MESFET和PHEMT大信号建模

分析了 MESFET和 PHEMT大信号建模的现状 ,提出了在 DC和脉冲两种状态下通用于 MESFET和 PHEMT的精确 I-V模型 ;提出了具有二维 C-V模型精度的一维C-V模型和负载线 S参数测量提取方法 ;提出了采用改进 Cold FET测量与提取技术进行管壳封装器件建模的方法。本文的大信号模型具有很好的数值收敛性和标准的等效电路。提出的模型精确地模拟了器件的 DC I-V、脉冲 I-V、偏置相关 S参数、 C-V特性和电路的功率、增益、效率以及线性特性 ,并用几个实例证实了其精度和通用性。     

基于表面电势的高压LDMOS晶体管直流模型改进

针对标准MOSFET的BSIM3和PSP模型在高压LDMOS建模上的不足,提出了基于PSP表面电势方程的改进高压LDMOS晶体管I-V模型.在研究过程中,使用Agilent系列直流测试设备及ICCAP参数提取软件和ADS仿真器对高压LDMOS晶体管进行数据采集及参数提取.在开放的PSP模型Verilog-A代码基础上完成改进代码的实现.最终的结果表明,采用改进后的模型,仿真曲线与测量的I-V曲线十分吻合,该模型大大提高了PSP I-V模型模拟高压LDMOS晶体管时的精确度,对于实用高压集成电路的设计和仿真有着重要意义.     

毫米波GaN HEMT器件大信号模型

介绍了一种毫米波GaN基HEMT器件大信号等效电路模型。该模型采用SDD的建模方法。提出了I-V及C-V表达式,完成了直流及S参数的拟合,并分析了拟合结果。与18GHz的在片loadpull测试结果比较,模型仿真结果显示输出功率及效率与实测数据基本一致。     

一种考虑自热效应的AlGaN/GaN HEMT大信号模型

当AlGaN/GaN HEMT输出高功率密度时,器件沟道温度的升高将引起电流的下降(自热效应).提出了一种针对AlGaN/GaN HEMT改进的大信号等效电路模型,考虑了HEMT自热效应,建立了一种改进的大信号I-V特性模型,仿真结果与测试结果符合较好,提高了大信号模型的精度.     

一种紧凑的GaN高电子迁移率晶体管大信号模型拓扑

GaN高电子迁移率晶体管（HEMT）以其复杂的器件特性使其大信号建模变得十分困难,尽管EEHEMT、Angelov等模型结构曾经成功应用于GaAs HEMT/MESFET的大信号模型,但当它们被用于GaN HEMT建模时却不再准确和完备.面向GaN HEMT器件的大信号模型,本文提出了一种紧凑的模型拓扑,此模型拓扑综合了GaN HEMT器件的直流电压-电流（I-V）特性、非线性电容、寄生参数、栅延迟漏延迟与电流崩塌、自热效应以及噪声等特性.经验证此模型拓扑在仿真中具有很好的收敛性,适用于GaN HEMT器件的大信号模型的建立,满足GaN基微波电路设计对器件模型的需求.     

高压集成电路中的HV MOS晶体管BSIM3 I-V模型改进

针对SPICE BSIM3模型在对大量应用于高压集成电路中的轻掺杂漏高压MOS(简称HV MOS)晶体管建模上的不足,提出了基于BSIM3的高压MOS晶体管I-V模型改进.研究中使用Agilent ICCAP测量系统对HVMOS晶体管进行数据采集,并分析其源漏电阻受栅源、源漏和衬底电压的影响及与标准工艺低压MOS晶体管的差异,针对BSIM3模型源代码中源漏电阻R ds的相关参数算法进行了改进,保留BSIM3v3原有参数的同时增加了R ds的二次栅压调制因子Prwg2和有效Vas参数δ的栅压调制因子δ1,δ2,在开放的SPICE和BSIM3v3源代码上对模型库文件进行修改并实现了优化.仿真结果表明采用改进后的模型,在ICCAP下的测量曲线与参数提取后的I-V仿真曲线十分吻合,该模型大大提高了BSIM3 I-V模型模拟HV MOS晶体管时的精确度,对于高压集成电路的设计与仿真有着极其重要的意义.     

高压集成电路中的HV MOS晶体管BSIM3 I-V模型改进

针对SPICE BSIM3模型在对大量应用于高压集成电路中的轻掺杂漏高压MOS(简称HV MOS)晶体管建模上的不足,提出了基于BSIM3的高压MOS晶体管I-V模型改进.研究中使用Agilent ICCAP测量系统对HVMOS晶体管进行数据采集,并分析其源漏电阻受栅源、源漏和衬底电压的影响及与标准工艺低压MOS晶体管的差异,针对BSIM3模型源代码中源漏电阻R ds的相关参数算法进行了改进,保留BSIM3v3原有参数的同时增加了R ds的二次栅压调制因子Prwg2和有效Vas参数δ的栅压调制因子δ1,δ2,在开放的SPICE和BSIM3v3源代码上对模型库文件进行修改并实现了优化.仿真结果表明采用改进后的模型,在ICCAP下的测量曲线与参数提取后的I-V仿真曲线十分吻合,该模型大大提高了BSIM3 I-V模型模拟HV MOS晶体管时的精确度,对于高压集成电路的设计与仿真有着极其重要的意义.     

光纤陀螺随机漂移的建模与滤波研究

时间序列模型是对光纤陀螺(FOG)随机漂移进行建模的一种重要方法.传统的时间序列建模方法难以应用于实时建模,且模型精度较低.因此,提出了适用于高精度FOG随机漂移的改进自回归整合移动平均模型(ARIMA),并基于该模型建立了FOG随机漂移的实时Kalman滤波器.实验结果表明,该改进ARIMA模型能较准确地描述FOG的随机漂移;Allan方差分析结果表明,与基于传统自回归移动平均模型(ARMA)的Kalman滤波结果相比,基于该模型的Kalman滤波对减小光纤陀螺的5项主要随机误差更有效.     

大栅宽功率器件的分布性研究

随着器件工作频率的升高,以集总元件模型描述大栅宽功率器件引入的误差将越来越大,且这一趋势随着栅长的减小更加显著。对微波大栅宽功率器件的分布性作了初步研究,对传统建模和器件优化方法进行改进,将器件中的有源部分和无源部分分离开,利用微波传输线理论和奇偶模分析对器件的无源部分建模,在满足集总条件时对有源区建模,将两者综合建立了分段的线性模型。与测量结果进行了比较,表明分段模型取得了更为精确的结果;在此基础上又建立了分段的非线性模型,模拟和验证了大栅宽器件的早期非线性现象;最后还提出了功率器件栅宽优化设计的估算方法。     

SiGe HBT小信号和大信号建模与分析北大核心CSCD

基于异质结双极晶体管(HBT)优良的微波特性,精确建模对使用该类器件进行电路设计具有重要的意义。介绍了HBT所具有的独特优越性,采用Gummel-Poon等效电路模型对常用HBT进行了小信号和大信号模型的建立,加入了寄生电感等效衬底寄生参数,测试了SiGe HBT在不同偏置下的S参数及I-V特性曲线,利用半解析方法分析了非线性模型的参数提取,讨论了本征参数和寄生参数的拟合优化。给出了关于HBT大信号和小信号等效电路模型,对比实测参数进行验证,建立模型在测试频率范围内拟合结果和测试结果吻合良好。     

Advanced SPICE-Modeling of 4H-SiC MESFETs

A modified drain source current suitable for simulation program with integrated circuit emphasis （SPICE） simulations of SiC MESFETS is presented in this paper. Accurate modeling of SiC MESFET is achieved by introducing three parameters in Triquint＇s own model （TOM）. The model, which is single piece and continuously differentiable, is verified by measured direct current （DC） I-V curves and scattering parameters （up to 20 GHz）.     

互连封装结构电特性分析中的改进PEEC三维建模

本文提出了一种改进的PEEC模型,为便于在大规模互连封装结构分析中利用规模缩减技术,它以描述系统的状态方程代替了具体的等效电路.为此它以矢量磁位的积分表达式和洛仑兹规范代替了矢量磁位和标量电位的积分表达式,对积分方程进行展开.这样做可以避免复杂介质结构中的电容矩阵提取,大大节省了计算时间.这一模型可方便地嵌入更大的系统进行分层次的综合分析和利用PVL等规模缩减技术.数值计算的结果与其他文献吻合较好,表明该方法有较高的可靠性.     

A bidirectional NMOSFET current reduction model for simulation ofhot-carrier-induced circuit degradation

An approach for modeling hot-electron induced change in drain current that significantly improves the ease of parameter extraction and provides new capabilities for modeling the effect of bidirectional stressing and the asymmetrical I-V characteristics after stressing is presented. The change in the drain current, ΔI_D is implemented as an asymmetrical voltage-controlled current source and the new ΔI_D model is independent of the MOSFET model used for circuit simulation. The physical basis of the model, the analytical model equations, the implementation scheme in BERT (BErkeley Reliability Tools) simulator and simulation results for uni- and bidirectional circuit stressing are presented     

A new I-V model for stress-induced leakage current includinginelastic tunneling

A new I-V model to quantitatively represent stress-induced leakage current (SILC) is presented and compared with the experimental I-V characteristics. The trap-assisted tunneling model is modified so as to include the energy relaxation of tunneling electrons, which has been experimentally verified by applying the carrier separation technique to MOSFETs with the SILC component. The energy relaxation is treated in the new model as the change in the energy level of traps before and after the capture of electrons during two-step tunneling. It is demonstrated that this model successfully represents the experimental I-V characteristics of the SILC component and, particularly, the low apparent barrier height in the Fowler-Nordheim (FN) plot of the SILC component. The calculated low barrier height is attributed to the dominance of direct tunneling mechanism on both tunneling into traps and out of traps. The impact of the energy relaxation during tunneling, used in the present model, on the I-V characteristics is discussed in terms of the trap distribution inside the gate oxide, compared with conventional elastic tunneling model     

An analytic I—V model for lightly doped drain (LDD) MOSFET devices

An analytic I-V model for lightly doped drain (LDD) MOSFET devices is presented. In this model, the n^-region is considered to be a modified buried-channel MOSFET device, and the channel region is considered to be an intrinsic enhancement-mode MOSFET device. Combining the models of these two regions, the drain current in the linear/saturation regions and the saturation voltage can be calculated directly from the terminal voltages. In addition, the parameters used in the channel region can be extracted by a series of least square fittings. According to comparisons between the experimental data measured from the test transistors and the theoretical calculations, the developed I-V model is shown to be valid for wide ranges of channel lengths.     

Direct extraction of an empirical temperature-dependent InGaP/GaAs HBT large-signal model

A new empirical InGaP/GaAs heterojunction bipolar transistor (HBT) large-signal model including self-heating effects is presented. The model accounts for the inherent temperature dependence of the device characteristics due to ambient-temperature variation as well as self-heating. The model is accompanied by a simple extraction process, which requires only dc current-voltage (I-V) and multibias-point small-signal S-parameter measurements. All the current-source model parameters, including the self-heating parameters, are directly extracted from measured forward I-V data at different ambient temperatures. The distributed base-collector capacitance and base resistance are extracted from measured S-parameters using a new technique. The extraction procedure is fast, accurate, and inherently minimizes the average squared-error between measured and modeled data, thereby eliminating the need for further optimization following parameter extraction. This modeling methodology is successfully applied to predict the dc, small-signal S-parameter, and output fundamental and harmonic power characteristics of an InGaP/GaAs HBT, over a wide range of temperatures.     

基于Simulink的混频器建模与仿真

总结了雷达系统仿真的技术现状,指出了基于传统仿真软件建模与仿真的缺点及Simulink在雷达系统仿真中的优势。以雷达系统中的混频器为例,介绍了如何利用Simulink对其进行建模和仿真,并给出了仿真结果和分析。仿真方法具有模型设计过程简单、修改容易和结果直观等特点。该文的工作不但克服了在工作站上用SPW等系统仿真软件进行雷达系统仿真投入大、推广难的不足,又克服了利用高级语言编写雷达系统软件通用性差、难度高、周期长的缺点。为今后在Simulink上开发大规模雷达系统仿真模型库和仿真复杂雷达系统打下基础。     

The effects of high doping on the I-V characteristics of athin-film SOI MOSFET

Modifications of the Ortiz-Conde et al., model which take into account either apparent or physical bandgap narrowing have been presented. The influence of high doping effects is investigated by means of a comparison of the modified models with their original, version for various device parameters. It is shown that the inclusion of bandgap narrowing is essential for accurate simulation of I-V characteristics of a SOI MOSFET in the subthreshold and near-threshold regions. A new analytical model with bandgap narrowing has been derived for the subthreshold region     

Modeling of the Josephson fluxonic diode

A forward bias Josephson fluxonic diode exhibits a linear I-V curve whose slope is a function of the Stewart-McCumber loss parameter /spl beta/, the length of the junction, critical current density and the magnitude of the applied control current. This linear I-V curve lacks resonance structure and does not exhibit a flux flow step. A modeling which matches experimental results is presented.     

On the I-V characteristics of floating-gate MOS transistors

The effects of capacitive coupling on the I-V characteristics of floating-gate MOS transistors are described. A set of modified IV equations for these devices is presented and compared with experimental results.