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大管脚数的表面安装塑封器件新的失效机理的研究 总被引:2,自引:0,他引:2
焦慧芳 《电子产品可靠性与环境试验》1998,(5):30-33
本文简述了塑封器件的特点及其发展,和随之而出现的新的失效机理,塑封分层剥离,开裂(俗称“爆米花”效应)。并通过对一个QFP80脚表面安装(SMD)塑封器件微处理单元电路的失效分析,使用先进的手段证实了大管脚表面安装塑封器件管壳的分层剥离产生的应力可使键合接头开裂,导致器件电失效,及塑封分层剥离,开裂产生的原因,提出了避免此类现象发生的合理建议。 相似文献
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塑封集成电路离层对可靠性的影响及解决方法 总被引:2,自引:2,他引:0
塑封集成电路因其是非气密性封装,封装材料热膨胀系数的不同以及被粘接材料表面能低,是造成塑封电路离层或开裂的内部原因。通过选择特殊的封装材料(特别是框架材料)和工艺可以解决离层或开裂问题,大大提高塑封集成电路的稳定性和可靠性。水汽是造成塑封集成电路离层或开裂的外部原因,可以通过驱除和防潮措施来解决。要提升塑封集成电路可靠性,必须从技术和工艺上解决塑封电路离层或开裂问题。我们在这方面做了有益的尝试,取得了良好的效果,为拓展塑封集成电路的应用领域创造了条件。 相似文献
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随着科技的发展,半导体元器件小型化、高性能、轻量化的需求日益迫切,塑封倒装焊技术得到了广泛应用。因为基板的易形变性及各封装材料间的热膨胀系数不匹配,焊点开裂成为影响封装可靠性的重要因素之一。为了研究倒装焊产品在封装制程中焊点开裂的失效原因,利用有限元分析(ANSYS)软件建立倒装焊塑封封装体有限元模型,模拟回流焊过程中的塑封基板形变与凸点应力分布,并分析焊点开裂失效的原因。结果表明,在回流焊过程中,基板形变量大于裸芯,外围凸点倾斜较大,承受的应力及应变能最大,外沿凸点为最易失效点,采用加载具作业可显著降低失效风险。 相似文献
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JQX-72F继电器具有体积小、耐压高、切换能力强、安装方便、塑封型封装型式等特点。介绍该产品的原理、结构、技术性能参数。 相似文献
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在引线框架塑封集成电路的引线冲切成型过程中,存在塑封体破裂脱落、引脚折断等异常现象,如果不能及时发现这些异常,就会造成产品的批量报废或相关成型模具损坏的情况.介绍了如何使用光电传感器和检测针系统对集成电路引脚冲切成型中可能出现的异常进行有效监测和防护. 相似文献
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塑封球栅阵列(BGA)是一种新型表面安装多端子型LSI封装。与塑封四方扁平封装(QFP)相比,前者外形更小,设备与操作较为简单,可靠性也有所提高。BGA替代QFP的尝试从美国开始,并正在各国展开 相似文献
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塑封球栅列(BGA)是一各新型表面安装多端子型LSI封装。与塑封四方扁平封装(QFP)相比,前者外形更小,设备与操作较为简单可靠性民提高。BGA替代QFP的尝试从美国开始,并正在各国展开。 相似文献
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This work benchmarks the current reliability tests used by the electronics industry, examines those tests that affect and are affected by molding compounds, discusses the relevance of accelerated testing, and addresses the major reliability issues facing current molding compound development efforts. Six compound-related reliability concerns were selected: moldability; package stresses; package cracking; halogen-induced intermetallic growth at bond pads; moisture-induced corrosion; and interfacial delamination. Causes of each failure type are surveyed and remedies are recommended 相似文献
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Acoustical microscopy is gaining wide acceptance in the microelectronic packaging community. C-mode scanning acoustical microscopy, C-SAM, is widely used in package evaluations and for failure analysis. This paper discusses several specific topics. These include: (1) popcorn cracking in SMDs; (2) an evaluation of solder die attach in power packages; (3) an instance of top of die delamination which resulted in electrical failures; and (4) moisture sensitivity of other surface mount power packages and how it resulted in ball bond degradation during a new product qualification. 相似文献
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Mohammadreza Keimasi Michael H. Azarian Michael Pecht 《Microelectronics Reliability》2007,47(12):2215-2225
Multilayer ceramic capacitors (MLCCs) are known to experience flex cracking when subjected to bending stresses. An experimental study was conducted to determine the susceptibility to flex cracking of flexible- and standard-termination surface mount MLCCs assembled with lead-free or tin–lead solders and aged at two different temperatures for 200 h. Experimental results showed that MLCCs mounted on printed circuit boards with lead-free solder are less susceptible to flex cracking compared with MLCCs mounted on boards with eutectic tin–lead solder. Two factors which make capacitors assembled with lead-free solder less susceptible to flex cracking were discussed: the lower tensile stresses inside the capacitor body which are a result of the differing elastic–plastic mechanical properties of the solder, and the higher residual compressive stresses after solder reflow assembly which are a result of the higher solidification temperature for the Sn3.0Ag0.5Cu lead-free solder. Flexible-termination MLCCs showed much more resistance to flex cracking in comparison to standard-termination MLCCs assembled with both lead-free and tin–lead solders. Aging at elevated temperatures had little effect on flex cracking susceptibility of MLCCs assembled with tin–lead solder. For MLCCs assembled with lead-free solder, aging at 150 °C increased the susceptibility to flex cracking in comparison with un-aged MLCCs. 相似文献
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自20世纪80年代以来,表面贴装技术已在电子工业中得到了广泛的应用和发展。本文从SMT设备、表面安装电路基板、表面安装元件、辅助材料、生产线管理等五个方面对其未来的发展趋势作了初步分析。 相似文献
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本文综合性地介绍了国内外表面安装技术与表面安装元件的发展现状、技术水平、市场动向,以及今后尚需开发的主要课题。 相似文献
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Stephen Ridout Milos Dusek Chris Bailey Chris Hunt 《Microelectronics Reliability》2006,46(12):2122-2130
This paper presents both modelling and experimental test data to characterise the performance of four non-destructive tests. The focus is on determining the presence and rough magnitude of thermal fatigue cracks within the solder joints for a surface mount resistor on a strip of FR4 PCB. The tests all operate by applying mechanical loads to the PCB and monitoring the strain response at the top of the resistor. The modelling results show that of the four tests investigated, three are sensitive to the presence of a crack in the joint and its magnitude. Hence these tests show promise in being able to detect cracking caused by accelerated testing. The experimental data supports these results although more validation is required. 相似文献
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SMT柔性制造技术研究 总被引:1,自引:0,他引:1
对电子电路表面组装生产的柔性比问题进行了分析研究,提出了利用现有组装设备形成电子电路表面组装柔性制造系统的设计思想,并对其中的系统组成,信息集成,质量保证体系的形成等关键问题进行了探讨。 相似文献
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