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971.
Evaluation of negative bias temperature instability in ultra-thin gate oxide pMOSFETs using a new on-line PDO method 下载免费PDF全文
A new on-line methodology is used to characterize the negative bias temperature
instability (NBTI) without inherent recovery. Saturation drain voltage shift and
mobility shift are extracted by ID-VD characterizations, which were
measured before stress, and after every certain stress phase, using the
proportional differential operator (PDO) method. The new on-line methodology avoids
the mobility linearity assumption as compared with the previous on-the-fly method.
It is found that both reaction--diffusion and charge-injection processes are
important in NBTI effect under either DC or AC stress. A similar activation energy,
0.15 eV, occurred in both DC and AC NBTI processes. Also degradation rate factor is
independent of temperature below 90\du\ and sharply increases above it. The
frequency dependence of NBTI degradation shows that NBTI degradation is independent
of frequencies. The carrier tunnelling and reaction--diffusion mechanisms exist
simultaneously in NBTI degradation of sub-micron pMOSFETs, and the carrier
tunnelling dominates the earlier NBTI stage and the reaction--diffusion mechanism
follows when the generation rate of traps caused by carrier tunnelling reaches its
maximum. 相似文献
972.
Exotic Behavior of Elastic Scattering Differential Cross-Sections of Weakly Bound Nucleus 17F at Small Angles 下载免费PDF全文
HAN Jian-Long WANG Qi XIAO Zhi-Gang XU Hu-Shan SUN Zhi-Yu HU Zheng-Guo ZHANG Xue-Yin WANG Hong-Wei MAO Rui-Shi YUAN Xiao-Hua XU Zhi-Guo ZHAO Tie-Cheng 《中国物理C(英文版)》2006,30(11):1058-1061
The differential cross-sections for elastic scattering of 17F and 17O on 208Pb have been measured at Radioactive Ion Beam Line at Lanzhou (RIBLL). The variation of the logarithms of differential cross-sections with the square of scattering angles shows clearly that there exists a turning point in the range of small scattering angles (6°—20°) for 17F having exotic structure, while no turning point was observed in the 17O elastic scattering. The experimental results have been compared with previous data. Systematical analysis on the available data seems to conclude that there is an exotic behavior of elastic scattering differential cross-sections of weakly bound nuclei with halo or skin structure as compared with that of the ordinary nuclei near stable line. Therefore the fact that the turning point of the logarithms of differential cross-sections appears at small angle for weakly bound nuclei could be used as a new probe to investigate the halo and skin phenomenon. 相似文献
973.
If all the supersymmetry particles (sparticles) except a light Higgs boson are too heavy to be directly produced at the Large Hadron Collider (LHC), a possible way to reveal evidence for supersymmetry is through their virtual effects in other processes. We examine such supersymmetric QCD effects in bottom pair production associated with a light Higgs boson at the LHC. We find that if the relevant sparticles (gluinos and squarks) are too heavy to be directly produced well above the TeV scale, they can still have sizable virtual effects in this process. For large tanβ, such residual effects can alter the production rate by over 40 percent,which should be observable in future measurements of this process at the LHC. 相似文献
974.
激光诱导沉积银膜制备新型光纤SERS传感器 总被引:1,自引:1,他引:0
利用激光诱导沉积的方法直接在光纤端面沉积了银纳米膜,并用SERS光谱监测了这一沉积过程,在光纤端面上生成的银膜出现了“年轮”状宏观形貌,这种形貌与激光在光纤中的干涉与衍射条纹分布相一致,证明了这种现象是由激光诱导反应引发的. 结合实验结果进一步讨论了银纳米膜的形成机理. 在光纤上沉积的银纳米膜作为光纤SERS传感器的基底与其它制备基底的方法比较也具有实验操作简便,耗时短,重现性好,SERS增强效果强等诸多优点,是一种非常好的制备光纤SERS传感器基底的方法. 相似文献
975.
976.
977.
近红外光谱监测体外循环手术中脑组织氧合状况的研究 总被引:6,自引:3,他引:3
体外循环手术中,为防止因脑氧供需失衡导致脑缺氧,就要实时监测患者局部脑组织的氧合状况,以根据其变化调整生理参数或采取应急手段。用该研究小组自行研制的近红外仪器(使用一个双波长的近红外光源和两个近红外检测器)监测心脏手术中患者的脑氧,可以求出局部脑组织血红蛋白浓度的变化,并根据稳态空间分辨光谱(SRS)算法求出局部脑组织的氧饱和度(rSO2)。体外循环中用监护仪监测患者的混合静脉血氧饱和度(SvO2)等生理参数。测得的血红蛋白浓度变化容易受到干扰,而rSO2的抗干扰性能较好。rSO2在整个手术过程中都可以监测到,而SvO2只能在体外循环过程中监测到。多数患者rSO2和SvO2存在正向相关性,但二者的相关系数并不很高。这是因为SvO2是大静脉的血氧饱和度,而测得的rSO2反映局部脑组织的氧合状况,二者的生理意义不同。实验结果表明,体外循环手术中rSO2可以反映患者脑组织氧合状况的变化,而仅仅监测SvO2是不够的。 相似文献
978.
979.
针对汽车冲撞行人抛出速度问题,利用人体直杆模型,运用有关力学原
理,得出汽车与行人第一次冲撞后人体的转动角速度和平动速度,进而讨论了不同冲撞车速
下人体倒向发动机罩的可能运动状态,结果比较符合实际情况.这对交通事故鉴定工作具有应
用价值. 相似文献
980.
Rotational viscosity of a liquid crystal mixture: a fully atomistic molecular dynamics study 下载免费PDF全文
Fully atomistic molecular dynamics (MD) simulations at 293, 303 and
313~K have been performed for the four-component liquid crystal
mixture, E7, using the software package Material Studio. Order
parameters and orientational time correlation functions (TCFs) were
calculated from MD trajectories. The rotational viscosity
coefficients (RVCs) of the mixture were calculated using the
Nemtsov--Zakharov and Fialkowski methods based on
statistical-mechanical approaches. Temperature dependences of RVC
and density were discussed in detail. Reasonable agreement between
the simulated and experimental values was found. 相似文献