Narrow Width Effect Research Articles

On-Chip Modification of Titanium Electrothermal Characteristics by Joule Heating: Application to Terahertz Microbolometer.

This study demonstrates the conversion of metallic titanium (Ti) to titanium oxide just by conducting electrical current through Ti thin film in vacuum and increasing the temperature by Joule heating. This led to the improvement of electrical and thermal properties of a microbolometer. A microbolometer with an integrated Ti thermistor and heater width of 2.7 µm and a length of 50 µm was fabricated for the current study. Constant-voltage stresses were applied to the thermistor wire to observe the effect of the Joule heating on its properties. Thermistor resistance ~14 times the initial resistance was observed owing to the heating. A negative large temperature coefficient of resistance (TCR) of -0.32%/K was also observed owing to the treatment, leading to an improved responsivity of ~4.5 times from devices with untreated Ti thermistors. However, this does not improve the noise equivalent power (NEP), due to the increased flicker noise. Microstructural analyses with transmission electron microscopy (TEM), transmission electron diffraction (TED) and energy dispersive X-ray (EDX) confirm the formation of a titanium oxide (TiOx) semiconducting phase on the Ti phase (~85% purity) deposited initially, further to the heating. Formation of TiOx during annealing could minimize the narrow width effect, which we reported previously in thin metal wires, leading to enhancement of responsivity.

Narrow-Width Effects in 28-nm FD-SOI Transistors Operating at Cryogenic Temperatures

In this paper, we present on the cryogenic characterization of short channel 28-nm FD-SOI nMOS and pMOS transistors having widths of the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1 ~\mu \text{m}$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.08 ~\mu \text{m}$ </tex-math></inline-formula> at temperatures ranging from T = 300 K down to T = 10 K. We report, for the first time, the alarming concerns that the narrow-width effect imposes on the overall performance of highly scaled FD-SOI technologies, at temperatures below T = 77 K. The performance comparison between nMOS and pMOS devices is based on their drain current, threshold voltage, transconductance, subthreshold slope, low field mobility and total resistance. Our results show that the sensitivity of narrow width effects towards drain current, threshold voltage and total resistance is smaller in pMOS as compared to nMOS. The effective improvement in transconductance is also significantly larger in narrow width pMOS in comparison to their nMOS counterparts. A substantial degradation of subthreshold swing, total resistance and low field mobility is also observed in narrow nMOS devices, which questions the width scaling benefits of these technologies at cryogenic temperatures.

Modeling and Characterization of the Narrow-Width Effect of 4H-SiC MOSFETs With Local Oxidation of SiC Isolation

In this article, the narrow-width effect (NWE) of 4H-SiC MOSFETs with local oxidation of SiC (LOCOSiC) isolation is reported. A channel width-dependent current hump was observed in the subthreshold region for n-type 4H-SiC MOSFETs with LOCOSiC, and a channel width-dependent threshold voltage ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${V} _{th}$ </tex-math></inline-formula> ) shift was observed for p-type 4H-SiC MOSFETs with LOCOSiC. This unusual NWE arises from the increase in the gate oxide thickness from the channel center toward the isolation edge and is different from the conventional NWE found in local oxidation of silicon (LOCOS) technology, which arises from the charge stored in the parasitic field oxide (FOX) capacitor and lateral dopant encroachment. A H2O diffusion and oxidation model is proposed in this article to explain the growth of a long bird’s beak in 4H-SiC MOSFETs with LOCOSiC. Technology computer-aided design (TCAD) simulations were executed to explore the H2O diffusion behavior of these MOSFETs, and an analytical formula was derived to predict the oxide layer thickness and length of bird’s beak along the diffusion path in the H2O diffusion and oxidation model. The problems caused by the long bird’s beak and unusual NWE can be overcome by increasing the overetching time of the pad oxide removal and marginally decreasing the thickness of the FOX layer. Therefore, the NWE of the LOCOSiC isolation is expected to be weaker than that of the LOCOS isolation because field implantation is unnecessary, and thus, dopant encroachment does not occur in the LOCOSiC technology.

Mobility Enhancement and Abnormal Humps in Top-Gate Self-Aligned Double-Layer Amorphous InGaZnO TFTs

The mobility enhancement and the positive bias stress of top-gate self-aligned TFTs using the a-IGZO channel with a front barrier are investigated. The a-IGZO front barrier can keep electrons in the a-IGZO channel away from the top-gate oxide to significantly enhance the electron mobility at the top gate operation. The parasitic channel induces a hump in the transfer characteristics. The positive bias stress shifts the hump to the negative voltage abnormally. The H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O in the polymer film on array layer is responsible for the abnormal shift. The H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O diffuses into the top-gate insulator and is electrolyzed to create H <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> , which forms a parasitic channel with a negative shift of threshold voltage, leading to the abnormal hump. The abnormal humps are increasingly significant with the increasing channel width and the decreasing channel length. The channel width dependence on positive bias stress is due to the inverse narrow width effect caused by the fringe electric field. The channel length dependence on positive bias stress is due to the H <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> diffusion toward the center of the parasitic channel from both the source and drain sides.

A Biomechanical Analysis of Wide, Medium, and Narrow Grip Width Effects on Kinematics, Horizontal Kinetics, and Muscle Activity on the Sticking Region in Recreationally Trained Males During 1-RM Bench Pressing.

Grip width has been found to affect lifting performance, especially around the sticking region; however, little is known about the kinetics and muscle activities that could explain these differences in performance. This study aimed to investigate the effects of grip width on the joint, barbell kinematics, and horizontal kinetics, analyzed in tandem with the effects of muscle activation around the sticking region in the one repetition maximum (1-RM) barbell bench press. Fourteen healthy bench press-trained males (body mass: 87.8 ± 18.4, age: 25 ± 5.4) performed 1-RM with a small, medium, and wide grip width. The participants bench pressed 109.8 ± 24.5 kg, 108.9 ± 26.4 kg, and 103.7 ± 24 kg with the wide, medium, and narrow grip widths. Furthermore, the wide grip width produced 13.1–15.7% lateral forces, while the medium and narrow grip widths produced 0.4–1.8 and 8.5–10.1% medially directed forces of the vertical force produced during the sticking region, respectively. Horizontal forces did not increase during the sticking region, and the resultant forces decreased during the sticking region for all grip widths. The wide and medium grip widths produced greater horizontal shoulder moments than the narrow grip width during the sticking region. Hence, the wide and medium grip widths produced similar shoulder and elbow joint moments and moment arm at the first located lowest barbell velocity. Furthermore, triceps medialis muscle activity was greater for the medium and narrow grip widths than the wide grip width. This study suggests that the sticking region for the wide and medium grip widths may be specific to the horizontal elbow and shoulder joint moments created during this region. Therefore, when the goal is to lift as much as possible during 1-RM bench press attempts among recreationally trained males, our findings suggest that bench pressing with a wide or medium grip width may be beneficial.

Geometric Modeling of Thermal Resistance in GaN HEMTs on Silicon

In this article, pulsed measurements of thermal resistance in GaN-based high-electron mobility transistors (HEMTs) on silicon, with different gate geometries and gate-to-drain extensions, are analyzed and modeled. Simple expressions for the thermal resistance of silicon-on-insulator (SOI) MOSFETs, which take into account the gate width and channel length, can be adapted to model the thermal resistance of these GaN-based HEMTs. Narrow width effects and the increase in the heat flow through the gate as the channel length increases were correctly reproduced. In addition, numerical simulations were performed to explain the reduction obtained in thermal resistance as the gate-to-drain extension increases. Our approach can also be applied easily to other well-established models using circuit simulators.

65 nm sub‐threshold logic standard cell library using quasi‐Schmitt‐trigger design scheme and inverse narrow width effect aware sizing

In this study, the authors propose a sub-threshold standard cell library in which the quintessence is a quasi-Schmitt-trigger logic design scheme and the inverse narrow width effect aware sizing method. The techniques can improve the I on-to-I off ratio of the logic cells effectively and provide a significant suppression in leakage current, enhancing the robustness of the circuits. Simulation results show that the NAND3 and NOR3 logics with the new techniques achieve 40–60% and 30–50% reductions in leakage power compared with conventional logic circuits, respectively, when the voltage is scaled down to sub-threshold region. Again, they also exhibit considerable improvements in process variation immunity and power-delay product.

An optimal device sizing for a performance-driven and area-efficient subthreshold cell library for IoT applications

Ultra-low power design techniques specifically subthreshold designs, play a vital role in Internet of things systems that survive on limited power budget or harvested energy sources. In this paper, the width and length of a transistor operating at subthreshold region are optimized considering the nano-scale effects such as reverse short channel effect and inverse narrow width effect, which improves performance, reduces area, minimizes sensitivity to process variation and reduces energy consumption. A subthreshold standard cell library consisting of 45 standard cells is designed. The physical synthesis of ISCAS′85 benchmark circuits and a floating point unit shows that energy savings in area-mapped design are up to 23% whereas area savings in performance-mapped design are up to 30%. The measurement results from a test chip fabricated in industrial 130 nm technology demonstrate a performance improvement of up to 27%, reduction in delay variability of up to 24% and energy savings of 18%.

Six‐track multi‐finger standard cell library design for near‐threshold voltage operation in 130 nm complementary metal oxide semiconductor technology

In this study, a six-track standard cell library with a multi-finger layout structure is proposed to improve the delay, energy, and area of the digital circuit design for near-threshold operation. The proposed library is optimised by using the parasitic effects of the technology and optimising the layout. To enhance the performance and energy efficiency, inverse narrow width effect has been considered in the design, whereby the minimum width of the process was used as the based width unit. To minimise the design area, the standard cell was designed in the lowest possible height with a multi-finger layout structure. The proposed library with a few basic cells was developed and characterised in 130 nm technology, which is available for synthesis and automatic place-and-route (P&R). The proposed library was analysed and compared with two eight-track multiplier layout libraries in the cell and block design level. Based on the place-and-route results of ISCAS'85 benchmark circuits, the proposed six-track library could achieve up to 27% of delay improvement, 29% energy reduction and 44% area reduction as compared to the multiplier structure library at the minimum critical path delay.

An energy-efficient variation aware self-correcting latch

Power dissipation is a prime concern in sub-nanometer VLSI regime and, therefore, operation at near/sub-threshold regime has gained importance. However, though energy efficient, a system performance/functionality is at stake, because of the increase in the variability in near/sub-threshold regime. Therefore, resilient circuit approaches are important in alleviating the performance degradation resulting from Process, Voltage, and Temperature (PVT) variations. This paper presents an energy efficient and resilient circuit design approach using novel self correcting latches. The proposed technique corrects the faults due to timing violation caused by variations in datapaths and sequential elements automatically, thereby lowering PVT variation induced performance degradation. Our technique employs Inverse Narrow Width Effect (INWE) in designing the self-correcting latches to reduce performance variability. In this technique INWE is used to realize devices which have equal gate capacitances and different current drives. We validate the proposed methodology on several ISCAS′89 benchmark circuits and 74X series circuits. Simulation results show that by employing the proposed methodology, an average improvement of ∼20%, 10%, and 4.85% in delay, power delay product, and layout area, respectively, over previous resilient methodologies can be achieved.

A 0.12–0.4 V, Versatile 3-Transistor CMOS Voltage Reference for Ultra-Low Power Systems

In this paper, we propose an ultra-low power compact 3-transistor voltage reference capable of operating at ultra-low supply voltages. The proposed circuit is based on the self-cascode MOSFET (SCM), which provides a reference voltage proportional to the threshold voltage ( $V_{T}$ ) difference of the two NMOS transistors that compose it. Reverse short-channel and narrow-width effects are explored to obtain such $V_{T}$ difference while using the same type of transistor. Ultra-low power operation and low line sensitivity is achieved by biasing the SCM with a zero- $V_{T}$ (native) transistor, also leading to an area efficient design. To show its versatility, three versions of the proposed circuit were fabricated in a standard 0.13- $\mu \text{m}$ CMOS process. Measurement performed over five samples showed an average temperature coefficient of 150–1500 ppm/°C. Minimum supply voltages of 0.12–0.4 V was observed while providing reference voltages around tens of mV. The proposed circuits consume 0.33–50 pW at room temperature and minimum supply voltage. The occupied area for any version is less than 0.0012 mm2.

Effective Drive Current for Near-Threshold CMOS Circuits’ Performance Evaluation: Modeling to Circuit Design Techniques

This paper presents an effective current model ( ${I}_{\textsf {eff}}$ ) for a near-threshold voltage (NTV) inverter and two-input NAND/NOR gates. The proposed model is validated by 2-D technology computer-aided design mixed-mode device simulations and HSPICE simulations at two different technology nodes. When compared with our model, the existing nominal supply voltage ${I}_{\textsf {eff}}$ models fail to estimate an inverter/NAND/NOR gate performance in the NTV regime. The proposed model is also validated for process, voltage, and temperature variations. Performance variation due to layout-dependent effects (LDEs) and inverse narrow width effect (INWE) are significant in the NTV regime. Therefore, the model is validated while considering LDEs. We show that due to LDEs and INWE, the value of ${I}_{\textsf {eff}}$ per unit width is a function of the device width and the number of fingers. To account for this effect, a systematic methodology is presented to optimize a circuit performance in the NTV domain. An inverter chain with ${C}_{\textsf {out}}/{C}_{\textsf {in}}=\textsf {2000}$ designed employing our methodology results in 3.2%, 35%, and 30% improvement in the delay, energy per operation, and total transistor width, respectively, as compared with existing methodologies. Similarly, data paths resized using the proposed methodology result in a significant performance improvement when compared with their conventionally designed counterparts.

A Near-Threshold Voltage Oriented Digital Cell Library for High-Energy Efficiency and Optimized Performance in 65nm CMOS Process

A digital cell library operating in the near-threshold voltage (NTV) region is presented to obtain both high energy efficiency and optimized performance. The proposed library oriented to the NTV region is optimized using the parasitic effects of nanometer process technology and a body-biasing technique. To maximize the energy efficiency, the proposed cell library utilized the minimum width allowed by the process as the base width unit. To enhance the performance, digital cells were developed with various strengths whose sizing method relies on the minimum unit width, reverse short channel effect, and inverse narrow width effect. An asymmetric gate-length scheme is applied to multi-fan-in logic gates to increase the performance. Also, the proposed TAP cell was added, combined with an inverter-based forward body-biasing circuit. Finally, a library with 59 cells was developed and made available for synthesis and automatic layout and the proposed NTV library was then evaluated with ISCAS benchmark logics. The proposed NTV cell library shows more than 10~20% less energy consumption compared with a conventional digital cell library using minimum gate length and monolithic width. EDP is also increased by 10~20% with a simply controlled body-biasing scheme compared with the conventional one.

Adjustable Silicon Corner Rounding Radius by Wet Technique

Shallow trench isolation (STI) and active area (AA) top corner rounding is important to devices performance. AA top corner rounding techniques include STI etch, linear oxidation , H2 annealing and wet oxide pull back (PB). However, conventional STI etch will caused AA facet and need to additional thermal in linear oxidation or H2 annealing processes. Wet oxide PB is easily to control the pad oxide etching amount and reach desired AA top corner top rounding radius.In this study, different pad oxide PB amount by Hydrogen Fluoride (HF) with corner rounding correlation were shown. At high pad oxide PB amount, additional hydrogen peroxide (H2O2) with dilute HF can optimize the AA top corner profile and enlarge the corner radius. Sharp AA corners profile caused gate oxide formation thickness thinning let strong electrical filed at AA corner. In wafer acceptable test had brought about double hump effect in I-V characteristics and inverse narrow width effect. Pad oxide PB following STI Etch is used by HF to let the silicon top corner be exposed and beneficial for increasing AA top corner rounding radius of liner oxidation process. This study gives some course to improve the silicon corner profile and AA top corner radius. After STI etch process, different wet etch amount were used for pad oxide PB from pad nitride by 0.49% HF process time adjustment. Different wet oxide PB amount were split for corner radius comparison. As oxide PB amount increased from 0nm to 5nm the corner radius can be improved, and the best radius showed at PB 5nm. When oxide PB amount add to 7.5nm, the corner radius became worse slightly. The radius of PB 10nm is even worse and close to without oxide PB process. This result suspected that AA corner profile might be changed in wet oxide PB process. When oxide PB amount increase, oxide etch rate might decrease and exposed silicon corner be continually damaged by HF erosion. The silicon damage of PB 5nm is slight and can be recovered after linear oxidation thermal process. At PB 7.5nm the AA corner “stepped” profile was observed. It can explain while the PB amount >5nm the corner rounding radius decrease. Because the “stepped” profile caused the corner split two curvatures then the radius decrease. The “stepped” profile of PB amount >7.5nm still be find after linear oxidation. To reduce the AA top corner “stepped” profile, the post-HF treatment’s AA silicon exposed in following APM process. The AA top corner and silicon sidewall which with APM treatment is clipping suspect H2O2 oxidize silicon and NH4OH consume the oxide caused. This profile made the region of exposed silicon to be deficient and pointed in AA geometry of silicon corner. The pointed AA top corner profile is unhelpful for corner rounding radius improvement, so the key factor of AA top rounding profile is corner silicon loss controller. In order to reduce the corner silicon loss amount, using H2O2 to replace the APM and dilute HF concentration to do oxide PB. This optimistic experience will be expected lower the exposed corner silicon consumption and corner rounding radius improvement. According oxide PB amount 5nm and 7.5nm comparison in 0.49%HF, the corner radius reduced 0.1nm when the PB increased. Nonetheless, HF concentration changed from 0.49% to 0.1% and H2O2 addition, the corner radius can be improved 0.3nm and 0.7nm. This result proved that the corner silicon profile of PB >5nm will be damaged in concentrated HF wet etch. Change to dilute HF concentration will reduce corner silicon loss and enable to recover corner silicon which with “stepped” profile by additional H2O2 treatment. As the higher oxide PB amount the pad oxide PB rate will become lower cause that without oxide protected corner silicon will be damaged and result in “stepped” profile. Nevertheless, using dilute HF can lower corner silicon loss and reduce the silicon erosion which without oxide protected. Additional H2O2 treatment introduced the rounding and smooth profile. The relationship between pad oxide PB and AA top corner rounding is established in STI process. The AA top corner radius of oxide PB amount 5nm can be improved 2.6nm compare to without PB process. When oxide PB amount >5nm the corner radius is decreased. The decreasing corner radius come from higher oxide PB amount that without oxide protected corner silicon will be damaged. This phenomenon result in “stepped” profile with difference curvature and corner radius decreasing. Dilute HF with H2O2 treatment is demonstrated that it is beneficial to reduce and recover the corner damaged. Figure 1

Optimization of narrow width effect on titanium thermistor in uncooled antenna-coupled terahertz microbolometer

Uncooled antenna-coupled terahertz microbolometer arrays are fabricated with a meander-type Ti thermistor, and design widths (DW) = 0.1 and 0.2 µm, considering the design requirement to miniaturize detectors. Each unit device with DW = 0.1 µm of the thermistor has about 4.7 time higher electrical responsivity (132 V/W) than that with DW = 0.2 µm (28.2 V/W) at 10 µA bias current. For DW = 0.2 µm, the calculated noise equivalent power (NEP) was 2.29 × 10−9 W/, whereas the minimum NEP of 4.43 × 10−10 W/ was obtained for DW = 0.1 µm devices, both at 10 µA bias current. The bulk value of temperature coefficient of resistance (TCR) of the Ti thermistor is markedly compromised in low dimensional devices, still in terms of responsivity and NEP, unit devices with Ti thermistor with the lower DW shows better performance. This is because the narrow width effect is minimized owing to higher resistivity for DW = 0.1 than that for DW = 0.2 µm. In this current report, we highlights the optimization of the narrow width effect on TCR of metal interconnects in nanometer dimensions, which to the best of our knowledge is not available at present.

Characterization of platinum and titanium thermistors for terahertz antenna-coupled bolometer applications

Microbolometer is a radiation detector for infrared (IR) and terahertz (THz) waves. The temperature coefficient of resistance (TCR) of the thermistor is a vital factor, as the responsivity is proportional and noise equivalent power (NEP) is inversely proportional to it. The narrow-width effect on TCR and resistivity on two different substrates (SiO2/Si and SiNX/SiO2/Si) for platinum (Pt) and titanium (Ti) thermistor with various design width (DW) = 0.1–5 μm are investigated. Increased resistivity and reduced TCR of the devices with the decreased line width, is observed commonly for both metal and fitted with empirical formulae, which hold well for different substrates. It is evident from electron backscatter diffraction (EBSD) results showing reduced average grain size form Ti film to Ti nanowire (DW = 0.1 μm), that the reduced TCR is not dependent on crystal orientation or phase variation of material but can be correlated with reduced grain size due to reduction of width. The optimum value considering design requirement, thermistor of DW = 0.1 μm and 0.2 μm is used further for the fabrication of microbolometers. It is found that the device with DW = 0.1 μm of Ti thermistor has ∼1.5 times higher electrical responsivity (376 V/W) at maximum allowable current than that with DW = 0.2 μm (254 V/W), which is also ∼11 times higher than device with DW = 0.1 μm of Pt thermistor.

Width dependence of platinum and titanium thermistor characteristics for application in room-temperature antenna-coupled terahertz microbolometer

For application in a room-temperature microbolometer to detect terahertz waves, “narrow-width effects” on the temperature coefficient of resistance (TCR) and resistivity (ρ) for platinum (Pt) and titanium (Ti) nanowires are investigated. The TCR and ρ of a thermistor could be described by empirical formulas with average measured widths for higher precision. The effect of width on TCR in Pt is lower than that in Ti. The noise equivalent power of the microbolometer could be improved by a factor of 2.3 by replacing the Ti thermistor with a Pt thermistor of the same width (100 nm). The results provide a detailed understanding of the narrow-width effect on TCR for Pt and Ti, which, to our knowledge, is lacking at present.

A Framework to Simulate Semiconductor Devices Using Parallel Computer Architecture

Device simulations have become an integral part of semiconductor technology to address many issues (short channel effects, narrow width effects, hot-electron effect) as it goes into nano regime, helping us to continue further with the Moore's Law. TCAD provides a simulation environment to design and develop novel devices, thus a leap forward to study their electrical behaviour in advance. In this paper, a parallel 2D simulator for semiconductor devices using Discontinuous Galerkin Finite Element Method (DG-FEM) is presented. Discontinuous Galerkin (DG) method is used to discretize essential device equations and later these equations are analyzed by using a suitable methodology to find the solution. DG method is characterized to provide more accurate solution as it efficiently conserve the flux and easily handles complex geometries. OpenMP is used to parallelize solution of device equations on manycore processors and a speed of 1.4x is achieved during assembly process of discretization. This study is important for more accurate analysis of novel devices (such as FinFET, GAAFET etc.) on a parallel computing platform and will help us to develop a parallel device simulator which will be able to address this issue efficiently. A case study of PN junction diode is presented to show the effectiveness of proposed approach.

Effect of Pregate Carbon Implant on Narrow Width Behavior and Performance of High- Metal-Gate nMOS Transistors

This paper experimentally shows the reduction of anomalous narrow width effect (NWE) observed in gate-first high- $k$ metal-gate (HKMG) nMOS transistors by using pregate carbon implants. The experiments are performed with different carbon implant doses and energies, in collaboration with a semiconductor foundry. The 28-nm gate-first HKMG CMOS technology is used as the baseline flow. The physical mechanisms responsible for this improvement are identified and explained in detail. It is further shown that the pregate carbon implant used to suppress the NWE also increases junction leakage, improves the device electrostatics, and improves the universal curve.

Multifinger MOSFETs’ Optimization Considering Stress and INWE in Static CMOS Circuits

Strain engineering and inverse narrow width effect (INWE) are among the main causes of layout-dependent variations in narrow width devices. Transistor sizing and layout without considering these effects at a prelayout stage may result in suboptimal design and design/layout iterations. In this paper, we model the channel stress variations in multifinger gate structure (MFGS) empirically using 3-D technology computer aided design simulations. Thereafter, we use these stress models along with a model for INWE to establish a physics-based relationship between effective drive current and number of fingers in MFGS. We also design single-stage combinational standard cells and predict the values of their logical effort using our approach. The performance of the standard cells using our approach improves significantly compared with the conventional approach. Inverter chains (buffers) are representative and extensively used multistage circuits. Using our model of effective drive current, we propose a methodology to optimize the buffer designed and layout to maximize performance in stress-enabled technologies. We observe that the proposed methodology results in a significant reduction in power dissipation up to 35% and reduction in silicon area up to 43% as compared with the existing methodologies.