Charge-plasma based symmetrical-gate complementary electron–hole bilayer TFET with improved performance for sub-0.5 V operation

Abstract

In this paper, the complementary charge-plasma (CP) based symmetrical-gate electron-hole bilayer (EHB) Tunnel Field-Effect Transistor (TFET) at a low operating voltage (≤0.5V) is introduced. Where, by using CP technique, the source/drain & EHB-channel is induced by depositing metal electrode with appropriate work function. Moreover, the immunity against random dopant fluctuations and the feasibility of a self-aligned process due to a symmetrical top/bottom gate arrangement without the need for a high thermal annealing process make the fabrication of the proposed EHB-TFET very reliable and efficient. Moreover, by implementing the Density Gradient Quantum Correction Model, the quantum confinement and its effect on confining the 2D electron-hole concentration are also corrected as the proposed device has a smaller channel thickness of 5 nm. The proposed device shows superior performance against almost all Si-based CP-TFETs with a higher ON-current of 47.33μA/μm, a smaller average subthreshold swing of 13.53mV/dec and a high ON-current to OFF-current ratio of 2.16×1013. This indicates that the proposed device is a promising candidate for future low-power applications

Undoped vertical dual-bilayer TFET with a super-steep sub-threshold swing: proposal and performance comparative analysis

“…Due to the asymmetric top-and-bottom gate architecture present in the structure. As a result, in our previous work [20],…”

“…In which [16][17][18][19] are some examples that focus on improving the conduction by aligning the tunnelling direction parallel to gate field also known as so called line tunnelling. Among these, the recently proposed electron-hole bilayer TFET (EHB-TFET) [20][21][22] has been very well received by the research community. It basically exploits the line tunnelling or tunnelling aligned to the gate field through the formation of the 2D-biasinduced EHB [21][22][23].…”

“…we successfully attempted to overcome the fabrication complexities of conventional EHB-TFETs by employing symmetric top and bottom gate architectures as well as implementing the charge plasma concept in our novel device known as the charge plasma-based symmetrical gate electron-hole bilayer TFET (CP-SG-EHB-TFET) [20]. The symmetrical gate architecture in our CP-SG-EHBTFET [20] makes the device easy to fabricate due to its feasibility in the self-aligned process, and the implementation of the charge plasma concept gives several benefits, such as the ability to resolve the problem of random dopant fluctuation, removing the need for high thermal budgeting, and making the fabrication process simpler at a reduced cost.…”

“…we successfully attempted to overcome the fabrication complexities of conventional EHB-TFETs by employing symmetric top and bottom gate architectures as well as implementing the charge plasma concept in our novel device known as the charge plasma-based symmetrical gate electron-hole bilayer TFET (CP-SG-EHB-TFET) [20]. The symmetrical gate architecture in our CP-SG-EHBTFET [20] makes the device easy to fabricate due to its feasibility in the self-aligned process, and the implementation of the charge plasma concept gives several benefits, such as the ability to resolve the problem of random dopant fluctuation, removing the need for high thermal budgeting, and making the fabrication process simpler at a reduced cost. In our previous CP-SG-EHBTFET [20] work, we successfully demonstrated and comparatively analysed (against the bottom gate bias) that, without the need of bottom gate bias or a floating bottom gate, the p + hole region at the bottom layer can be induced by the help of charge plasma with the platinum metal (having a workfunction of 5.93 eV) for successful operation of the EHB TFET.…”

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

“…It is worth noting that there are various studies in the literature that adopt the semiclassical, self-consistent Schrödinger-Poisson solver with the density gradient model for quantum confinement and the WKB approximation-based non-local band-to-band tunnelling model to calculate tunneling currents. Our study follows a similar approach [67][68][69][70][71][72][73][74]. However, it is important to emphasize that these studies take a qualitative simulation approach, primarily focusing on analyzing the behavior and characteristics of the proposed device based on its underlying physical principles without necessarily quantifying its performance.…”