激光微孔加工技术在刚挠性基材中的研究

刚挠结合印制板向高密度互联方向发展,要求线路更细,导通孔直径更小。适合刚挠结合印制板的微导通孔加工工艺在刚挠结合印制板制造工艺中起着关键作用,微孔加工工艺中普遍采用激光技术。文章分析了激光微孔加工中的各影响因素,用正交试验法作对比试验,优化各因素参数,讨论了各因素与基板材料的关系,并拟合出方程定量描述此种关系。根据优化方程选取激光微孔参数,在挠性与刚性基板材料上取得理想效果。     

提高刚挠结合印制板耐热性能制造方法

文章结合航天电子设备焊接和使用环境对印制板的要求,提出刚挠结合印制板在制造过程中仅对挠性连接部位粘贴覆盖膜的方法,提高刚挠结合印制板刚性部位Tg值和耐热性能,为刚挠结合印制板焊接和使用提供可靠保证。     

HDI刚挠印制板中的埋盲孔工艺研究

电子产品日益向便携式发展,使得刚挠结合板的应用也扩大,如今已成为印制板工业中的研究热点。随着组装技术的提高,刚挠结合板出现了改善性设计,高密度互连成为其发展方向之一。文章结合实例,讨论了高密度互连刚挠结合板的制造工艺,并对刚挠结合板中埋盲孔工艺的关键技术做了研究。较详细地研究了埋盲孔工艺中的材料选择、层压、钻孔和孔金属化等问题,得到了较好的工艺参数,并通过飞针测试检测导电性能,孔的合格率达99．9％以上。     

高可靠性18层刚挠结合印制板制作技术研究

文章通过介绍一款用于航空方面的18层高可靠性刚挠结合印制板在压合、盲槽制作、半固化片开窗、覆盖膜压合等技术点的突破,提出一套适用于此类高层高阶刚挠结合印制板的制作技术。     

刚挠多层印制鞭分层原因探讨

本文通过对板面处理、粘结片、层压温度等试验及理论研究，分析了刚挠多层印制板出现分层的原因和解决方法。     

挠性板部分埋入制作刚挠结合板

介绍了一种刚挠结合板制作新技术,只在需要弯折的部位埋入挠性板,通过挠性板使各刚性板之间实现互连。详细分析了设计与材料对刚挠结合板的影响,研究了预压合保护膜、挠性板埋入层压等关键工艺,给出了工艺难点的具体解决办法。结果表明,该技术提高了挠性板材的使用率,简化了挠性板及刚挠结合板加工工艺,使刚挠结合板成品率提高至少8%。     

刚挠结合印制板的加工工艺研究

随着电子技术的发展,尤其是电子组装技术的不断进步,很多场合下一般的刚性印制板已经很难满足电子产品“轻、薄、短、小”的要求。因此,刚挠结合印制板(挠性基材和刚性基材结合的印制板)的应用由于其显著的优越性有着越来越广泛的前景。本文主要介绍刚挠结合印制板的加工工艺,指出了加工过程的技术难点,并提出了解决办法。     

刚挠印制板镀覆孔孔壁开裂原因分析

为适应电子产品的发展,刚挠印制板的应用范围越来越大,用户对刚挠板性能的要求越来越高.概述了刚挠印制板镀覆孔孔壁发生开裂的原因,从基材、钻孔、孔金属化前处理和化学镀铜等角度分析并解决镀覆孔开裂问题.     

刚挠结合印制板类型与制造技术

文章从刚挠印制板的挠曲性和结构不同,叙述了各种刚挠印制板的类型及其制作过程。     

文献与摘要（99）

类似于挠性印制板安装的刚挠板制造 文章描述了一种类似于Occam工艺制造刚挠印制板,并在刚性部分预先安装了元器件。其工艺过程为采用载板贴装元器件,并用树脂密封,然后除去载板,元件端形成导通孔和再形成电路图形,最后层压覆盖膜及挠曲部分铣切除去刚性树脂,得到R-FPCB。     

Fabrication and Reliability of Rigid-Flexible Optical Electrical Printed Circuit Board for Mobile Devices

A rigid-flexible optical and electrical printed circuit board (RFOE-PCB) was fabricated using a conventional PCB manufacturing process for mobile devices. The RFOE-PCB was designed to be embedded with a flexible 45-ended optical waveguide. In order to apply it to mobile devices, a repeating folding test and an environment test were carried out for physical and optical reliability. The RFOE-PCB successfully passed the reliability tests.     

移动设备用光电刚挠印制电路板的制作及其可靠性研究

文章采用传统PCB工艺制作了一种可以应用于移动设备的光电刚挠印制板（RFOE—PCB）。该板被嵌入了端角为45°的挠性光波导线。为了检验其在移动设备中的适用性,使用重复弯曲试验和环境试验来检测它的物理和光学可靠性,结果非常理想。     

有铅和无铅BGA混装工艺研究

分析比对了有铅和无铅两种焊料的不同温度特性。针对军工产品经常面对的有铅和无铅BGA同时组装在一块印制板上的情况,提出了有铅和无铅BGA混合组装的工艺难点。通过工艺试验列举了混合组装中各个环节所应注意的要点,强调要加强过程控制。最后利用各种可靠性试验和分析证明了混合组装焊点的可靠性。     

空间电子设备电路板可靠性可测试性设计检查

为了提高空间电子设备可靠性和可测试性设计的工作质量,采取在印制电路板生产前对其进行可靠性和可测试性设计检查的方法,可以提前在产品研发设计阶段发现可靠性和可测试性设计的不足,有针对性的加以改进,就能进一步提高产品质量与可靠性。列举了印制电路板可靠性可测试性设计检查要点,具有实际工程应用价值。     

离心清洗设备的研制

离心清洗是针对印制电路板焊接后的一种有效清洗方法,离心作用不仅能对印制电路板表面污染物产生很好的渗透、溶解和去污效果,而且不损伤元器件。重点介绍了离心清洗设备的主要结构、关键技术、创新点以及实际应用情况。通过试验和测试证明,离心清洗设备可以很好地满足高精度和高可靠性PCBA的清洗要求。     

Design of Experiments for Board-Level Solder Joint Reliability of PBGA Package Under Various Manufacturing and Multiple Environmental Loading Conditions

A design of experiments was conducted to determine the reliability of plastic ball grid array packages under various manufacturing and multiple environmental loading conditions. Parameters included conformal coating methods, underfill, solder mask defined, and non-solder mask defined pads. Board-level temperature cycling, vibration, and combined temperature cycling and vibration testing were performed to quantify the reliability and identify preferred design parameters. Through the main effects and interaction analysis, test results show underfill is the key parameter related to the solder joint reliability improvement. Conformal coat method and printed circuit board pad design are not main effects on solder joint reliability. No interactive relationship exists among these three factors under temperature cycling loading, but some interactive relationship between printed circuit board pad type and the conformal coating method exists under vibration and combined loading conditions.     

Handheld use condition-based bend test development

For handheld electronic applications such as cell phones and personal digital assistants (PDAs), repeated key strokes could result in considerable flexure of the printed circuit board (PCB) mounted inside the housing. In this study, a standardized four-point bend test, including test board design, test setup, and test input level, has been developed. The S-N curve has been obtained by plotting the reliability at all deflection levels as a function of solder joint strain energy density. The effect of test frequency has also been evaluated. The reliability model prediction of three-point bend reliability matches the experimental data extremely well. The transfer function between reliability stressing and field condition is a strain-energy-density-based power law relationship. Finite-element simulation has been conducted for the worst case cell phone subjected to key presses. The use condition data including strain profiles and frequency have been incorporated in the field life prediction. The four-point bend performance can be converted into the component reliability during cell phone field use conditions. This study establishes the correlation between the use conditions and reliability tests. The cyclic four-point bend test will be implemented in the Joint Electron Device Engineering Council (JEDEC) bend test standard for handheld components.     

Mechanical deflection system (MDS) test and methodology for PBGAsolder joint reliability

A mechanical deflection system (MDS) was developed for highly accelerated tests to evaluate the solder joint fatigue performance in printed circuit board assemblies. The MDS test system can be used for design verification and qualification tests for solder joint reliability. Cyclic twisting deformation is imposed on an assembled printed circuit board (PCB) at isothermal conditions. The MDS test technique makes a significant contribution to reducing solder joint reliability testing cycle time. Fatigue performance of the PBGA solder joints subjected to the MDS test was investigated by three-dimensional finite element modeling. The solder joint fatigue lives were computed for several different MDS test conditions     

红外成像技术在自动测试设备中的应用

“印制电路板故障红外诊断仪”是集光、机、电和计算机一体化的非接触式故障诊断系统。文中详细介绍了该系统的组成、功能及特点,描述了在系统研制过程中解决的主要关键技术问题和难点。该系统硬件由热像仪、计算机、图像采集处理卡、信号源、交直流电源、测试平台等部分组成,软件由故障诊断、信息处理、开发服务等模块组成。该系统具有自动、手动两种诊断方式,其故障诊断速度快、准确率高,通用性强、适用面广。