导热型高性能树脂微电子封装材料之一:封装材料的制备

微电子行业迫切需要新一代优异性能的封装材料。采用聚酰亚胺／氮化铝复合材料作为封装材料，可以组合聚酰亚胺和氮化铝的优点，具有高导热、低热胀、低介电、电绝缘等优异的性能，应用于现代微电子领域前景良好。文章讨论了这种封装材料的制各，首先将单体反应物反应得到聚酰亚胺预聚体，然后将预聚体与氮化铝高能球磨混合，最后热压成型。成功制各出一系列聚酰亚胺／氮化铝复合导热型高性能塑料微电子封装材料。     

液晶聚酯与氮化铝复合基板材料的研究

利用模压成型方法制备了氮化铝（ＡＩＮ）和液晶聚酯（ＬＣＰＥ,ＰＥＴ／６０ＰＨＢ）的复合基板材料,研究了影响基板材料导热系数,线膨胀系数,介电性能和力学性能的因素,实验结果表明,在复合材料中ＡＩＮ的用量是影响复合材料上述各种物理性能的关键;对氮化铝粉的处理和改善ＡＩＮ与聚合物之间的两相界面,则是进一步提高复合材料热物理性能和力学性能的重要环节。填加８５％（质量）的ＡＩＮ的液晶聚酯复合基板材料其导热系     

AlN-CNTs/聚酰亚胺复合材料的制备与性能

为了研究氮化铝(AlN)和碳纳米管(CNTs)对聚酰亚胺(PI)的导热、热学、力学性能的协同效应,采用湿法球磨和热压成型法制备了AlN/PI和CNTs-AlN/PI复合材料。利用X射线衍射仪、扫描电子显微镜对复合材料进行了物相分析和断面形貌表征,分别考察了AlN及其与CNTs协同对PI复合材料的导热、热学、力学性能的影响。结果表明,AlN和CNTs在PI基体中分散均匀且接触界面良好,AlN的加入可以显著地提高复合材料的导热性能,且对复合材料的热稳定性和力学性能有一定的提高;固定AlN的含量为10%,加入少量的CNTs可以提高复合材料的导热性能,但对复合材料的力学性能有一定的负面影响。     

颗粒填充型聚合物的导热性能与摩擦磨损性能研究

采用蒙特卡罗可控空间分布算法,生成网链构型的三维代表体积单元(RVE)模型,数值研究了非均匀分布下不同组分氮化铝/石墨/银导热硅脂的导热性能。制备了氮化铝、氮化铝/石墨、氮化铝/石墨/银三种填料体系的导热硅脂,并测试所有样品的热导率和体积电阻率。采用往复摩擦磨损试验机对室温下导热硅脂在钢-钢摩擦副上的载流摩擦磨损性能进行研究。利用扫描电子显微镜(SEM)观察金属表面并利用能谱分析仪(EDS)对表面元素成分进行分析。结果表明:导热填料形貌越丰富,硅脂中的导热网络越致密,氮化铝/石墨/银硅脂的最大热导率可达1.623 W/(m·K),可实现在较少填充量下获得较高热导率;氮化铝/石墨/银有限元模型模拟的结果更贴近实验测量值,可以用来预测球状/片状/棒状颗粒填充导热硅脂的导热性能;氮化铝/石墨/银导热硅脂的载流摩擦磨损性能最优,这归结于其导热性能和导电性能协同减轻电弧对金属表面的侵蚀。     

氮化铝薄膜改善LED散热性能的研究

研究了氮化铝薄膜对LED灯散热情况的影响，并与导热硅脂（Ks609）涂层的散热效果进行了比较，结果表明：导热涂层能加强LED的散热，氮化铝薄膜散热效果优于导热硅脂；对红、白、绿3种颜色LED，相同条件下，散热材料对红色LED的散热效果最好。研究结果为氮化铝薄膜应用于LED散热系统提供了参考数据。     

导热型高性能树脂微电子封装材料之二:封装材料的导热和热膨胀性能

微电子行业迫切需要新一代优异性能的封装材料。采用聚酰亚胺/氮化铝复合材料作为封装材料，可以组合聚酰亚胺和氮化铝的优点，具有高导热、低热胀、低介电、电绝缘等优异的性能，应用于现代微电子领域前景良好。文章讨论了这种封装材料的导热性能和热膨胀性能。PMR聚酰亚胺/氮化铝复合封装材料导热系数随氧化铝的加入量而显著提高，Bruggeman方程最适合于描述该封装材料的导热系数。PMR聚酰亚胺与氮化铝复合后热膨胀系数显著减小。     

高导热云母胶制备工艺研究

采用无机纳米氮化铝粉体填充改性环氧树脂,获得所需的高导热云母胶。针对氮化铝粉体的表面改性、粉体掺杂方式对云母胶导热系数的影响进行了系统分析。经导热系数测试,确定了粉体的表面改性工艺,得到了最佳的粉体分散工艺。     

高导热率及低介电常数的AlN/PI纳米复合薄膜研究

通过将纳米氮化铝加入到原位聚合而成的聚酰亚胺中以提高纳米复合薄膜的导热系数.采用KH550偶联剂对氮化铝粒子表面进行物化处理,以提高有机-无机两相界面的结合力.采用SEM、TGA等对材料的微观结构、热性能等进行了研究.结果显示无机粒子在纳米复合薄膜中分散均匀,并在保持较低的介电性能同时提高了复合材料的热稳定性和导热性能.这样的材料在电子封装材料和印刷线路板中具有很大的应用前景.     

氮化铝覆铜板在空间热场下热学性能的模拟仿真及实验验证

氮化铝(AlN)陶瓷具有高导热、高电阻率、良好的尺寸稳定性以及优异的力学性能等特性, 被认为是新一代高性能陶瓷基板和封装的首选材料。本研究探讨了高性能陶瓷在空间电子系统的应用潜力, 对AlN材料的基础性能进行了分析, 重点分析了AlN陶瓷材料及其覆铜板的热传导性能, 从理论上分析了AlN材料及覆铜板的热特性, 并通过仿真模拟对理论值进行了分析验证, 最后探讨了AlN陶瓷覆铜板在空间热循环模拟环境下的热传导性能。结果表明AlN陶瓷的导热系数高达174.1 W·m ^-1·K ^-1, 覆铜板比纯氮化铝陶瓷具有更高的热扩散系数, 而热特性的仿真结果与理论计算一致。最后空间环境模拟试验表明, AlN材料在温度循环环境下的热传导性能非常稳定。     

导热聚对苯二甲酸丁二醇酯的制备及不同成核剂对其结晶性能的影响

为提高聚对苯二甲酸丁二醇酯(PBT)的导热系数,在PBT基体中添加导热填料氮化铝(AlN)、氮化硼(BN)制备复合导热PBT材料。导热填料的加入使树脂的物理机械性能下降,采用差示量热、X射线衍射等方法研究了不同成核剂对导热PBT结晶性能的影响。结果表明:成核剂的加入改善了导热PBT的结晶性能,同时恢复了其物理机械性能。其中氧化镁起到了明显的成核作用,提高了导热PBT的结晶度、结晶峰峰值温度和熔融焓。     

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.……     

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.     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.     

新闻(英文)

正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to     

Win-Win Cooperation

正The Chinese Premier Li Keqiang's recent trip to the UK has reinforced the China-UK comprehensive strategic partnership;just as the British Prime Minister David Cameron put it,"the relationship is gaining in strength,depth and understanding"after a bucket of business deals being inked worth more than 30 billion US dollars.From the first agreement signing in 2004 to the new agreement of mutual standards recognition and adoption in     

Systematic Approach for Emerging Industry

正A national directory of standards complexes for strategic emerging sectors was recently developed and released jointly by 12governmental departments,namely,SAC,NDRC,MOST,MIIT,MEP,MOA,AQSIQ,State Forest Administration,State Administration of Science and Technology for National Defense,State Oceanic Administration and National Railway Administration.     

Strictest Pollutants Emission Standards

正Four new national standards on air pollutant emission control offi cially issued by the Ministry of Environment Protection(MEP)together with AQSIQ and SAC has been brought into force from July 1,2014.The Emission standard for air pollutants of coal-burning,oil-burning and gasfi red boilers,which is the strictest emission standard historically,will tackle the stubborn pollution problem of boilers and waste incineration in most of China’s regions.     

Instructions to Authors

New Carbon Materials is a bimonthly journal published with the permission of the Ministry of Science and Technology and of the State News and Publication Agency.The journal is sponsored by the Institute of Coal Chemistry,Chinese Academy of Sciences,and is published by Science Press.Aims and Scope     

Progress on Standards Copyright Protection

正Recently,National Copyright Administration of China(NCAC)has rewarded 215 organizations and 179 individuals for their outstanding efforts on investigating standards copyright infringement and piracy in 2013.Hua Jianhua,the Deputy-Director of National Standards Copyright Protection Workgroup Office won a third prize of the national individual award.In 2012,SAC set up the national standards copyright protection working group,and developed policies to crack down standards infringement and piracy behaviors and to strengthen standards copyright protection.