Non-quasi-static small-signal modeling and analytical parameter extraction of SOI FinFETs

Accurate modeling and analytical parameter extraction of the non-quasi-static small-signal model of FinFETs are presented using a three-dimensional device simulator. Using simple Y- and Z-matrices calculations, the extrinsic gate-to-drain/source capacitance and source/drain resistance are de-embedded from the small-signal equivalent circuit. The analytical parameter extractions are performed by Y-parameter analysis after removing the extrinsic gate-to-drain/source capacitance and source/drain resistance. Accuracy of the model and extraction method is verified with the device-simulation data up to 700 GHz. Without any complex fitting and optimization steps, the total modeling rms error of the Y-parameter up to 700 GHz was calculated to be only 1.9 % in the saturation region and 2.1 % in the linear region. Also, the bias dependencies of the small-signal parameters are presented.     

A unified drain current model for nanoscale double-gate and surrounding-gate MOSFETs incorporating velocity saturation

A unified drain current model for undoped or lightly doped symmetric double-gate and surrounding-gate MOSFETs incorporating velocity saturation effect is proposed in this paper. The unified charge-based core model for undoped or lightly doped double-gate and surrounding-gate MOSFETs is presented first based on the previously published separate models. Caughey-Thomas engineering mobility model with its exponent factor n = 2 is then integrated self-consistently into the unified drain current model development of the two device structures. Extensive two dimensional and three dimensional device simulations are performed to validate the proposed model. Good agreements of the output and transfer characteristics between the unified model and the numerical simulations are obtained for both the double-gate and surrounding-gate MOSFETs. Symmetry property of the proposed unified current model is obtained with the exponent factor n = 2 in Cauhey-Thomas Model.     

SOI MOSFET with an insulator region (IR-SOI): A novel device for reliable nanoscale CMOS circuits

Device performance in the electronic circuits degrades with elapsed time. Therefore it is important to design a new device to have a reliable performance. In this paper, we present the unique features exhibited by a novel nanoscale silicon-on-insulator (SOI) metal-oxide-semiconductor field effect transistor (MOSFET) in which the silicon active layer consists of an insulator region (IR-SOI). The high-K dielectric HfO₂ as an insulator material is located in the silicon active layer and drain region. Our simulation results demonstrate that this leads to improve the hot electron reliability of the IR-SOI in comparison with the conventional SOI-MOSFET (C-SOI). The insulator region HfO₂ considerably decreases the electric field in the channel and drain regions. Therefore, the degradation mechanism in the proposed structure is lower than that in the C-SOI structure because of reduction of hot carrier effect (HCE). Also using two-dimensional and two-carrier device simulation, we have investigated the improvement in device performance focusing on the HCE, off current, gate current and gate induced drain leakage (GIDL) which can effect on the reliability of the CMOS devices.     

Bare-eye view at the nanoscale: new visual interferometric multi-indicator (VIMI)

By exploiting the interferometric antireflection action of a probe sample, consisting of a diamond-like carbon (DLC) film grown on Si, combined with a specific illumination spectrum, we designed and constructed an optical device for the visual remote sensing of radiation (either plasma or atomic oxygen) and for the visual inspection of adsorbed organic contamination as thin as a few molecular layers. The capabilities of this new visual interferometric multi-indicator (VIMI) enable the bare-eye color detection of thickness changes on the order of a few nanometers without the intervention of any instrumental or computer interface.     

Fuzzy modeling and simulation for lead removal using micellar-enhanced ultrafiltration (MEUF)

In the present paper, a three factor, three-level response surface design based on Box-Behnken design (BBD) was developed for maximizing lead removal from aqueous solution using micellar-enhanced ultrafiltration (MEUF). Due to extremely complexity and nonlinearity of membrane separation processes, fuzzy logic (FL) models have been driven to simulate MEUF process under a wide range of initial and hydrodynamic conditions. Instead of using mathematical model, fuzzy logic approach provides a simpler and easier approach to describe the relationships between the processing variables and the metal rejection and permeation flux. Statistical values, which quantify the degree of agreement between experimental observations and numerically calculated values, were found greater than 91% for all cases. The results show that predicted values obtained from the fuzzy model were in very good agreement with the reported experimental data.     

A new analytical method for particulate composites

A new semi-analytical approach to predict the mechanical behavior of heterogeneous (composite) media is presented. The eigenfunctions for the governing partial differential equation that the composite is subject to are derived in series form. The permissible functions that satisfy the continuity condition across the interface as well as the homogeneous boundary condition are obtained with the help of a computer algebra system. The Green’s function for the composite is then constructed from the eigenfunctions. Using the Green’s function, the physical/mechanical field in the composite is expressed. Numerical examples are shown.     

新型船用气体稳压器启动充气过程的建模及仿真研究

基于船用核动力一体化反应堆结构的需要，建立了新型船用气体稳压器启动充气过程的数学模型，并进行了仿真计算．计算结果表明，该模型能正确地描述该型稳压器实际的启动充气过程，满足工程设计及系统研究的需要．     

A SPICE-compatible model for nanoscale MOSFET capacitor simulation under the inversion condition

A SPICE-compatible charge model for nanoscale MOSFET is proposed. Based on the solution of Schrodinger-Poisson (S-P) equations, the developed compact charge model is optimized with respect to: 1) the position of the charge concentration peak; 2) the maximum of the charge concentration; 3) the total inversion charge sheet density; and 4) the average inversion charge depth, respectively. This model can predict inversion layer electron density for various oxide thicknesses and applied voltages. Compared to the S-P results, our model prediction is within 5% of accuracy. Application of this charge quantization model to the C-V measurement produces an excellent agreement. This compact model has continuous derivatives and is therefore amenable to a device simulator. It can also be easily incorporated into circuit simulator for modeling ultrathin oxide MOSFET C-V characteristics.     

Compressive behavior of tailor-made metallic foams (TMFs): Numerical simulation and statistical modeling

In this work, the compressive behavior of tailor-made metallic foams (TMFs) was qualified and quantified under quasi-static compressive loading. Response surface methodology (RSM) based on a central composite design (CCD) was successfully employed for development quadratic polynomial regression models between the response variables (structural stiffness, yield and compressive strength) in terms of three variables (cell size, cell wall thickness and height of cell layers). These models were then used for finite element simulation of TMFs under compression conditions by considering a representative unit cell. There was an adequate agreement between the simulation data and the experimental measurements within 3.5% confidence interval. The analysis of the statistically developed models revealed that ratio of wall thickness to the size of cell (t/D) has the most significant influence on the compressive behavior of TMFs.     

SOI光电子集成

SOI（Silicon-on-Insulator)光电子集成已成为十分引人注目的研究课题，其工艺与CMOS工艺完全兼容，可以实现低成本的SOI基整片集成光电子回路。本文综述了近几年来SOI集成光电子器件的发展以及一些最新的研究进展，着重分析几种最新型光无源器件的工作原理和结构，包括SOI光波导、SOI光波导耦合器、SOI光波导开关、相位阵列波导光栅（PAWG）、基于SOI的光探测器等，并介绍了中国科学院半导体所集成光电子国家重点实验室的研究进展。     

A new analytical method for complete six-port reflectometercalibration

A novel procedure is described for the calibration of an arbitrary six-port reflectometer. The analytical method reduces the six-port to a four-port, but in contrast to Engen (see IEEE Trans. Microwave Theory Tech., vol.MTT-26, p.951-957, Dec. 1978) for the symmetric determination of the six- to four-port reduction parameters, only five reflective terminations are necessary with their reflection coefficient lying on the same circle of unknown amplitude and phase position (e.g. a sliding short). In contrast to most other procedures, all equations resulting from suitable substitutions are linearly independent, and therefore no restrictions on the six-port design are necessary. The calibration steps were verified by a six-port simulation. Experimental results measured with a W-band (90-100 GHz) six-port using diode detectors demonstrate the capability of this procedure     

A molecular dynamics simulation study on trapping ions in a nanoscale Paul trap

We found by molecular dynamics simulations that a low energy ion can be trapped effectively in a nanoscale Paul trap in both vacuum and aqueous environments when appropriate AC/DC electric fields are applied to the system. Using the negatively charged chlorine ion as an example, we show that the trapped ion oscillates around the center of the nanotrap with an amplitude dependent on the parameters of the system and applied voltages. Successful trapping of the ion within nanoseconds requires an electric bias of GHz frequency, in the range of hundreds of mV. The oscillations are damped in the aqueous environment, but polarization of water molecules requires the application of a higher voltage bias to reach improved stability of the trapping. Application of a supplemental DC driving field along the trap axis can effectively drive the ion off the trap center and out of the trap, opening up the possibility of studying DNA and other charged molecules using embedded probes while achieving a full control of their translocation and localization in the trap.     

Characterization and modeling of breaking-induced spontaneous nanoscale periodic stripes in metallic glasses

Stripes with a period of 87 nm appear in the mirror region of the fracture surface of metallic glasses. Two competing failure mechanisms of immediate meniscus instability and cavitation mechanism near the crack tip control the fracture process of metallic glasses and the formation process of nanostripes.     

风格化和新的造型语言与表达方式--新媒体系统与平面设计重构的思考

以计算机为平台的设计新媒体,绝不是简简单单的辅助设计工具而已,计算机所带来的革命和那种无穷无尽的探索的可能性,都是杰出的也是无比重要的.它对当代平面设计的造型语言、表达方式、方法的改变首先体现在设计工具的重构与组合,其次每一个设计师都可以使新媒体设计系统具有风格化的使用特点.     

基于Agent的水声对抗仿真系统建模与仿真分析

分析了水声对抗仿真系统的组成和特点,基于Agent方法进行了水声对抗仿真建模,建立了Agent实体的功能层、信息层和认知层的模型结构,给出了基于Agent的系统结构和个体Agent的建模过程,从一个新的视点上研究了水声对抗分布仿真系统,最后总结了这种仿真体系的特点和长处。     

Error and uncertainty in modeling and simulation

This article develops a general framework for identifying error and uncertainty in computational simulations that deal with the numerical solution of a set of partial differential equations (PDEs). A comprehensive, new view of the general phases of modeling and simulation is proposed, consisting of the following phases: conceptual modeling of the physical system, mathematical modeling of the conceptual model, discretization and algorithm selection for the mathematical model, computer programming of the discrete model, numerical solution of the computer program model, and representation of the numerical solution. Our view incorporates the modeling and simulation phases that are recognized in the systems engineering and operations research communities, but it adds phases that are specific to the numerical solution of PDEs. In each of these phases, general sources of uncertainty, both aleatory and epistemic, and error are identified. Our general framework is applicable to any numerical discretization procedure for solving ODEs or PDEs. To demonstrate this framework, we describe a system-level example: the flight of an unguided, rocket-boosted, aircraft-launched missile. This example is discussed in detail at each of the six phases of modeling and simulation. Two alternative models of the flight dynamics are considered, along with aleatory uncertainty of the initial mass of the missile and epistemic uncertainty in the thrust of the rocket motor. We also investigate the interaction of modeling uncertainties and numerical integration error in the solution of the ordinary differential equations for the flight dynamics.     

PDSOI NMOS/CMOS闩锁特性

本文研究了部分耗尽绝缘体上的硅(PDSOI)NMOS、CMOS结构的闩锁(latch)特性。提出了一种体电极触发诱发PDSOI NMOS器件闩锁效应维持电压的测试方法,并用此方法测试出了不同栅长、栅宽和体接触结构NMOS/CMOS的闩锁效应维持电压,以及沟道注入条件和温度对维持电压的影响。     

SOI的自加热效应与SOI新结构的研究

阐述了自加热效应产生的原因以及它对SOI电路的影响，并介绍了为克服自加热效应和满足某些特殊器件和电路的要求，国内外正在竞相探索研究的新型SOI结构，如SOIM，Silicon onAlN,GPSOI,SiCOI,GeSiOI,SON,SSOI等，结论SOI新结构制备工作，报道了SOI的自加热效应及其新结构的研究进展。