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31.
Hot-carrier degradation for 90nm gate length LDD-NMOSFET with ultra-thin gate oxide under low gate voltage stress 下载免费PDF全文
The hot-carrier degradation for 90~nm gate length lightly-doped drain
(LDD) NMOSFET with ultra-thin (1.4~nm) gate oxide under the low gate
voltage (LGV) (at Vg=Vth, where Vth is the
threshold voltage) stress has been investigated. It is found that the
drain current decreases and the threshold voltage increases after the
LGV (Vg=Vth stress. The results are opposite to the
degradation phenomena of conventional NMOSFET for the case of this
stress. By analysing the gate-induced drain leakage (GIDL) current
before and after stresses, it is confirmed that under the LGV stress
in ultra-short gate LDD-NMOSFET with ultra-thin gate oxide, the hot
holes are trapped at interface in the LDD region and cannot shorten
the channel to mask the influence of interface states as those in
conventional
NMOSFET do, which leads to the different degradation phenomena from those of the
conventional NMOS devices. This paper also discusses the degradation in the
90~nm gate length LDD-NMOSFET with 1.4~nm gate oxide under the LGV stress at
Vg=Vth with various drain biases. Experimental results show that
the degradation slopes (n) range from 0.21 to 0.41. The value of
n is
less than that of conventional MOSFET (0.5-0.6) and also that of the long gate
length LDD MOSFET (\sim0.8). 相似文献
32.
33.
首先回顾了有磁荷(或等效磁荷)存在的情况下电磁场双四维势的描述方法,给出了场强与双四维势的关系以及具有电磁对偶对称性的Maxwell方程;利用Green函数法求出了场方程具有Lorentz变换协变性的推迟解;最后给出了广义李纳-魏谢尔势的表述形式. 相似文献
34.
In this paper we study the bilayer quantum Hall (QH) effect on a noncommutative phase space (NCPS). By using perturbation theory, we calculate the energy spectrum, eigenfunction, Hall current, and Hall conductivity of the bilayer QH system, and express them in terms of noncommutative parameters θ and θ^-, respectively. In our calculation, we assume that these parameters vary from laver to laver. 相似文献
35.
非对易相空间中角动量的分裂 总被引:10,自引:0,他引:10
非对易空间效应是一种在弦尺度下出现的物理效应. 本文首先介绍了在Schwinger表象中角动量的3个分量用产生--消灭算符的表示形式, 接着讨论了非对易相空间的量子力学代数; 然后用对易空间谐振子的产生-消灭算符表示出了在非对易情况下的角动量; 最后讨论了非对易相空间中角动量的分裂. 相似文献
36.
37.
金属在“超颖物质”中有重要应用,分析和仿真金属介质很有意义. 对比了时域有限差分(FDTD)中金属介质的三种计算方法:ADE(Auxiliary Differential Equation), PLRC(Piecewise Linear Recursive Convolution) 和Sakoda提出的方法. 通过数值验证,发现ADE和PLRC的数值结果完全相同. Sakoda的方法在计算卷积时采用台阶近似,有一定误差.改进Sakoda方法的卷积计算后,结果与其他两种方法完全相同.
关键词:
超颖物质
金属
FDTD
ADE
PLRC 相似文献
38.
A kind of microstructured polymer optical fiber with elliptical core has been fabricated by adopting in- situ chemical polymerization technology and the secondary sleeving draw-stretching technique.Microscope photography demonstrates the clear hole-structure retained in the fiber.Though the holes distortion is visible,initial laser experiment indicates that light can be strongly confined in the elliptical core region, and the mode field is split obviously and presents the multi-mode characteristic.Numerical modeling is carried out for the real fiber with the measured parameters,including the external diameter of 150μm,the average holes diameter of 3.3μm,and the average hole spacing of 6.3μm by using full-vector plane wave method.The guided mode fields of the numerical simulation are consistent with the experiment result. This fiber shows the strong multi-mode and weak birefringence in the visible and near-infrared band,and has possibility for achieving the fiber mode convertors,mode selective couplers and so on. 相似文献
39.
We calculate the long-range Van der Waals force and the photoelectric cross section in a noncommutative setup. It is argued that non-commutativity effects could not be discerned for the Van der Waals interactions. The result for the photoelectric effect shows deviation from the usual commutative one, which in principle can be used to put bounds on the space-space non-commutativity parameter. 相似文献
40.
本文主要回顾了电磁场的对偶性和电荷量子化解释,并把电磁场的对偶性推广到了一般线性介质状况,讨论了磁单极及其整体规范变换,并给出了Dirac磁单极产生的磁矢势的普遍表达式;最后给出了Maxwell方程的U(1)对称性及其对偶性的费米子描述方法。 相似文献