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开发高性能的无铅波峰焊料合金 总被引:1,自引:0,他引:1
确信电子组装材料部 《电子工业专用设备》2004,33(8):50-57
无铅波峰焊已经发展为两个主要的合金体系:SnAgCu锡/银/铜体系通常含银量达3至4%和基于SnCu锡铜共晶体系。如果按照用户的价值方程式来衡量,二者都存在固有的缺陷。含银3%至4%的SnAgCu体系可提供良好的可靠性和工艺良率,但原材料的成本昂贵。作为替代品的SnCu共晶体系及其改性合金SnCuNi的原材料成本较低,但其工艺良率和焊接可靠性存在问题。为了克服现有焊料体系的缺点,确信电子开发出新型焊料合金SACX0307。研究SAC305、Sn99.3Cu0.7、改性Sn99.3Cu0.7SnCuNi和SACX0307四种合金系的测试结果,评估无铅焊接工艺的4个主要特性:工艺良率、铜浸出率、浮渣形成和热机械可靠性。波峰焊实验使用了测试电路板专门设计较复杂,以区分不同加工条件下的差异、三种助焊剂包括水基和醇基配方和两种电路板表面处理铜OSP和浸银处理。测试表明,SACX0307填补了SAC305合金与SnCu共晶合金系列之间的空白,就波峰焊的四个主要特性而言,其性能优于Sn99.3Cu0.7和SnCuNiSn99.3Cu0.7,而原材料成本低于SAC305。 相似文献
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《现代表面贴装资讯》2011,(6):27-27
全球市场的先进焊料供应商日本斯倍利亚(Nihon Superior)有限公司突出展示其独特SN100C无铅焊料在回流焊接工艺中抑制铜腐蚀的更出色效果。针对目前市场上供应的各种低银和无银不含铅焊料的索赔和反索赔日益增多, 相似文献
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白蓉生 《现代表面贴装资讯》2004,3(3):1-11
无铅焊料之波焊比起熔焊米还要麻烦,若仍以SnAgCu之锡料而言。其机组中的锡池平均温度,须增高50℃而约在250℃至260℃左右;至于焊接瞬间的波峰温度则更将高达280℃以上(约3-6秒),且预热时间亦需加长,以减少高温的冲击。如此之热量大增 相似文献
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Sn—Ag—Cu无铅焊料性能研究 总被引:2,自引:0,他引:2
环保和微电子器件高度集成化的发展驱动了高性能无铅焊料的研究和开发,Sn—Ag-Cu系无铅焊料由于具有良好的焊接性能和使用性能,已逐渐成为一种通用电子无铅焊料。文章通过实验的方法,研究了8种不同配比的Sn—Ag—Cu焊料中银、铜含量对合金性能(包括熔点、润湿性和剪切强度)的影响,并对焊料的显微组织进行对比与分析,得出低银焊料的可靠性比高银焊料好,同时Sn-2.9Ag—1.2Cu的合金具有较低的熔点且铺展性好,为确定综合性能最佳的该系焊料合金提供了依据。 相似文献
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介绍了2,9-二甲基-1,10-二氮杂菲分光光度法测定锡铅焊料中微量铜的含量的方法,该实验方法简便、快捷、准确,适用于铜含量在0.001%-0.1%范围内的锡铅焊料测定。 相似文献
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《电子工业专用设备》2011,40(12):60-60
<正>全球市场的先进焊料供应商日本斯倍利亚(Nihon Superior)有限公司突出展示其独特SN100C?无铅焊料在回流焊接工艺中抑制铜腐蚀的更出色效果。针对目前市场上供应的各种低银 相似文献
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The impact of isothermal aging and recrystallized grain structure distribution on mechanical shock and thermal cycling performance of solder joints with 1% and 3% silver content Sn-Ag-Cu interconnects were investigated. Localized recrystallized grain structure distributions were analyzed to identify correlations between the microstructure evolution and shock performance. The results reveal that the shock tolerance depends on the amount of shock energy that can be absorbed during each shock cycle, which depends on microstructural features. Based on the recrystallized grain distribution, additional isothermal aging in 1% silver Sn-Ag-Cu interconnects shows improved shock performance, whereas degraded shock performance was observed in 3% Sn-Ag-Cu interconnects. Using the same grain boundary distribution analysis on thermally cycled samples, relationships between the particle size distribution, localized recrystallized grain structure development, shock, and thermomechanical performance were identified: finer particle spacing is beneficial for thermal cycling as it resists grain boundary generation, while conversely, wider particle spacing facilitates recrystallization and grain boundary mobility that allows Sn to absorb shock energy. 相似文献
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Polina Snugovsky Zohreh Bagheri Craig Hamilton 《Journal of Electronic Materials》2009,38(12):2628-2646
This paper describes the results of an intensive microstructural and reliability study of pin-through-hole (PTH) and surface
mount technology (SMT) components which were wave solder assembled using three groups of alloys: (1) near-eutectic Sn-Ag-Cu
alloys such as SAC405 and SAC305, (2) low-Ag off-eutectic Pb-free alloys with an Ag content of about 1% and lower, and (3)
eutectic Sn-Cu alloys with Ni and other additives. Both primary attach and reworked solder connections using solder fountain
and hand rework were studied. The PTH connector types and SMT components were wave solder assembled on a test vehicle. Accelerated
thermal cycling (ATC) was conducted at 0°C to 100°C for 6000 cycles. The difference in microstructures, intermetallic formation,
Cu dissolution, grain coarsening, and crack formation is shown. The influence of the microstructure after assembly and rework
on Weibull plot parameters and failure modes is described for 2512 resistors. Interconnect defects such as nonuniform phase
distribution and void formation are discussed. The Sn-Cu-Ni- and Sn-Cu-Ag-Bi-based alloys tested in this study are recommended
as potential suitable replacements for SAC305/405 in the wave solder process; no failure was detected up to 6000 cycles at
0°C to 100°C. Although SAC405 demonstrated better barrel fill and lower rate of crack propagation during ATC, after PTH rework,
both of the alternative Pb-free alloys have a much lower Cu dissolution rate and definitely outperform SAC405 in ATC. SAC405
glue and wave resistors after primary attachment and rework demonstrate higher reliability than alternative alloys. Early
failures relate to alternative alloy characteristics and should be considered for some applications. 相似文献
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Understanding the sensitivity of Pb-free solder joint reliability to various environmental conditions, such as corrosive gases, low temperatures, and high-humidity environments, is a critical topic in the deployment of Pb-free products in various markets and applications. The work reported herein concerns the impact of a marine environment on Sn-Pb and Sn-Ag-Cu interconnects. Both Sn-Pb and Sn-Ag-Cu solder alloy wafer-level packages, with and without pretreatment by 5% NaCl salt spray, were thermally cycled to failure. The salt spray test did not reduce the characteristic lifetime of the Sn-Pb solder joints, but it did reduce the lifetime of the Sn-Ag-Cu solder joints by over 43%. Although both materials showed strong resistance to corrosion, the localized nature of the corroded area at critical locations in the solder joint caused significant degradation in the Sn-Ag-Cu solder joints. The mechanisms leading to these results as well as the extent, microstructural evolution, and dependency of the solder alloy degradation are discussed. 相似文献
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Wenxing Dong Yaowu Shi Yongping Lei Zhidong Xia Fu Guo 《Journal of Electronic Materials》2009,38(9):1906-1912
In the present work, solidification cracks in Sn-Ag-Cu solder joints were investigated. Experimental results indicate that
solidification cracks existed in significant numbers in the miniature Sn-Ag-Cu solder joints. In order to create solidification
cracks in the miniature solder joints during solidification and evaluate the susceptibility of Sn-Ag-Cu alloys to solidification
cracking, a copper self-restraint specimen was designed, which can simulate the process of solidification crack formation.
The solidification crack susceptibility of the Sn-Ag-Cu solder alloy was evaluated using the total crack length of the solder
joint. In addition, the effect of trace amounts of elemental additions on solidification cracking of Sn-Ag-Cu solder joints
was studied. It was found that adding trace amounts of Ni or Ce could depress the solidification cracks in Sn-3.0Ag-0.5Cu
solder joints. However, P additions aggravated the formation of solidification cracks. 相似文献