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.

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).

The potential application range of spintronic devices is wide. However, few works were carried out in the field of compact modeling of such devices. The lack of compact models dramatically increases the design complexity of circuits using spintronic devices. In this paper, focus is made on magnetic tunnel junctions (MTJs). It is presented in a set of two papers: the first part deals with the magnetic aspects of the MTJ, whereas the second one covers the electrical aspects. In this part, a dynamic magnetization model inspired from the micromagnetic formalism is presented. This vectorial model is able to describe the quiescent state, as well as the transient behavior of the magnetization vector of an anisotropic single-domain element. The dynamic magnetization model is implemented in VHDL-AMS and requires only eight parameters. Simulation results are also presented and compared with theoretical ones.

The potential application range of spintronic devices is wide. However, a few works were carried out in the field of compact modeling of such devices. The lack of compact models dramatically increases the design complexity of circuits using spintronic devices. In this paper, focus is made on magnetic tunnel junctions (MTJs). It is presented in a set of two papers: The first part deals with the magnetic aspects of the MTJ, whereas the second one covers the electrical aspects. In this part, the tunneling conduction across the MTJ is modeled using an analytical I-V equation, which is based on previous works on this topic and involves some assumptions that are discussed. The complete compact model is implemented in a very high speed integrated circuit (VHSIC) hardware description language analog mixed signal and includes magnetization aspects presented in the first part. The model requires 25 parameters (19 physical and 6 semiempirical parameters).

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.

Significant progress has been made in the development of magnetic micromanipulation for minimally invasive surgery. The development of systems to localize millimeter-sized robots during magnetic manipulation without line-of-sight detection remains, however, a challenging task. In this study, we focused on the development of a tracking system aiming to fill this gap. A robot which consists of a cylindrical magnet of 1 mm diameter is localized using a 2D array of 3D magnetoresistive sensors. The system, also called magnetic field camera, provides tracking of the robot with a refresh rate of 2 Hz. The developed tracking algorithm reaches a mean absolute error for the position and the orientation of, respectively 0.56 mm and 5.13° in 2D. This system can be added to existing magnetic manipulation systems allowing closed loop control of the navigation. The performances of the magnetic field camera are not affected by an exposure to strong magnetic fields. Exposures up to 3 T have been validated. Increasing the integrability of the magnetic field camera into magnetic manipulation systems. The presented tracking system makes it possible to target applications such as minimally invasive eye surgery or drug delivery. The high spatial and magnetic resolutions allow the tracking of magnetic particles, down to 200 μm diameter, when placed close to the surface. The system could also be suitable for the localization of small objects for 2D biomanipulation.