A high performance 180 nm generation logic technology

Carbon nanotube (CNT)-based electronics are a potential candidate to replace silicon complementary metal-oxide-semiconductor (CMOS) technology, which will soon meet its performance limit at the 7 or 5 nm technology node 1,2 . Prototype device studies using individual CNTs have shown that nanotube electronics have the potential to outperform Si CMOS technology in both performance and power consumption [3][4][5][6] , and are even close to the theoretical limits for all field-effect-transistor(FET)-based binary switches 7,8 . Recently, FETs were fabricated using aligned CNT arrays, and shown to have a higher channel conductance (at a lower bias) than that of Si CMOS FETs 9 . However, the key performance metrics reported for such CNT FETs, including on-state current density (I on ) and transconductance (g m ), are still substantially lower than those of conventional Si CMOS FETs at the same characteristic length [9][10][11][12][13] . The ideal material system for high-performance CNT electronics has been identified as a parallel array film of intrinsic pure semiconductor single-walled nanotubes of a single chirality with a diameter of approximately 1.3 nm and no defects, and a tube-tube spacing of 5-8 nm (ref. 14 ). Although such an ideal material system is yet to be realized, many breakthroughs in the purification and controlled synthesis of CNTs have been made in recent years [15][16][17][18][19] , suggesting the possibility of achieving the required nanotube purity and array density before 2020 14 . Using randomly oriented or aligned CNT array films, various types of CNT thin-film FETs have been fabricated [9][10][11][12][13] . However, hindered by the limited performance of nanotube FETs, the operation speed of CNT integrated circuits (ICs) 20-31 typically falls short of their expected terahertz potential, and that achieved by Si CMOS circuits (gigahertz), by several orders of magnitude. Notably, CNT-based ring oscillators (ROs) with an oscillation frequency (f o ) of 282 MHz have recently been reported 32 . However, CNT-thin-film-based ICs typically have a working frequency of less than 1 MHz, which might be useful for flexible electronics, but is not suitable for mainstream high-performance CMOS technology 33 . In this study, we used a randomly oriented CNT film to build CNT FETs and ICs, fabricating, in particular, five-stage ROs with f o of up to 5.54 GHz. The random CNT film is essentially the same as a network film, but here we used the term 'random film' to emphasize that our FETs are contact dominated and have a different transport mechanism to that of junction-dominated network-type FETs 34,35 . In principle, aligned CNT arrays would provide better device performance, but it remains a challenge to obtain wafer-scale aligned CNT arrays with high uniformity, high density and high semiconductor purity for constructing high-performance ICs. Although it is not the ideal scheme, the FET-and IC-based random CNT film can nevertheless provide a feasible demonstration to assess the floor-level performance (f...

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“…39 ), and is even comparable to the gate delay of commercial Si CMOS ICs (τ = 11 ps) with a L g of 130 nm (ref. 40 , Fig. 3e).…”

Section: Nature Electronicsmentioning

confidence: 91%

Gigahertz integrated circuits based on carbon nanotube films

et al. 2017

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“…The stress in n-MOSFETs does not increase the v inj as in the p-MOS devices, consequently the stress-induced I ON improvements are larger in p-MOS transistors than in n-MOS ones [78]. [54,56,57,[92][93][94][95][96][97][98][99] Quite interestingly, the simulation prediction of a stressinduced improvement of the I ON disadvantage of pMOSFETs is supported by the experimental data. In fact Fig.…”

Section: Simulation Results For Nano-scale Mosfetsmentioning

confidence: 84%

Semi-classical transport modelling of CMOS transistors with arbitrary crystal orientations and strain engineering

et al. 2009

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This paper reviews the basic methodologies and models used in the semi-classical modelling of CMOS transistors in the framework of the nowadays generalized scaling scenario. The capabilities to describe devices with arbitrary crystal orientations and strain configurations are discussed. Several simulation results are illustrated and compared to the experiments to assess the understanding of the underlying physics and the predictive capabilities of the models. A case study concerning the drain currents in nano-scale uniaxially strained MOSFETs is presented and it shows how the strain engineering may change the traditional on-current disadvantage of the p-MOS compared to the n-MOS transistors.

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“…The core is implemented in an n-well on P-epi 0.18-m lithography process similar to that described in [1]. This process implements a 5% optical shrink from that process, as well as numerous changes to both the transistors and interconnect to support SOC applications.…”

Section: Process Technologymentioning

confidence: 99%

Section: Process Technologymentioning

confidence: 99%