InAlAs／InGaAs MSM光电探测器

采用ＧＳＭＢＥ方法及典型的器件工艺制成了用ＩｎＡｌＡｓ作为肖特基势垒增强材料的高性能ＩｎＡｌＡｓ／ＩｎＧａＡｓ／ＩｎＰ ＭＳＭ光电探测器。用自制的测试系统对器件的直流和瞬态特性进行了测试，测试结果表明，器件的击穿电压大于３０Ｖ，在１０Ｖ偏压下暗电流小于２０ｎＡ，对应的暗电流密度为３ｐａ／μｍ＾２，优于已有文献的报导。     

InGaAsP／InP PFBH激光器

采用Ｎ－ＩｎＰ衬底研制ＩｎＧａＡｓＰ／ＩｎＰ激光器和ＤＦＢ激光器在国内已报导过多次，本文介绍用Ｐ－ＩｎＰ衬底研制ＩｎＧａＡｓＰ／ＩｎＰ平面埋层异质结构激光器和ＤＦＢ－ＰＦＢＨ激光器，同时利用晶体生长和晶向的依赖关系，改进埋区的结构，使器件最高激射温度大于１００℃。     

0.1-0.3μmX射线光刻技术在GaAs器件制作中的应用

对同步辐射Ｘ射线光刻及在ＧａＡｓ ＰＨＥＭＴ器件制作中的应用进行了研究,并制作出栅长０．１５μｍ的ＡｌＧａＡｓ／ＩｎＧａＡｓ／ＧａＡｓ ＰＨＥＭＴ晶体管。研究结果表明,Ｘ射线光刻在肃离图形册结构制作工艺中具有极好的光刻图形质量,在混合光刻工艺中,抑止ＧａＡｓ合金点的形成是取得良好的对准标记的关键。     

电子束蒸镀半导体发光二极管的减反射膜

用电子束蒸发设备，制备了用于光纤通信等中的ＧａＡｓ和ＩｎＰ系列双异质结红外发光二级管的减反射介质膜。测量结果表明，对发光波长为０．８５μｍ和０．９０μｍ的ＧａＡｌＡｓ／ＧａＡｓ发光二级管，蒸镀四分之一波长厚的Ａｌ２Ｏ３减反射膜，输出光功率在５０ｍＡ和１００ｍＡ电流注入下，可增加２５￣３５％，最大可增加５０％。但对于１．３μｍ波长的ＩｎＧａＡｓＰ／ＩｎＰ型红外发光二极管，用ＺｒＯ２作减反射膜，比用Ａ     

InGaAsP/InP有源时分光子交换器件

自行设计并研制成功了两种有源时分光子交换器件：ＩｎＧａＡｓＰ／ＩｎＰ ＥＭＰＢＨ双稳激光器ＩｎＧａＡｓＰ／ＩｎＰ ＭＱＷ ＤＣＰＢＨ双稳激光器，对这两种器件的部分性能作了简要报道。     

高温退火对InGaAsP/InP双异质结光弹波导结构的影响

光弹效应光电子器件是一种适合光电子集成的新颖平面型器件结构。ＩｎＧａＡｓＰ／ＩｎＰ双异质结外延片在直流负偏压１２０Ｖ作用下,利用射频溅射和光刻肃离技术在样品表面沉积１１０ｎｍ厚的Ｗ０．９５Ｎｉ０．０５金属薄膜应变条。在Ｗ０．９５￣Ｎｉ０．０５金属薄膜应变条下的半导体内形成了对ＩｎＧａＡｓＰ／ＩｎＰ双异质结构侧向光具有良好限制作用的光弹波导结构。Ｗ０．９５Ｎｉ０．０５金属薄膜及由其形成的光弹波导器件     

国产金属有机化合物TMGa,TMAl,TMIn和TMSb的MOVPE鉴定

利用我们研制的常压ＭＯＶＰＥ设备对国产ＴＭＧａ、ＴＭＡｌ、ＴＭＩｎ和ＴＭＳｂ进行了鉴定，为此分别生长了ＧａＡｓ、ＡｌＧａＡｓ、ＩｎＰ、ＧａＳｂ外延层和ＧａＡｓ／ＡｌＡｓ、ＧａＳｂ／ＩｎＧａＳｂ超晶格和ＧａＡｓ／ＡｌＧａＡｓ量子阱结构。表征材料纯度的７７Ｋ载流予迁移率分别达到ＧａＡｓ：μ＿ｎ＝５６６００ｃｍ￣２／Ｖ·ｓ，Ａｌ＿（０．２５）Ｇａ＿（０．７５）Ａｓ：μ＿ｎ＝５１６０ｃｍ￣２／Ｖ·ｓ，ＩｎＰ：μ＿ｎ＝６５３００ｃｍ￣２／Ｖ·ｓ，ＧａＳｂ：μ＿ｐ＝５０７６ｃｍ￣２／Ｖ·ｓ。由１０个周期的ＧａＡｓ／ＡｌＡｓ超晶格结构组成的可见光区布拉格反射器已观测到很好的反射光谱和双晶Ｘ射线回摆曲线上高达±２０级的卫星峰。ＧａＡｓ／Ａｌ＿（０．３５）Ｇａ＿（０．６５）Ａｓ量子阱最小阱宽为１０，在ｌｉＫ下由量子尺寸效应导致的光致发光峰能量移动为３９０ｍｅＶ，其线宽为１２ｍｅＶ。这些结果表明上述金属有机化合物已达到较高质量。     

Ge／Pd／n—GaAs低阻欧姆接触的SIMS分析

采用Ｇｅ／Ｐｄ／ＧａＡｓ结构和快速热退火在ｎ－ＧａＡｓ上形成了低阻欧姆接触，利用二次离子质谱技术揭示和讨论了低欧姆接触形成的机理。比较了采用Ｘ＾＋和ＧｓＸ＾＋信号检测的Ｇｅ，Ｐｄ，Ｇａ和Ａｓ的深度分布。结果表明采用ＣｓＸ＾＋可以提供更准确的结果和成分信息。     

单电源低电压InGaP/InGaAsPHEMT低噪声单片放大器

制备了增强型ＩｎＧａＰ／ＩｎＧａＡｓ ＰＨＥＭＴ器件结构、阈值控制以及单电源低电压低噪声单片放大器。获得了阈值电压接近０Ｖ的增强型ＩｎＧａＰ／ＩｎＧａＡｓ ＰＨＥＭＴ器件,并在此基础上设计制作了可在１．５￣３Ｖ低电压和单电源下工作的２．５ＧＨｚ低噪声单片放大器。同时对该电路性能的进一步提高进行了模拟分析。     

国家光电子工艺中心GaAs基Ga(In)NAs研制取得进展

ＧａＡｓ基Ｇａ（Ｉｎ）ＮＡｓ新型材料及器件是当前光电子领域新兴的前沿性热门课题,正在引起世界上广泛的关注和研究。它突破了传统的长波长光纤通信用材料ＧａＩｎＡｓＰ／ＩｎＰ系的局限性,大幅度地提高了光通信用光源的温度稳定性,可以实现长寿命、无需制冷、大温...     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Mechanism Study on the Wear of CrAlTiN Coated High-Speed Steel Twist Drills Under Dry Cutting Conditions

As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.     

Structural Characteristics of TiO2 Ceramic Coating by Micro-Plasma Oxidation

TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.