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1.
《今日电子》2007,(9):64-64
这种全球最薄的加速计MMA7450L采用0.8mm的塑料矩栅阵列(LGA)封装,体积比以前的产品小77%。MMA7450L是为了简化微处理器和微控制器(MCU)的集成而设计的。MMA7450L可以在12C和SPI界面总线上通信,数字输出功能可简化与MCU或微处理器的通信。它消除了对专用模数转换器的需要,使传感器可以和其他器件共享界面,  相似文献   

2.
本文研究一种“反程序”辐射加固工艺,将所有的高温处理过程放在栅氧化之前,并使栅氧化后续工艺低温化,在此基础上,采用“反程序”辐射加固工艺研制出的IGBT加固器件,其抗总剂量辐射性能远远优于采用常规工艺制造出的IGBT器件。对于栅氧化层厚度为70nm的加固器件,在VGS=十10V(直流和脉冲)、VGS=OV等不同栅偏量下,辐射剂量达到IX10~3(Gy(St))时,阈值电压的漂移量小于一1.OV,跨导变化小于10%。采用此工艺,预计抗总剂量辐射能力可达到10~4Gy(Si)以上。  相似文献   

3.
超声波-酶法提取菊花中总黄酮工艺优化   总被引:1,自引:0,他引:1  
目的:优化超声波-酶法提取菊花中总黄酮的工艺。方法:考察不同的影响因素,采用L9(3^4)正交设计优化提取工艺。以芦丁为对照品,以紫外分光光度计分析其提取率。结果:乙醇浓度具有显著性影响,超声波-酶法提取杭菊中总黄酮最佳条件为乙醇浓度为70%,酶添加量为0.4%,在55℃下酶解超声60+20min,其总黄酮得率为6.40%。结论:本工艺简单可行、高效快速,得率比酶解法提高了19.9%。  相似文献   

4.
采用提拉法生长了Yb掺杂原子数分数为0.5%的Yb:Y3Al5O12。(Yb2YAG)晶体,对晶体的吸收光谱和荧光光谱进行了分析。与Yb掺杂原子数分数为5%的Yb:YAG晶体进行了对比,得出采用940nm激光二极管(LD)抽运晶体最为合适。原子数分数为0.5%的Yb:YAG晶体相对于原子数分数为5%的Yb:YAG晶体白吸收效应的影响要小。测量了原子数分数为0.5%的Yb:YAG晶体的荧光寿命为0.95ms,与理论值很接近。因此采用原子数分数为0.5%的Yb:YAG晶体作为激光工作物质将有利于高效、小型集成化的固体激光器的发展。  相似文献   

5.
运用不同的液相外延(LPE)生长工艺,制备了两种结构的AlxGa1-xAs/GaAs太阳电池,并结合透射电子显微镜(TEM)等技术分析了外延工艺对器件性能的影响。结果表明,与过冷生长技术相比,回熔工艺对衬底质量的要求不严格,且能形成有利于光生少子被收集的带隙结构。在工艺优化的情况下,我们所获得太阳电池的全面积转换效率在AM0,1sun条件下为18.78%(0.72cm2),在AM1.5,lsun条件下为23.17%。  相似文献   

6.
基于过采样技术的∑-△ A/D转换器的设计   总被引:1,自引:0,他引:1  
采用基于过采样的∑-△调制技术,设计音频A/D转换器,对量化噪声进行有效的整形,提高了分辨率和带内信噪比(SNR)。对设计进行了详细分析,并给出了有关的电路结构和仿真结果。芯片已采用TSMC 0.18μm CMOS工艺流片成功,在工作频率5.6448 MHz时,该A/D转换器的动态范围达101dB,信噪比为98.2dB,总谐波失真达0.0016%。  相似文献   

7.
报道了采用欠饱和溶液的回熔—再生长液相外延(LPE)方法制备高效AIxGa1-xAs/GaAs异质结构太阳电池的工艺。研究表明,与传统的过冷生长技术相比,回熔工艺对衬底质量的要求不严格,且能形成有利于光生少子被收集的带隙结构。在工艺优化的情况下,获得大阳电池的全面积转换效率在AM0,1sun的测试条件下为18.78%(0.72cm2),在AM1.5,1sun下为23.17%。  相似文献   

8.
马鹏飞  刘大军  周奋国 《红外与激光工程》2020,49(1):0107001-0107001(8)
通过共价键合将二氨基二枯丁苯氧基氯代铟酞菁(Pc)与羧基化氧化石墨烯(GO-COOH)键合在一起,得到二氨基二枯丁苯氧基氯代铟酞菁-氧化石墨烯键合产物(Pc-GO-COOH),并以键合产物为原料反应得到引发剂。以甲基丙烯酸甲酯(MMA)为聚合反应单体,通过原子转移自由基聚合(ATRP)反应得到四种不同分子量的聚合物样品。采用凝胶渗透色谱(GPC)对聚合物分子量分布测试,结果表明,所制备的聚合物的分子量分布范围较窄,聚合反应具有良好的可控性。采用Z-扫描方法对聚合物样品溶液进行的三阶非线性测试结果表明,所制备的聚合物具有优良的三阶非线性光学性质,且当聚合物的分子量分别为9 063和12 196时,三阶非线性极化率值分别为8.1×10-11、2.1×10-11 esu。同时对聚合物样品的光限幅性能测试结果表明,两种样品的有效激发态与基态吸收截面比分别为2.69和2.20,具有较好的光限幅能力,具有较大的应用前景。  相似文献   

9.
本文主要介绍1um双阱双层金属布线硅栅CMOS专用集成电路制造中采用先进的反应离子刻蚀技术,对多种材料如LPCVD、Si3N4、PECVESi3N4、热SiO2、PEVEDSiO2、PSG、BPSG、多晶硅和Al-Si(1.0%)-Cu(0.5%)合金等进行高选择比的,各向异性刻蚀的工艺条件及其结果。获得上述各种材料刻蚀后临界尺寸(CD)总损失<0.08um的优良结果。此外还分析讨论了被选择的刻蚀  相似文献   

10.
利用Z扫描技术,分别测量了五种C60聚氨酯胺薄膜(C60含量分别为0%、0.16%、0.30%、0.42%、0.52%,厚度均为0.3mm)的非线性光学吸收系数和折射系数,并研究了该薄膜的光限幅特性。实验表明:随着样品中C60的含量由0增加到0.52%,薄膜的透射率可由70%逐渐减小到10%,且透射光功率可限制在25mJ/cm^2以下。薄膜的透射率或透射功率可以随C60含量不同而改变,即薄膜的光限幅性能可以通过调节C60含量的方式加以控制。最后,基于C60分子的五能级模型,采用激发态吸收(反饱和吸收)物理机理解释了薄膜的非线性光学特性及光限幅性能。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

18.
A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.  相似文献   

19.
It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.  相似文献   

20.
Call for Papers     
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks  相似文献   

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