一个新型CMOS电流模带隙基准源

介绍了一个新型电流模带隙基准源,该带隙基准源的输出基准可以设计为任意大于硅材料的带隙电压(1.25V)的电压,避免在应用中使用运算放大器进行基准电压放大.同时该结构消除了传统电流模带隙基准源的系统失调.该带隙基准源已通过UMC 0.18μm混合信号工艺验证.在1.6V电源电压下,该带隙基准源输出1.45V的基准电压,同时消耗27μA的电流.在不采用曲率补偿的情况下,输出基准的温度系数在30℃到150℃的温度范围内可以达到23ppm/℃.在电源电压从1.6变化到3V的情况下,带隙基准源的输入电压调整率为2.1mV/V.该带隙基准源在低频(10Hz)的电源电压抑制比为40dB.芯片面积(不包括Pads)为0.088mm2.     

一个电压接近1V 10ppm/℃带曲率补偿的CMOS带隙基准源

介绍了一个带曲率补偿的低电压带隙基准源.由于采用电流模结构,带隙基准源的最低电源电压为900mV.通过VEB线性化补偿技术,带隙基准源在0到150℃的温度范围内的温度系数为10ppm/℃.在电源电压为1.1V时,电源电流为43μA,低频的PSRR为55dB.该带隙基准源已通过UMC 0.18μm混合信号工艺验证,芯片面积为0.186mm2.     

一个电压接近1V 10ppm/℃带曲率补偿的CMOS带隙基准源

介绍了一个带曲率补偿的低电压带隙基准源.由于采用电流模结构,带隙基准源的最低电源电压为900mV.通过VEB线性化补偿技术,带隙基准源在0到150℃的温度范围内的温度系数为10ppm/℃.在电源电压为1.1V时,电源电流为43μA,低频的PSRR为55dB.该带隙基准源已通过UMC 0.18μm混合信号工艺验证,芯片面积为0.186mm2.     

新型电流微调CMOS带隙基准源的设计

介绍了一个新型PTAT电流微调并具有关断模式的CMOS带隙基准源,通过数字控制信号逻辑的改变,可实现1.20～1.27V的基准输出。该带隙基准源采用TSMC0.18μm工艺进行电路和版图设计。仿真结果显示,在输出基准为1.24V的情况下,带隙基准源在-40～125℃,所有工艺角下的最大误差为23.07mV,其中tt工艺角下的温度系数为21×10-6/℃。电源电压为1.8V时,电源电流为63μA;关断模式下电流为93pA。10kHz的电源抑制比为44dB。     

一种高精度带隙基准电压源电路设计

针对传统CMOS带隙电压基准源电路电源电压较高,基准电压输出范围有限等问题,通过增加启动电路,并采用共源共栅结构的PTAT电流产生电路,设计了一种高精度、低温漂、与电源无关的具有稳定电压输出特性的带隙电压源.基于0.5μm高压BiCMOS工艺对电路进行了仿真,结果表明,在-40℃～85℃范围内,该带隙基准电路的温度系数为7ppm/℃,室温下的带隙基准电压为1.215 V.     

一种新型CMOS电流模带隙基准源的设计

设计了一种新型电流模带隙基准源电路和一个3bit的微调电路。该带隙基准源可以输出可调的基准电压和基准电流,避免了在应用中使用运算放大器进行基准电压放大和利用外接高精度电阻产生基准电流的缺点,同时该结构克服了传统电流模带隙基准源的系统失调、输出电压的下限限制以及电源抑制比低等问题。该带隙基准源采用0.5μm CMOS混合信号工艺进行实现,有效面积450μm×480μm;测试结果表明在3 V电源电压下消耗1.5mW功耗,电源抑制比在1 kHz下为72dB,当温度从-40～85°C变化时,基准电压的有效温度系数为30×10-6V/°C。该带隙基准电路成功应用在一款高速高分辨率模数转换器电路中。     

一种带有软启动的精密CMOS带隙基准设计

提出了一种新颖的带有软启动的高精密CMOS带隙基准电压源。采用UMC的0.6μm2P2M标准CMOS工艺进行设计和仿真,HSPICE模拟表明该电路具有较高的精度和稳定性,带隙基准的输出电压为1.293 V,在1.5 V~4 V电源电压范围内基准随输入电压的最大偏移为0.27 mV,基准的最大静态电流约为19μA;在-40℃~120℃温度范围内,基准随温度的变化约为4.41 mV,产生的偏置电流基本上不受电源电压的影响,而与温度成线性关系;在电源电压为3 V时,基准的总电流约为14.25μA,功耗约为42.74μW;并且基准具有较高的电源抑制比和较低的噪声(小于500 nV/Hz1/2),基准的输出启动时间约为25μs。     

两种新型CMOS带隙基准电路

文章介绍了两种CMOS带隙基准电路.它们在传统带隙基准电路的基础上,采用了低压共源共栅电流镜提供偏置电流,降低了功耗,减小了沟道长度调制效应带来的误差并使电路可以工作在较低的电源电压下;采用运放的输出作为共源共栅电流镜的偏置电压,使基准电压不受电源电压变化的影响.其中一种电路,还通过两个串联二极管的原理提高△VBE,从而减小了运放失调的影响.仿真结果表明,在工艺偏差、电源电压变化±10%以及温度在-20至125℃范围内变化的情况下,两种CMOS带隙基准的输出电压分别是1.228+0.003V和1.215±0.003V,温度系数仅为33.7ppm/℃和34.1ppm/℃;在电源电压分别大于2V和2.8V时,电源电压的变化对这两种基准的输出电压几乎没有影响;在33v电源电压下两个电路的功耗分别小于0.1mW和0.34mW.     

一种高精度BiCMOS电流模带隙基准源

采用Xfab0.35μmBiCMOS工艺设计了一种高电源抑制比（PSRR）、低温漂、输出0.5V的带隙基准源电路。该设计中,电路采用新型电流模带隙基准,解决了传统电流模带隙基准的第三简并态的问题,且实现了较低的基准电压;增加了修调电路,实现了基准电压的微调。利用Cadence软件对其进行仿真验证,其结果显示,当温度在-40～＋120℃范围内变化时,输出基准电压的温度系数为15ppm/℃;电源电压在2～4V范围内变化时,基准电压摆动小于0.06mV;低频下具有-102.6dB的PSRR,40kHz前电源抑制比仍小于-100dB。     

一种高温度性能的CMOS带隙基准源

提出了一种正负温度系数电流产生电路,使用分段线性温度补偿技术用于传统的电流模式基准电路中,改善CMOS带隙基准电路在宽温度范围内的温度漂移.采用0.18μm CMOS混合信号工艺,对该电路进行了设计.在1.8V的电源电压条件下,基准输出电压为0.801 V,温度系数在-40℃-125℃范围内可达到2.7ppm/℃,电源电压从1.5V变化到3.3V的情况下,带隙基准的输入电压调整率为1.2mV/V.     

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.     

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.     

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.     

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.     

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.     

中国建立EB级存储实验室,致力云计算应用(英文)

正With the support of 863 programs,Sugon Information Industry Co.,Ltd.,set up a dawning EB-class storage laboratory to address massive data storage requirements and largescale cloud computing demonstration applications.The Dawning EB-class cloud storage system adopts advanced fault-tolerant architecture,efficient data fault-tolerant algorithms with user authentication and data encryption policies to deal with the"lost""wrong"and"stolen"problems of data for ensuring the reliability and safety of the EB-class storage system in the public network application environments.The Dawning EB-class Storage Laboratory taking advan-