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Standard-cell design, technology choices, and place and route (P&R) efficiency are deeply interrelated in CMOS technology nodes below 10 nm, where lower number of tracks cells and higher pin densities pose increasingly challenging problems to the router in terms of congestion and pin accessibility. To evaluate and downselect the best solutions, a holistic design-technology co-optimization approach leveraging state-of-theart P&R tools is thus necessary. We adopt such an approach using the imec N7 technology platform, with contacted poly pitch of 42 nm and tightest metal pitch of 32 nm, by comparing post P&R area of an IP block for different standard cell configurations, technology options, and cell height. Keeping the technology node and the set of ground rules unchanged, we demonstrate that a careful combination of these solutions can enable area gains of up to 50%, comparable with the area benefits of migrating to another node. We further demonstrate that these area benefits can be achieved at isoperformance with >20% reduced power. As at the end of the CMOS roadmap, conventional scaling enacted through pitch reduction is made more and more challenging by constraints imposed by lithography limits, material resistivity, manufacturability, and ultimately wafer cost, the approach shown herein offers a valid, attractive, and low-cost alternative. [ABSTRACT FROM AUTHOR]

A novel sub-threshold 9 T Static Random Access Memory (SRAM) cell designed and simulated in 14-nm FinFET technology is proposed in this paper. The proposed 9 T-SRAM cell offers an improved access time in comparison to the 8 T-SRAM cell. Furthermore, an assist circuit is proposed by which the leakage current of the proposed SRAM cell is reduced by 20% when holding '0' and an equal leakage current during hold '1' in comparison to the 8 T-SRAM cell. The proposed circuit improves the access time by 40% in comparison to the 8 T-SRAM cell without any degradation in write and read noise margins, as well. The maximum operating frequency of the proposed SRAM cell is 1.53 MHz at VDD = 270 mV. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Standard-cell design and characterization are presented for 7-nm CMOS platform technology targeting low-power and high-performance applications with the tightest contacted poly pitch of 42 nm and a metallization pitch of 32 nm in the FinFET technology. Two standard-cell architectures for 7 nm, a 9-track library and a 7.5-track library have been designed, introducing an extra middle-of-line layer to enable an efficient layout of the 7.5-track cells. The 7.5-track cells are on average smaller than the 9-track cells. With the strict design constraints imposed by self-aligned quadruple patterning and self-aligned double patterning, careful design and technology co-optimization is performed. [ABSTRACT FROM AUTHOR]

For the first time, we present complete device threshold voltage (VT)-targeting methodology for FinFET SRAM in 10-nm technology, considering capacitance due to metal pattering and device variability to set target read current for different variants of SRAM architecture to determine technology high-density (HD) SRAM cell. The VT-targeting methodology brings into play the worst case read and write margins available for SRAM cell to determine nominal device VT by tuning the work function of metal gate. Analysis shows that for minimum leakage current, 112 SRAM cell is optimum, whereas for the same area of 0.0546~\mu \mathrm{m}^{\mathrm {2}} with 50% higher leakage, 122 SRAM outperform by 5% and 20% improved read and write margins, respectively. The 122 SRAM as HD cell reduces the cost of the technology by sharing P-channel field effect transistor (PFET) and N-channel field effect transistor (NFET) VT mask with the high threshold voltage logic devices, whereas the 112 SRAM device shares only NFET VT mask. The 111 SRAM can achieve target performance at lesser area of 0.048~\mu \mathrmm^\mathrm 2 by compromising read stability, which will result in lower yield. At 64-nm pitch, litho-etch litho-etch (LELE) double-patterned gate impacts device performance and alleviates variability; hence the read margin of SRAM cell should consider an additional 1\sigma \mathrm {\mathbf {rsnm}} margin to retain the same yield in 10-nm-technology era. [ABSTRACT FROM AUTHOR]

We propose a bilayer graphene (BLG) tunneling field-effect-transistor (TFET) suitable for digital CMOS logic circuits. The ultimate performance limit of this structure is evaluated by solving the quantum transport equations in nonequilibrium Green’s function framework. A bandgap opening is induced in BLG using both vertical electric field and top–bottom asymmetric chemical doping. To overcome the limitations of nonabrupt p-i-n junctions using practical process methods, source/drain regions are created using work-function engineered metal-graphene contacts. We evaluate the performance of BLG-TFET by taking doping gradient due to contact induced doping into account. Our BLG-TFET exhibits a subthreshold slope as low as 35 mV/dec, and I\mathrm{{\scriptstyle ON}}/I\mathrm{{\scriptstyle OFF}} as high as 2910 for a supply voltage of 0.2 V. The proposed BLG-TFET shows promise for ultralow-power applications, particularly in low to medium speed applications. [ABSTRACT FROM AUTHOR]

Abstract: In deeply scaled CMOS technologies, Bias Temperature Instability (BTI) is one of the most critical degradation mechanisms impacting the device reliability. This study presents the BTI evaluation of gates covering both the PMOS and NMOS degradation in a workload dependent, atomistic trap-based, stochastic BTI model. The gate propagation delay depends on the gate intrinsic delay, the input signal characteristics, and the output load. In this paper, the impact of (1) duty factor, (2) periodic clock-based and non-periodic random input sequences, (3) gate, and (4) drive strength to the BTI degradation are investigated. Statistical studies show a mean degradation of 3% and a worst-case of 27%. Moreover, the near-critical paths with lower drive strength cells are 3.7× more susceptible to BTI degradation than the critical paths with higher drive strength cells. Next, the relative degradations of the propagation delays for the well-known gates (i.e. INV, NAND, NOR, AOI) are presented. Under the same stress stimuli, degradations of the gate propagation delays differ by 4.5×. [Copyright &y& Elsevier]