Known Good Die

Advances in reducing size and increasing functionality of electronics have been due primarily to the shrinking geometries and increasing performance of integrated circuit technologies. Recently, development efforts aimed at reducing size and increasingfunctionality have focused on the first level of the electronicpackage. The result has been the development of multichip packaging,technologies in which bare IC chips are mounted on a single high density substrate that serves to package thechips, as well as interconnect them. A number of benefits accruebecause of multichip packaging, namely, increased chip density,space savings, higher performance, and less weight. Therefore, thesetechnologies are attractive for today's light weight, portable, highperformance electronic equipment and devices.In spite of these benefits, multichip packaging has not shown the kind of explosive growth and expansion that was predicted[1]. A major inhibitor for these technologies has been theavailability of fully tested and conditioned bare die, orknown good die. This paper reviews the issues and technologies associated with test and burn-in of bareor minimally packaged IC products.     

基于PPCZ模型的KGD水力压裂数值模拟

Pore pressure cohesive zone模型以Barenblatt裂尖黏聚力模型为基础,考虑了裂尖断裂过程区对裂缝扩展的影响,对模拟水力裂缝扩展问题具有一定优势。采用该数值模型对KGD水力压裂问题进行研究,验证了模型模拟KGD水力裂缝的能力,分析了裂尖断裂过程区及流体黏度μ对裂缝扩展的影响,揭示了排量Q_0、黏度μ和注入时间t三者之间的联系。研究表明:(1)断裂过程区对压裂结果有较大影响,其内在原因是:随着裂缝刚度K_(nn)的变化,缝内流体不同程度地渗透到裂尖断裂过程区,改变了裂尖断裂的难易程度和缝内流体压力的响应行为;(2)流体黏度增加导致缝内净压力和缝宽的增加、缝长的减小;(3)对于两种主控型水力裂缝,排量Q0、黏度μ和注入时间t之间存在着内在联系:μQ_0不变、Q_0t不变情况下,最终可得相同的缝压、缝宽和缝长值;(4)相比于弹性状态,弹塑性状态下的岩体需要更高的缝内净压力,才能使得岩体开裂扩展。数值模型具有模拟不同类型水力压裂的能力。     

KGD技术发展与挑战

军用和民用电子系统中模块化和小型化发展的迫切需求使裸芯片在国内有着广泛的用途和市场，尤其是在军用HIC和MCM应用领域，裸芯片质量和可靠性保证一直是人们关注的热点，本文论述了国外KGD技术发展现状，以及国内发展KGD技术面临的机遇与挑战，论述了已知良好芯片（KGD）保证的主要技术要求，重点介绍了KGD夹具技术和工艺流程，为国内KGD技术的发展提供了技术指导。     

裸芯片老化技术评价

老化可以筛选出裸芯片的潜在缺陷并因此改善产品的外在质量与可靠性.同时,老化也是非常耗时与耗费人力的.如果对产品的可靠性水平要求较低,要想低成本获得已知良好芯片(KGD),一般是不采用老化程序,但如果想获得高可靠KGD,一定程度的老化是必不可少的.本文将介绍老化的三种通用方法并进行了比较分析.     

KGD质量和可靠性保障技术

通过裸芯片可靠性保障技术研究,在国内形成了一部完整的已知良好芯片(KGD)质量与司靠性保证程序,建立了从裸芯片到KGD的质量与可靠性保证系统,确立了裸芯片测试、老化和评价技术,实现了工作温度为-55～ 125℃的裸芯片静态、动态工作频率小于100MHz的测试和工作频率小于3MHz的1 25℃动态老化筛选,可保障裸芯片在技术指标和可靠性指标上达到封装成品的等级要求.     

确好芯片KGD及其应用

本文介绍了国际上确好芯片KGD技术的研发现状,以及在高密度多芯片封装中的应用。     

Design-For-Test in a Multiple Substrate Multichip Module

This paper highlights the development and effectiveness of a multichip module (MCM) Design-For-Testability methodology for an application intended for use in a fully electronic active matrix LCD flight instrument. MCM test issues discussed include Design-For-Testability, substratetest, Known-Good Die (KGD) and module level test.The design incorporates IEEE 1149.1 and Built-In-Self-Test features. Bare die pretest is accomplished with a Ball Grid Array (BGA) chip carrierapproach.The hardware consists of a mature digital design comprised of application specific and industry standard integrated circuits.     

崭露头角的系统封装

文章概述了系统封装（SIP）的概念、特点和问题点。着重指出，系统封装（SIP）是由MCM和MCP深入发展和改革而发展起来的。系统封装（SIP）技术是电子产品的组装技术和走向微小型化的未来。     

确好芯片商业化的关键问题

基于老化筛选技术的确好芯片KGD是现行多芯片封装结构中的关键芯片,具有封装成本低、可靠性高、体积小、易封装集成等优点,其应用前景广泛,如多芯片组件、多芯片封装、系统封装、功率系统封装、微系统封装、堆叠封装、混合集成电路等。文章对KGD技术做了分类总结,综述了近几年KGD技术的研发进展,指出KGD进一步发展的商业化关键问题。     

A review of methods of low alcohol and alcohol-free beer production

The increasing interest of consumers in health and alcohol abuse issues motivates breweries to expand the assortment of products with low alcohol content. The goal of producing beers with low alcohol content can be achieved by two main strategies; namely by gentle removal of alcohol from regular beer and by limited ethanol formation during the beer fermentation. Within these two basic strategies, there are a number of techniques that vary in performance, efficiency and usability. This paper presents an overview and comparison of these techniques and provides an evaluation of sensorial properties of low-alcohol and an alcohol-free beer produced as well as suggests possibilities for their additional improvement.