热释电系数测试系统

对铁电薄膜所具有的铁电、热释电特性进行了研究,在此基础上设计出了热释电系数测试系统。ｐＡ级电流放大器是测试系统的设计重点,而其输入阻抗、运算精度及噪声抑制又是设计关键。简要介绍了测试系统的设计思路、组成及工作原理。用所设计的测试系统对ＰＬＴ薄膜样品进行了测试,测试结果表明,溶胶－凝胶工艺制备的ＰＬＴ薄膜样品的热释电电流平均值为２．１×１０－１１Ａ而对应的热释电系数ｐ为２．５２×１０－８Ｃ／ｃｍ２°Ｃ。     

多层结构铁电薄膜的I—V特性性能的研究

为ＦＲＡＭ、ＦＦＥＴ和ＦＤＭ的实际应用研究，提出了多层结构铁电薄膜的设计思想，实际制备了Ｍ／ＢＩＴ／ｐ－Ｓｉ、Ｍ／ＰＺＴ／ＢＩＴ／ｐ－Ｓｉ、Ｍ／ＢＩＴ／ＰＺＴ／ＢＩＴ／ｐ－Ｓｉ三种结构铁电薄膜，并测量了它们的Ｉ－Ｖ特性曲线。结果表明，夹层结构铁电薄膜Ｍ／ＢＩＴ／ＰＺＴ／ＢＩＴ／ｐ－Ｓｉ漏电流密度Ｊ最小，在５００ｎｍ厚时Ｊ＋（＋３Ｖ）约２．８×１０－１０Ａ／ｍｍ２，Ｊ－（－３Ｖ）约１．２×１０－１２Ａ／ｍｍ２优于单层和双层结构铁电薄膜的结果。     

高度取向ZnO薄膜的介电和光波导特性研究

用溶胶凝胶法在不同的基片上制备了具有高度 ｃ 轴即（００２）取向的 Ｚｎ Ｏ 薄膜,研究了溶剂、稳定剂等对合成的先体溶液的影响。对薄膜的 Ｘ Ｒ Ｄ 分析表明随热处理温度的增加,ｃ 轴取向度增大,并且薄膜的晶粒尺寸在 ３００ ° Ｃ～５００ ° Ｃ 范围内增幅较大。用端面耦合的方法测量了制备在 Ｓｉ Ｏ２／ Ｓｉ（１１１）基片上薄膜的波导损耗,即随热处理温度的增加,波导损耗增大,主要来源于 Ｚｎ Ｏ 薄膜与 Ｓｉ Ｏ２ 的界面及晶粒的散射。制备在 Ｐｔ／ Ｓｉ Ｏ２／ Ｓｉ（１１１）基片上薄膜的相对介电常数为 ７～１３,电阻率则为 １．７×１０４ Ω·ｃｍ ～９．８×１０５ Ω·ｃｍ 。     

激光制备多层薄膜及铁电性能的研究

利用脉冲准分子激光淀积（ＰＬＤ）方法，在Ｓｉ基片上制备了ＢＩＴ／Ｓｉ〔１００〕、ＰＺＴ／ＢＩＴ／Ｓｉ〔１００〕和ＢＩＴ／ＰＺＴ／ＢＩＴ／Ｓｉ〔１００〕铁电薄膜。用ＸＲＤ分析了多层铁电薄膜的晶相结构；用Ｓａｗｙｅｒ－Ｔｏｗｅｒ电路研究了这些单层和多层铁电薄膜的铁电性能。结果表明，单层ＢＩＴ的矫顽场Ｅｃ为４ｋＶ／ｃｍ，剩余极化强度为３．４μＣ／ｃｍ２；ＰＺＴ／ＢＩＴ的矫顽场Ｅｃ为８２ｋＶ／ｃｍ，剩余极化强度Ｐｒ为３６μＣ／ｃｍ２；ＢＩＴ／ＰＺＴ／ＢＩＴ夹层铁电薄膜的矫顽场Ｅｃ为５７ｋＶ／ｃｍ，剩余极化强度Ｐｒ为２９μＣ／ｃｍ２。最后讨论了薄膜的铁电性能与多层结构的关系     

MOD法制备PLZT（8／65／35）薄膜的电性能研究

本文对采用ＭＯＤ法制备的ＰＬＺＴ（８／６５／３５）铁电薄膜的电性能进行了研究。ＭＯＤ法可以在ＩＴＯ／Ｇ，Ｐｔ／Ｔｉ／Ｓｉ和Ｐｔ／ＬＮ基片上制备出具有优良铁电性能的ＰＬＺＴ铁电薄膜，采用Ｐｔ下电极的ＰＬＺＴ薄膜，Ｐｓ〉３２μＣ／ｃｍ＾２，而采用ＩＴＯ电极的也得到了Ｐｓ＝２７μＣ／ｃｍ＾２的好结果。本文还讨论了下电极和基片对薄膜电性能的影响。     

PZT铁电薄膜的制备及电学性能研究

使用硝酸锆作锆源的溶胶－凝胶方法制备ＰＺＴ铁电薄膜。他们的电学性能被测试包括电滞回线，电流Ｉ（ｔ）特性，漏电流，矫顽场疲劳和老化。测到的ＰＺＴ薄膜剩余极化８．２μＣ／ｃｍ~２，矫顽场６８ｋＶ／ｃｍ．簿膜的寿命可超过１０~（１１）周期。     

电极对PZT铁电薄膜性能的影响

用溶胶－凝胶法制备ＰＺＴ铁电薄膜。以Ｐｔ／Ｔｉ／ＳｉＯ２／Ｓｉ为底电极，Ａｕ为上电极，形成金属－铁电薄膜－金属结构的铁电电容器。研究电极对ＰＺＴ铁电薄膜结构和电性能的影响，实验发现，金属Ｔｉ的厚度会影响ＰＺＴ铁电薄膜的结构。界面层的存在使介电系数、自发极化、矫顽电压、漏电流都与薄膜的厚度有关。     

LATGS—PVDF热释电复合薄膜研究

研制了ＬＡＴＧＳ－ＰＶＤＦ热释电复合薄膜，测试分析了膜的介电和热释电性能．制膜过程中加极化电场使复合膜中ＬＡＴＧＳ晶粒的内偏场沿极化场取向，达到既具有好的热释电性又不退极化的目的．用这种复合膜研制的热释电探测器的探测率Ｄ＊（５００Ｋ，１０Ｈｚ）高达１．１２×１０８ｃｍ·Ｈｚ１／２·Ｗ－１．     

Au掺杂TiO2／SiO2薄膜的光学非线性特性研究

采用溶胶－凝胶方法制备了Ａｕ掺杂的ＴｉＯ２／ＳｉＯ２复合薄膜（厚度约为１．０μｍ）。Ｘ－ｒａｙ衍射分析表明，Ａｕ的颗粒镶嵌在ＴｉＯ２／ＳｉＯ２复合薄膜的玻璃网络中。谢乐公式计算给出Ａｕ的颗粒大小约为１０ｎｍ。采用Ｚ－Ｓｃａｎ测量技术得此薄膜的光学非线性折射率为１．０９×１０－７ｅｓｕ。     

SBT铁电薄膜及其脉冲准分子激光制备

采用脉冲准分子激光沉积法在Ｐｔ／Ｔｉ／ＳｉＯ２／Ｓｉ衬底上成功地制备了ＳＢＴ铁电薄膜，发现存在一个最佳沉积衬底温度约为４５０℃。在该温度下沉积的ＳＢＴ薄膜具有较饱和的方形电滞回线，其剩余极化Ｐｒ和矫顽电场Ｅｃ分别为８．４μＣ／ｃｍ２和５７ｋＶ／ｃｍ。     

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-