共查询到19条相似文献,搜索用时 187 毫秒
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尽管激光钻孔在印制板(PCB)钻孔中应用得越来越广,但是利用微型钻头在机械钻机上进行的机械钻孔仍然是最重要的PCB钻孔方式。顺应PCB微孔的发展趋势,微型钻头直径越来越小,新型钻头结构不断出现,微钻头性能不断提高,微钻头涂层技术逐步成熟,微孔钻削的研究不断深入,推动着PCB技术的发展。本文即对微钻头及微孔钻削的进展进行总结,对微钻头和微孔钻削的趋势进行展望。 相似文献
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受到水溶液内部复杂基质效应的影响,激光诱导击穿光谱(LIBS)技术在水溶液样品的连续在线检测分析应用中受到很大制约。提出了一种微孔喷射辅助LIBS的新技术,用以实现水溶液中金属元素的连续在线分析。该方法通过微米量级的小孔矩阵和压电陶瓷振荡片将流动液体在线转化成密集的小液滴并连续喷出来,辅助LIBS系统进行检测。依据此思路,设计实现了一套由微孔喷射装置和传统LIBS装置组成的微孔喷射辅助LIBS检测系统。利用该系统,以水溶液中的Ca元素为目标元素展开实验,研究该方法的最优化实验参数、等离子体物理特性和检测能力等。结果表明,该方法对Ca元素的在线检测限能够达到0.96 mg/L,且在0~1124 mg/L范围内谱峰强度和浓度之间具有较好的线性关系。 相似文献
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通过微孔衍射产生高质量的球面波是进行夏克-哈特曼波前传感器(SHWS)高精度标定的关键。采用时域有限差分(FDTD)法,进行了193 nm准分子激光照明下有限厚度有限电导率微孔的衍射仿真计算,分析了照明物镜数值孔径(NA)对微孔衍射波前质量的影响,确定了满足SHWS高精度标定所需微孔直径和照明物镜NA的大小。分析计算得出,采用直径为200 nm的微孔及NA为0.6~0.75的照明物镜时,衍射波前均方根(RMS)偏差为3.50×10-3λ,强度均匀性为0.10,微孔透射率约为0.15,满足SHWS进行纳米精度波像差检测对参考球面波质量的要求。 相似文献
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随着电子信息产品功能的不断强大,对挠性电路板高精密化提出了更高的要求,目前50μm线宽/50μm间距、75μm微孔导通已经成为挠性电路板产品的主要发展趋势,而近年来技术日益更新的高转速钻机为挠性板机械钻微孔创造了条件。本文主要研究挠性板机械钻微孔技术,通过正交实验,对辅材搭配、基材材质特性、基材铜箔类型、钻孔参数等进行了系统试验,找出影响机械钻微孔的关键因子,并通过优化钻孔参数,以达到提高微孔钻孔品质、提高钻孔效率、降低微孔制作成本的目的。 相似文献
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镀金层微孔率检测方法的研究 总被引:4,自引:0,他引:4
为防止连接器在空气中污染腐蚀而导致电接触失效,广泛采用表面镀金工艺。但镀金层较薄,不可避免地出现微孔,形成微孔腐蚀。微孔率是评价连接器镀金质量的重要参数之一。采用潮湿SO2气体加速腐蚀,并配以显微镜分析是一种方便、快速的连接器镀金微孔率检测方法。采用这种方法检测同轴连接器镀金层,发现镀金层厚度不足1 mm时,微孔率大于600个/cm2,随镀金层厚度增加至3 mm以上,微孔率急剧减少,低于60 个/cm2。 相似文献
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介绍了低密度(微孔)聚四氟乙烯的性能特点,探讨了微孔聚四氟乙烯绝缘低损耗同轴射频电缆的制造技术,分析了微孔聚四氟乙烯绝缘低损耗同轴射频电缆优点和推广意义。 相似文献
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应用于HDI/BUM技术领域的超薄铜箔 总被引:1,自引:0,他引:1
介绍了一种比较新颖的、技术要求比较高的,能广泛应用于HDI技术领域的超薄铜箔,并且通过其在图形电镀中的应用及激光钻孔后的电镀效果研究,可以充分体会到这种铜箔优异的性能。 相似文献
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New developments in laser-based fabrication that are an extension of laser microvia drilling technology are helping to reduce feature sizes and facilitating the miniaturization of electronic devices.Baseball, it is said, is only a game. True. And the Grand Canyon is only a hole in Arizona. Not all holes, or games, are created equal. 相似文献
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The creep analyses of solder-bumped wafer level chip scale package (WLCSP) on build-up printed circuit board (PCB) with microvias subjected to thermal cyclic loading are presented. The emphasis of this study is placed on the effects of the thickness of the PCB with a microvia build-up layer on the solder joint reliability of the WLCSP assembly. The 62Sn-2Ag-36Pb solder joints are assumed to follow the Garofalo-Arrhenius creep constitutive law. The shear stress and creep shear strain hysteresis loops, shear stress range, creep shear strain range, and creep strain energy density range at different locations in the corner solder joint are presented for a better understanding of the thermal-mechanical behaviors of the solder-bumped WLCSP on build-up PCB with microvias. It is found that, due to the large coefficient of thermal expansion of the build-up resin, the effects of thickness of the PCB with microvia build-up layer become much more significant than that without the microvia build-up layer 相似文献
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Availability of board solder joint reliability information is critical to the wider implementation of chip scale packages (CSPs). The JPL-led CSP consortia of enterprises representing government agencies and private companies have joined together to pool in-kind resources for developing the quality and reliability of CSPs for variety of projects. In the process of building the consortia test vehicles, many challenges were identified regarding various aspects of technology implementation. This paper will present our experience in the areas of technology implementation challenges, including design and building both standard and microvia boards, and assembly of two types of CSP test vehicles. 相似文献