A robust spontaneous exchange bias effect after zero-field cooling was observed in Co_(2)Sn_(1-x)Cr_(x)O_(4)system,which was driven by the transition from superspin-glass to superferromagnetic domain embedded in the f...A robust spontaneous exchange bias effect after zero-field cooling was observed in Co_(2)Sn_(1-x)Cr_(x)O_(4)system,which was driven by the transition from superspin-glass to superferromagnetic domain embedded in the ferrimagnetic matrix.Additionally,the exchange bias effect is gradually pronounced with the positive increase in the cooling field,known as the conventional exchange bias effect.However,as the cooling field gradually decreases and transits from positive to negative,the exchange bias effect can robustly remain positive in the low-negative-field region until the cooling field increases to be sufficiently large in the negative direction.展开更多
A non-depletion floating layer silicon-on-insulator （NFL SOI） lateral double-diffused metal–oxide–semiconductor （LDMOS） is proposed and the NFL-assisted modulated field （NFLAMF） principle is investigated in th...A non-depletion floating layer silicon-on-insulator （NFL SOI） lateral double-diffused metal–oxide–semiconductor （LDMOS） is proposed and the NFL-assisted modulated field （NFLAMF） principle is investigated in this paper. Based on this principle, the floating layer can pin the potential for modulating bulk field. In particular, the accumulated high concentration of holes at the bottom of the NFL can efficiently shield the electric field of the SOI layer and enhance the dielectric field in the buried oxide layer （BOX）. At variation of back-gate bias, the shielding charges of NFL can also eliminate back-gate effects. The simulated results indicate that the breakdown voltage （BV） is increased from 315 V to 558 V compared to the conventional reduced surface field （RESURF） SOI （CSOI） LDMOS, yielding a 77% improvement. Furthermore, due to the field shielding effect of the NFL, the device can maintain the same breakdown voltage of 558 V with a thinner BOX to resolve the thermal problem in an SOI device.展开更多
An analytical expression for the co/lector resistance of a novel vertical SiGe heterojunction bipolar transistor （HBT） on thin film silicon-on-insulator （SOI） is obtained with the substrate bias effects being cons...An analytical expression for the co/lector resistance of a novel vertical SiGe heterojunction bipolar transistor （HBT） on thin film silicon-on-insulator （SOI） is obtained with the substrate bias effects being considered. The resistance is found to decrease slowly and then quickly and to have kinks with the increase of the substrate-collector bias, which is quite different from that of a conventional bulk HBT. The model is consistent with the simulation result and the reported data and is useful to the frequency characteristic design of 0.13 μtm millimeter-wave SiGe SOI BiCMOS devices.展开更多
The effect of the positive bias on Reynolds stress （RS） and its effect on the radial turbulent transport at the edge plasma （r/a =0.9） and scrape-off layer （SOL） region of plasma in tokamak are investigated. The...The effect of the positive bias on Reynolds stress （RS） and its effect on the radial turbulent transport at the edge plasma （r/a =0.9） and scrape-off layer （SOL） region of plasma in tokamak are investigated. The radial and poloidal electric fields （Sr, Ep） and ion saturation current （Is） are measured by multi-purpose probe （MPP）. This probe is fabricated and constructed for the first time in the IR-T1 tokamak. The most advantage of this probe is that the variations of Er and Ep can be measured in different radii at the single shot. Thus the information of different radii can be compared with high precision. The bias voltage is fixed at Vbias = 200 V and it has been applied with the limiter bias that is fixed in r/a = 0.9. Moreover, the phase difference between radial and poloidal electric fields, and temporal evolution of the RS .spectrum detected by MPP are calculated. RS magnitude on the edge （r/a = 0.9） is more than its value in the SOL （r/a = 1.02）. With the applied bias 200 V, ItS and the magnitude of the phase difference between Er and Ep are increased, while the radial turbulent transport is decreased simultaneously. Thus it can be concluded that RS affects radial turbulence. Temporal evolution of the RS spectrum shows that the frequency of RS is increased and reaches its highest value at r/a=0.9 in the presence of bias.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
Based on first-principles calculations,the bias-induced evolutions of hybrid interface states inπ-conjugated tricene and in insulating octane magnetic molecular junctions are investigated.Obvious bias-induced splitti...Based on first-principles calculations,the bias-induced evolutions of hybrid interface states inπ-conjugated tricene and in insulating octane magnetic molecular junctions are investigated.Obvious bias-induced splitting and energy shift of the spin-resolved hybrid interface states are observed in the two junctions.The recombination of the shifted hybrid interface states from different interfaces makes the spin polarization around the Fermi energy strongly bias-dependent.The transport calculations demonstrate that in theπ-conjugated tricene junction,the bias-dependent hybrid interface states work efficiently for large current,current spin polarization,and distinct tunneling magnetoresistance.But in the insulating octane junction,the spin-dependent transport via the hybrid interface states is inhibited,which is only slightly disturbed by the bias.This work reveals the phenomenon of bias-induced reconstruction of hybrid interface states in molecular spinterface devices,and the underlying role of conjugated molecular orbitals in the transport ability of hybrid interface states.展开更多
In this paper, we investigate the performance of the bulk fin field effect transistor （FinFET） through a three- dimensional （3D） full band Monte Carlo simulator with quantum correction. Several scattering mechanis...In this paper, we investigate the performance of the bulk fin field effect transistor （FinFET） through a three- dimensional （3D） full band Monte Carlo simulator with quantum correction. Several scattering mechanisms, such as the acoustic and optical phonon scattering, the ionized impurity scattering, the impact ionization scattering and the surface roughness scattering are considered in our simulator. The effects of the substrate bias and the surface roughness scattering near the Si/SiO2 interface on the performance of bulk FinFET are mainly discussed in our work. Our results show that the on-current of bulk FinFET is sensitive to the surface roughness and that we can reduce the substrate leakage current by modulating the substrate bias voltage.展开更多
High-entropy alloys(HEAs)have attracted extensive attention ascribed to their unique physical and chemical properties induced by the cocktail effect.However,their oxidation behaviors,in particular at nanoscale,are sti...High-entropy alloys(HEAs)have attracted extensive attention ascribed to their unique physical and chemical properties induced by the cocktail effect.However,their oxidation behaviors,in particular at nanoscale,are still lack because of multi-element complexity,which could also be completely differ-ent from the bulk counterparts.In this work,we synthesized FeCoNiTiCu five-element HEA nanopar-ticles(NPs)with uniform elemental distribution by arc-discharging approach,and further investigated their oxidation behaviors at 250 ℃,and 350 ℃.The morphology,structure and element distribution of NPs were analyzed by transmission electron microscopy(TEM),energy dispersive spectroscopy(EDS)and electron energy loss spectroscopy(EELS).The surface oxidation in FeCoNiTiCu NPs during the high-temperature process can induce nanoscale pores at core/shell interfaces by Kirkendall effect,and even the eventual coalescence into a single cavity.Additionally,the oxidation states of NPs with diameters(d)varying from 60 to 350 nm were analyzed in detail,revealing two typical configurations:hollow(d<150 nm)and yolk-shell structures(d>150 nm).The experimental results were complemented by first-principles calculations to investigate the diffusion behaviors of five elements,evidencing that the surface oxidation strongly alters the surface segregation preferences:(1)in the initial stage,Cu and Ni appear to prefer segregating on the surface,while Co,Ti and Fe tend to stay in the bulk;(2)in the oxidation process,Cu prefers to stay in the center,while Ti segregates to the surface ascribed to the reduced po-tential energies.The study gives new insights into oxidation of nanoscale HEA,and also provides a way for fabrication of high-entropy oxides with controllable architectures.展开更多
目的:于乳腺癌患者群体中探讨偏颇体质在焦虑形成抑郁过程中的中介作用。方法:应用自制量表、中医体质量表(constitution in Chinese medicine questionnaire,CCMQ)和医院焦虑抑郁量表(hospital anxiety and depression scale,HADS)对2...目的:于乳腺癌患者群体中探讨偏颇体质在焦虑形成抑郁过程中的中介作用。方法:应用自制量表、中医体质量表(constitution in Chinese medicine questionnaire,CCMQ)和医院焦虑抑郁量表(hospital anxiety and depression scale,HADS)对2019年7月—2021年5月选取于云南省肿瘤医院并符合纳排标准的患者进行基本信息采集、中医体质评价及焦虑抑郁状况评定。在数据标准化的基础上,对所获偏颇体质得分进行主成分分析,再进一步通过Pearson相关分析、多元线性回归模型及Bootstrap法探讨偏颇体质得分的中介作用。结果:回收有效问卷950份,有效回收率90.65%。950例患者中存在焦虑或抑郁的患者共398例,其中283例(71.11%)属于焦虑抑郁共病。8种偏颇体质得分降维后获得一个主成分“偏颇体质得分”,特征值>1,方差贡献率为80.13%。将其纳入Pearson相关分析后得出,偏颇体质得分与焦虑得分、抑郁得分均呈正相关(r=0.688,0.643,P<0.001),焦虑得分与抑郁得分呈正相关(r=0.860,P<0.001)。偏颇体质在焦虑与抑郁发生间起部分中介作用,中介效应量为0.063,总效应量为0.063+0.784=0.847,中介效应占总效应的7.44%。结论:对焦虑患者的偏颇体质进行纠正治疗,可在一定程度上预防抑郁的发生,从而减少乳腺癌患者焦虑抑郁共病的发生率,改善其心理健康及远期预后。展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.11474111 and 11604281)the Young Elite Scientists Sponsorship Program by CAST(No.YESS20220618)the Hundreds of Talents program of Sun Yat-sen University(No.210192)
文摘A robust spontaneous exchange bias effect after zero-field cooling was observed in Co_(2)Sn_(1-x)Cr_(x)O_(4)system,which was driven by the transition from superspin-glass to superferromagnetic domain embedded in the ferrimagnetic matrix.Additionally,the exchange bias effect is gradually pronounced with the positive increase in the cooling field,known as the conventional exchange bias effect.However,as the cooling field gradually decreases and transits from positive to negative,the exchange bias effect can robustly remain positive in the low-negative-field region until the cooling field increases to be sufficiently large in the negative direction.
文摘A non-depletion floating layer silicon-on-insulator （NFL SOI） lateral double-diffused metal–oxide–semiconductor （LDMOS） is proposed and the NFL-assisted modulated field （NFLAMF） principle is investigated in this paper. Based on this principle, the floating layer can pin the potential for modulating bulk field. In particular, the accumulated high concentration of holes at the bottom of the NFL can efficiently shield the electric field of the SOI layer and enhance the dielectric field in the buried oxide layer （BOX）. At variation of back-gate bias, the shielding charges of NFL can also eliminate back-gate effects. The simulated results indicate that the breakdown voltage （BV） is increased from 315 V to 558 V compared to the conventional reduced surface field （RESURF） SOI （CSOI） LDMOS, yielding a 77% improvement. Furthermore, due to the field shielding effect of the NFL, the device can maintain the same breakdown voltage of 558 V with a thinner BOX to resolve the thermal problem in an SOI device.
基金Project supported by National Ministries and Commissions(Grant Nos.51308040203 and 6139801)the Fundamental Research Funds for the Central Universities,China(Grant Nos.72105499 and 72104089)the Natural Science Basic Research Plan in Shaanxi Province of China(Grant No.2010JQ8008)
文摘An analytical expression for the co/lector resistance of a novel vertical SiGe heterojunction bipolar transistor （HBT） on thin film silicon-on-insulator （SOI） is obtained with the substrate bias effects being considered. The resistance is found to decrease slowly and then quickly and to have kinks with the increase of the substrate-collector bias, which is quite different from that of a conventional bulk HBT. The model is consistent with the simulation result and the reported data and is useful to the frequency characteristic design of 0.13 μtm millimeter-wave SiGe SOI BiCMOS devices.
文摘The effect of the positive bias on Reynolds stress （RS） and its effect on the radial turbulent transport at the edge plasma （r/a =0.9） and scrape-off layer （SOL） region of plasma in tokamak are investigated. The radial and poloidal electric fields （Sr, Ep） and ion saturation current （Is） are measured by multi-purpose probe （MPP）. This probe is fabricated and constructed for the first time in the IR-T1 tokamak. The most advantage of this probe is that the variations of Er and Ep can be measured in different radii at the single shot. Thus the information of different radii can be compared with high precision. The bias voltage is fixed at Vbias = 200 V and it has been applied with the limiter bias that is fixed in r/a = 0.9. Moreover, the phase difference between radial and poloidal electric fields, and temporal evolution of the RS .spectrum detected by MPP are calculated. RS magnitude on the edge （r/a = 0.9） is more than its value in the SOL （r/a = 1.02）. With the applied bias 200 V, ItS and the magnitude of the phase difference between Er and Ep are increased, while the radial turbulent transport is decreased simultaneously. Thus it can be concluded that RS affects radial turbulence. Temporal evolution of the RS spectrum shows that the frequency of RS is increased and reaches its highest value at r/a=0.9 in the presence of bias.
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Project supported by the National Natural Science Foundation of China(Grant Nos.11974215,21933002,and 11874242)the Shandong Provincial Natural Science Foundation,China(Grant No.ZR2019MA043)。
文摘Based on first-principles calculations,the bias-induced evolutions of hybrid interface states inπ-conjugated tricene and in insulating octane magnetic molecular junctions are investigated.Obvious bias-induced splitting and energy shift of the spin-resolved hybrid interface states are observed in the two junctions.The recombination of the shifted hybrid interface states from different interfaces makes the spin polarization around the Fermi energy strongly bias-dependent.The transport calculations demonstrate that in theπ-conjugated tricene junction,the bias-dependent hybrid interface states work efficiently for large current,current spin polarization,and distinct tunneling magnetoresistance.But in the insulating octane junction,the spin-dependent transport via the hybrid interface states is inhibited,which is only slightly disturbed by the bias.This work reveals the phenomenon of bias-induced reconstruction of hybrid interface states in molecular spinterface devices,and the underlying role of conjugated molecular orbitals in the transport ability of hybrid interface states.
基金Project supported by the National Basic Research Program of China (Grant No. 2011CBA00604)
文摘In this paper, we investigate the performance of the bulk fin field effect transistor （FinFET） through a three- dimensional （3D） full band Monte Carlo simulator with quantum correction. Several scattering mechanisms, such as the acoustic and optical phonon scattering, the ionized impurity scattering, the impact ionization scattering and the surface roughness scattering are considered in our simulator. The effects of the substrate bias and the surface roughness scattering near the Si/SiO2 interface on the performance of bulk FinFET are mainly discussed in our work. Our results show that the on-current of bulk FinFET is sensitive to the surface roughness and that we can reduce the substrate leakage current by modulating the substrate bias voltage.
基金National Science Fund for Distinguished Young Scholars(No.52225312)Key Research and Development Program of Zhejiang Province(Nos.2021C01033,2023C01077)National Natural Science Foundation of China(No.U1908220).
文摘High-entropy alloys(HEAs)have attracted extensive attention ascribed to their unique physical and chemical properties induced by the cocktail effect.However,their oxidation behaviors,in particular at nanoscale,are still lack because of multi-element complexity,which could also be completely differ-ent from the bulk counterparts.In this work,we synthesized FeCoNiTiCu five-element HEA nanopar-ticles(NPs)with uniform elemental distribution by arc-discharging approach,and further investigated their oxidation behaviors at 250 ℃,and 350 ℃.The morphology,structure and element distribution of NPs were analyzed by transmission electron microscopy(TEM),energy dispersive spectroscopy(EDS)and electron energy loss spectroscopy(EELS).The surface oxidation in FeCoNiTiCu NPs during the high-temperature process can induce nanoscale pores at core/shell interfaces by Kirkendall effect,and even the eventual coalescence into a single cavity.Additionally,the oxidation states of NPs with diameters(d)varying from 60 to 350 nm were analyzed in detail,revealing two typical configurations:hollow(d<150 nm)and yolk-shell structures(d>150 nm).The experimental results were complemented by first-principles calculations to investigate the diffusion behaviors of five elements,evidencing that the surface oxidation strongly alters the surface segregation preferences:(1)in the initial stage,Cu and Ni appear to prefer segregating on the surface,while Co,Ti and Fe tend to stay in the bulk;(2)in the oxidation process,Cu prefers to stay in the center,while Ti segregates to the surface ascribed to the reduced po-tential energies.The study gives new insights into oxidation of nanoscale HEA,and also provides a way for fabrication of high-entropy oxides with controllable architectures.
文摘目的:于乳腺癌患者群体中探讨偏颇体质在焦虑形成抑郁过程中的中介作用。方法:应用自制量表、中医体质量表(constitution in Chinese medicine questionnaire,CCMQ)和医院焦虑抑郁量表(hospital anxiety and depression scale,HADS)对2019年7月—2021年5月选取于云南省肿瘤医院并符合纳排标准的患者进行基本信息采集、中医体质评价及焦虑抑郁状况评定。在数据标准化的基础上,对所获偏颇体质得分进行主成分分析,再进一步通过Pearson相关分析、多元线性回归模型及Bootstrap法探讨偏颇体质得分的中介作用。结果:回收有效问卷950份,有效回收率90.65%。950例患者中存在焦虑或抑郁的患者共398例,其中283例(71.11%)属于焦虑抑郁共病。8种偏颇体质得分降维后获得一个主成分“偏颇体质得分”,特征值>1,方差贡献率为80.13%。将其纳入Pearson相关分析后得出,偏颇体质得分与焦虑得分、抑郁得分均呈正相关(r=0.688,0.643,P<0.001),焦虑得分与抑郁得分呈正相关(r=0.860,P<0.001)。偏颇体质在焦虑与抑郁发生间起部分中介作用,中介效应量为0.063,总效应量为0.063+0.784=0.847,中介效应占总效应的7.44%。结论:对焦虑患者的偏颇体质进行纠正治疗,可在一定程度上预防抑郁的发生,从而减少乳腺癌患者焦虑抑郁共病的发生率,改善其心理健康及远期预后。
