Query: FINFET versus pass transitor

Candidate papers:

abstract: This work examines the metal ferroelectric insulator semiconductor (MFIS) negative capacitance FinFET (NC FinFET) based VLSI subsystem level logic circuits. With the aid of a short channel NC FinFET compact model, we confirm the functionality and determine the standby power/switching energy/delay performance of logic circuits (5 stage inverter and 4 bit Manchester carry chain (MCC) adder) employing 14nm ULP NC FinFETs versus FinFETs. We show that the inverse $V_{ds} dependency of threshold voltage (V_{T} also known as the negative DIBL, of NCFET is not only acceptable but also beneficial for the speed performance of both the static and pass transistor logic (PTL) circuits, especially for the PTL at low $V_{DD}
author_names: Wei-Xiang You

Pin Su

Chenming Calvin Hu
title: Evaluation of NC FinFET Based Subsystem Level Logic Circuits Using SPICE Simulation
venue: 2018 IEEE SOI 3D Subthreshold Microelectronics Technology Unified Conference (S3S)
year: 2018

abstract: SRAM plays an integral role in the power, performance, and area of a mobile system on a chip. To achieve low power and high density, extreme ultraviolet (EUV) technology is adopted for the 7nm FinFET technology [3 4] Conventional ArF immersion with a single exposure for an extreme high resolution patterning shows the limitation of lithographic patterning. Therefore, multi patterning lithographic technique is applied to support a high resolution lithography. However, this also includes process variations due to using multi pattering masks. Alternatively, EUV offers competitive scaling with a single mask with the benefit of smaller wavelength, which provides smaller process variation with less additional pattering. Figure 11.2.1 shows a 7nm EUV FinFET 6T high density (HD) SRAM bitcell with an area of 0.026msi2. The pull up, pass gate, and pull down ratios are 1:1:1 for high density and low power applications. Another benefit of EUV technology also features a bi directional metal layer with a scaled pitch that provides an extra degree of freedom for signal and power routing. Figure 11.2.2 highlights EUV benefits in accordance with bi directional metals. A uni directional metal layer requires different metal layer to connect two nets, and have no choice but to support the limited via between two perpendicular metal lines with the limited metal width. A wider metal allows placement of more vias between the metal lines, but it does not demonstrate optimum Power, Performance, and Area (PPA) with redundant parasitic capacitance. However, EUV provides bi directional metal lines, where the different layers of metal are coherent in the same direction. Therefore, more vias can be placed to reduce the IR drop with smaller parasitic capacitance and resistance. Figure 11.2.2 illustrates the delay impact versus stacked via distance in a standard cell array. It shows that the timing penalty is directly proportional to the stacked via distance in a uni directional metal routing.
author_names: Taejoong Song

Jonghoon Jung

Woojin Rim

Hoonki Kim

Yongho Kim

Changnam Park

Jeongho Do

Sunghyun Park

Sungwee Cho

Hyuntaek Jung

Bongjae Kwon

Hyun-Su Choi

Jaeseung Choi

Jong Shik Yoon
title: A 7nm FinFET SRAM using EUV lithography with dual write driver assist circuitry for low voltage applications
venue: 2018 IEEE International Solid State Circuits Conference (ISSCC)
year: 2018

abstract: A 16nm configurable pass gate bit cell register file allows a direct comparison of NFET versus PFET pass gate bit cells for early technology evaluation. The configurable pass gate enables either a transmission gate (TG) an NFET pass gate, or a PFET pass gate. From silicon test chip measurement, the register file with PFET pass gate bit cells achieves a 33% minimum supply voltage (VMIN) reduction in a 16nm FinFET technology and a 40% VMIN reduction in an enhanced 16nm FinFET technology as compared to a register file with NFET pass gate bit cells. Test chip measurements highlight the superior benefits of the PFET drive current relative to the NFET drive current at low voltages. The VMIN improvement with a PFET pass gate bit cell represents a paradigm shift from traditional CMOS circuit design practices.
author_names: Jihoon Jeong

Francois Atallah

Hoan Nguyen

Josh Puckett

Keith A Bowman

David Hansquine
title: A 16nm configurable pass gate bit cell register file for quantifying the VMIN advantage of PFET versus NFET pass gate bit cells
venue: 2015 IEEE Custom Integrated Circuits Conference (CICC)
year: 2015

abstract: BACKGROUND AND PURPOSE Subclinical hepatic encephalopathy (SHE) is frequently reported on single photon emission computed tomography (SPECT) but is rarely described with magnetic resonance (MR) techniques. This study aimed to investigate hemodynamic changes in brain basal ganglia in patients with SHE using dynamic susceptibility contrast (DSC) enhanced MR perfusion imaging. METHODS Twelve patients with SHE and ten age and education matched volunteers agreed to undergo MR examination. The scanning protocol included conventional anatomical images and DSC enhanced perfusion MR imaging. Using MGH perfusion software, parameter maps of cerebral blood flow (CBF) cerebral blood volume (CBV) and mean transit time (MTT) were created. The bilateral caudate nucleus head, globus pallidus, putamen and thalamus were selected as regions of interest (ROI) with ipsilateral white matter of the frontal lobe used as reference. Ratios (ROI versus ipsilateral white matter in frontal lobe) for CBF, CBV and MTT in the patient group were compared with those in the control group. RESULTS The CBF ratios for every ROI were higher in SHE patients versus the controls. Statistically, significant increases were detected in the left globus pallidus, putamen and thalamus (P<0.05) For MTT, the reduction in values reached statistical significance in the right head of the caudate nucleus and bilateral thalamus (P<0.05) CBV values were not significantly different compared with those of the control group (P>0.05) CONCLUSION Increased CBF and decreased MTT values in the basal ganglia and thalamus were identified in patients with SHE. The CBF increase was compatible with the idea that the CBF is redistributed from cortical areas to the basal ganglia structures.
author_names: Tao Li

Xin Li

Weihua Zhou

Xiaoming Cui

Lin Ma
title: Dynamic susceptibility contrast enhanced first pass perfusion MR imaging in patients with subclinical hepatic encephalopathy.
venue: Journal of neuroradiology. Journal de neuroradiologie
year: 2012

abstract: Abstract Purpose Despite their availability and simplicity of use, Electronic Portal Imaging Devices (EPIDs) have not yet replaced detector arrays for patient specific QA in 3D. The purpose of this study is to perform a large scale dosimetric evaluation of transit and non transit EPID dosimetry against absolute dose measurements in 3D. Methods After evaluating basic dosimetric characteristics of the EPID and two detector arrays (Octavius 1500 and Octavius 1000SRS) 3D dose distributions for 68 VMAT arcs, and 10 IMRT plans were reconstructed within the same phantom geometry using transit EPID dosimetry, non transit EPID dosimetry, and the Octavius 4D system. The reconstructed 3D dose distributions were directly compared by g analysis (2L2 2% local/2 mm and 3G2 3% global/2 mm, 50% isodose) and by the percentage difference in median dose to the high dose volume %HDVD 50) Results Regarding dose rate dependency, dose linearity, and field size dependence, the agreement between EPID dosimetry and the two detector arrays was found to be within 1.0% In the 2L2 g comparison with Octavius 4D dose distributions, the average g pass rate value was 92.2 5.2%(1SD) and 94.1 4.3%(1SD) for transit and non transit EPID dosimetry, respectively. 3G2 g pass rate values were higher than 95% in 150/156 cases. %HDVD 50 values were within 2% in 134/156 cases and within 3% in 155/156 cases. With regard to the clinical classification of alerts, 97.5% of the treatments were equally classified by EPID dosimetry and Octavius 4D. Conclusion Transit and non transit EPID dosimetry are equivalent in dosimetric terms to conventional detector arrays for patient specific QA. Non transit 3D EPID dosimetry can be readily used for pre treatment patient specific QA of IMRT and VMAT, eliminating the need of phantom positioning.
author_names: Igor Olaciregui-Ruiz

Begona Vivas-Maiques

Jochem Kaas

Thijs Perik

Frits Wittkamper

Ben J Mijnheer

Anton Mans
title: Transit and non transit 3D EPID dosimetry versus detector arrays for patient specific QA
venue: Journal of applied clinical medical physics
year: 2019

abstract: It has been recently claimed that KOIs 268.01, 303.01, 1888.01, 1925.01, 2728.01 3320.01 are exomoon candidates, based on an analysis of their transit timing. Here, we perform an independent investigation, which is framed in terms of three questions: 1) Are there significant excess TTVs? 2) Is there a significant periodic TTV? 3) Is there evidence for a non zero moon mass? We applied rigorous statistical methods to these questions alongside a re analysis of the Kepler photometry and find that none of the KOIs satisfy these three tests. Specifically, KOIs 268.01 3220.01 pass none of the tests and KOIs 303.01, 1888.01 1925.01 pass a single test each. Only KOI 2728.01 satisfies two, but fails the cross validation test for predictions. Further, detailed photodynamical modeling reveals that KOI 2728.01 favours a negative radius moon (as does KOI 268.01) We also note that we find a significant photoeccentric for KOI 1925.01 indicating an eccentric orbit of e>(0.62+ 0.06) For comparison, we applied the same tests to Kepler 1625b, which reveals that 1) and 3) are passed, but 2) cannot be checked with the cross validation method used here, due to the limited number of available epochs. In conclusion, we find no compelling evidence for exomoons amongst the six KOIs. Despite this, we're able to derive exomoon mass upper limits versus semi major axis, with KOI 3220.01 leading to particularly impressive constraints of Ms/Mp 0.4% [2 sigma] at a similar relative semi major to that of the Earth Moon.
author_names: David Kipping
title: An Independent Analysis of the Six Recently Claimed Exomoon Candidates
year: 2020

abstract: Objective:To evaluate computed tomography (CT) perfusion using first pass methods for lung nodule characterization. Methods:Fifty seven patients with 51 malignant and 6 benign nodules underwent first pass, dynamic contrast enhanced CT (50 mL, 3 5 mL/s. Kinetic analysis tools were CT Perfusion 3 (GEMS, Milwaukee, WI) a distributed parameter model approach, yielding blood volume (BV; mL/100 g) blood flow (BF; mL/min/100 g) mean transit time (1/s) and permeability surface area (mL/min/100 g) and an in house Patlak style analysis yielding fractional BV (mL/100 g) and an estimate of extraction (Kps, mL/100 g/min) Results:CT Perfusion 3 parameters in malignant and benign nodules were: mean transit time 10.1 0.9 1/s versus 11.1 3.1 1/s (ns) permeability surface 23.3 9.1 mL/min/100 g versus 19.6 10.3 mL/min/100 g (ns) BF 111.3 8.7 mL/min/100 g versus 39.1+ 5.7 mL/min/100 g (P 0.001) BV 9.3+ 0.7 mL/100 g versus 4.1 1.1 mL/100 g (P 0.002) Patlak parameters were: Kps 13.3 1.2 mL/100 g/min versus 3.9 0.8 mL/100 g/min (P 0.001) BV 8.4 0.8 mL/100 g versus 3.6 1.3 mL/100 g (P 0.01) The two kinetic methods show good agreement for BV estimation (Bland Altman plot) The limits of agreement (bias 2 standard deviation of bias) were 1.2 5.3 mL/100 g. Conclusion:CT Perfusion using first pass modeling appears feasible for lung nodule characterization. Given the short acquisition duration used, weaknesses of the modeling methods are exposed. Nonetheless, microvascular characterization in terms of BF, BV, or Kps appears useful in distinguishing malignant from benign nodules.
author_names: Igor Sitartchouk

Heidi C Roberts

Andre Pereira

Hamid Bayanati

Tom Waddell

Timothy P L Roberts
title: Computed Tomography Perfusion Using First Pass Methods for Lung Nodule Characterization
venue: Investigative radiology
year: 2008

abstract: OBJECTIVE To differentiate adrenal adenoma from metastasis in patients using perfusion computed tomography (PCT) imaging. METHODS Thirty two patients with adrenal masses underwent first pass PCT imaging. Of these patients, twenty one were diagnosed with adrenal adenoma, and the others with metastases. Perfusion maps of blood volume (BV) blood flow (BF) mean transit time (MTT) and permeability surface area production (PS) were generated with an Advantage Windows workstation using the CT perfusion 3.0 software (General Electric Medical Systems, Milwaukee, WI) Histopathologic sections immunostained for CD34 were quantitatively evaluated for microvessel density (MVD) RESULTS The perfusion parameters such as BV, BF and PS were statistically significant different between the two groups, with adenomas showing higher mean BV (12.18 versus 3.86) BF (97.51 versus 45.99) and PS (21.73 versus 10.93) compared with metastases (p<0.05) For BV, a cutoff point of 7.30 was found to have a sensitivity of 95.2% and a specificity of 100% to differentiate between adenoma and metastasis. The sensitivity and specificity were 81.0 and 80.0% respectively, for BF with a cutoff point of 71.96; and 85.7 and 86.7% respectively, for PS with a cutoff point of 12.70 to differentiate adenoma and metastasis. A comparison of MVD counts from adenomas with those from metastases showed a significant difference (p<0.05) However, no significant differences were observed in the four perfusion parameters and MVD between lipid rich and lipid poor adenomas. CONCLUSION PCT may be useful for evaluating the neovascularization of adrenal masses and differentiating adenoma from metastasis on the basis of PCT parameters. Adenomas show higher BV, BF and PS compared with metastases. According our data, the optimal threshold BV is 7.30, resulting in a sensitivity of 95.2% and a specificity of 100% for the differentiation of adenoma from metastasis. Adrenal adenomas have similar hemodynamic profiles, which are apparently independent of the lipid content of an adenoma.
author_names: Zhong-wei Qiao

Chunchao Xia

Yan-bo Zhu

Wei-ping Shi

Fei Miao
title: First pass perfusion computed tomography: initial experience in differentiating adrenal adenoma from metastasis.
venue: European journal of radiology
year: 2010

abstract: BackgroundDue to the different properties of the contrast agents, the lung perfusion maps as measured by 99mTc labeled macroaggregated albumin perfusion scintigraphy (PS) are not uncommonly discrepant from those measured by dynamic contrast enhanced MRI (DCE MRI) using indicator dilution analysis in complex pulmonary circulation. Since PS offers the pre capillary perfusion of the first pass transit, we hypothesized that an inflow weighted perfusion model of DCE MRI could simulate the result by PS.Methods22 patients underwent DCE MRI at 1.5T and also PS. Relative perfusion contributed by the left lung was calculated by PS (PSL% by DCE MRI using conventional indicator dilution theory for pulmonary blood volume (PBVL% and pulmonary blood flow (PBFL% and using our proposed inflow weighted pulmonary blood volume (PBViwL% For PBViwL% the optimal upper bound of the inflow weighted integration range was determined by correlation coefficient analysis.ResultsThe time to peak of the normal lung parenchyma was the optimal upper bound in the inflow weighted perfusion model. Using PSL% as a reference, PBVL% showed error of 49.24% to 40.37% (intraclass correlation coefficient RI 0.55) and PBFL% had error of 34.87% to 27.76% (RI 0.80) With the inflow weighted model, PBViwL% had much less error of 12.28% to 11.20% (RI 0.98) from PSL%.ConclusionsThe inflow weighted DCE MRI provides relative perfusion maps similar to that by PS. The discrepancy between conventional indicator dilution and inflow weighted analysis represents a mixed flow component in which pathological flow such as shunting or collaterals might have participated.
author_names: Yi-Ru Lin

Shang-Yueh Tsai

Teng-Yi Huang

Hsiao-Wen Chung

Yi-Luan Huang

Fu-Zong Wu

Chu-Chuan Lin

N J Peng

Ming-Ting Wu
title: Inflow weighted pulmonary perfusion: comparison between dynamic contrast enhanced MRI versus perfusion scintigraphy in complex pulmonary circulation
venue: Journal of Cardiovascular Magnetic Resonance
year: 2013

abstract: ABSTRACT Bees often forage in habitats with cluttered vegetation and unpredictable winds. Navigating obstacles in wind presents a challenge that may be exacerbated by wind induced motions of vegetation. Although wind blown vegetation is common in natural habitats, we know little about how the strategies of bees for flying through clutter are affected by obstacle motion and wind. We filmed honeybees Apis mellifera flying through obstacles in a flight tunnel with still air, headwinds or tailwinds. We tested how their ground speeds and centering behavior (trajectory relative to the midline between obstacles) changed when obstacles were moving versus stationary, and how their approach strategies affected flight outcome (successful transit versus collision) We found that obstacle motion affects ground speed: bees flew slower when approaching moving versus stationary obstacles in still air but tended to fly faster when approaching moving obstacles in headwinds or tailwinds. Bees in still air reduced their chances of colliding with obstacles (whether moving or stationary) by reducing ground speed, whereas flight outcomes in wind were not associated with ground speed, but rather with improvement in centering behavior during the approach. We hypothesize that in challenging flight situations (e.g. navigating moving obstacles in wind) bees may speed up to reduce the number of wing collisions that occur if they pass too close to an obstacle. Our results show that wind and obstacle motion can interact to affect flight strategies in unexpected ways, suggesting that wind blown vegetation may have important effects on foraging behaviors and flight performance of bees in natural habitats. Summary: To approach moving obstacles, honeybees reduce speeds in still air but increase speeds in wind. To transit obstacles, bees reduce speeds in still air but alter flight paths in wind.
author_names: Nicholas P Burnett

Marc A Badger

Stacey A Combes
title: Wind and obstacle motion affect honeybee flight strategies in cluttered environments
venue: Journal of Experimental Biology
year: 2020