共查询到19条相似文献,搜索用时 609 毫秒
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采用量子水动力学(QHD)模型模拟了35nm Si/Si1-xGex空穴型共振隧穿二极管(RTD)在室温下的I-V特性.模拟过程中,引入second upwind,Schafetter-Gummel(SG)和二阶中心差分法相结合的离散方法对方程组进行离散,保证了结果的收敛性.还模拟了不同的器件结构,对结果的分析表明器件的势垒厚度和载流子有效质量都会对RTD的负阻效应产生影响.在室温下(T=293K),当x=0.23时,模拟结果的峰谷电流比为1.14,与实验结果相吻合. 相似文献
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采用量子水动力学(QHD)模型模拟了35nm Si/Si1-xGex空穴型共振隧穿二极管(RTD)在室温下的I-V特性.模拟过程中,引入second upwind,Schafetter-Gummel(SG)和二阶中心差分法相结合的离散方法对方程组进行离散,保证了结果的收敛性.还模拟了不同的器件结构,对结果的分析表明器件的势垒厚度和载流子有效质量都会对RTD的负阻效应产生影响.在室温下(T=293K),当x=0.23时,模拟结果的峰谷电流比为1.14,与实验结果相吻合. 相似文献
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介绍了共振隧穿二极管(RTD)中电荷积累效应,利用顺序隧穿模型分析了RTD中有电荷积累时器件各部分电压的再分布;并结合电压降局限于双势垒区和遍及整个RTD的两种情况,建立了电荷和电流方程;最后利用电荷积累效应解释了负阻区本征双稳态特性。 相似文献
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报道了共振隧穿二极管(RTD)在压力下的弛豫振荡特性.采用Pspice 8.0软件仿真并设计了振荡电路,测得其振荡频率达200kHz.在(100)半绝缘(SI)GaAs衬底上利用分子束外延(MBE)技术生长了AlAs/InxGa1-xAs/GaAs双势垒共振隧穿结构(DBRTS),并采用Au/Ge/Ni/Au金属化和空气桥结构成功加工出了RTD.由于RTD的压阻效应,采用显微喇曼光谱仪标定所加应力大小,对RTD在加压条件下的振荡特性进行了研究,结果表明其弛豫振荡频率大致有-17.9kHz/MPa的改变量. 相似文献
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D. Y. C. Lie 《Journal of Electronic Materials》1998,27(5):377-401
The question of whether one can effectively dope or process epitaxial Si(100)/GeSi heterostructures by ion implantation for
the fabrication of Si-based heterojunction devices is experimentally investigated. Results that cover several differention
species (B, C, Si, P, Ge, As, BF2, and Sb), doses (1013 to 1016/cm2), implantation temperatures (room temperature to 150°C), as well as annealing techniques (steady-state and rapid thermal
annealing) are included in this minireview, and the data are compared with those available in the literature whenever possible.
Implantation-induced damage and strain and their annealing behavior for both strained and relaxed GeSi are measured and contrasted
with those in Si and Ge. The damage and strain generated in pseudomorphic GeSi by room-temperature implantation are considerably
higher than the values interpolated from those of Si and Ge. Implantation at slightly elevated substrate temperatures (e.g.,
100°C) can very effectively suppress the implantation-induced damage and strain in GeSi. The fractions of electrically active
dopants in both Si and GeSi are measured and compared for several doses and under various annealing conditions. Solid-phase
epitaxial regrowth of GeSi amorphized by implantation has also been studied and compared with regrowth in Si and Ge. For the
case of metastable epi-GeSi amorphized by implantation, the pseudomorphic strain in the regrown GeSi is always lost and the
layer contains a high density of defects, which is very different from the clean regrowth of Si(100). Solid-phase epitaxy,
however, facilitates the activation of dopants in both GeSi and Si, irrespective of the annealing techniques used. For metastable
GeSi films that are not amorphized by implantation, rapid thermal annealing is shown to outperform steady-state annealing
for the preservation of pseudomorphic strain and the activation of dopants. In general, defects generated by ion implantation
can enhance the strain relaxation process of strained GeSi during post-implantation annealing. The processing window that
is optimized for ion-implanted Si, therefore, has to be modified considerably for ion-implanted GeSi. However, with these
modifications, the mature ion implantation technology can be used to effectively dope and process Si/GeSi heterostructures
for device applications. Possible impacts of implantation-induced damage on the reliability of Si/GeSi heterojunction devices
are briefly discussed. 相似文献
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LIU Shu-ping JIA Yue-hu 《半导体光子学与技术》2006,12(1):21-24
According to Maxwell's theory, the optical transmission characteristics in GeSi/Si superlattice nanocrystalline layer have been analyzed and calculated. The calculated result shows that when the total thickness L is 340 nm, the single mode lightwave can be transmitted only at periodic number M≥15.5. In addition, at the direction of transmission, when the transmission distance is larger than 500 μm, the lightwave intensity is decreased greatly. Based on the above parameters, the design and manufacture of GeSi/Si superlattice nanocrystalline photodetector are carried out. 相似文献
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带间共振隧穿二极管(RITD)是导带与价带间发生共振隧穿的两端器件,其特点是启始电压VT和峰值电压Vp较低,电流峰谷比PVCR较大。在导出RITD物理模型和其电流密度方程的基础上重点介绍了InAs/AlSb/GaSbⅡ类异质结RITD、n+InAlAs/InGaAs/InAlAs/In-GaAs/p+InAlAsp-n结双势阱Ⅰ类RITD以及δ掺杂RITD三种RITD的器件结构、材料结构、工作原理、器件特性和参数等,并对这三种RITD的特点进行了比较和讨论。 相似文献
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《Electron Device Letters, IEEE》2009,30(11):1173-1175
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Yuanxun Liao Pengfei Zhang Stephen Bremner Santosh Shrestha Shujuan Huang Gavin Conibeer 《Advanced functional materials》2017,27(21)
Resonant tunneling through a 4 nm nanocrystal Ge (nc‐Ge) layer and a 2.4 nm monolayer of Si colloidal quantum dots (QD) is achieved with 0.7 nm amorphous Al2O3 (a‐Al2O3) barriers. The nc‐Ge resonant tunneling diode (RTD) demonstrates a peak‐to‐valley current ratio (PVCR) of 8 and a full width at half maximum (FWHM) of 30 mV at 300 K, the best performance among RTDs based on annealed nanocrystals. The Si QD RTD is first achieved with PVCRs up to 47 and FWHMs as small as 10 mV at room temperature, confirming theoretically expected excellences of 3D carrier confinements. The high performances are partially due to the smooth profile of nc‐Ge layer and the uniform distribution of Si QDs, which reduce the adverse influences of many‐body effects. More importantly, carrier decoherence is avoided in the 0.7 nm a‐Al2O3 barriers thinner than the phase coherence length (≈1.5 nm). Ultrathin a‐Al2O3 also passivates well materials and suppresses leakage currents. Additionally, the interfacial bandgap of ultrathin a‐Al2O3 is found to be similar to the bulk, forming deep potential wells to sharpen transmission curves. This work can be easily extended to other materials, which may enable resonant tunneling in various nanosystems for diverse purposes. 相似文献
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本文介绍了A/D与D/A转换器、超高速SOI器件及电路、超高速双极电路、GeSi/Si异质结器件和电路、智能功率等模拟集成电路的发展概况。 相似文献
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P. A. Borodin A. A. Bukharaev D. O. Filatov M. A. Isakov V. G. Shengurov V. Yu. Chalkov Yu. A. Denisov 《Semiconductors》2011,45(3):403-407
The local density of states in self-assembled GeSi/Si(001) nanoislands is investigated for the first time by combined tunneling
and atomic-force scanning microscopy. Current images and tunneling spectra of individual GeSi/Si(001) islands are obtained.
These measurements yield the spatial and energy distributions of the local density of states in GeSi islands, respectively.
The tunneling spectroscopy data demonstrate that uncapped Ge0.3Si0.7/Si(001) islands behave as type-I heterostructures. 相似文献
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Nine-state resonant tunneling diode memory 总被引:1,自引:0,他引:1
The authors demonstrate an epitaxial series combination of eight pseudomorphic AlAs/In0.53Ga0.47As/InAs resonant tunneling diodes (RTDs) grown by molecular beam epitaxy on InP. This series RTD produces an eight-peak multiple negative differential resistance characteristic with a peak-to-valley current ratio (PVR) exceeding 2 per peak at a peak current density of approximately 6 kA/cm 2. Hysteresis in the current-voltage characteristic is reduced by uniformly Si doping the double-barrier resonant tunneling region at a density of 5×1016 cm-3. Using this multiple-peak RTD in series with a field-effect transistor load, a nine-state multivalued memory circuit is demonstrated 相似文献