中国元器件在线2004年4月份发布新闻要目

中国元器件在线(www.ieechina.com)是中国较早建设的元器件门户网站之一,收集了国内外几乎所有的知名公司与元器件相关的资讯,日平均发布新闻20条,收录了近10万种元器件的技术数据。以下是中国元器件在线2004年4月所发布的部分新闻标题。更多的,更详细的内容敬请访问:www.ieechina.com。中国元器件在线2004年4月份发布新闻要目●业内新闻凌特器件在火星探测器上显示威力安森美半导体加入移动通信行业处理器接口联盟LCD需求暴增元器件企业面临新机遇富士通与Sumitomo合建公司投资2亿生产半导体“2004安捷伦电子测量仪器展”在武汉召开三星…     

元器件采购进入网络时代——“中电网”推出在线采购业务

继今年1月18日中国电子元器件信息交易网(以下简称“中电网”,网址:http://www.ChinaECNet.com)开通之后,在目标是建立全球最大、最有影响力的中文电子元器件门户网的发展过程中,“中电网”迈出了扎扎实实的、也是具有深远意义的一步——正式启动了全球电子元器件在线采购业务。带着想进一步了解“中电网”的背景、发展战略以及“中电网”在线采购特点的目的,本刊记者近日专门采访了“中电网”的高层管理人员。 接受本刊专访的“中电网”高层领     

安富利联合中电网开通在线商店--为中国客户提供电子元器件在线采购平台

全球最大的电子元器件分销商安富利公司(Avnet)与中国领先的电子行业门户网中电网宣布,双方联合开发的安富利在线商店(http://shops．chinaecnet．com/avnet)正式开通。中国的电子元器件用户即日起就可以通过安富利在线商店进行交易。     

ADI在中电网成功举行在线座谈

10月25日上午,中国电子元器件信息交易网(中电网,www.ChinaECNet.com)与著名的美国模拟器件公司(Analog Devices Inc.)合作,成功举办了该公司在中电网上的第一次在线座谈。     

“中国电子元器件信息交易网”的专题在线座谈

“中国电子元器件信息交易网”(中电网,www.chinaecnet.com)自2000年11月起先后为TI、PhiIips、Molex、National Semiconductor、Xicor、Tyco和On Semiconductor公司举办了7期专题在线座谈,收到了良好的效果。专题在线座谈方式所具有的即时互动性,专业覆盖率高以及体现出的跨时空平台的优越性,既使在当前电子元器件行业发     

电子展在线引领效果营销商业模式创新

中国电子展联手电子元件技术网（www．cntronics．com）日前推出一项崭新的B2B电子元器件交易信息平台——电子展在线,帮助网铺更有效地服务客户和降低成本。电子展在线是中国电子第一大电子展的服务延伸,它通过电子元件技术网的平台（www．cntronics．com／CEF）使中国电子展的传统会展服务延伸到电子商务,覆盖了所有电子元器件的交易信息,包括被动元件、分立器件、集成电路、机电元件、线材线束、电路模组等类别。为展商开设网上铺位,连接电子元器件供应商和电子整机制造商之间供求信息。     

Vishay荣获2011中国市场电子元器件领军厂商奖

日前,Vishay Intertechnology宣布,被cntronics.com,中国电子展(CEF)和中国电子商情(CEM)杂志授予"无源元件"类的2011中国市场电子元器件领军厂商奖(CMECMA)。     

电子制造商评估元器件供应商的多个要素分析

日前,中国电子展组委会和中国电子商情杂志社联手电子元件技术网(www.cntronics.com)共同举办的2009中国电子元器件领军厂商评选胜利完成,将于2009年11月11日在上海浦东新国际展览中心举办盛大的颁奖和展示活动。5大领域的16家厂商获得中国市场领军厂商的称号,5家本土厂商获得最具成长性厂商称号。借此机会,中国电子商情和电子元件技术网采访了几家获奖的厂商,从多个要素解析厂商获奖的内在原因。     

在线座谈

中电网与美国ADI公司座谈时间:2009年4月15日上午10:00-12:00在线注册:http://www.ECCN.com/reg中国电子元器件信息交易网(简称中电网)与美国ADI公司(Analog Devices Inc.,简称ADI)合作,将在2009年4月15日上午10:00-12:00在中电网上举办在线座谈。这次在线座谈的主题是"全面理解和高效应用数字电位计"。     

Molex公司在中电网上举办的在线座谈引起巨大反响

2001年3月23日,中国电子元器件信息交易网(简称中电网,www.ChinaECNet.com)与著名的Molex公司合作,成功地举办了该公司在中电网上的第一次在线座谈。这次在线座谈的主题是"Molex公司的连接器在手机上的应用探讨”。在座谈中,中电网先在线播放了Molex公司的讲解资料,讲授内容涉及手机市场的回顾与展望、手机技术发展趋势、连接器在手机上的应用、Molex     

Field-effect transistors based on organic single crystals grown by an improved vapor phase method

High-quality organic single crystals are produced directly onto the substrates using an improved vapor phase method. Unlike the conventional vapor phase methods, the present method is characterized by forming a large-sized crystal to which semiconductor devices can readily be made. The relevant method requires small space of only a 10-cm cube in which a couple of plates are put in close proximity. The crystal growth is carried out nearly at the thermodynamic equilibrium within the narrow space surrounded with the two plates. Thin single crystals of several hundreds of micrometers in size are grown on one of those plates. For the organic materials to be crystallized, we have chosen 1,4-bis(5-phenylthiophen-2-yl)benzene (AC5) and 5,5-diphenyl-2,2′:5′,2″:5″,2:5,2-quinquethiophene (P5T) from among thiophene/phenylene co-oligomers. The resulting crystals are well-defined polygons, each side reflecting the specific crystallographic orientation. In particular, those grown on self-assembled monolayers are exceedingly flat and free from cracks. We have directly fabricated top-contact field-effect transistors on these crystals. The devices exhibit the excellent performance and keep it both in air and in vacuum for a maximum of a hundred days.     

Ab-initio simulation of self-interstitial in germanium

Density functional theory (DFT) with local density approximation including on-site Coulomb interaction (LDA+U) has been used to calculate the formation energy of the neutral and charged self-interstitial in germanium as a function of the Fermi level. The calculations suggest that the self-interstitial in germanium can exist in four different charge states: 1–, and 0 for the 1 1 0 split interstitial, 0, 1+, and 2+ for the tetrahedral position. The 1 1 0 split interstitial acts as an acceptor, while the tetrahedral self-interstitial acts as a double donor. Allowing structural changes of the self-interstitial with the charge state, the existence of a “two-state defect” in low-temperature irradiated p-type Ge can be explained.     

实践案例分享与思考：科学传播如何促进科研

本文分享了在果壳网和科学松鼠会的平台上,科学传播与科学研究相互促进的案例,包括：科学传播促进科学共同体内部跨学科间的交流,科学传播帮助整合用于科研的社会资源,科学传播扩大科研结果的影响力,赢取公众信任,科学传播让观点相互碰撞,相互启发。     

Thermal stress concentration factors for defects in plated-through-vias

Plated-through-vias (PTVs) are subject to thermal stress during soldering and in service. Plating and manufacturing defects in the PTV walls (barrels) can create stress concentrations that frequently become the sites of crack initiation during thermal fatigue. This is of growing concern as processing temperatures increase due to the use of lead-free solders, and boards become thicker generating increased stress as PTV aspect ratios rise, making it more difficult to achieve uniform plating thickness throughout the barrel. Finite element analysis (FEA) has been used to develop correlations that can be used to calculate the stress concentration factors (SCFs) for five typical defects as a function of various geometric parameters. In terms of their severity, the defects were ranked as: (1) rapid thickness reduction (SCF  13), (2) occasional waviness (SCF  4.6), (3) gradual thickness reduction (SCF  4), (4) wicking (SCF  4) and (5) waviness (SCF  3.1). The SCF due to an internal pad and the influence of an external pad-barrel corner crack were also investigated. The maximum stress at the defect is found by multiplying the SCF by the von Mises stress at the mid-plane of the corresponding idealized PTV. The latter can be found using either an analytical model or correlations as a function of the aspect ratio and board-to-barrel thickness ratio that were developed using FEA.     

Enhancing optical properties of nanocrystalline silicon films with air exposure

We report the effect of air exposure and deposition temperatures, T_d, on the optical property of nanocrystalline silicon (nc-Si). The nc-Si thin films were investigated by photoluminescence (PL), optical absorption, X-ray diffraction (XRD), Fourier-transform infrared (FTIR) absorption and Raman scattering. Experimental results show the structural change from an amorphous to a nanocrystalline phase at T_d=80 °C. In addition, it suggests that T_d low condition leads to the increase in the density of SiH-related bonds and a decrease in the average grain size, δ. The oxygen absorption peak increases with the air-exposure time. The PL exhibited two peaks at around 1.75–1.78 and 2.1–2.3 eV. The PL increases and blue shifts consistently with the decrease of δ and increase of oxygen content. The first peak may be related to nanocrystallites in nc-Si films and the origin of another one may be due to defect-related oxygen. Thus, by the plasma-enhanced chemical vapor deposition (PECVD) technique at low T_d, we can produce the nc-Si films with different grain sizes, causing the corresponding luminescent properties. The new method processes advantages of low deposition temperature and effective oxidation of nc-Si on inexpensive substrates, thus making it more suitable for developing low-cost array or flexible nc-Si optoelectronic devices.     

Numerical solutions for orthogonal wavelet filters by Newton method

The wavelet transform has recently generated much interest in applied mathematics, signal processing and image coding. Mallat (1989) used the concept of the function space as a bridge to link the wavelet transform and multiresolution analysis. Daubechies (1990) added regularity conditions to find 2N, 2N10, tap coefficients for orthogonal wavelet filters. Owing to the difficulty of finding their closed solutions for large N a numerical method called the Newton method is proposed. We constructed the orthogonal wavelet filter with 2N-tap coefficients by N linear equations and N nonlinear equations. The 2N-tap, 2N10, coefficients we found are very consistent with those of Daubechies. Also, the method can be used to find the orthogonal wavelet filter with N-tap coefficients for N>10.     

A digital CMOS fuzzy logic controller chip using new fuzzifier and max circuit

The design and simulation of a digital fuzzy logic controller applicable for nonlinear systems based on a new strategy in which analog advantages such as low die area, high speed, and simplicity are added to the total digital system advantages, with unchanged digital system properties, is considered in this paper.For implementing this idea, a new programmable fuzzifier circuit has been designed for a 5-bit digital input signal and membership degree as an analog current with 5-bit resolution in the range of . It has also been presented a new high-accurate simple current-mode circuit for Max block.The controller circuit was implemented in an area less than in , CMOS technology. A controller of two inputs, nine rules, and one output simulated with MATLAB systematically, and the total controller circuit simulated with HSPICE and the Layouts were extracted with Magic. The inference speed of the controller is about .     

A high performance pMOSFET with two-step recessed SiGe-S/D structure for 32 nm node and beyond

A novel SiGe-S/D structure for high performance pMOSFET called two-step recessed SiGe-source/drain (S/D) is developed with careful optimization of recessed SiGe-S/D structure. With this method, hole mobility, short channel effect and S/D resistance in pMOSFET are improved compared with conventional recessed SiGe-S/D structure. To enhance device performance such as drain current drivability, SiGe region has to be closer to channel region. Then, conventional deep SiGe-S/D region with carefully optimized shallow SiGe SDE region showed additional device performance improvement without SCE degradation. As a result, high performance 24 nm gate length pMOSFET was demonstrated with drive current of 451 μA/μm at V_dd of 0.9 V and I_off of 100 nA/μm (552 μA/μm at V_dd of 1.0 V). Furthermore, by combining with V_dd scaling, we indicate the extendability of two-step recessed SiGe-S/D structure down to 15 nm node generation.     

Indium tin oxide-free semi-transparent inverted polymer solar cells using conducting polymer as both bottom and top electrodes

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is investigated as a transparent cathode to replace indium tin oxide (ITO) in inverted polymer solar cells. Increasing the thickness of the PEDOT:PSS electrode leads to a reduction in transparency and sheet resistance which lowers the photocurrent but increases the fill factor of the solar cells. The offset of photocurrent and fill factor as the thickness is increased leads to a saturation of the power conversion efficiency to 3%. These electrodes were applied to flexible substrates showing similar device performance to glass based devices. Cyclic bending test of these flexible polymer electrodes show improved conversion efficiency retention (92%) when compared to flexible ITO based electrodes (50%) after 300 bend cycles. In addition to using PEDOT:PSS as a cathode replacement for ITO in inverted solar cells, its use as a semi-transparent anode replacement to Ag is also examined. Semi-transparent inverted solar cells fabricated with ITO as the cathode and PEDOT:PSS as the top anode electrode were demonstrated showing efficiencies of 2.51% while replacement of both ITO and Ag with PEDOT:PSS as both the cathode and anode show efficiencies of 0.47%.     

Games and Simulation: DS Online's Newest Topic Area

Over the past few years, we've all witnessed the hacker community's growing impact on both the IT industry and academia. Host and network exploitation techniques that used to be discussed in "underground" forums are now featured in book series from No Starch Press, Syngress, and other publishers. Furthermore, they've become standard training for security practitioners - see, for example, the SANS Institute's Security 504: Hacker Techniques, Exploits, and Incident Handling course (http://www.sans.org/training/courses.php). It is now beyond doubt that the hacker community has developed efficient techniques for analyzing, reverse engineering, testing, and modifying software and hardware that challenge their college and graduate-school-educated peers. These techniques have let the community substantially contribute to the state of the art of practical computer security. Many academic researchers recognize that marginalizing the hacker community would be a mistake, and increasing numbers of industry and government security practitioners attend hacker conferences such as DefCon (http://www.defcon.org) and Black Hat (http://www.blackhat.com). In fact, the US Military Academy and the US Naval Academy supported their students' participation in computer-security-related competitions at ShmooCon (http://www.shmoocon.org) and DefCon, respectively.