Based on the quasi-two-dimensional （2D） solution of Poisson＇s equation in two continuous channel regions, an an- alytical threshold voltage model for short-channel junctionless dual-material cylindrical surrounding...Based on the quasi-two-dimensional （2D） solution of Poisson＇s equation in two continuous channel regions, an an- alytical threshold voltage model for short-channel junctionless dual-material cylindrical surrounding-gate （JLDMCSG） metal-oxide-semiconductor field-effect transistor （MOSFET） is developed. Using the derived model, channel potential dis- tribu6o~, h~riz~atal electrical ~eld distributign, a~d threshold v~ltage roll-off of ~LDMCSG MOSFET are in,instigated. Compared with junctionless single-material CSG （JLSGCSG） MOSFET~ JLDMCSG MOSFET can effectively suppress short-channel effects and simultaneously improve carrier transport efficiency. It is also revealed that threshold voltage roll- off of JLDMCSG can be significantly reduced by adopting both a small oxide thickness and a small silicon channel radius. The model is verified by comparing its calculated results with that obtained from three-dimensional （3D） numerical device simulator ISE.展开更多
A two-dimensional analytical subthreshold behavior model for junctionless dual-material cylindrical surrounding- gate （JLDMCSG） metal-oxide-semiconductor field-effect transistors （MOSFETs） is proposed. It is deriv...A two-dimensional analytical subthreshold behavior model for junctionless dual-material cylindrical surrounding- gate （JLDMCSG） metal-oxide-semiconductor field-effect transistors （MOSFETs） is proposed. It is derived by solving the two-dimensional Poisson＇s equation in two continuous cylindrical regions with any simplifying assumption. Using this analytical model, the subthreshold characteristics of JLDMCSG MOSFETs are investigated in terms of channel electro- static potential, horizontal electric field, and subthreshold current. Compared to junctionless single-material cylindrical surrounding-gate MOSFETs, JLDMCSG MOSFETs can effectively suppress short-channel effects and simultaneously im- prove carrier transport efficiency. It is found that the subthreshold current of JLDMCSG MOSFETs can be significantly reduced by adopting both a thin oxide and thin silicon channel. The accuracy of the analytical model is verified by its good agreement with the three-dimensional numerical simulator ISE TCAD.展开更多
Particle charge density is vitally important for monitoring electrostatic charges and understanding particle charging behavior in fluidized beds. In this paper, a dual-material probe was tested in a gas-solid fluidize...Particle charge density is vitally important for monitoring electrostatic charges and understanding particle charging behavior in fluidized beds. In this paper, a dual-material probe was tested in a gas-solid fluidized bed for measuring the charge density of fluidized particles. The experiments were conducted in a two-dimensional fluidized bed with both single bubble injection and freely bubbling, at various particle charge densities and superficial gas velocities. Uniformly sized glass beads were used to eliminate complicating factors at this early stage of probe development. Peak currents, extracted from dynamic signals, were decoupled to determine charge densities of bed particles, which were found to be qualitatively and quantitatively consistent with charge densities directly measured by Faraday cup from the freely bubbling fluidized bed. The current signals were also decoupled to estimate bubble rise velocities, which were found to be in reasonable agreement with those obtained directly by analyzing video images.展开更多
For the first time,a simple and accurate two-dimensional analytical model for the surface potential variation along the channel in fully depleted dual-material gate strained-Si-on-insulator（DMG SSOI） MOSFETs is deve...For the first time,a simple and accurate two-dimensional analytical model for the surface potential variation along the channel in fully depleted dual-material gate strained-Si-on-insulator（DMG SSOI） MOSFETs is developed.We investigate the improved short channel effect（SCE）,hot carrier effect（HCE）,drain-induced barrier-lowering（DIBL） and carrier transport efficiency for the novel structure MOSFET.The analytical model takes into account the effects of different metal gate lengths,work functions,the drain bias and Ge mole fraction in the relaxed SiGe buffer.The surface potential in the channel region exhibits a step potential,which can suppress SCE,HCE and DIBL.Also,strained-Si and SOI structure can improve the carrier transport efficiency,with strained-Si being particularly effective.Further, the threshold voltage model correctly predicts a＂rollup＂in threshold voltage with decreasing channel length ratios or Ge mole fraction in the relaxed SiGe buffer.The validity of the two-dimensional analytical model is verified using numerical simulations.展开更多
A two-dimensional(2D)model for the subthreshold current in the dual-material gate(DMG)siliconon-insulator(SOI)MOSFET with a single halo is presented.The model considers single halo doping in the channel near the sourc...A two-dimensional(2D)model for the subthreshold current in the dual-material gate(DMG)siliconon-insulator(SOI)MOSFET with a single halo is presented.The model considers single halo doping in the channel near the source and a dual-material gate to derive the channel potential using the explicit solution of the 2D Poisson’s equation.Together with the conventional driftdiffusion theory,this results in the development of a subthreshold current model for the novel structure.Model verification is carried out using the 2D device simulator ISE.Excellent agreement is obtained between the calculations and the simulated results of the model.展开更多
基金Project supported by the National Natural Science Foundation of China （Grant Nos. 61204092 and 61076101） and the Fundamental Research Funds for the Central Universities of Ministry of Education of China （Grant No. K50511250001 ）.
文摘Based on the quasi-two-dimensional （2D） solution of Poisson＇s equation in two continuous channel regions, an an- alytical threshold voltage model for short-channel junctionless dual-material cylindrical surrounding-gate （JLDMCSG） metal-oxide-semiconductor field-effect transistor （MOSFET） is developed. Using the derived model, channel potential dis- tribu6o~, h~riz~atal electrical ~eld distributign, a~d threshold v~ltage roll-off of ~LDMCSG MOSFET are in,instigated. Compared with junctionless single-material CSG （JLSGCSG） MOSFET~ JLDMCSG MOSFET can effectively suppress short-channel effects and simultaneously improve carrier transport efficiency. It is also revealed that threshold voltage roll- off of JLDMCSG can be significantly reduced by adopting both a small oxide thickness and a small silicon channel radius. The model is verified by comparing its calculated results with that obtained from three-dimensional （3D） numerical device simulator ISE.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61204092 and 61076101)the Fundamental Research Funds for the Central Universities of Ministry of Education of China(Grant No.K50511250001)
文摘A two-dimensional analytical subthreshold behavior model for junctionless dual-material cylindrical surrounding- gate （JLDMCSG） metal-oxide-semiconductor field-effect transistors （MOSFETs） is proposed. It is derived by solving the two-dimensional Poisson＇s equation in two continuous cylindrical regions with any simplifying assumption. Using this analytical model, the subthreshold characteristics of JLDMCSG MOSFETs are investigated in terms of channel electro- static potential, horizontal electric field, and subthreshold current. Compared to junctionless single-material cylindrical surrounding-gate MOSFETs, JLDMCSG MOSFETs can effectively suppress short-channel effects and simultaneously im- prove carrier transport efficiency. It is found that the subthreshold current of JLDMCSG MOSFETs can be significantly reduced by adopting both a thin oxide and thin silicon channel. The accuracy of the analytical model is verified by its good agreement with the three-dimensional numerical simulator ISE TCAD.
基金NOVA Chemicals Corporation and the Natural Sciences and Engineering Research Council(NSERC) of Canada for financial assistance via the Collaborative Research and Development(CRD) program
文摘Particle charge density is vitally important for monitoring electrostatic charges and understanding particle charging behavior in fluidized beds. In this paper, a dual-material probe was tested in a gas-solid fluidized bed for measuring the charge density of fluidized particles. The experiments were conducted in a two-dimensional fluidized bed with both single bubble injection and freely bubbling, at various particle charge densities and superficial gas velocities. Uniformly sized glass beads were used to eliminate complicating factors at this early stage of probe development. Peak currents, extracted from dynamic signals, were decoupled to determine charge densities of bed particles, which were found to be qualitatively and quantitatively consistent with charge densities directly measured by Faraday cup from the freely bubbling fluidized bed. The current signals were also decoupled to estimate bubble rise velocities, which were found to be in reasonable agreement with those obtained directly by analyzing video images.
基金Project supported by the National Natural Science Foundation of China(Nos.60976068,60936005)the Cultivation Fund of the Key Scientific and Technical Innovation Project,Ministry of Education of China Program(No.708083)the Specialized Research Fund for the Doctoral Program of Higher Education,China(No.200807010010).
文摘For the first time,a simple and accurate two-dimensional analytical model for the surface potential variation along the channel in fully depleted dual-material gate strained-Si-on-insulator（DMG SSOI） MOSFETs is developed.We investigate the improved short channel effect（SCE）,hot carrier effect（HCE）,drain-induced barrier-lowering（DIBL） and carrier transport efficiency for the novel structure MOSFET.The analytical model takes into account the effects of different metal gate lengths,work functions,the drain bias and Ge mole fraction in the relaxed SiGe buffer.The surface potential in the channel region exhibits a step potential,which can suppress SCE,HCE and DIBL.Also,strained-Si and SOI structure can improve the carrier transport efficiency,with strained-Si being particularly effective.Further, the threshold voltage model correctly predicts a＂rollup＂in threshold voltage with decreasing channel length ratios or Ge mole fraction in the relaxed SiGe buffer.The validity of the two-dimensional analytical model is verified using numerical simulations.
基金supported by the National Natural Science Foundation of China (Grant No.60206006).
文摘A two-dimensional(2D)model for the subthreshold current in the dual-material gate(DMG)siliconon-insulator(SOI)MOSFET with a single halo is presented.The model considers single halo doping in the channel near the source and a dual-material gate to derive the channel potential using the explicit solution of the 2D Poisson’s equation.Together with the conventional driftdiffusion theory,this results in the development of a subthreshold current model for the novel structure.Model verification is carried out using the 2D device simulator ISE.Excellent agreement is obtained between the calculations and the simulated results of the model.
