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利用Keating模型计算了Si(1-x)Gex合金中Si—Si,Ge—Ge和Si—Ge三种振动模态的拉曼频移,计算分别获得Ge浓度为01,05和09时,Si—Ge的振动拉曼频移分别为40275,41339和38815 cm-1,这些结果与文献的实验结果符合,证明了Keating模型建立的关于原子振动模型是有效的,并可以利用拉伸压缩和相邻原子键之间弹性系数变化获得处于应变状态的拉曼光谱频率.利用Kea
关键词:
Keating模型
拉曼光谱
(1-x)Gex')" href="#">Si(1-x)Gex
非晶硅 相似文献
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Damage effect and mechanism of the GaAs high electron mobility transistor induced by high power microwave 下载免费PDF全文
In this paper, we present the damage effect and mechanism of high power microwave(HPM) on Al GaAs/GaAs pseudomorphic high-electron-mobility transistor(p HEMT) of low-noise amplifier(LNA). A detailed investigation is carried out by simulation and experiment study. A two-dimensional electro-thermal model of the typical GaAs p HEMT induced by HPM is established in this paper. The simulation result reveals that avalanche breakdown, intrinsic excitation, and thermal breakdown all contribute to damage process. Heat accumulation occurs during the positive half cycle and the cylinder under the gate near the source side is most susceptible to burn-out. Experiment is carried out by injecting high power microwave into GaAs p HEMT LNA samples. It is found that the damage to LNA is because of the burn-out at first stage p HEMT. The interiors of the damaged samples are observed by scanning electron microscopy(SEM) and energy dispersive spectrometer(EDS). Experimental results accord well with the simulation of our model. 相似文献
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测量了采用离子注入法得到掺N的n-SiC晶体从100—450 K的拉曼光谱. 研究了SiC一级拉曼谱、电子拉曼散射谱及二级拉曼谱的温度效应. 实验结果表明,大部分SiC一级拉曼峰会随温度升高向低波数方向移动,但声学模红移(峰值位置向低频方向移动)的幅度较光学模小. 重掺杂4H-SiC的纵光学声子等离子体激元耦合(LOPC)模频率随温度升高表现出先蓝移(峰值位置向高频方向移动)后红移的变化趋势,表明LOPC模的温度特性不仅会受到非简谐效应的影响,还与实际已离化杂质浓度有关. 电子拉曼散射峰线宽随温度升高而增
关键词:
碳化硅
温度
纵光学声子等离子体激元耦合模
电子拉曼散射 相似文献
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Based on the multilevel interconnections temperature distribution model and the RLC interconnection delay model of the integrate circuit,this paper proposes a multilevel nano-scale interconnection RLC delay model with the method of numerical analysis,the proposed analytical model has summed up the influence of the configuration of multilevel interconnections,the via heat transfer and self-heating effect on the interconnection delay,which is closer to the actual situation.Delay simulation results show that the proposed model has high precision within 5% errors for global interconnections based on the 65 nm CMOS interconnection and material parameter,which can be applied in nanometer CMOS system chip computer-aided design. 相似文献
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目的设计可工作在高温下的6H-SiC CMOS运算放大器。方法该电路基于标准的PMOS输入两级运放而成,考虑泄漏电流匹配添加Dcomp二极管。利用零温度系数理论和泄漏电流匹配的原则对电路管子的尺寸进行确定。通过求解SiMOS管和6H-SiC MOS管零温度系数点来稳定偏置电路。结果利用Hspice进行仿真,当温度从300K变化到600K时,SiC运放的增益和相位裕度的变化率分别为2.5%和3.3%,而Si电路的增益从300K的64dB降到600K的-80dB。由于SiC MOS器件沟道迁移率低导致器件的跨导低于相同尺寸下的Si器件,所以其开环增益也小于相同结构和尺寸的Si OPAMP。结论此电路可以在高温下稳定工作,但是单管的性能较Si单管差。 相似文献
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研究了利用离子注入法得到的掺氮n-SiC拉曼光谱. 理论线形分析表明,与4H-SiC相比,6H-SiC中LO声子等离子体激元耦合模(LOPC模)拉曼位移随自由载流子浓度变化较小. 5145nm激发光下得到的电子拉曼散射光谱表明,k位处由1s(A1)到1s(E)的能谷轨道跃迁带来的拉曼谱6H-SiC中有四条,4H-SiC中有二条;高频6303及635cm-1处观察到的谱线被认为与深能级缺陷有关. 最后,利用纤锌矿型结构二级拉曼散射选择定则指认了6
关键词:
碳化硅
电子拉曼散射
轨道能谷分裂
倍频谱 相似文献
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建立了PNP型达林顿管的二维电热模型,对处于有源放大区的达林顿管的集电极注入高功率微波(HPM)和强电磁脉冲(EMP)时的瞬态响应进行了仿真。结果表明:HPM注入下,器件内部的峰值温度呈周期性的"下降-上升",温度升高过程发生在信号的正半周,靠近达林顿管发射极的晶体管发射结边缘是最易毁伤处;EMP注入下,其损伤机理与HPM注入时的正半周时相似,器件内部峰值温度一直上升,易毁伤部位与HPM注入时相同。得到了损伤功率阈值和损伤能量阈值与损伤脉宽的关系,这两种干扰注入下的损伤能量阈值-脉宽关系和损伤功率阈值-脉宽关系公式相似,并且在相同脉宽下,HPM注入下的损伤能量阈值大于EMP注入下的损伤能量阈值。 相似文献
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