多晶SiGe栅量子阱pMOSFET阈值电压模型

本文基于多晶SiGe栅量子阱SiGe pMOSFET器件物理,考虑沟道反型时自由载流子对器件纵向电势的影响,通过求解泊松方程,建立了p+多晶SiGe栅量子阱沟道pMOS阈值电压和表面寄生沟道开启电压模型.应用MATLAB对该器件模型进行了数值分析,讨论了多晶Si_1-yGe_y栅Ge组分、Si_1-xGe_x量子阱沟道Ge组分、栅氧化层厚度、Si帽层厚度、沟道区掺杂浓度和 关键词： 多晶SiGe栅 寄生沟道 量子阱沟道 阈值电压     

含有δ掺杂层的SiGe pMOS量子阱沟道空穴面密度研究

建立了含有δ掺杂层的SiGe pMOS器件量子阱沟道中空穴面密度的静态与准静态物理模型，并对该模型进行了数值分析.讨论了静态时器件量子阱空穴面密度与δ掺杂层杂质浓度和本征层厚度的关系，阈值电压VT与δ掺杂层杂质浓度NA、量子阱沟道载流子面密度Ps及本征层厚度di等参数间的关系.同时还讨论了准静态时量子阱空穴面密度P′s与栅压VGS的关系. 关键词： δ掺杂层 空穴面密度     

应变SiGe SOI量子阱沟道PMOSFET阈值电压模型研究

在绝缘层附着硅(SOI)结构的Si膜上生长SiGe合金制作具有SiGe量子阱沟道的SOI p型金属氧化物半导体场效应晶体管(PMOSFET)，该器件不仅具有SOI结构的优点，而且因量子阱中载流子迁移率高，所以进一步提高了器件的性能.在分析常规的Si SOI MOSFET基础上，建立了应变SiGe SOI 量子阱沟道PMOSFET的阈值电压模型和电流-电压(I-V)特性模型，利用Matlab对该结构器件的I-V特性、跨导及漏导特性进行了模拟分析，且与常规结构的器件作了对比.模拟结果表明，应变SiGe SOI量子阱沟道PMOSFET的性能均比常规结构的器件有大幅度提高. 关键词： 应变SiGe SOI MOSFET 阈值电压 模型     

SiGe/Si量子阱的低温光荧光和电注入发光

使用Si-MBE生长了阶梯形折射率分布SiGe/Si量子阱材料,在低温下观测到无声子参与的光荧光和电注入发光。阶梯形折射率分布SiGe/Si电子阱结构有利于提高发光效率。讨论了这种结构的光学和电学特性。     

空穴在动量空间分布对p型量子阱红外探测器响应光谱的影响

通过对p型量子阱红外探测器(QWIP)的自洽计算，得到了量子阱价带的电子结构和器件的光电流谱，并研究了载流子在动量空间分布对p型QWIP光谱响应的影响.计算结果表明，在动量空间不同区域的空穴对器件的光谱响应起着不同作用，从而使得在p型QWIP中，空穴浓度和温度都将影响器件的响应光谱.所得结果合理地解释了实验中器件响应光谱随掺杂浓度和温度的变化. 关键词： p型量子阱红外探测器 响应光谱 空穴浓度 温度     

亚100 nm应变Si/SiGe nMOSFET阈值电压二维解析模型

本文基于二维泊松方程,建立了适用于亚100 nm应变Si/SiGe nMOSFET的阈值电压理论模型.为了保证该模型的准确性,同时考虑了器件尺寸减小所导致的物理效应,如短沟道效应,量子化效应等.通过将模型的计算结果与二维器件模拟器ISE的仿真结果进行对比分析,证明了本文提出的模型的正确性.最后,还讨论了亚100 nm器件中常规工艺对阈值电压的影响.该模型为亚100 nm小尺寸应变Si器件的分析设计提供了一定的参考. 关键词： 亚100nm 应变Si/SiGe nMOSFET 二维表面势 阈值电压     

考虑量子效应的短沟道MOSFET二维阈值电压模型

通过数值方法求解泊松方程和薛定谔方程的自洽解，提出了考虑量子效应时不同于经典理论的阈值条件，并得出了精确的一维阈值电压模型，模拟结果与实验十分符合.在此基础上，基于准二维泊松方程，通过考虑短沟道效应和量子效应，建立了较为精确的适合于小尺寸MOSFET的量子修正阈值电压模型,模型同样适用于(超)深亚微米高k栅介质MOSFET电特性的模拟和结构参数的设计. 关键词： 阈值电压 量子效应 短沟道效应 高k栅介质     

Si/SiGe量子级联激光器研究进展

Si／SiGe量子级联激光器是一种新型的带内跃迁的红外光源，突破了Si基材料间接带隙特性对光跃迁的限制。Si/SiGe量子级联激光器的开发将为实现太赫兹有源器件的硅基集成产生深远影响。文章介绍了Si/SiGe量子级联激光器的工作原理，以及这类激光器在能带设计、材料生长和波导制作方面的最新进展。     

Si/SiGe量子级联激光器研究进展

Si/SiGe量子级联激光器是一种新型的带内跃迁的红外光源,突破了Si基材料间接带隙特性对光跃迁的限制.Si/SiGe量子级联激光器的开发将为实现太赫兹有源器件的硅基集成产生深远影响.文章介绍了Si/SiGe量子级联激光器的工作原理,以及这类激光器在能带设计、材料生长和波导制作方面的最新进展.     

SiGe/Si多量子阱中的光致子带间吸收研究

本文论述了硅锗量子阱中的光致子带间吸收的机理,并在实验中探测SiGe/Si量子阱价带间的红外光致吸收.载流子由氩离子激光器作为光泵浦源产生,所导致的红外吸收由一个步进式傅里叶变换光谱仪来探测.在硅锗量子阱中的光致吸收有两个来源:类似单一掺杂的SiGe薄层的体吸收的自由载流子吸收,及量子阱价带的子带间吸收.实验探测了TE和TM偏振方向的吸收.TM偏振方向的吸收是由偏离布里渊带中心的载流子的跃迁所造成的.我们认为这种光致吸收技术在研究价带耦合效应及其对子带间吸收的影响是非常有效的.     

Novel vertical stack HCMOSFET with strained SiGe/Si quantum channel

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 gateProject supported by the Preresearch from National Ministries and Commissions (Grant Nos 51408061104DZ01, 51439010904DZ0101).2/2/2006 12:00:00 AM2006-01-022006-03-16A 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.     

锗硅量子阱中近带边光跃迁的理论和实验研究

本文研究了SiGe/Si量子阱中近带边光跃迁的产生机制,对由杂质无规分布引起的近带边光跃迁给出了一个物理模型。用此模型计算了光跃迁偶极矩,给出了跃迁偶极矩的上限。提出了未掺杂SiGe/Si量子阱中近带边光跃迁的一种跃迁机制,认为是Ge原子周围波函数畸变的集体行为。用MBE方法生长了掺杂SiGe/Si量子阱材料,在低温下观测到近带边光跃迁。     

Intraband photoresponse of SiGe quantum dot/quantum well multilayers

In this contribution we study the intravalence band photoexcitation of holes from self-assembled Ge quantum dots (QDs) in Si followed by spatial carrier transfer into SiGe quantum well (QW) channels located close to the Ge dot layers. The structures show maximum response in the important wavelength range 3–5 μm. The influence of the SiGe hole channel on photo- and dark current is studied depending on temperature and the spatial separation of QWs and dot layers. Introduction of the SiGe channel in the active region of the structure increases the photoresponsivity by up to about two orders of magnitude to values of 90 mA/W at T=20 K. The highest response values are obtained for structures with small layer separation (10 nm) that enable efficient transfer of photoexcited holes from QD to QW layers. The results indicate that Si/Ge QD structures with lateral photodetection promise very sensitive large area mid-infrared photodetectors with integrated readout microelectronics in Si technology.     

Si/SiGe量子级联激光器的能带设计

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/Si_1-xGe_x/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/Si_1-xGe_x/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     

Electroluminescence from Si/SiGe quantum cascade emitters

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.     

Electron spin resonance of the two-dimensional metallic state and the quantum Hall state in a Si/SiGe quantum well

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.     

Strain compensated Si/SiGe quantum well and quantum cascade on Si0.5Ge0.5 pseudosubstrate

This study follows up our previous investigation of the valence band (VB) intersubband emission from quantum cascade structures grown lattice matched on Si substrates. Here, Si/Si_1−xGe_x (x=80%) heterostructures are investigated which are deposited by MBE on a virtual substrate of relaxed SiGe containing 50% of Ge. TEM analysis reveal flat and abrupt interfaces for structures grown at temperatures T_growth≈300°C. Intersubband absorption and photoluminescence emission manifest well-defined interfaces and good material quality. The observed intersubband line positions are found to be in good agreement with k·p model calculations for the VB. This is in contrast to the observed type II no phonons recombination which is found at consistently lower energy than expected. Finally, electrically excited intersubband emission from a strain compensated cascade structure containing three periods is presented.     

单Halo全耗尽应变Si 绝缘硅金属氧化物半导体场效应管的阈值电压解析模型

为了改善金属氧化物半导体场效应管(MOSFET) 的短沟道效应(SCE)、 漏致势垒降低(DIBL) 效应, 提高电流的驱动能力, 提出了单Halo 全耗尽应变硅绝缘体 (SOI) MOSFET 结构, 该结构结合了应变Si, 峰值掺杂Halo结构, SOI 三者的优点. 通过求解二维泊松方程, 建立了全耗尽器件表面势和阈值电压的解析模型. 模型中分析了弛豫层中的Ge组分对表面势、表面场强和阈值电压的影响, 不同漏电压对表面势的影响, Halo 掺杂对阈值电压和DIBL的影响.结果表明, 该新结构能够抑制SCE和DIBL效应, 提高载流子的输运效率. 关键词： 应变Si 阈值电压 短沟道效应 漏致势垒降低