共查询到18条相似文献,搜索用时 78 毫秒
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多层板内层在制程中受到多种因素的影响,内层尺寸产生相应的变化。本文分别就内层图形、半固化粘结片、芯片的厚度和加工工艺对内层尺寸产生的影响进行测量与分析,为PCB多层板的工程制作提供准确的菲林补偿比例,研究提高制程中对位精度的试验方法。 相似文献
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多层板在生产制造过程中,其外形尺寸会因内层基板的尺寸收缩或多或少地发生变化,并因此影响层压后各内层间的偏位,直接影响到多层板的量产。这在多层板制造厂家中不但要引起注意,而且须寻找一个切实有效的,符合各自生产条件的改善补偿方案。下面就内层基板在层压过程中尺寸变化的机理,变化的量度及工程补偿措施作一简要阐述,并将我司在生产过程中总结的经验参数提供给大家参考。 相似文献
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1 前言今天,由于极度亚微米型的集成电路(IC)问世,安装的组件以数百微微秒(pico,10~(-12)秒)的前沿和后沿时间动作,采用100MHz 以上的时钟速率(Clock rate),使人 相似文献
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我司近期量产某重要客户一款四层板,于成品出货前可靠性测试即288×10sec、三次,出现定位于密集孔分层(详见图一)。且经数次测试,均是密集孔位的非定位性爆板。切片显示爆板均是在P片或芯板中树脂分层(详见图二)。 相似文献
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使用等离子清洗机对六层刚挠结合板进行处理。首先采用单因素分析法确定了工艺中各参数(因素)不同水平对试验指标的影响趋势,并为正交试验的水平选择确定了范围,再运用正交试验得到的优化方法,对清洗后的孔壁进行了热应力等相关试验。结果证明采用优化的工艺参数后,清洗孔壁有较好的孔金属化效果。最佳工艺参数为CF4流量100 cm3/min、O2流量250 cm3/min、处理功率4 000 W、处理时间35 min。等离子清洗后进行二次黑孔化工艺,结果证明黑孔化工艺能够应用于六层刚挠结合板制作。 相似文献
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随着PCB在应用市场领域的不断扩大,对所使用的基板材料性能提出了许多特殊的要求。本篇围绕着汽车电子产品用CCL话题,以松下电工公司此类CCL为研究的主要对象,综述它的可靠性确保、提高方面的技术新进展。 相似文献
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Anisotropic conductive film (ACF) suffers a major drawback in regard to reliability even though it has merits, such as reduction
in interconnection distance, high performance, and environmental friendliness. The factor of thermal warpage may lead to a
highly unreliable electrical connection in the assembly. The work presented in this paper focuses on the online contact-resistance
behavior of the ACF joint during thermal shock and compares the results of two different types of dies (Au/Ni bump and bumpless).
For this work, we used a flip chip of 11 × 3 mm2 in dimension. The flex substrate used was made of polyimide film with an Au/Ni/Cu electrode and daisy-chained circuit for
a matching die-bump pattern. The ACF that was used is an epoxy resin in which nickel and gold-coated polymer balls are dispersed.
Tests for three different thermal-cycling profiles (125°C to −55°C, 140°C to −40°C, and 150°C to −65°C) were carried out.
The samples bonded at a temperature of 180°C, and a pressure of 80 N was used. The initial contact resistances of Au/Ni bump
and bumpless samples were 0.25 ω and 0.4 ω respectively. A comparative study was carried out from the results obtained. The
results showed that for the flip-chip-on-flex (FCOF) packages having an Au/Ni bump, the increase in online contact resistance
is higher than that of the FCOF packages having bumpless chips. For example, in the thermal-cycling profile of 140°C to −40°C,
the online contact resistance for the Au/Ni bump raised to 4.6 ω after 180 cycles, whereas it was only 1.3 ω for the bumpless
sample. The bump height and bump materials were found to be the main factor for such variation. Results show that, above the
glass-transition temperature (Tg), the ACF matrix becomes less viscous, which reduces its adhesive strength and lets the higher bump height of the chip result
in a higher standoff of the package and thus sliding is easier to take place. The responses by the assemblies in hot and cold
conditions are examined, and in-chamber behavior of the assembly is studied and explained. 相似文献
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随着硬件系统的规模不断庞大,其内部精度也逐渐增加,相关的测试工作难度越来越大,在这一过程中应用边界扫描技术则能够较好的解决这一问题。本文主要探讨了边界扫描技术的原理,从设计、优化等各个方便针对边界扫描技术在板级可测性设计中的应用。最终结果提示该技术能够显著降低测试时间,对于提高系统经济价值具有较好的作用。 相似文献
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基于模拟退火的软X射线多层膜反射镜设计 总被引:1,自引:1,他引:0
基于模拟退火(SA)算法,对软x射线短波段中的几个波长的多层膜反射镜进行了优化设计,获得了它们的光学参数,包括多层膜反射镜的最佳周期厚度、最佳厚度比和峰值反射率,进而制作多层膜反射镜并在北京同步辐射装置上进行了反射率的实际测量。测量结果表明,该反射镜具有实用的反射率。这表明,SA方法适用于软x射线短波段多层膜反射镜的优化设计。 相似文献