短沟道金属-氧化物半导体场效应晶体管的散粒噪声模型  

Shot noise model of the short channel metal-oxidesemiconductor field-effect transistor

作　　者：张梦 姚若河[1] 刘玉荣[1] 耿魁伟[1] Zhang Meng;Yao Ruo-He;Liu Yu-Rong;Geng Kui-Wei(School of Electronic and Information Engineering,South China University of Technology,Guangzhou 510641,China)

机构地区：[1]华南理工大学电子与信息学院,广州510641

出　　处：《物理学报》2020年第17期192-200,共9页Acta Physica Sinica

基　　金：广东省重点领域研发计划(批准号:2019B010143003);国家自然科学基金(批准号:61871195)资助的课题.

摘　　要：随着金属-氧化物半导体场效应晶体管(MOSFET)器件的尺寸进入到纳米量级,器件的噪声机理逐渐开始转变.传统的热噪声与漏源电流模型精度出现下降,散粒噪声成为器件噪声不可忽略的因素.本文通过求解能量平衡方程,推导了短沟道MOSFET器件的沟道电子温度和电子速度表达式,由此建立了漏源电流模型;基于漏源电流模型建立了适用于40 nm以下器件的散粒噪声模型和热噪声模型.研究了n型金属-氧化物半导体场效应晶体管(NMOSFET)器件在不同偏置电压下,器件尺寸对散粒噪声抑制因子和噪声机理的影响.研究表明:已有的热噪声模型与散粒噪声模型的精度随着器件尺寸的减小而下降,导致相应的散粒噪声抑制因子被高估.当NMOSFET器件的尺寸减小到10 nm时,器件的噪声需由热噪声与受抑制的散粒噪声共同表征.本文建立的短沟道器件散粒噪声模型可应用于纳米尺寸NMOSFET器件噪声性能的分析与建模.With the development of the semiconductor manufacturing process,the size of the metal-oxidesemiconductor field-effect transistor(MOSFET)device has been on a tens-of-nanometer scale.The shot noise appears in the excess channel noise of the device,and the noise mechanism of the device begins to change gradually.Due to the fact that the electron temperature gradient is neglected in calculation and the significant enhancement of the lateral channel electric field are not taken into consideration,the traditional electron temperature model and the thermal noise model underestimate the effect of hot carrier effects,resulting in the underestimate of the thermal noise.Moreover,the traditional drain-source current model ignores the electron temperature gradient in the calculation and does not include the effect of the electron temperature on the mobility degradation effect either.Therefore,the calculation accuracy of the shot noise and the Fano factor on the basis of the traditional model will be reduced to a certain extent as the size of the device decreases,thus affecting the analysis of the noise mechanism of the device.In this paper,we establish the channel electron temperature model and the electron velocity model by solving the energy balance equation,and develop the drain source current model based on these two models.Moreover,the shot noise model and the thermal noise model suitable for devices below 40 nm are established based on the drain-source current model.Meanwhile,the Fano factor of the shot noise is calculated.The influence of the MOSFET device size on the noise mechanism and the Fano factor of the shot noise are also investigated when the device is under different bias voltages.The results show that the accuracy of the existing thermal noise model and the shot noise model decline as the device size decreases,which eventually leads the Fano factor of the shot noise to be overestimated.When the size of the NMOSFET device is below 20 nm,the shot noise affects the device noise in the strong inversion region.Wi

关 键 词：散粒噪声 抑制因子 电子温度 短沟道 场效应晶体管 

分 类 号：TN386[电子电信—物理电子学]