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An explicit model is proposed for lightly doped FinFETs, which is valid and continuous in all operating regimes for channel lengths down to 25 nm, Fin widths down to 3 nm and Fin heights down to 50 nm with a single set of parameters. Short-channel effects, subthreshold slope degradation, drain-induced barrier lowering, drain saturation voltage with saturation, channel length modulation and quantum mechanical effects are taken into consideration by these studies.

This paper proposes an approach for the accurate and efficient parameter identification of lithium-ion battery packs using only drive cycle data obtained from hybrid or electric vehicles. The approach was experimentally validated using data collected from a BMW i8 hybrid vehicle. The dual polarization model was used, and a new open circuit voltage equation was proposed based on a simplification of the combined model, with the aim of reducing the number of parameters to be identified. The parameter identification was performed using NEDC data collected on a rolling road dynamometer; the results showed that the proposed model improved the accuracy of terminal voltage estimation, reducing the peak voltage error from 2.16% using the Nernst model to 1.28%. Furthermore, the robustness of these models in maintaining accuracy when new drive cycles were used was evaluated by comparing WLTC simulations with experimental measurements. The proposed model showed improved robustness, with a reduction in RMS error of more than 50% compared to the Nernst model. These findings are significant because they will improve the accuracy of model-based battery management systems used in electric vehicles, allowing for improved performance prediction without the requirement of recharacterization for different drive cycles or individual cell characterization. [ABSTRACT FROM AUTHOR]

This paper examines aspects of design technology required to explore advanced logic-circuit design using carbon nanotube field-effect transistor (CNTFET) devices. An overview of current types of CNTFETs is given and highlights the salient characteristics of each. Compact modeling issues are addressed and new models are proposed implementing: 1) a physics-based calculation of energy conduction sub-band minima to allow a realistic analysis of the impact of CNT helicity and radius on the dc characteristics; 2) descriptions of ambipolar behavior in Schottky-barrier CNTFETs and ambivalence in double-gate CNTFETs (DG-CNTFETs). Using the available models, the influence of the parameters on the device characteristics were simulated and analyzed. The exploitation of properties specific to CNTFETs to build functions inaccessible to MOSFETs is also described, particularly with respect to the use of DG-CNTFETs in fine-grain reconfigurable logic. Index Terms--Circuit simulation, carbon nanotube field-effect transistor (CNTFET), compact model, reconfigurable logic gates.

A simple, physics-based and continuous model for the quantum effects and polydepletion in deep-submicrometer MOSFETs with very thin gate oxide thickness is presented. The model offers simple relationships among effective electrical parameters and physical device parameters, providing insight into the physical phenomena.

An analytical one-dimensional thermoelectrical model for the power MOSFET transistor (VDMOS transistor) has been developed and implemented in the Saber circuit simulator. The device temperature becomes an interactive variable during the simulation. The model results in the combination of the electrical model of the device with a thermal network which models the different material layers crossed by the heat flow from the silicon chip to the heatsink (conduction phenomenon), and also takes into account the radiation and convection phenomena. The accuracy of the model is evaluated with electrical and thermal characterizations, and with a validation circuit. Index Terms - Characterization, CAD, modeling, power MOSFET transistor, thermal behavior, thermal dissipation, thermo-electrical interactions.

Gene regulatory networks exhibiting Boolean behaviour, e.g. AND, OR or XOR, have been routinely designed for years. However, achieving more sophisticated functions, such as control or computation, usually requires sequential circuits or so-called state machines. For such a circuit, outputs depend both on inputs and the current state of the system. Although it is still possible to design such circuits by analogy with digital electronics, some particularities of biology make the task trickier. The impact of two of them, namely the stochasticity of biological processes and the inhomogeneity in the response of regulation mechanisms, are assessed in this paper. Numerical simulations performed in two use cases point out high risks of malfunctions even for designed GRNs functional from a theoretical point of view. Several solutions to improve reliability of such systems are also discussed. [ABSTRACT FROM AUTHOR]

The design of biosystems, biosensors, and lab-on-chips is an important field of investigation since the beginning of this century. The miniaturization and the integration constraints make the design of such systems challenging, and it is no longer possible to uncouple biology (or biochemistry) from the rest of the system. The interest of extending microelectronics computer-aided design tools to multidomain systems has already been demonstrated for two decades. Today, it becomes necessary to include biology among these domains. To enable such an evolution, we demonstrate an analogy between the behavior of biochemical systems and electrical circuits. This analogy is exploited to develop a tool for the description and the simulation of biological systems with SPICE. In addition, another analogy is drawn between molecular diffusion and heat diffusion. We also rely on it to develop an innovative framework for the simulation with SPICE of reaction–diffusion problems. The interest of such an approach is illustrated in the design of a penicillin sensor. A complete model of the system, which integrates biochemistry, electrochemistry, and electronics, is obtained. This model is then simulated for a first dimensioning of the sensor. [ABSTRACT FROM AUTHOR]

The state-of-the-art RF and millimeter-wave circuits design requires accurate prediction of the nonquasi-static (NQS) effects at high frequency for all levels of channel inversion. This paper provides a practical insight to help high-frequency performance assessment of ultrathin body and box fully depleted silicon-on-insulator MOSFETs through a powerful frequency normalization scheme. Frequency dependence of small signal characteristics derived from experimental S-parameters is analyzed and reveals that the transconductance efficiency (${g}_{\textsf {m}}/{I}_{\textsf {D}}$) concept, already adopted as a low-frequency analog figure-of-merit (FoM), can be generalized to high frequency, including under asymmetric operation. We report that the normalized frequency dependence of the generalized transadmittance efficiency (${y}_{\textsf {m}}/{I}_{\textsf {D}}$) FoM only depends on the mobility and inversion coefficient. In addition, this approach is also used to extract essential parameters such as the critical NQS frequency ${f}_{\textsf {NQS}}$. [ABSTRACT FROM AUTHOR]

Transconductance efficiency ( gm/{I}D ) is an essential design synthesis tool for low-power analog and RF applications. In this paper, the invariance of gm/{I}D versus normalized drain current curve is analyzed in an asymmetric double-gate (DG) fully depleted MOSFET. This paper studies the breakdown of this invariance versus back-gate voltage, transistor length, temperature, drain-to-source voltage, and process variations. The unforeseeable invariance is emphasized by measurements of a commercial 28-nm ultrathin body and box fully depleted Silicon-on-Insulator (SOI) (FDSOI) CMOS technology, thus supporting the gm/{I}D -based design methodologies usage in DG FDSOI transistors sizing. [ABSTRACT FROM AUTHOR]

The article deals with BB-SPICE (SPICE for Biochemical and Biological Systems), an extension of the famous Simulation Program with Integrated Circuit Emphasis (SPICE). BB-SPICE environment is composed of three modules: a new textual and compact description formalism for biological systems, a converter that handles this description and generates the SPICE netlist of the equivalent electronic circuit and NGSPICE which is an open-source SPICE simulator. In addition, the environment provides back and forth interfaces with SBML (System Biology Markup Language), a very common description language used in systems biology. BB-SPICE has been developed in order to bridge the gap between the simulation of biological systems on the one hand and electronics circuits on the other hand. Thus, it is suitable for applications at the interface between both domains, such as development of design tools for synthetic biology and for the virtual prototyping of biosensors and lab-on-chip. Simulation results obtained with BB-SPICE and COPASI (an open-source software used for the simulation of biochemical systems) have been compared on a benchmark of models commonly used in systems biology. Results are in accordance from a quantitative viewpoint but BB-SPICE outclasses COPASI by 1 to 3 orders of magnitude regarding the computation time. Moreover, as our software is based on NGSPICE, it could take profit of incoming updates such as the GPU implementation, of the coupling with powerful analysis and verification tools or of the integration in design automation tools (synthetic biology). [ABSTRACT FROM AUTHOR]

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Copyright of J3eA is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, synthetic biology is a hot research topic. Each day, progresses are made to improve the complexity of artificial biological functions in order to tend to complex biodevices and biosystems. Up to now, these systems are handmade by bioengineers, which require strong technical skills and leads to nonreusable development. Besides, scientific fields that share the same design approach, such as microelectronics, have already overcome several issues and designers succeed in building extremely complex systems with many evolved functions. On the other hand, in systems engineering and more specifically in microelectronics, the development of the domain has been promoted by both the improvement of technological processes and electronic design automation tools. The work presented in this paper paves the way for the adaptation of microelectronics design tools to synthetic biology. Considering the similarities and differences between the synthetic biology and microelectronics, the milestones of this adaptation are described. The first one concerns the modeling of biological mechanisms. To do so, a new formalism is proposed, based on an extension of the generalized Kirchhoff laws to biology. This way, a description of all biological mechanisms can be made with languages widely used in microelectronics. Our approach is therefore successfully validated on specific examples drawn from the literature. [ABSTRACT FROM PUBLISHER]

In this paper, we evidence the link between the planar and cylindrical junctionless field effect transistors (JL-FETs) from the electrostatics and current point of view. In particular, we show that an approximate solution of the Poisson–Boltzmann equation for JL nanowires can be mapped on the planar double-gate topology generating only negligible mismatch, meaning that both devices can share the same core model as far as long channels are considered. These preliminary results are a first step toward a unification of compact models for JL-FETs. [ABSTRACT FROM PUBLISHER]

In this letter, we propose to introduce the notion of equivalent capacitance and to generalize the so-called equivalent-thickness concept to model arbitrary shapes of lightly doped nonplanar multigate MOSFETs, without the need to introduce any unphysical parameter. These definitions, which merely map a multigate geometry into the symmetric double-gate (DG) MOSFET topology, have been validated by extensive comparison with 3-D numerical simulations of quadruple-gate, triple-gate (TG), triangular gate, cylindrical gate-all-around, and DG Fin Field Effect Transistors (FinFETs). Based on this modeling approach, any multigate architecture inherits of the fundamental relationships that have been developed for planar DG MOSFETs, including the normalization of all electrical quantities that considerably simplifies its analysis. In addition, considering a constant mobility, we find that the model can predict electrical characteristics of FinFETs from 275 to 425 K, without the need for any additional parameters. Finally, we were able to predict electrical measurements of a TG MOSFET, making of this generic model an interesting candidate for a design-oriented compact model for arbitrary multigate MOSFETs geometries. [ABSTRACT FROM PUBLISHER]

We derived an analytical model for the junctionless double-gate metal–oxide–semiconductor field-effect transistor (DG MOSFET) device, the principle of which has been recently demonstrated. Despite some similarities with classical junction-based DG MOSFETs, the charge–potential relationships are quite different and cannot be merely mapped on existing multigate formalisms. This is particularly true for the technological parameters of interest where reported doping densities exceed \10^19 \ \cm^-3 for 10- and 20-nm silicon channel thicknesses. Assessment of the model with numerical simulations confirms its validity for all regions of operation, i.e., from deep depletion to accumulation and from linear to saturation. [ABSTRACT FROM PUBLISHER]

In this paper, we propose to derive an analytical model for the doped symmetric double-gate (DG) MOSFET that is valid in all regions of operation. We show that doping the silicon channel can be converted in an equivalent silicon thickness and threshold voltage shift using a formalism developed for the undoped device. Adopting the same physical parameters, we demonstrate that this approach is in agreement with numerical technology computer-aided design simulations. This concept is therefore an interesting basis for a unified model for doped and undoped symmetric DG MOSFETs. [ABSTRACT FROM PUBLISHER]

An explicit charge-based compact model for lightly doped FinFETs is proposed. This design-oriented model is valid and continuous in all operating regimes (subthreshold, linear, and saturation) for channel lengths (L) down to 25 nm, Fin widths (Wsi) down to 3 nm, and Fin heights (Hsi) down to 50 nm with a single set of parameters. It takes short-channel effects, subthreshold slope degradation, drain-induced barrier lowering, drain saturation voltage with velocity saturation, channel length modulation, and quantum mechanical effects into account. [ABSTRACT FROM AUTHOR]

This paper presents a new compact model for the undoped, long-channel double-gate (DG) MOSFET under symmetrical operation. In particular, we propose a robust algorithm for computing the mobile charge density as an explicit function of the terminal voltages. It allows to greatly reduce the computation time without losing any accuracy. In order to validate the analytical model, we have also developed the 2D simulations of a DG MOSFET structure and performed both static and dynamic electrical simulations of the device. Comparisons with the 2D numerical simulations give evidence for the good behaviour and the accuracy of the model. Finally, we present the VHDL-AMS code of the DG MOSFET model and related simulation results. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

While the last decade has been dominated by Berkeley's BSIM3 and BSIM4 models (third generation models), a new type of compact models like HiSIM, SP, MM11 or EKV3 is more and more accepted in the semiconductor industry. These new models are either surface-potential-based models or charge linearization models (EKV3) and, as a result, should be regarded as the fourth generation of MOSFET models. Based on the core of the MM11 model, we have developed new concepts to compute the exact value of the surface potential, i.e. accounting for the quantum effects. The model covers all operating regions from accumulation to inversion and is valid for all bias conditions. The VHDL-AMS implementation of the model is then demonstrated and a representative set of simulation results is presented. The computation of charges, transcapacitances and drain current shows an excellent behaviour in terms of accuracy and speed, while requiring no additional parameter in comparison to a classical model. Comparison with experimental data from a current deep-submicron technology is also provided. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new surface-potential-based MOSFET model that independently accounts for the quantum mechanical effects (QME) in the accumulation and inversion regions is proposed. The quantum modeling of the accumulation layer relies on the triangular potential well approximation whereas the variational approach to the solution of the Schro¨dinger and Poisson equations is used for the inversion layer. Using no additional parameter, our quantum relationships offer simple expressions in terms of process parameters and bias. The resulting model is fully dependent on all terminal voltages and gives an accurate description of the surface potential and its derivatives in all regions of operation, from accumulation to inversion. The results of this compact model are compared with both self-consistent solutions of Schro¨dinger and Poisson equations, and experimental data. An excellent agreement is found for both I–V and C–V characteristics. [Copyright &y& Elsevier]

A new solution to account for the quantum mechanical effects (QME) in an explicit surface-potential-based MOSFET model is presented. The inclusion of QME is achieved using a variational approach to the solution of the Schro¨dinger and Poisson equations. The resulting physics-based model is fully analytical and suitable for the simulation of deep-submicron MOSFETs, with highly doped substrates and ultra-thin gate oxide thicknesses. It gives an accurate and continuous description of the surface potential and its derivatives from depletion to strong inversion region. An important point is that the model is developed for a MOSFET device, and not only for a MOS capacitor, so it is fully dependent on all terminal voltages. The quantum explicit surface potential model leads to excellent results in comparison with full QM self-consistent calculations (coupled Schro¨dinger–Poisson simulations) for a large range of substrate doping and oxide thickness. Comparisons with experimental data from various deep-submicron CMOS technologies show accurate fits for both I–V and C–V characteristics. [Copyright &y& Elsevier]

Estimation of parasitic capacitances in a MOSFET device is very important, notably in mixed circuit simulation. For deep-submicron LDD MOSFETs, the extrinsic capacitance (overlap plus fringing capacitances) is a growing fraction of the total gate capacitance. A correct estimation of the extrinsic capacitance requires an accurate modeling of each of its constituents. However the major existing models do not correctly predict the overlap capacitance and the inner fringing capacitance (which is often ignored). In this paper a new approach to model the overlap Cov and fringing Cif+Cof capacitances in the zero-current regime is presented. The bias dependence of the extrinsic capacitance is investigated and a detailed study of the influence of the LDD doping dose is also undertaken. Then, an efficient, simple and continuous model describing the evolution of overlap and fringing capacitances in all operating regimes of a n-channel LDD MOSFET is developed. Finally this model is incorporated in an existing compact-model for circuit simulation. It is shown that this new model leads to excellent results in comparison with full 2D numerical device simulation. [Copyright &y& Elsevier]

In recent years, a lot of attention has been paid to carbon nanotube (CNT) networks and their applications to electronic devices. Many studies concentrate on the percolation threshold and the characterization of the conduction in such materials. Nevertheless, no theoretical study has yet attempted to characterize the CNT features inside finite size CNT networks. We present a theoretical approach based on geometrical and statistical considerations. We demonstrate the possibility of explicitly determining some relations existing between two neighbor CNTs and their contact efficiency in random networks of identical CNTs. We calculate the contact probability of rigid identical CNTs and we obtain a probability of 0.2027, which turns out to be independent of the CNT density. Based on this probability, we establish also the dependence of the number of contacts per CNT as a function of the CNT density. All the theoretical results are validated by very good agreement with Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

The interaction of a ligand with a macromolecule has been modeled following different theories. The tenants of the induced fit model consider that upon ligand binding, the protein–ligand complex undergoes a conformational change. In contrast, the allosteric model assumes that only one among different coexisting conformers of a given protein is suitable to bind the ligand optimally. In the present paper, we propose a general framework to model the binding of ligands to a macromolecule. Such framework built on the binding polynomial allows opening new ways to teach in a unified manner ligand binding, enzymology and receptor binding in pharmacology. Moreover, we have developed simple software that allows building the binding polynomial from the schematic description of the biological system under study. Taking calmodulin as a canonical example, we show here that the proposed tool allows the easy retrieval of previously experimental and computational reports. This article is part of a Special Issue entitled: Calcium Signaling in Health and Disease. Guest Editors: Geert Bultynck, Jacques Haiech, Claus W. Heizmann, Joachim Krebs, and Marc Moreau. [ABSTRACT FROM AUTHOR]

Synthetic biology is an emerging science that aims to create new biological functions that do not exist in nature, based on the knowledge acquired in life science over the last century. Since the beginning of this century, several projects in synthetic biology have emerged. The complexity of the developed artificial bio-functions is relatively low so that empirical design methods could be used for the design process. Nevertheless, with the increasing complexity of biological circuits, this is no longer the case and a large number of computer aided design softwares have been developed in the past few years. These tools include languages for the behavioral description and the mathematical modelling of biological systems, simulators at different levels of abstraction, libraries of biological devices and circuit design automation algorithms. All of these tools already exist in other fields of engineering sciences, particularly in microelectronics. This is the approach that is put forward in this paper., (© 2017 médecine/sciences – Inserm.)

This paper deals with the development of a new simulator that will be very helpful to establish new accurate and predictive design-oriented models for the BioBricks used in synthetic biology. The simulator uses the principle of the game-of-life: molecules can move on a grid and, at every iteration, binding and dissociation rules are applied when two molecules are on same node. The principle is elementary but it can highlight interesting biological phenomenon. Those can be modeled by mathematical equations to achieve design-oriented models. In this case, the simulator also helps to make to link between mathematical parameters and the microscopic parameters. A first version of the software has been implemented in MATLAB. It permits to retrieve very interesting results, such as the Hill's equation and the properties of Hill's coefficient.