能量回收电路的功耗优化方法

能量回收电路的非绝热损失正比于CLΔV2,文中提出了两种方法降低CL和ΔV因子.HEERL(high efficient energy recovery logic)电路利用自举效应减小了回收节点的残留电压ΔV,IERL(improved energy recovery logic)电路增加了回收的通路,在控制回收通路的小电容节点产生了CAΔV2的非绝热损失,从而使大电容输出节点电荷被充分回收,降低了电路的整体功耗.降低非绝热损失两个因子CL和ΔV的能量回收电路与其它能量回收电路相比,电路面积增加很小(2个NMOS管),而功耗可降低50%以上.     

能量回收电路的功耗优化方法

能量回收电路的非绝热损失正比于CLΔV2,文中提出了两种方法降低CL和ΔV因子.HEERL(high efficient energy recovery logic)电路利用自举效应减小了回收节点的残留电压ΔV,IERL(improved energy recovery logic)电路增加了回收的通路,在控制回收通路的小电容节点产生了CAΔV2的非绝热损失,从而使大电容输出节点电荷被充分回收,降低了电路的整体功耗.降低非绝热损失两个因子CL和ΔV的能量回收电路与其它能量回收电路相比,电路面积增加很小(2个NMOS管),而功耗可降低50%以上.     

一种改进的能量回收逻辑电路

文本分析了能量回收电路的功耗组成，指出非绝热损失是能量回收电路的主要功耗能量来源，提出了一种改进的能量回收逻辑电路IERL。IERL电路增加了额外的回收路径，能够显著降低电路的非绝热损失，HSPICE模拟结果表明，IERL电路具有很好的低功耗性能。同时，给出了IERL电路的复杂逻辑门设计与级联方式，用0．8μm DPDM工艺实现了2位IERL全加器电路和两相正弦功率时钟电路。     

二种EPAL绝热开关电路

研究和设计了两种低功耗的EPAL(efficient PAL)绝热开关电路.这两种电路均采用逐级相位落后90°的四相正弦功率时钟.讨论了EPAL电路的设计方法,并在不同时钟频率和不同的负载条件下用1.2μm的CMOS工艺参数对所设计的电路进行PSPICE模拟.模拟结果表明这两类电路均能完成正确的逻辑功能.两种EPAL的五级反相器/缓冲器电路在功率时钟频率为10MHz时都比相应的PAL-2N电路节省80%以上的功耗,在400MHz时功耗节省也分别可达23%和50%.EPAL电路可以工作于更高的时钟频率,有更强的驱动负载能力和更低的输出波形畸变.     

二种EPAL绝热开关电路

研究和设计了两种低功耗的EPAL(efficientPAL)绝热开关电路.这两种电路均采用逐级相位落后90°的四相正弦功率时钟.讨论了EPAL电路的设计方法,并在不同时钟频率和不同的负载条件下用1.2μm的CMOS工艺参数对所设计的电路进行PSPICE模拟.模拟结果表明这两类电路均能完成正确的逻辑功能.两种EPAL的五级反相器/缓冲器电路在功率时钟频率为10MHz时都比相应的PAL-2N电路节省80%以上的功耗,在400MHz时功耗节省也分别可达23%和50%.EPAL电路可以工作于更高的时钟频率,有更强的驱动负载能力和更低的输出波形畸变     

能量回收阈值逻辑及其功率时钟产生电路

提出了能量回收阈值逻辑电路(ERTL).该电路把阈值逻辑应用到绝热电路中,降低能耗的同时也降低了电路的门复杂度.并且提出了一种高效率的功率时钟产生电路.该功率时钟电路能够根据逻辑的复杂度和工作频率,调整电路中MOS开关的开启时间,以取得最优的能量效率.为了便于功率时钟的优化设计,推导出了闭式结果.基于0.35μm的工艺参数,设计并且仿真了ERTL可编程逻辑阵列(PLA)和普通结构PLA.在20～100MHz的工作频率范围内,提出的功率时钟电路的能量效率可以达到77%～85%.仿真结果还显示,ERTL是一个低能耗的逻辑.ERTL PLA与普通结构的PLA相比,包括功率时钟电路的功耗在内,ERTL PLA仍节省65%～77%的功耗.     

具有反馈结构的PAL-2NF电路

在分析PAL-2N电路缺陷产生原因的基础上,提出了一种低功耗,具有反馈结构的PAL-2NF电路,它采用逐级相位落后90°的四相正弦功率时钟.讨论了PAL-2NF电路的设计方法,并在不同时钟频率下用1.2μm的CMOS工艺参数对所设计的电路进行PSPICE模拟,电路能完成正确的逻辑功能.五级级联的PAL-2NF反相器/缓冲器电路在功率时钟频率10MHz时都比相应的PAL-2N电路节省93%以上的功耗,在400MHz时功耗节省也可达40%.由于几乎完全消除了输出端的悬空现象和逻辑0的"第三态"现象,PAL-2NF电路可以工作于更高的时钟频率和更低的输出波形畸变.     

具有反馈结构的PAL-2NF电路

在分析PAL - 2 N电路缺陷产生原因的基础上,提出了一种低功耗,具有反馈结构的PAL - 2 NF电路,它采用逐级相位落后90°的四相正弦功率时钟.讨论了PAL - 2 NF电路的设计方法,并在不同时钟频率下用1 .2μm的CMOS工艺参数对所设计的电路进行PSPICE模拟,电路能完成正确的逻辑功能.五级级联的PAL - 2 NF反相器/缓冲器电路在功率时钟频率1 0 MHz时都比相应的PAL - 2 N电路节省93%以上的功耗,在4 0 0 MHz时功耗节省也可达4 0 % .由于几乎完全消除了输出端的悬空现象和逻辑0的“第三态”现象,PAL - 2 NF电路可以工作于更高的时钟频率和更低的输出波形畸变     

开关信号理论与绝热CMOS电路设计

重新定义了钟控信号的表示方法,发展了适用于绝热电路的开关级设计理论.设计了实现全部钟控信号的基本单元电路,这些电路包括单轨和双轨结构,并给出了它们的多种级联方式.所提出电路的功耗与其他绝热电路相当,并工作于二相正弦功率时钟,因此可降低时钟电路的设计难度.这些电路可分别应用于需要基0信号和基1信号的绝热电路设计中.与以往大部分绝热电路不同的是,应用所提出的电路结构可以实现在同一时钟相位有多级电路同时参加运算.这一特性可以有效减少实现复杂逻辑电路时的等待时间以及实现流水结构时所需插入的缓冲器数目.通过对基0信号2∶1数据选择器     

开关信号理论与绝热CMOS电路设计

重新定义了钟控信号的表示方法,发展了适用于绝热电路的开关级设计理论.设计了实现全部钟控信号的基本单元电路,这些电路包括单轨和双轨结构,并给出了它们的多种级联方式.所提出电路的功耗与其他绝热电路相当,并工作于二相正弦功率时钟,因此可降低时钟电路的设计难度.这些电路可分别应用于需要基0信号和基1信号的绝热电路设计中.与以往大部分绝热电路不同的是,应用所提出的电路结构可以实现在同一时钟相位有多级电路同时参加运算.这一特性可以有效减少实现复杂逻辑电路时的等待时间以及实现流水结构时所需插入的缓冲器数目.通过对基0信号2∶1数据选择器和基1信号全加器的设计及SPICE模拟,验证了所提出设计技术的有效性以及电路的低功耗特性.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

GaAsSb/InAlAs PA DHBTs Grown by Production MBE

The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO＞6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.     

Noise character analysis and the restraint of self-pulsation laser diodes

We calculate the Langevin noise sources of self-pulsation laser diodes, analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation, and propose a novel method to restrain the noise effects. A visible SIMULINK model is established to simulate the system, The results indicate that the effects of noise in absorption region can be ignored; that with the increase of DC injecting current, the noise effects enhance power jitter, and nevertheless, the period jitter is decreased; and that with external sinusoidal current modulating the self-pulsation laser diode, the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.     

High-quality single-crystal CdSe nanoribbons and their optical properties

Large-scale synthesis of single-crystal CdSe nanoribbons is achieved by a modified thermal evaporation method, in which two-step-thermal-evaporation is used to control CdSe sources＇ evaporation. The synthesized CdSe nanoribbons are usually several micrometers in width, 50 nm in thickness, and tens to several hundred micrometers in length. Studies have shown that high-quality CdSe nanoribbons with regular shapes can be obtained by this method. Room-temperature photolumines-cence indicates that the lasing emission at 710 nm has been observed under optical pumping （266 nm） at power densities of 25-153 kW/cm^2. The full width half maximum （FWHM） of the lasing mode is 0.67 nm     

Propagation of hermite-cosh-gaussian beams passing through ABCD optical system with an annular aperture

By using the expansion of the aperture function into a finte sum of complex Gaussian functions, the corresponding analytical expressions of Hermite-cosh-Gaussian beams passing through annular apertured paraxially and symmetrically optical systems written in terms of ABCD matrix were derived, and they could reduce to the cases with squared aperture. In a similar way, the corresponding analytical expressions of cosh-Gaussian beams through annular apertured ABCD matrix were also given. The method could save more calculation time than that by using the diffraction integral formula directly.     

Influence of polarization extinction ratio on distributed polarization coupling detection

Distributed polarization coupling in polarization-maintaining fibers can be detected by using a white light Michelson interferometer. This technique usually requires that only one polarization mode is excited. However, in practical measurement, the injection polarization direction could not be exactly aligned to one of the principal axes of the PMF, so the influence of the polarization extinction ratio should be considered. Based on the polarization coupling theory, the influence of the incident polarization extinction on the measurement result is evaluated and analyzed, and a method for distributed polarization coupling detection is developed when both two orthogonal eigenmodes are excited.     

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正Communications—VLSI Researches and industries of telecommunications have been growing rapidly in the last 20 years and will keep their high growing pace in the next decade.The involved researches and developments cover mobile communications,highway and last-mile broadband communication,domain specific communications,and emerging D2D M2M communications.Radio communication steps into its