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1.
介绍了高可靠电镀Ni/Au工艺在PTFE微波印制电路上的应用,并分析了氨基磺酸盐镀软镍和亚硫酸盐镀软金工艺的影响因素及提高Ni/Au镀层之间附着力的措施。通过实验及应用证明了与直接镀金工艺相比,在软基材PTFE敷铜箔板上镀Ni/Au工艺能大大提高微波电路的可焊性,高温稳定性和长期可靠性,并且用其所制作的微波器件的高频性能也优于直接镀金工业。 相似文献
2.
本文简要阐述了可靠性管理的概念,在我所技术质量管理的基础上,从产品立项、设计、设计评审、流片、封装、考核到鉴定使用全过程,对ASIC可靠性管理进行了分析和探讨,强调各部门必须保证工作质量,强化可靠性管理,通过管理把高可靠性注入到产品中去。 相似文献
3.
简要分析了白瓷双列直插外壳的失效模式和失效机理,并进行了模拟实验,通过对实验结果的分析,提出对成品微电路进行二次电镀能够提高其外壳的使用可靠性。 相似文献
4.
P. Davies 《Accreditation and quality assurance》1996,1(6):240-246
Laboratory accreditation is becoming increasingly accepted around the world as a means of identifying technically competent
laboratories. It is also being used as a mechanism for the acceptance of test data both nationally and internationally. The
concept and mechanisms of accreditation have been developed over the past 50 years. The first national laboratory accreditation
system appeared in Australia in 1947. This organisation, known as the National Association of Testing Authorities (NATA),
has since taken a leading role in developing accreditation practices that are now used world-wide in evaluating testing, measurement
and calibration laboratories. This paper examines the development of the world's first and largest laboratory accreditation
system, and looks at the difficulties and triumphs in gaining acceptance and recognition by government and industry of the
benefits of laboratory accreditation.
Received: 24 June 1996 Accepted: 25 June 1996 相似文献
5.
无向网络K终端可靠度的分解算法中,包括多边形→链简化在内的等可靠度简化和分解定理结合,可以降低算法的复杂度。本文完善了边随机无向网络和混合随机无向网络的4#,6#,7#型多边形→链简化定理。计算机编程验证了其正确性。 相似文献
6.
7.
本文在测试分析N 理层—隧道氧化层一多晶硅电容(N OP电容)、P衬底一隧道氧化层一多晶硅电容(POP电容)和EEPROM单元隧道氧化层电容(TOP电容)的I-V特性、I-t特性、V-t特性的基础上,对隧道氧化层的击穿特性进行了理论分析,并提出了提高隧道氧化层可靠性的具体措施。 相似文献
8.
This paper presents a theoretical framework about interface states creation rate from Si-H bonds at the Si/SiO2 interface. It includes three mains ways of bond breaking. In the first case, the bond can be broken thanks to the bond ground state rising with an electrical field. In the two others cases, incident carriers will play the main role either if there are very energetic or very numerous but less energetic. This concept allows us physically modeling the reliability of MOSFET transistors, and particularly NBTI permanent part, and Channel Hot Carrier (CHC) to Cold Carrier (CCC) damage. Finally, the translation of these physical models into reliability spice models is discussed. These models pave the way to Design-in Reliability (DiR) approach which seeks to provide a quantitative assessment of reliability - CMOS device reliability in this case - at design stage thereby enabling judicious margins to be taken beforehand. 相似文献
9.
The study of the impact of human activity patterns on network dynamics has attracted a lot of attention in recent years. However, individuals’ knowledge of their own physical states has rarely been incorporated into modeling processes. In real life, for certain infectious processes, infected agents may not have any visible or physical signs and symptoms; therefore, they may believe that they are uninfected even when they have been infected asymptomatically. This infection awareness factor is covered neither in the classical epidemic models such as SIS nor in network propagation studies. In this article, we propose a novel infectious process model that differentiates between the infection awareness states and the physical states of individuals and extend the SIS model to deal with both asymptomatic infection characteristics and human activity patterns. With regards to the latter, we focus particularly on individuals’ testing action, which is to determine whether an individual is infected by an epidemic. The simulation results show that less effort is required in controlling the disease when the transmission probability is either very small or large enough and that Poisson activity patterns are more effective than heavy-tailed patterns in controlling and eliminating asymptomatic infectious diseases due to the long-tail characteristic. 相似文献
10.