Deviation of threshold voltage and effective mobility due to random dopant fluctuation is proposed.An improved 65 nm average drain current MOS model calledαlaw is utilized after fitting HSPICE simulating data and ext...Deviation of threshold voltage and effective mobility due to random dopant fluctuation is proposed.An improved 65 nm average drain current MOS model calledαlaw is utilized after fitting HSPICE simulating data and extracting process parameters.Then,a current mismatch model of nanoscale MOSFETs induced by random dopant fluctuation is presented based on propagation of variation theory.In test conditions,the calculated standard deviation applying this model,compared to 100 times Monte-Carlo simulation data with HSPICE,indicates that the average relative error and relative standard deviation is 0.24%and 0.22%,respectively.The results show that this mismatch model is effective to illustrate the physical mechanism,as well as being simple and accurate.展开更多
A new mathematical model, fluctuation spectrum random trajectory model (FSRTM) for the particle motion in environmental fluid was developed using Lagrangian method, in which the time mean velocity of the fluid was ca...A new mathematical model, fluctuation spectrum random trajectory model (FSRTM) for the particle motion in environmental fluid was developed using Lagrangian method, in which the time mean velocity of the fluid was calculated by a time mean velocity formula for two dimensional homogeneous shear turbulent flows in open channel, the velocity fluctuation of the fluid was determined by Fourier expansion and fluctuation spectrum, and the particle motion equation was solved using Ronge Kutta method. For comparison, the spherical cation exchange resins with a density of 1 44 g/cm\+3 and diameters ranging from 0 50—0 60 mm, 0 60—0 70 mm and 0 80—0 90 mm were selected as the experimental solid particles, and their moving velocities and trajectories in shear turbulent flows with the flow Reynolds number of 4710, 10240, 11900 and 20760 were investigated. The comparing analyses of the modeled results with the measured results have shown that the model developed in this paper can describe the motions of the particles in shear turbulent flow.展开更多
We propose a unique approach for realizing dopingless impact ionization MOS (DL-IMOS) based on the charge plasma concept as a remedy for complex process flow. It uses work-function engineering of electrodes to form ...We propose a unique approach for realizing dopingless impact ionization MOS (DL-IMOS) based on the charge plasma concept as a remedy for complex process flow. It uses work-function engineering of electrodes to form charge plasma as surrogate doping. This charge plasma induces a uniform p-region in the source side and an n-region in the drain side on intrinsic silicon film with a thickness less than the intrinsic Debye length. DL-IMOS offers a simple fabrication process flow as it avoids the need of ion implantation, photo masking and complicated thermal budget via annealing devices. The lower thermal budget is required for DL-IMOS fabrication enables its fabrication on single crystal silicon-on-glass substrate realized by wafer scale epitaxial transfer. It is highly immune to process variations, doping control issues and random dopant fluctuations, while retaining the inherent advantages of conventional IMOS. To epitomize the fabrication process flow for the proposed device a virtual fabrication flow is also proposed here. Extensive device simulation of the major device performance metrics such as subthreshold slope, threshold voltage, drain induced current enhancement, and breakdown voltage have been done for a wide range of electrodes work-function. To evaluate the potential applications of the proposed device at circuit level, its mixed mode simulations are also carried out.展开更多
文摘Deviation of threshold voltage and effective mobility due to random dopant fluctuation is proposed.An improved 65 nm average drain current MOS model calledαlaw is utilized after fitting HSPICE simulating data and extracting process parameters.Then,a current mismatch model of nanoscale MOSFETs induced by random dopant fluctuation is presented based on propagation of variation theory.In test conditions,the calculated standard deviation applying this model,compared to 100 times Monte-Carlo simulation data with HSPICE,indicates that the average relative error and relative standard deviation is 0.24%and 0.22%,respectively.The results show that this mismatch model is effective to illustrate the physical mechanism,as well as being simple and accurate.
文摘A new mathematical model, fluctuation spectrum random trajectory model (FSRTM) for the particle motion in environmental fluid was developed using Lagrangian method, in which the time mean velocity of the fluid was calculated by a time mean velocity formula for two dimensional homogeneous shear turbulent flows in open channel, the velocity fluctuation of the fluid was determined by Fourier expansion and fluctuation spectrum, and the particle motion equation was solved using Ronge Kutta method. For comparison, the spherical cation exchange resins with a density of 1 44 g/cm\+3 and diameters ranging from 0 50—0 60 mm, 0 60—0 70 mm and 0 80—0 90 mm were selected as the experimental solid particles, and their moving velocities and trajectories in shear turbulent flows with the flow Reynolds number of 4710, 10240, 11900 and 20760 were investigated. The comparing analyses of the modeled results with the measured results have shown that the model developed in this paper can describe the motions of the particles in shear turbulent flow.
文摘We propose a unique approach for realizing dopingless impact ionization MOS (DL-IMOS) based on the charge plasma concept as a remedy for complex process flow. It uses work-function engineering of electrodes to form charge plasma as surrogate doping. This charge plasma induces a uniform p-region in the source side and an n-region in the drain side on intrinsic silicon film with a thickness less than the intrinsic Debye length. DL-IMOS offers a simple fabrication process flow as it avoids the need of ion implantation, photo masking and complicated thermal budget via annealing devices. The lower thermal budget is required for DL-IMOS fabrication enables its fabrication on single crystal silicon-on-glass substrate realized by wafer scale epitaxial transfer. It is highly immune to process variations, doping control issues and random dopant fluctuations, while retaining the inherent advantages of conventional IMOS. To epitomize the fabrication process flow for the proposed device a virtual fabrication flow is also proposed here. Extensive device simulation of the major device performance metrics such as subthreshold slope, threshold voltage, drain induced current enhancement, and breakdown voltage have been done for a wide range of electrodes work-function. To evaluate the potential applications of the proposed device at circuit level, its mixed mode simulations are also carried out.