一种皮瓦级超低功耗电压基准源

设计了一种皮安级电源电流的高精度电压基准源。采用一种新型的PVT(工艺、电源、温度)补偿技术,在保证超低功耗的同时,有效抑制了PVT变化对电路性能的影响,提高了基准电压的稳定性和精度。基于标准0.18 μm CMOS工艺进行设计,采用Spectre进行仿真。结果表明,在0.9~1.8 V输入电源电压下,输出电压为755.5 mV,线性调整率为4.16×10-6/V,电源抑制比为-95.5 dB @10 Hz,3δ误差为0.11%。在-20 ℃~120 ℃范围内,平均温度系数为1.65×10-5/℃。室温环境下,典型工作电流为347 pA。该电压基准源性能优良,适用于低功耗物联网应用系统。     

一种具有大电流驱动能力的低温漂带隙基准电压源

基于XFAB 0.6 μm CMOS工艺,设计了一种具有大电流驱动能力的低温度系数带隙基准电压源。通过设置不同温度系数的电阻的比值,实现带隙基准的2阶曲率补偿。采用新的电路结构,使基准源具有驱动10 mA以上负载电流的能力。经过Hspice仿真验证,常温基准输出电压为2.496 V,-55 ℃~125 ℃温度范围内的温度系数是3.1×10-6/℃;低频时,电源电压抑制比为-77.6 dB;供电电压在4~6 V范围内,基准输出电压的线性调整率为0.005%/V;负载电流在0~10 mA范围内,基准输出电压波动为219 μV,电流源负载调整率为0.022 mV/mA。     

一种温度系数低于1×10-6/℃的带隙基准电压源

提出了一种温度系数低于1×10-6 /℃的曲率补偿带隙基准电压源。采用正温度系数电压对具有互补温度系数的BJT射-基极电压进行1阶补偿,向BJT射极注入互补温度系数电流,在输出电流中引入曲率正补偿项Tln T,以实现高阶温度补偿。同时,提出了一种新型曲率补偿的低压实现电路。基于标准0.18 μm CMOS工艺进行电路设计。仿真结果表明,在-40 ℃~125 ℃范围内,常压、低压带隙基准电压源的温度系数分别为3.48×10-7 /℃和4.73×10-7 /℃,电源抑制比分别为-73 dB和-60 dB,最大消耗电流分别为22 μA和19 μA。该新型低压曲率补偿带隙基准电压源的工作电压为0.9 V,面积为0.019 8 mm²。     

一种带曲率补偿的高精度带隙基准源设计

基于OKI 0.5 μm BCD工艺,设计了一种带曲率补偿的低温漂带隙基准源。采用Brokaw带隙基准核心结构,引入一个高阶效应的电流,对基准进行补偿。结合基准核心电路产生的无温度系数电压,利用简单的电路实现基准电流源的产生。仿真结果表明,在4.5 V供电电压下,-40 ℃~150 ℃温度范围内,基准电压的波动范围为1.1755~1.17625 V,温漂为3.9 ×10-6/℃,基准电流为3.635 μA,输出基准电流波动仅为2.2 nA,精度较高,低频时电路电源抑制比为-76 dB。     

一种可修调的高精度低温漂带隙基准电压源

设计了一种可修调的高精度、低温漂、高电源电压抑制比的高阶温度补偿带隙基准电压源。在Brokaw型带隙基准电路结构的基础上,采用多晶硅电阻负温度系数补偿技术,可实现2阶曲率温度补偿,减小了基准电压的温漂;设计了电阻修调网络,保证了基准电压的高精度。电路基于标准双极工艺进行设计和制造,测试结果表明:在－55 ℃~125 ℃温度范围内,15 V电源电压下,基准源输出电压为2.5(1±0.24%) V,温度系数为1.2×10－5/℃,低频时的电源电压抑制比为－102 dB,静态电流为1 mA,重载时输出电流能力为10 mA。     

一种4阶曲率补偿低温漂低功耗带隙基准源

基于UMC 0.25 μm BCD工艺,设计了一种4阶曲率补偿的低温漂带隙基准电压源。通过设置正负温度系数相异的电阻的比值,抵消了三极管发射极-基极电压泰勒级数展开后的高阶项,实现了4阶曲率补偿。经过Hspice仿真验证,基准输出电压为1.196 V,-40 ℃~150 ℃温度范围内温度系数达到1.43×10-6/℃;低频时电源抑制比为-70.8 dB,供电电压在1.7~5 V变化时,基准输出电压的线性调整率为0.039%,整体静态电流仅为9.8 μA。     

一种高温段曲率补偿基准电压源的设计

在传统电流型带隙基准源的基础上,设计了一种高温段曲率补偿基准电压源。利用工作在亚阈值区的PMOS晶体管的漏电流与栅源电压的指数关系产生非线性补偿电流,对温度特性曲线的高温段进行补偿。采用0.18 μm 标准CMOS工艺对电路进行设计与仿真,结果显示输出基准电压为600 mV,1 kHz下的电源电压抑制比为-55.5 dB,在-40 ℃~125 ℃温度范围内的温度系数为2.26×10-6/℃。     

一种新型的低功耗指数补偿带隙基准

基于0.18 μm BCD工艺,设计了一种新型的低功耗指数补偿带隙基准。对高温段进行指数补偿,降低温漂;利用预稳压技术,引入负反馈环路以提高基准的电源电压抑制比。经过HSPICE仿真验证,基准输出电压为1.233 V,-15 ℃~145 ℃温度范围内的温度系数为3×10-6/℃;低频时电源电压抑制比为-94 dB,供电电压在2.8~5 V变化时,基准输出电压的线性调整率仅为0.000 5%,当供电电源为2.8 V时,整体静态电流仅为3.8 μA。     

一种新颖的低温漂高电源抑制比带隙基准源

介绍了一种基于0.6 μm BiCMOS工艺的高阶曲率补偿、高电源抑制比的带隙基准源。利用三极管电流增益的温度特性来实现低温度系数,并且不需要额外的电路。采用一种新颖的电压预调整器来实现高电源抑制比。结果表明,该带隙基准源在-40 ℃~120 ℃内的温度系数为2.83×10-6/℃,在低频、100 kHz、1 MHz处的电源抑制比分别为-127 、-98、-67 dB。最低工作电压为1.8 V,在1.8~3 V电源电压范围内的线性调整率为4×10-5/V,功耗为57 μW。     

一种改进型低温度系数带隙基准源电路

在传统带隙基准源的基础上,设计了一种改进型带隙基准源电路,能很好地抑制三极管集电极电流变化对输出的影响,获得很低的温度系数和很高的电源电压抑制比。基于BCD 0.18 μm工艺库,仿真结果表明,当电源电压VIN为4.5 V,温度范围为-40 ℃~140 ℃时,基准源电路的输出电压范围为1.2567~1.2581 V,温度系数为6.3 ×10-6/℃;电源电压在2.5~5 V范围内变化时,基准源电路输出的最大变化仅为1.66×10-4 V,线性调整率为0.006 64 %;低频电源电压抑制比高达97 dB。过温保护电路(OTP)仿真表明,该基准源电路有良好的温度特性,温度不高于140 ℃都可正常工作。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.