基于Statz模型的射频MOSFET非线性电容建模

Nonlinear Capacitance Modeling of Radio Frequency MOSFETs Based on the Statz Model

研究了Statz模型对于表征射频(RF)金属氧化物半导体场效应晶体管(MOSFET)器件特性的适用情况,并提出了一个MOSFET非线性电容改进模型。对英飞凌公司生产的规格为4×0.6μm×18(栅指数×栅宽×元胞数)、栅长为90 nm的MOSFET进行S参数实验测量。经过去嵌剥离所有寄生元件后,在多个偏置条件下分别使用小信号等效电路模型提取出MOSFET非线性栅源电容C_(gs)和栅漏电容C_(gd)的数据;对比了传统Statz模型以及改进模型的仿真结果与实验测量数据的相对误差。仿真结果和误差分析表明改进模型与实验测量数据吻合很好,在大部分工作范围内误差控制在5%以下,证明改进模型适用于表征MOSFET的非线性电容特性。

The applicability of the Statz model to characterize the characteristics of radio frequency(RF)metal-oxide-semiconductor field-effect-transistors(MOSFETs)was studied,and an improved model of MOSFET nonlinear capacitance was proposed.S parameters were measured on a 90 nm gate length MOSFET fabricated by Infineon Technologies with a specification of 4×0.6μm×18(number of gate fingers×gate width×number of unit cells).After de-embedding and stripping off all parasitic components,a small signal equivalent circuit model was applied to extract the nonlinear gate-to-source capacitance Cgs and gate-to-drain capacitence Cgd data under multiple bias conditions.The relative errors of the simulation results and experimental data between the traditional Statz model and the improved model were compared.The simulation results and error analysis show that the data of the improved model are well agree with the experimental data,and the error is controlled below 5%in most working range,which proves that the improved model is suitable to characterize the nonlinear capacitance characteristics of MOSFETs.