straggle on analog, high frequency and DC parameters in Ge‐source DMDG TFET

“…19 Nawal and Chauhan reported that TFET with hetero dielectric BOX has improved RF and analog behavior compared to conventional TFET. 20 Likewise, the RF/analog characteristic of a Z shape line TFET (ZS-TFET) having split drain engineering is examined through TCAD simulator 21 and TFET with split drain has improved cut-off frequency compared to ZS-TFET. On the other hand, the fabrication of non-traditional TFET architecture is a very critical job.…”

Segmented Drain Engineered Tunnel Field Effect Transistor for Suppression of Ambipolarity

“…Tunnel FET is one of the evolving energy-efficient devices to substitute bulk MOS in the low supply voltage regime due to its capability to achieve a sub-60 mV/decade inverse subthreshold slope in room temperature [1][2][3][4][5][6]. The TFET devices heavily rely on the interband tunneling mechanism for its carrier transportation and thus exhibit improved switching characteristics at ultra-low supply voltage [1,2].…”