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1.
Bi2O3过量对熔盐法制备Bi4Ti3O12粉体的影响 总被引:1,自引:0,他引:1
以NaCl-KCl熔盐法制备了各向异性的Bi4Ti3O12粉体,研究了w(Bi2O3过量)对粉体的影响,优化了制备Bi4Ti3O12粉体的工艺参数。结果表明:w(Bi2O3过量)为7.5%,1100℃烧结2h所得到的Bi4Ti3O12粉体微观形貌最佳,并探讨了Bi4Ti3O12粉体在熔盐中的生长机理。 相似文献
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以水热合成的 Bi3.15Nd0.85Ti3O12(BNdT)纳米颗粒为原料,用熔盐法合成了 BNdT 微米薄片,用 X 射线衍射和透射电镜研究了微米薄片的显微结构,讨论了片状结构的生长机理,并分析了微米薄片的紫外-可见光吸收性能。结果表明:合成的微米薄片是单晶的层状钙钛矿型结构,横向尺寸为 0.2~2.0 μm,光学带隙为 3.12 eV;随反应温度的升高和反应时间的延长,BNdT 微米片横向尺寸逐渐增大;随熔盐含量增加,晶粒尺寸几乎无变化;BNdT晶体结构的大各向异性使其容易形成片状结构。 相似文献
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采用固相烧结法制备了不同掺La量、不同烧结工艺的铋层化合物 Bi4-xLaxTi3O12(x=0,0.25,0.5,0.75,1)介电陶瓷。利用宽频LCR数字电桥和XRD、 SEM分析了Bi4-xLaxTi3O12介电陶瓷的晶相和微观结构对其介电性能的影响。研究表明,1050℃烧结温度保温4h的Bi3.5La0.5Ti3O12介电陶瓷,致密性好、晶粒均匀、具有良好的综合介电性能。 相似文献
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采用熔盐法制备了各向异性生长的SrBi4Ti4O15粉体,研究了工艺参数对晶粒形貌和尺寸的影响。发现煅烧温度、盐的种类和盐的用量显著影响晶粒的形貌和尺寸。晶粒平均尺寸随着温度升高而逐渐增大,由不规则片状向圆片状发育。随着盐用量的增加,晶粒平均尺寸先增大后减小,且在硫酸盐中,晶粒尺寸明显大于相同条件下盐酸盐中的尺寸。和固相法相比,熔盐法合成的粉体具有(00l)择优生长的优点。通过调整工艺参数可以控制晶粒的形貌和尺寸,制备各向异性生长的SrBi4Ti4O15粉体。 相似文献
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熔盐法合成钛酸铋钾陶瓷粉体 总被引:1,自引:0,他引:1
以K2CO3,Bi2O3和TiO2为反应物,KCl为熔盐,通过熔盐法在600℃成功合成纯钙钛矿结构K0.5Bi0.5TiO3(KBT)无铅陶瓷粉体。探寻了制备过程中影响粉体颗粒大小和形貌的工艺参数,并对影响机理进行了探讨。结果表明,与传统固相法相比,熔盐法合成温度显著降低且颗粒平均粒径明显减小。固相法合成的粉体平均粒径为115nm,KCl含量5%和20%的熔盐法合成粉体平均粒径为78nm和67nm。此外,实验发现随着熔盐量的增加,易合成各向异性的棒状粉体。 相似文献
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采用传统电子陶瓷制备工艺制备(1–y)(Na0.5Bi0.5)TiO3-yBa(ZrxTi1–x)O3无铅压电陶瓷,获得了d33高达185pC/N的0.94(Na0.5Bi0.5)TiO3-0.06Ba(Zr0.055Ti0.945)O3压电陶瓷。对Bi的挥发进行了补偿,添加过量Bi2O3(摩尔分数z=0.08)的钛酸铋钠基压电陶瓷,d33高达218pC/N。研究了Mn掺杂对钛酸铋钠基陶瓷压电、介电性能和损耗的影响,获得了高性能的无铅压电陶瓷,其中d33为214pC/N,kt为0.44,k33为0.52。 相似文献
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(Bi4-x,Lax)Ti3O12铁电陶瓷性能研究 总被引:2,自引:0,他引:2
采用溶胶-凝胶(Sol-Gel)技术制备了(Bi4-x,Lax)Ti3O12(BLT)干凝胶粉体,并用此粉体制备了陶瓷。利用XRD、SEM等手段分析表征了陶瓷的结构、表面形貌及介电性能。结果表明,采用本文工艺技术制备的陶瓷为类钙钛矿结构,表面致密,陶瓷的极化场强约为4.5kV/mm;BLT陶瓷介电性能为:介电常数ε=425(1kHz),介电损耗tanδ=0.05(1kHz)。掺杂量的研究表明,当x≥0.4时,La的引入对介电常数和介电损耗有较大的影响,即使介电常数升高,介电损耗降低。 相似文献
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采用常规固相合成工艺研究了添加剂Bi2O3、ZnO等对(Zr0.8Sn0.2)TiO4的烧结性能、微观结构和微波介电性能的影响.结果表明,陶瓷的烧结温度随着Bi2O3含量的增大而降低,而陶瓷的最大烧结密度随着Bi2O3的增大而增大;当w(Bi2O3)>3%时,其烧结可降低至1175℃;各种材料配方均能烧结出致密的陶瓷.陶瓷的介电常数随着Bi2O3含量的增大而略有增大,但增加幅度较小;而材料的介电损耗则随Bi2O3含量的增大而增加,且增大幅度较大.当w(ZnO)=1%、w(Bi2O3)=3%时,可在1190℃获得致密的陶瓷,在测试频率1 MHz下,介电常数约41,介电损耗为1.5×10-4,其综合微波介电性能最佳. 相似文献
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用熔盐法制备了片状 Bi4Ti3O12模板,由 Bi4Ti3O12片状前驱体制备了 Bi0.5Na0.5TiO3(BNT)模板,由模板晶粒生长法制备了织构化0.91Bi0.5Na0.5TiO3-0.06BaTiO3-0.03K0.5Na0.5NbO3陶瓷。研究了 Bi4Ti3O12以及Bi0.5Na0.5TiO3两种模板及模板含量对Bi0.5Na0.5TiO3无铅压电体系织构化的影响及织构化陶瓷的压电性能。结果表明Bi0.5Na0.5TiO3模板比Bi4Ti3O12模板更适合用于此体系的织构化,并且,在加入质量分数15%的Bi0.5Na0.5TiO3模板时 Bi0.5Na0.5TiO3陶瓷取向度达到87.3%。质量分数5%的 BNT 模板织构化的陶瓷在6×103 V/mm 电场下应变达到0.226%,相较于随机取向陶瓷提高了48.7%。 相似文献
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Michael Reilly 《半导体技术》2004,29(12)
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
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Thomas M.Trexler 《半导体技术》2004,29(5)
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
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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
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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
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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
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Qi-jiang Ran Pei-de Han Yu-jun Quan Li-peng Gao Fan-ping Zeng Chun-hua Zhao 《光电子快报》2008,4(4):239-242
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
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Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers
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
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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
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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
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《中国通信》2014,(7)
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