碲镉汞小晶片缺陷的同步辐射形貌相分析

在北京正负电子对撞机国家实验室，用同步辐射拍摄了制备长波光导多元碲镉汞红外探测器的小晶片（面积小于１ｍｍ２）的高分辨率白光形貌相。实验结果表明：在碲镉汞小晶片中存在相当多的晶体缺陷，如亚晶界和晶格畸变区等。这些缺陷的存在说明样品受到较强的应力作用，样品晶格的完整性实际上反映了碲镉汞晶体生长和器件制备技术的应力控制水平。根据晶格的畸变模型，讨论了多元线列器件的性能与碲镉汞材料缺陷的关系。     

CdTe/ZnS双层钝化碲镉汞长波探测器制备的研究

开展了CdTe/ZnS双层钝化碲镉汞长波探测器制备的研究。CdTe钝化膜经退火热处理后,可实现CdTe/MCT界面的互扩散,并改善CdTe钝化膜的质量。通过全湿法腐蚀方法完成了金属化开口,制备了长波碲镉汞600×18@15 μm规格线列和640×512@15 μm规格面阵。线列I-V测试表明:CdTe/ZnS双层钝化膜能有效地减少长波碲镉汞器件的表面漏电流,器件的反向结特性良好。面阵在77K测试:NETD 26.7 mK,有效像元率95.4%,并对室温目标进行了凝视成像。测试过程出现了4%左右由噪声引起的零散盲元,是由芯片面阵局部钝化失效引起的,表明钝化膜沉积工艺及芯片加工工艺尚有改进的空间。     

碲镉汞光伏和光导焦平面阵列

将基于光电二极管和光电导体的碲镉汞(HgCdTe)红外焦平面阵列加以比较,包括两类探测器的读出结构、各种结构的信噪比(SNR)分析、以及耦合器件的噪声要求。讨论了线列光导红外焦平面阵列的可行性。介绍了这种新型红外焦平面阵列的重要性。     

光导型碲镉汞探测器的氢化研究

为了提高碲镉汞红外探测器的性能,对ZnS钝化的碲镉汞光导型探测器进行了氢化处理研究,发现处理效果与氢等离子体密度和ZnS钝化层的厚度密切相关。对于ZnS层厚度固定的器件,通过改变氢等离子体密度发现低等离子体密度条件氢化处理更有利于提高器件的性能,表现在处理后器件响应信号提高且噪声下降,从光谱响应上表现为器件短波方向的响应抬高;对于同样的氢化处理条件,通过改变ZnS钝化层的厚度,发现具有较大厚度ZnS层的器件的氢化效果更好。SIMS测试发现氢化过程中氢离子可以穿过ZnS层到达ZnS与碲镉汞的界面处,分析认为氢离子对界面态起到了钝化作用,降低了界面态密度,提高了器件的性能。     

180元长波碲镉汞线列光导探测器研制

本文报道了长波180元碲镉汞线列光导探测器的初步研制结果,较为详细地介绍了各步探测器制造工艺以及探测器性能的测试结果。最终得到的拼接和单片180元线列器件,其平均峰值探测率D_(xp)~*达2.0×10~(10)cmHz~(1/2)W~(-1),电串音小于5％,功耗小于150mW。     

ICP刻蚀气压对碲镉汞电学性能的影响

研究了利用ICP(Inductively Coupled Plasma)干法刻蚀工艺制备长波碲镉汞光导器件过程中刻蚀气体压强对材料电学参数的影响.发现增大气体压强会导致材料的电学性能衰退,表现为材料的载流子浓度增加、迁移率降低以及电阻率增加.分析认为增大的压强使得材料内部产生了更多的填隙Hg离子,增强了载流子受到的电离杂质散射作用;同时材料内部也产生了更多的缺陷,极化声子散射作用也因此加强.由此解释了在流片过程中出现的某一批次碲镉汞光导器件性能的恶化是该批次器件ICP刻蚀工艺中的气压参数增加所致.     

高频碲镉汞探测器的频响特性分析

本文通过器件频响特性测试结果的分析,证实了离子注入成结工艺、器件的高频结构和器件上加负偏压等是获得高频碲镉汞探测器的有效方法。对法国碲镉汞器件的响应频率的测试结果表明,我所研制的高频碲镉汞器件在频率响应方面同法国SAT的碲镉汞器件具有相同水平。     

长波多元线列光导碲镉汞红外探测器实用化组件

本文报导探测器／微杜瓦，１．７５Ｗ／８０Ｋ分置式斯特林制冷机和大动态，低频，低噪音，低源阻集成前置放大器组成的全国产化工程化１６０元双排线列光导碲镉汞红外探测器组件和分置式斯特林制冷机制的１２０元单排线列光导碲镉汞红外探测器组件性能；简述组件芯片制造工艺，组件中探测器芯片，微杜瓦，网络电阻排，吸气剂，测温二极管和微型连接器间的组装技术；介绍组件机械耦合技术和总体联调技术。     

小型多元光导碲镉汞线列红外探测器组件

文章介绍了小型实用化长波光导碲镉汞线列红外探测器组件在华北光电技术研究所的发展近况，其制造技术和性能均得到显著的提高。     

8～14μm单元光导碲镉汞红外探测器

光导碲镉汞红外探测器探测率高,响应率大,响应时间快,七十年代为先进国家推广使用,尤其是空间技术和特殊军事应用上。我们研制的8～14μm玻璃结构和金属结构光导碲镉汞器件曾由国内用户应用于美国HRC红外多谱扫描系统,用户认为其性能与SBRC公司相当;用在中科院物理所研制的紫外-红外平面扫描干涉仪中;效果很好;为高能物理所激光加速原理试验提供了一种探测光场的新方法;北京大学利用该器件在研究“锑化     

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-