This article describes the effective channel length degradation under hot carrier stressing. The extraction is based on the IDs-Vcs characteristics by maximum transconductance (maximum slope of IDs & VGS) in the li...This article describes the effective channel length degradation under hot carrier stressing. The extraction is based on the IDs-Vcs characteristics by maximum transconductance (maximum slope of IDs & VGS) in the linear region. The transconductance characteristics are determine for the several devices of difference drawn channel length. The effective channel length of submicron LDD (Lightly Doped Drain) NMOSFETs (Metal Oxide Semiconductor Field Effect Transistor) under hot carrier stressing was measured at the stress time varying from zero to 10,000 seconds. It is shown that the effective channel length was increased with time. This is caused by charges trapping in the oxide during stress. The increased of effective channel length (△Leff) is seem to be increased sharply as the gate channel length is decrease.展开更多
GeSi source/drain structure is purposefully adopted in SOI p MOSFET's to suppress the short channel effect (SCE).The impact of GeSi material (as source only,drain only or both source and drain) on the threshold v...GeSi source/drain structure is purposefully adopted in SOI p MOSFET's to suppress the short channel effect (SCE).The impact of GeSi material (as source only,drain only or both source and drain) on the threshold voltage rolling off and DIBL effect is thoroughly investigated,as well as the influence of the Ge concentration and silicon film thickness.The Ge concentration should be carefully chosen as a tradeoff between the driving current and SCE improvement.The detailed physics is explained.展开更多
An analytical model for the channel potential and the threshold voltage of the short channel dual-material-gate lightly doped drain (DMG-LDD) metal-oxide-semiconductor field-effect transistor (MOSFET) is presented...An analytical model for the channel potential and the threshold voltage of the short channel dual-material-gate lightly doped drain (DMG-LDD) metal-oxide-semiconductor field-effect transistor (MOSFET) is presented using the parabolic approximation method. The proposed model takes into account the effects of the LDD region length, the LDD region doping, the lengths of the gate materials and their respective work functions, along with all the major geometrical parameters of the MOSFET. The impact of the LDD region length, the LDD region doping, and the channel length on the channel potential is studied in detail. Furthermore, the threshold voltage of the device is calculated using the minimum middle channel potential, and the result obtained is compared with the DMG MOSFET threshold voltage to show the improvement in the threshold voltage roll-off. It is shown that the DMG-LDD MOSFET structure alleviates the problem of short channel effects (SCEs) and the drain induced barrier lowering (DIBL) more efficiently. The proposed model is verified by comparing the theoretical results with the simulated data obtained by using the commercially available ATLASTM 2D device simulator.展开更多
The traditional geometrical depolarization model that single transmitter to single receiver provides a simple method of polarization channel modeling. It can obtain the geometrical depolarization effect of each path i...The traditional geometrical depolarization model that single transmitter to single receiver provides a simple method of polarization channel modeling. It can obtain the geometrical depolarization effect of each path if known the antenna configuration, the polarization field radiation pattern and the spatial distribution of scatters. With the development of communication technology, information transmission spectrum is more and more scarce. The original model provides only a single channel polarization state, so the information will be limited that the polarization state carries in the polarization modulation. The research is so significance that how to carries polarization modulation information by using multi-antenna polarization state. However, the present study shows that have no depolarization effect model for multi-antenna systems. In this paper, we propose a multi-antenna geometrical depolarization model. On the basis of a single antenna to calculate the depolarization effect of the model, and through simulation to analysis the main factors that influence the depolarization effect. This article provides a multi-antenna geometrical depolarization channel modeling that can applied to large-scale array antenna, and to some extent increase the speed of information transmission.展开更多
Total ionizing dose responses of different transistor geometries after being irradiated by ^(60)Co γ-rays, in 0.13-μm partially-depleted silicon-on-insulator(PD SOI) technology are investigated. The negative thr...Total ionizing dose responses of different transistor geometries after being irradiated by ^(60)Co γ-rays, in 0.13-μm partially-depleted silicon-on-insulator(PD SOI) technology are investigated. The negative threshold voltage shift in an n-type metal-oxide semiconductor field effect transistor(nMOSFET) is inversely proportional to the channel width due to radiation-induced charges trapped in trench oxide, which is called the radiation-induced narrow channel effect(RINCE).The analysis based on a charge sharing model and three-dimensional technology computer aided design(TCAD) simulations demonstrate that phenomenon. The radiation-induced leakage currents under different drain biases are also discussed in detail.展开更多
The modified powdery mixture of ammonium nitrate and fuel oil (MPANFO) is a new breed of industrial explosives developed years ago in China. As one of the important properties of an industrial explosive, the channel...The modified powdery mixture of ammonium nitrate and fuel oil (MPANFO) is a new breed of industrial explosives developed years ago in China. As one of the important properties of an industrial explosive, the channel effect of MPANFO was reported in this paper. A series of experiments were conducted to determine the channel effect of MPANFO. The blasthole diameter range was estimated to avoid the channel effect of MPANFO. Three empirical formulae for predicting the detonation length of MPANFO were provided in terms of the channel effect. Experiments and theoretical analysis indicate that the channel effect of MPANFO is very serious. The reason why the channel effect of MPANFO is worse than that of other industrial explosives is explained at a theoretical level. In addition, some properties of MPANFO, such as sympathetic distance, detonation velocity and brisance, are determined.展开更多
This manuscript explores the behavior of a junctionless tri-gate FinFET at the nano-scale region using SiGe material for the channel.For the analysis,three different channel structures are used:(a)tri-layer stack chan...This manuscript explores the behavior of a junctionless tri-gate FinFET at the nano-scale region using SiGe material for the channel.For the analysis,three different channel structures are used:(a)tri-layer stack channel(TLSC)(Si-SiGe-Si),(b)double layer stack channel(DLSC)(SiGe-Si),(c)single layer channel(SLC)(S_(i)).The I−V characteristics,subthreshold swing(SS),drain-induced barrier lowering(DIBL),threshold voltage(V_(t)),drain current(ION),OFF current(IOFF),and ON-OFF current ratio(ION/IOFF)are observed for the structures at a 20 nm gate length.It is seen that TLSC provides 21.3%and 14.3%more ON current than DLSC and SLC,respectively.The paper also explores the analog and RF factors such as input transconductance(g_(m)),output transconductance(gds),gain(gm/gds),transconductance generation factor(TGF),cut-off frequency(f_(T)),maximum oscillation frequency(f_(max)),gain frequency product(GFP)and linearity performance parameters such as second and third-order harmonics(g_(m2),g_(m3)),voltage intercept points(VIP_(2),VIP_(3))and 1-dB compression points for the three structures.The results show that the TLSC has a high analog performance due to more gm and provides 16.3%,48.4%more gain than SLC and DLSC,respectively and it also provides better linearity.All the results are obtained using the VisualTCAD tool.展开更多
In the present work, a two-dimensional(2D) analytical framework of triple material symmetrical gate stack(TMGS)DG-MOSFET is presented in order to subdue the short channel effects. A lightly doped channel along wit...In the present work, a two-dimensional(2D) analytical framework of triple material symmetrical gate stack(TMGS)DG-MOSFET is presented in order to subdue the short channel effects. A lightly doped channel along with triple material gate having different work functions and symmetrical gate stack structure, showcases substantial betterment in quashing short channel effects to a good extent. The device functioning amends in terms of improved exemption to threshold voltage roll-off, thereby suppressing the short channel effects. The encroachments of respective device arguments on the threshold voltage of the proposed structure are examined in detail. The significant outcomes are compared with the numerical simulation data obtained by using 2D ATLAS;device simulator to affirm and formalize the proposed device structure.展开更多
The bias dependence of radiation-induced narrow-width channel effects(RINCEs)in 65-nm n-type metal-oxidesemiconductor field-effect transistors(NMOSFETs)is investigated.The threshold voltage of the narrow-width65 nm NM...The bias dependence of radiation-induced narrow-width channel effects(RINCEs)in 65-nm n-type metal-oxidesemiconductor field-effect transistors(NMOSFETs)is investigated.The threshold voltage of the narrow-width65 nm NMOSFET is negatively shifted by total ionizing dose irradiation,due to the RINCE.The experimental results show that the 65 nm narrow-channel NMOSFET has a larger threshold shift when the gate terminal is kept in the ground,which is contrary to the conclusion obtained in the old generation devices.Depending on the three-dimensional simulation,we conclude that electric field distribution alteration caused by shallow trench isolation scaling is responsible for the anomalous RINCE bias dependence in 65 nm technology.展开更多
Besides the common short-channel effect(SCE)of threshold voltage(V_(th))roll-off during the channel length(L)downscaling of In GaZnO(IGZO)thin-film transistors(TFTs),an opposite V_(th)roll-up was reported in this work...Besides the common short-channel effect(SCE)of threshold voltage(V_(th))roll-off during the channel length(L)downscaling of In GaZnO(IGZO)thin-film transistors(TFTs),an opposite V_(th)roll-up was reported in this work.Both roll-off and roll-up effects of Vth were comparatively investigated on IGZO transistors with varied gate insulator(GI),source/drain(S/D),and device architecture.For IGZO transistors with thinner GI,the SCE was attenuated due to the enhanced gate controllability over the variation of channel carrier concentration,while the Vth roll-up became more noteworthy.The latter was found to depend on the relative ratio of S/D series resistance(R_(SD))over channel resistance(R_(CH)),as verified on transistors with different S/D.Thus,an ideal S/D engineering with small R_(SD)but weak dopant diffusion is highly expected during the downscaling of L and GI in IGZO transistors.展开更多
The relentless down-scaling of electronics grands the modern integrated circuits(ICs)with the high speed,low power dissipation and low cost,fulfilling diverse demands of modern life.Whereas,with the semiconductor indu...The relentless down-scaling of electronics grands the modern integrated circuits(ICs)with the high speed,low power dissipation and low cost,fulfilling diverse demands of modern life.Whereas,with the semiconductor industry entering into sub-10 nm technology nodes,degrading device performance and increasing power consumption give rise to insurmountable roadblocks confronted by modern ICs that need to be conquered to sustain the Moore law's life.Bulk semiconductors like prevalent Si are plagued by seriously degraded carrier mobility as thickness thinning down to sub-5 nm,which is imperative to maintain sufficient gate electrostatic controllability to combat the increasingly degraded short channel effects.Nowadays,the emergence of two-dimensional(2D)materials opens up new gateway to eschew the hurdles laid in front of the scaling trend of modern IC,mainly ascribed to their ultimately atomic thickness,capability to maintain carrier mobility with thickness thinning down,dangling-bonds free surface,wide bandgaps tunability and feasibility to constitute diverse heterostructures.Blossoming breakthroughs in discrete electronic device,such as contact engineering,dielectric integration and vigorous channel-length scaling,or large circuits arrays,as boosted yields,improved variations and full-functioned processor fabrication,based on 2D materials have been achieved nowadays,facilitating 2D materials to step under the spotlight of IC industry to be treated as the most potential future successor or complementary counterpart of incumbent Si to further sustain the down-scaling of modern IC.展开更多
An SOI MOSFET with FINFET structure is simulated using a 3 D simulator. I V characteristics and sub threshold characteristics,as well as the short channel effect(SCE) are carefully investigated.SCE can be well c...An SOI MOSFET with FINFET structure is simulated using a 3 D simulator. I V characteristics and sub threshold characteristics,as well as the short channel effect(SCE) are carefully investigated.SCE can be well controlled by reducing fin height.Good performance can be achieved with thin height,so fin height is considered as a key parameter in device design.Simulation results show that FINFETs present performance superior to conventional single gate devices.展开更多
Based on the exact resultant solution of two-dimensional Poisson's equation in strained Si and Si1-xCex layer, a simple and accurate two-dimensional.analytical model including surface channel potential, surface chann...Based on the exact resultant solution of two-dimensional Poisson's equation in strained Si and Si1-xCex layer, a simple and accurate two-dimensional.analytical model including surface channel potential, surface channel electric field, threshold voltage and subthreshold swing for fully depleted gate stack strained Si on silicon-germanium-on-insulator (SGOI) MOSFETs has been developed. The results show that this novel structure can suppress the short channel effects (SCE), the drain-induced barrier-lowering (DIBL) and improve the subthreshold performance in nanoelectronics application. The model is verified by numerical simulation. The model provides the basic designing guidance of gate stack strained Si on SGOI MOSFETs.展开更多
Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs...Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2)) is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2) interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling.展开更多
Based on the exact resultant solution of two-dimensional Poisson's equation, the novel two-dimensional models, which include surface potential, threshold voltage, subthreshold current and subthreshold swing, have bee...Based on the exact resultant solution of two-dimensional Poisson's equation, the novel two-dimensional models, which include surface potential, threshold voltage, subthreshold current and subthreshold swing, have been developed for gate stack symmetrical double-gate strained-Si MOSFETs. The models are verified by numerical simulation. Besides offering the physical insight into device physics, the model provides the basic designing guidance of further immunity of short channel effect of complementary metal-oxide-semiconductor (CMOS)-based device in a nanoscale regime.展开更多
We propose a scaling theory for single gate Al In Sb/In Sb high electron mobility transistors(HEMTs) by solving the two-dimensional(2D) Poisson equation. In our model, the effective conductive path effect(ECPE) ...We propose a scaling theory for single gate Al In Sb/In Sb high electron mobility transistors(HEMTs) by solving the two-dimensional(2D) Poisson equation. In our model, the effective conductive path effect(ECPE) is taken into account to overcome the problems arising from the device scaling. The potential in the effective conducting path is developed and a simple scaling equation is derived. This equation is solved to obtain the minimum channel potential Φdeff,minand the new scaling factor α to model the subthreshold behavior of the HEMTs. The developed model minimizes the leakage current and improves the subthreshold swing degradation of the HEMTs. The results of the analytical model are verified by numerical simulation with a Sentaurus TCAD device simulator.展开更多
In order to study the permeability and water-resisting ability of the strata on the top of the Ordovician in Longgu Coal Mine, this paper tested the permeability and porosity of the strata, investigated the fracture a...In order to study the permeability and water-resisting ability of the strata on the top of the Ordovician in Longgu Coal Mine, this paper tested the permeability and porosity of the strata, investigated the fracture and pore structure features of the strata, and identified the main channels which govern the permeability and water-resisting ability of the strata. The permeability of the upper, central and lower strata shows as 2.0504 × 10^-3-2.782762× 10^-3, 4.1092 × 10^-3 -7.3387 × 10^-3 and 2.0891 ×10^-3-3.2705 × 10-3 μm^2, respectively, and porosity of that is 0.6786-0.9197%, 0.3109-0.3951% and 0.9829-1.8655%, respectively. The results indicate that: (I) the main channels of the relative water-resisting layer are the pore throats with a diameter more than 6 μm; (2) the major proportion of pore throats in the vertical flow channel and the permeability first increases and then sharply decreases; (3) the fractures occurring from the top to 20 m in depth of the strata were filled and there occurred almost no fracture under the depth of 40 m; and (4) the ratio of turning point of the main flow channel in the strata on top of Ordovician can be used to confirm the thickness of filled water-resisting lavers.展开更多
By performing a molecular dynamics simulation, fragmentation of Cu_n clusters scattering from a single-crystal Cu(111) surface is studied. The interactions among copper atoms are modeled by tight-binding potential, ...By performing a molecular dynamics simulation, fragmentation of Cu_n clusters scattering from a single-crystal Cu(111) surface is studied. The interactions among copper atoms are modeled by tight-binding potential, and the positions of the copper clusters at each time step are calculated by integrating the Newton equations of motion. The percentage of unfragmented clusters depends on the incident velocities, angles of incidence, and surface structure. The influence of surface structure on the fragment distribution is discussed, and the clusters appear to be more stable under an axial channeling condition. The fragment distribution shifting toward the small fragment range for cluster scattering along a random direction is confirmed, indicating that the cluster undergoes more intensive fragmentation.展开更多
High-Speed Rail(HSR)has increasingly become an important mode of inter-city transportation between large cities.Inter-city interaction facilitated by HSR tends to play a more prominent role in promoting urban and regi...High-Speed Rail(HSR)has increasingly become an important mode of inter-city transportation between large cities.Inter-city interaction facilitated by HSR tends to play a more prominent role in promoting urban and regional economic integration and development.Quantifying the impact of HSR’s interaction on cities and people is therefore crucial for long-term urban and regional development planning and policy making.We develop an evaluation framework using toponym information from social media as a proxy to estimate the dynamics of such impact.This paper adopts two types of spatial information:toponyms from social media posts,and the geographical location information embedded in social media posts.The framework highlights the asymmetric nature of social interaction among cities,and proposes a series of metrics to quantify such impact from multiple perspectives-including interaction strength,spatial decay,and channel effect.The results show that HSRs not only greatly expand the uneven distribution of inter-city connections,but also significantly reshape the interactions that occur along HSR routes through the channel effect.展开更多
We preform a first-principles study of performance of 5 nm double-gated(DG)Schottky-barrier field effect transistors(SBFETs)based on two-dimensional SiC with monolayer or bilayer metallic 1T-phase MoS_(2) contacts.Bec...We preform a first-principles study of performance of 5 nm double-gated(DG)Schottky-barrier field effect transistors(SBFETs)based on two-dimensional SiC with monolayer or bilayer metallic 1T-phase MoS_(2) contacts.Because of the wide bandgap of SiC,the corresponding DG SBFETs can weaken the short channel effect.The calculated transfer characteristics also meet the standard of the high performance transistor summarized by international technology road-map for semiconductors.Moreover,the bilayer metallic 1T-phase MoS_(2) contacts in three stacking structures all can further raise the ON-state currents of DG SiC SBFETs in varying degrees.The above results are helpful and instructive for design of short channel transistors in the future.展开更多
文摘This article describes the effective channel length degradation under hot carrier stressing. The extraction is based on the IDs-Vcs characteristics by maximum transconductance (maximum slope of IDs & VGS) in the linear region. The transconductance characteristics are determine for the several devices of difference drawn channel length. The effective channel length of submicron LDD (Lightly Doped Drain) NMOSFETs (Metal Oxide Semiconductor Field Effect Transistor) under hot carrier stressing was measured at the stress time varying from zero to 10,000 seconds. It is shown that the effective channel length was increased with time. This is caused by charges trapping in the oxide during stress. The increased of effective channel length (△Leff) is seem to be increased sharply as the gate channel length is decrease.
文摘GeSi source/drain structure is purposefully adopted in SOI p MOSFET's to suppress the short channel effect (SCE).The impact of GeSi material (as source only,drain only or both source and drain) on the threshold voltage rolling off and DIBL effect is thoroughly investigated,as well as the influence of the Ge concentration and silicon film thickness.The Ge concentration should be carefully chosen as a tradeoff between the driving current and SCE improvement.The detailed physics is explained.
文摘An analytical model for the channel potential and the threshold voltage of the short channel dual-material-gate lightly doped drain (DMG-LDD) metal-oxide-semiconductor field-effect transistor (MOSFET) is presented using the parabolic approximation method. The proposed model takes into account the effects of the LDD region length, the LDD region doping, the lengths of the gate materials and their respective work functions, along with all the major geometrical parameters of the MOSFET. The impact of the LDD region length, the LDD region doping, and the channel length on the channel potential is studied in detail. Furthermore, the threshold voltage of the device is calculated using the minimum middle channel potential, and the result obtained is compared with the DMG MOSFET threshold voltage to show the improvement in the threshold voltage roll-off. It is shown that the DMG-LDD MOSFET structure alleviates the problem of short channel effects (SCEs) and the drain induced barrier lowering (DIBL) more efficiently. The proposed model is verified by comparing the theoretical results with the simulated data obtained by using the commercially available ATLASTM 2D device simulator.
基金supported in part by the National Natural Science Foundation of China(61561039,61461044)the Natural Science Foundation of Ningxia(NZ14045)the Higher School Science and Technology Research Project of Ningxia(NGY2014051)
文摘The traditional geometrical depolarization model that single transmitter to single receiver provides a simple method of polarization channel modeling. It can obtain the geometrical depolarization effect of each path if known the antenna configuration, the polarization field radiation pattern and the spatial distribution of scatters. With the development of communication technology, information transmission spectrum is more and more scarce. The original model provides only a single channel polarization state, so the information will be limited that the polarization state carries in the polarization modulation. The research is so significance that how to carries polarization modulation information by using multi-antenna polarization state. However, the present study shows that have no depolarization effect model for multi-antenna systems. In this paper, we propose a multi-antenna geometrical depolarization model. On the basis of a single antenna to calculate the depolarization effect of the model, and through simulation to analysis the main factors that influence the depolarization effect. This article provides a multi-antenna geometrical depolarization channel modeling that can applied to large-scale array antenna, and to some extent increase the speed of information transmission.
基金Project supported by the Weapon Equipment Pre-Research Foundation of China(Grant No.9140A11020114ZK34147)the Shanghai Municipal Natural Science Foundation,China(Grant No.15ZR1447100)
文摘Total ionizing dose responses of different transistor geometries after being irradiated by ^(60)Co γ-rays, in 0.13-μm partially-depleted silicon-on-insulator(PD SOI) technology are investigated. The negative threshold voltage shift in an n-type metal-oxide semiconductor field effect transistor(nMOSFET) is inversely proportional to the channel width due to radiation-induced charges trapped in trench oxide, which is called the radiation-induced narrow channel effect(RINCE).The analysis based on a charge sharing model and three-dimensional technology computer aided design(TCAD) simulations demonstrate that phenomenon. The radiation-induced leakage currents under different drain biases are also discussed in detail.
基金supported by the National Natural Science Foundation of China (No.50704005)
文摘The modified powdery mixture of ammonium nitrate and fuel oil (MPANFO) is a new breed of industrial explosives developed years ago in China. As one of the important properties of an industrial explosive, the channel effect of MPANFO was reported in this paper. A series of experiments were conducted to determine the channel effect of MPANFO. The blasthole diameter range was estimated to avoid the channel effect of MPANFO. Three empirical formulae for predicting the detonation length of MPANFO were provided in terms of the channel effect. Experiments and theoretical analysis indicate that the channel effect of MPANFO is very serious. The reason why the channel effect of MPANFO is worse than that of other industrial explosives is explained at a theoretical level. In addition, some properties of MPANFO, such as sympathetic distance, detonation velocity and brisance, are determined.
文摘This manuscript explores the behavior of a junctionless tri-gate FinFET at the nano-scale region using SiGe material for the channel.For the analysis,three different channel structures are used:(a)tri-layer stack channel(TLSC)(Si-SiGe-Si),(b)double layer stack channel(DLSC)(SiGe-Si),(c)single layer channel(SLC)(S_(i)).The I−V characteristics,subthreshold swing(SS),drain-induced barrier lowering(DIBL),threshold voltage(V_(t)),drain current(ION),OFF current(IOFF),and ON-OFF current ratio(ION/IOFF)are observed for the structures at a 20 nm gate length.It is seen that TLSC provides 21.3%and 14.3%more ON current than DLSC and SLC,respectively.The paper also explores the analog and RF factors such as input transconductance(g_(m)),output transconductance(gds),gain(gm/gds),transconductance generation factor(TGF),cut-off frequency(f_(T)),maximum oscillation frequency(f_(max)),gain frequency product(GFP)and linearity performance parameters such as second and third-order harmonics(g_(m2),g_(m3)),voltage intercept points(VIP_(2),VIP_(3))and 1-dB compression points for the three structures.The results show that the TLSC has a high analog performance due to more gm and provides 16.3%,48.4%more gain than SLC and DLSC,respectively and it also provides better linearity.All the results are obtained using the VisualTCAD tool.
文摘In the present work, a two-dimensional(2D) analytical framework of triple material symmetrical gate stack(TMGS)DG-MOSFET is presented in order to subdue the short channel effects. A lightly doped channel along with triple material gate having different work functions and symmetrical gate stack structure, showcases substantial betterment in quashing short channel effects to a good extent. The device functioning amends in terms of improved exemption to threshold voltage roll-off, thereby suppressing the short channel effects. The encroachments of respective device arguments on the threshold voltage of the proposed structure are examined in detail. The significant outcomes are compared with the numerical simulation data obtained by using 2D ATLAS;device simulator to affirm and formalize the proposed device structure.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11605282,11505282 and U1532261the West Light Foundation of the Chinese Academy of Sciences under Grant No 2015-XBQN-B-15
文摘The bias dependence of radiation-induced narrow-width channel effects(RINCEs)in 65-nm n-type metal-oxidesemiconductor field-effect transistors(NMOSFETs)is investigated.The threshold voltage of the narrow-width65 nm NMOSFET is negatively shifted by total ionizing dose irradiation,due to the RINCE.The experimental results show that the 65 nm narrow-channel NMOSFET has a larger threshold shift when the gate terminal is kept in the ground,which is contrary to the conclusion obtained in the old generation devices.Depending on the three-dimensional simulation,we conclude that electric field distribution alteration caused by shallow trench isolation scaling is responsible for the anomalous RINCE bias dependence in 65 nm technology.
基金supported financially by National key Research and Development Program under Grant 2021YFB3600802Shenzhen Municipal Scientific Program under Grant KJZD20230923114111021。
文摘Besides the common short-channel effect(SCE)of threshold voltage(V_(th))roll-off during the channel length(L)downscaling of In GaZnO(IGZO)thin-film transistors(TFTs),an opposite V_(th)roll-up was reported in this work.Both roll-off and roll-up effects of Vth were comparatively investigated on IGZO transistors with varied gate insulator(GI),source/drain(S/D),and device architecture.For IGZO transistors with thinner GI,the SCE was attenuated due to the enhanced gate controllability over the variation of channel carrier concentration,while the Vth roll-up became more noteworthy.The latter was found to depend on the relative ratio of S/D series resistance(R_(SD))over channel resistance(R_(CH)),as verified on transistors with different S/D.Thus,an ideal S/D engineering with small R_(SD)but weak dopant diffusion is highly expected during the downscaling of L and GI in IGZO transistors.
基金supported by start-up capital of Ningbo Eastern Institute of technology。
文摘The relentless down-scaling of electronics grands the modern integrated circuits(ICs)with the high speed,low power dissipation and low cost,fulfilling diverse demands of modern life.Whereas,with the semiconductor industry entering into sub-10 nm technology nodes,degrading device performance and increasing power consumption give rise to insurmountable roadblocks confronted by modern ICs that need to be conquered to sustain the Moore law's life.Bulk semiconductors like prevalent Si are plagued by seriously degraded carrier mobility as thickness thinning down to sub-5 nm,which is imperative to maintain sufficient gate electrostatic controllability to combat the increasingly degraded short channel effects.Nowadays,the emergence of two-dimensional(2D)materials opens up new gateway to eschew the hurdles laid in front of the scaling trend of modern IC,mainly ascribed to their ultimately atomic thickness,capability to maintain carrier mobility with thickness thinning down,dangling-bonds free surface,wide bandgaps tunability and feasibility to constitute diverse heterostructures.Blossoming breakthroughs in discrete electronic device,such as contact engineering,dielectric integration and vigorous channel-length scaling,or large circuits arrays,as boosted yields,improved variations and full-functioned processor fabrication,based on 2D materials have been achieved nowadays,facilitating 2D materials to step under the spotlight of IC industry to be treated as the most potential future successor or complementary counterpart of incumbent Si to further sustain the down-scaling of modern IC.
文摘An SOI MOSFET with FINFET structure is simulated using a 3 D simulator. I V characteristics and sub threshold characteristics,as well as the short channel effect(SCE) are carefully investigated.SCE can be well controlled by reducing fin height.Good performance can be achieved with thin height,so fin height is considered as a key parameter in device design.Simulation results show that FINFETs present performance superior to conventional single gate devices.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60976068 and 60936005)the Cultivation Fund of the Key Scientific and Technical Innovation Project, Ministry of Education of China (Grant No. 708083)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 200807010010)
文摘Based on the exact resultant solution of two-dimensional Poisson's equation in strained Si and Si1-xCex layer, a simple and accurate two-dimensional.analytical model including surface channel potential, surface channel electric field, threshold voltage and subthreshold swing for fully depleted gate stack strained Si on silicon-germanium-on-insulator (SGOI) MOSFETs has been developed. The results show that this novel structure can suppress the short channel effects (SCE), the drain-induced barrier-lowering (DIBL) and improve the subthreshold performance in nanoelectronics application. The model is verified by numerical simulation. The model provides the basic designing guidance of gate stack strained Si on SGOI MOSFETs.
文摘Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2)) is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2) interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60976068 and 60936005)Cultivation Fund of the Key Scientific and Technical Innovation Project, Ministry of Education of China (Grant No. 708083),Cultivation Fund of the Key Scientific and Technical Innovation Project, Ministry of Education of China (Grant No. 200807010010)
文摘Based on the exact resultant solution of two-dimensional Poisson's equation, the novel two-dimensional models, which include surface potential, threshold voltage, subthreshold current and subthreshold swing, have been developed for gate stack symmetrical double-gate strained-Si MOSFETs. The models are verified by numerical simulation. Besides offering the physical insight into device physics, the model provides the basic designing guidance of further immunity of short channel effect of complementary metal-oxide-semiconductor (CMOS)-based device in a nanoscale regime.
基金Project supported by the Council of Scientific&Industrial Research(CSIR),Government of India under the SRF Scheme(Sanction Letter No:08/237(0005)/2012-EMR-I)
文摘We propose a scaling theory for single gate Al In Sb/In Sb high electron mobility transistors(HEMTs) by solving the two-dimensional(2D) Poisson equation. In our model, the effective conductive path effect(ECPE) is taken into account to overcome the problems arising from the device scaling. The potential in the effective conducting path is developed and a simple scaling equation is derived. This equation is solved to obtain the minimum channel potential Φdeff,minand the new scaling factor α to model the subthreshold behavior of the HEMTs. The developed model minimizes the leakage current and improves the subthreshold swing degradation of the HEMTs. The results of the analytical model are verified by numerical simulation with a Sentaurus TCAD device simulator.
基金Financial supports for this work provided by the National Basic Research Program of China(2013CB227900)the Innovation of Graduate Student Training Project in Jiangsu Province of China(CXZZ13_0934)
文摘In order to study the permeability and water-resisting ability of the strata on the top of the Ordovician in Longgu Coal Mine, this paper tested the permeability and porosity of the strata, investigated the fracture and pore structure features of the strata, and identified the main channels which govern the permeability and water-resisting ability of the strata. The permeability of the upper, central and lower strata shows as 2.0504 × 10^-3-2.782762× 10^-3, 4.1092 × 10^-3 -7.3387 × 10^-3 and 2.0891 ×10^-3-3.2705 × 10-3 μm^2, respectively, and porosity of that is 0.6786-0.9197%, 0.3109-0.3951% and 0.9829-1.8655%, respectively. The results indicate that: (I) the main channels of the relative water-resisting layer are the pore throats with a diameter more than 6 μm; (2) the major proportion of pore throats in the vertical flow channel and the permeability first increases and then sharply decreases; (3) the fractures occurring from the top to 20 m in depth of the strata were filled and there occurred almost no fracture under the depth of 40 m; and (4) the ratio of turning point of the main flow channel in the strata on top of Ordovician can be used to confirm the thickness of filled water-resisting lavers.
基金Project supported by the National Natural Science Foundation of China(Grant No.11405166)
文摘By performing a molecular dynamics simulation, fragmentation of Cu_n clusters scattering from a single-crystal Cu(111) surface is studied. The interactions among copper atoms are modeled by tight-binding potential, and the positions of the copper clusters at each time step are calculated by integrating the Newton equations of motion. The percentage of unfragmented clusters depends on the incident velocities, angles of incidence, and surface structure. The influence of surface structure on the fragment distribution is discussed, and the clusters appear to be more stable under an axial channeling condition. The fragment distribution shifting toward the small fragment range for cluster scattering along a random direction is confirmed, indicating that the cluster undergoes more intensive fragmentation.
基金This work is supported by the National Natural Science Foundation of China[grant numbers 41801378,42071382].
文摘High-Speed Rail(HSR)has increasingly become an important mode of inter-city transportation between large cities.Inter-city interaction facilitated by HSR tends to play a more prominent role in promoting urban and regional economic integration and development.Quantifying the impact of HSR’s interaction on cities and people is therefore crucial for long-term urban and regional development planning and policy making.We develop an evaluation framework using toponym information from social media as a proxy to estimate the dynamics of such impact.This paper adopts two types of spatial information:toponyms from social media posts,and the geographical location information embedded in social media posts.The framework highlights the asymmetric nature of social interaction among cities,and proposes a series of metrics to quantify such impact from multiple perspectives-including interaction strength,spatial decay,and channel effect.The results show that HSRs not only greatly expand the uneven distribution of inter-city connections,but also significantly reshape the interactions that occur along HSR routes through the channel effect.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12074046 and 12074115)the Hunan Provincial Natural Science Foundation of China(Grant Nos.2020JJ4597,2021JJ40558,and 2021JJ30733)+1 种基金the Scientific Research Fund of Hunan Provincial Education Department,China(Grant Nos.20K007 and 20C0039)the Key Projects of Changsha Science and Technology Plan(Grant No.kq1901102).
文摘We preform a first-principles study of performance of 5 nm double-gated(DG)Schottky-barrier field effect transistors(SBFETs)based on two-dimensional SiC with monolayer or bilayer metallic 1T-phase MoS_(2) contacts.Because of the wide bandgap of SiC,the corresponding DG SBFETs can weaken the short channel effect.The calculated transfer characteristics also meet the standard of the high performance transistor summarized by international technology road-map for semiconductors.Moreover,the bilayer metallic 1T-phase MoS_(2) contacts in three stacking structures all can further raise the ON-state currents of DG SiC SBFETs in varying degrees.The above results are helpful and instructive for design of short channel transistors in the future.