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A novel vertical stack heterostructure CMOSFET is investigated, which is
structured by strained SiGe/Si with a hole quantum well channel in the
compressively strained Si量子信道 异质结构 CMOSFET 量子论 量子阱 strained SiGe/Si, quantum well channel, heterostructure CMOSFET, poly-SiGe gate Project supported by the Preresearch from National Ministries and Commissions (Grant Nos 51408061104DZ01, 51439010904DZ0101). 2/2/2006 12:00:00 AM 2006-01-022006-03-16 A novel vertical stack heterostructure CMOSFET is investigated, which is structured by strained SiGe/Si with a hole quantum well channel in the compressively strained Sil-xGex layer for p-MOSFET and an electron quantum well channel in the tensile strained Si layer for n-MOSFET. The device possesses several advantages including: 1) the integration of electron quantum well channel with hole quantum well channel into the same vertical layer structure; 2) the gate work function modifiability due to the introduction of poly-SiGe as a gate material; 3) better transistor matching; and 4) flexibility of layout design of CMOSFET by adopting exactly the same material lays for both n-channel and p-channel. The MEDICI simulation result shows that p-MOSFET and n-MOSFET have approximately the same matching threshold voltages. Nice performances are displayed in transfer characteristic, transconductance and cut-off frequency. In addition, its operation as an inverter confirms the CMOSFET structured device to be normal and effective in function. 相似文献
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A detailed numerical calculation on the phonon-assisted intersubband transition rates of electrons in wurtzite GaN/In x Ga 1 x N quantum wells is presented. The quantum-confined Stark effect, induced by the built-in electric field, and the ternary mixed crystal effect are considered. The electron states are obtained by iteratively solving the coupled Schrdinger and Poisson equations. The dispersion properties of each type of phonon modes are considered in the derivation of Fermi’s golden rule to evaluate the transition rates. It is indicated that the interface and half-space phonon scattering play an important role in the process of 1-2 radiative transition. The transition rate is also greatly reduced by the built-in electric field. This work can be helpful for the structural design and simulation of new semiconductor lasers. 相似文献
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D. J. Paul S. A. Lynch R. Bates Z. Ikonic R. W. Kelsall P. Harrison D. J. Norris S. L. Liew A. G. Cullis P. Murzyn C. Pidgeon D. D. Arnone D. J. Robbins 《Physica E: Low-dimensional Systems and Nanostructures》2003,16(3-4):309
Intersubband electroluminescence results are presented from Si/SiGe quantum cascade emitters at 3.2 THz and at temperatures up to 150 K. The effect of adding doping into the active quantum wells was studied in addition to reduced barrier widths from previous measurements. While the current through the sample is increased by the addition of doping, the emitted power is reduced through additional free carrier absorption and Coulombic scattering. Free electron laser measurements confirm the intersubband transitions in the quantum wells of the cascade devices and produce non-radiative lifetimes of 20 ps between 4 and 150 K. 相似文献
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Nonlinear optical properties of intersubband electrons in a
3-level quantum well under intense terahertz field are
investigated by using a density matrix approach. The results show that the
terahertz fields with different frequencies cause the distinct
modulations of the intersubband absorptions. The
terahertz-induced sideband and Autler--Towns splitting in the
absorption spectrum are obtained, respectively for the
terahertz-photon energy below and close to the transition energy
between the ground and first excited state. 相似文献
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详细论述Si/SiGe量子级联激光器的工作原理,通过对比找到一组合适的Si,Ge和SiGe合金的能带参数,进而应用6×6 k·p方法计算了不同阱宽、不同Ge组分Si/Si1-xGex/Si量子阱价带量子化的空穴能级本征值及其色散关系,分析Si/Si1-xGex/Si量子阱空穴态能级间距随阱宽和组分的变化规律,最后应用计算结果讨论了Si/SiGe量子级联激光器有源区的能带设计,有益于优化Si /SiGe量子级联激光器结构.
关键词:
硅锗材料
量子级联激光器
子带跃迁
k·p方法')" href="#">k·p方法 相似文献
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Shulin Gu Ronghua Wang Ping Han Liqun Hu Rong Zhang Youdou Zheng 《Superlattices and Microstructures》1992,12(4)
Infrared absorption has been used to investigate the subband structures in SiGe/Si quantum wells. The quantum wells are prepared using RRH/VLP-CVD and consist of 20 periods of
and 60 periods of
. The good periodical and interface sharpness of the SiGe/Si quantum wells have been shown by Auger Electron Spectroscopy (AES). The absorption peaks due to transitions between the hole subbands and the conduction band have been observed in infrared absorption spectra. The transverse photocurrent spectrum parallel to the growth plane have also shown absorption peaks due to transitions between the heavy and light hole band states and the conduction band states in quantum wells. 相似文献
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结合了“栅极工程”和“应变工程”二者的优点, 异质多晶SiGe栅应变Si MOSFET, 通过沿沟道方向使用不同功函数的多晶SiGe材料, 在应变的基础上进一步提高了MOSFET的性能. 本文结合其结构模型, 以应变Si NMOSFET为例, 建立了强反型时的准二维表面势模型, 并进一步获得了其阈值电压模型以及沟道电流的物理模型. 应用MATLAB对该器件模型进行了分析, 讨论了异质多晶SiGe栅功函数及栅长度、衬底SiGe中Ge组分等参数对器件阈值电压、沟道电流的影响, 获得了最优化的异质栅结构. 模型所得结果与仿真结果及相关文献给出的结论一致, 证明了该模型的正确性. 该研究为异质多晶SiGe栅应变Si MOSFET的设计制造提供了有价值的参考.
关键词:
异质多晶SiGe栅
应变Si NMOSFET
表面势
沟道电流 相似文献
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A detailed numerical calculation on the phonon-assisted intersubband transition rates of electrons in wurtzite GaN/InxGa1-xN quantum wells is presented. The quantum-confined Stark effect induced by the built-in electric field and the ternary mixed crystal effect are considered. The electron states are obtained by iteratively solving the coupled Schrödinger and Poisson equations and the dispersion property of each type of phonon modes is considered in the derivation of Fermi's golden rule to evaluate the transition rates. It is indicated that the interface and half-space phonon scattering play an important role in the process of 1-2 radiative transition. The transition rate is also greatly reduced by the built-in electric field. The present work can be helpful for the structural design and simulation of new semiconductor lasers. 相似文献
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由于ZnO缓冲层对纤锌矿ZnO/Mg_xZn_(1-x)O有限深单量子阱结构左垒的限制作用,导致阱和右垒的尺寸、Mg组分值等因素将影响系统中形成二能级.本文考虑内建电场、导带弯曲及材料掺杂对实际异质结势的影响,利用有限差分法数值求解Schr?dinger方程,获得电子的本征能级和波函数,探讨ZnO缓冲层对此类量子阱形成二能级系统的尺寸效应及三元混晶效应的影响;利用费米黄金法则探讨缓冲层、左垒、阱及右垒宽度和三元混晶效应对此类量子阱电子子带间跃迁光吸收的影响.计算结果显示:对于加入ZnO缓冲层的ZnO/Mg_xZn_(1-x)O有限深单量子阱二能级系统,左垒宽度临界值会随着阱宽和Mg组分值的增大而逐渐减小,随着右垒宽度和缓冲层厚度的增大而逐渐增大;量子阱中电子子带间跃迁光吸收峰会随着左垒、右垒尺寸以及Mg组分的增大发生蓝移,随着阱宽增大而发生红移.本文所得结果可为改善异质结器件的光电性能提供理论指导. 相似文献
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Junya Matsunami Mitsuaki Ooya Tohru Okamoto 《Physica E: Low-dimensional Systems and Nanostructures》2006,34(1-2):248
We report electrically detected electron spin resonance (ESR) measurements of a high mobility two-dimensional (2D) electron system formed in a Si/SiGe quantum well, with millimeter wave in a high magnetic field . The negative ESR signal observed under an in-plane magnetic field gives direct evidence that the spin polarization leads to a resistance increase in the 2D metallic state. Suppression of spin decoherence was observed in the quantum Hall state at the Landau level filling factor ν=2. Strength of the nuclear magnetic field in the resonance is evaluated to be less than , much smaller than that reported for GaAs/AlGaAs heterostructures. 相似文献
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《Superlattices and Microstructures》1996,20(2):237-243
We present a detailed study of the polarization dependence of subband absorption and photoconductivity in Si/SiGe quantum wells. For samples with a hole concentration ofps2.8×1012 cm2, bothp- ands-polarized absorptions have been observed and transitions to several excited states are clearly identified by comparison with self-consistent Luttinger-Kohn type calculations. The photoconductivity is surprisingly insensitive to the polarization, which indicates the importance of the subsequent transport process on the photocurrent responsitivity. 相似文献
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Influence of applied electric field on the absorption coefficient and subband distances in asymmetrical AlN/GaN coupled double quantum wells 下载免费PDF全文
The influence of applied electric fields on the absorption
coefficient and subband distances in asymmetrical AlN/GaN coupled
double quantum wells (CDQWs) has been investigated by solving
Schr?dinger and Poisson equations self-consistently. It is found
that the absorption coefficient of the intersubband transition
(ISBT) between the ground state and the third excited state (1odd-2even) can be equal to zero when the electric fields
are applied in asymmetrical AlN/GaN CDQWs, which is related to
applied electric fields induced symmetry recovery of these states.
Meanwhile, the energy distances between 1odd-2even
and 1even-2even subbands have different
relationships from each other with the increase of applied electric
fields due to the different polarization-induced potential drops
between the left and the right wells. The results indicate that an
electrical-optical modulator operated within the opto-communication
wavelength range can be realized in spite of the strong
polarization-induced electric fields in asymmetrical AlN/GaN CDQWs. 相似文献
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利用应变SiGe/Si异质pn结电容-电压(C-V)特性确定SiGe禁带宽度的技术.该技术根据SiGe/Si异质pn结C-V实验曲线,计算出 pn结接触电势差,并得到SiGe/Si的价带偏移量和导带偏移量,进而求得SiGe禁带宽度.该技术测试方法简便,其过程物理意义清晰,既适用于分立的SiGe/Si异质pn结,也可直接分析SiGe/Si异质结器件中的SiGe 禁带宽度.实验结果与理论计算及其他相关文献报道的结果符合较好.
关键词:
SiGe/Si
异质pn结
C-V
禁带宽度 相似文献