共查询到20条相似文献,搜索用时 15 毫秒
1.
Ag对Sn-Pb电子钎料合金性能的影响 总被引:2,自引:0,他引:2
研究了Ag的合金化对Sn-Pb钎料合金材料性能的影响。并从钎料的润湿性能,机械性能及抗腐蚀性能等方面讨论了Ag的有利作用,研究表明,在一些特定条件下的电子元件的焊接,Sn-Pb-Ag钎料可部分地或全部地替代昂贵的遗金属钎料合金。 相似文献
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高密度陶瓷封装倒装焊器件的焊点尺寸已降低至100μm以下,焊点电流密度达到10~4 A/cm~2以上,由此引发的电迁移失效成为不可忽视的问题。以陶瓷封装菊花链倒装焊器件为研究对象,开展了Sn10Pb90、Sn63Pb37焊点热电环境可靠性评估试验,通过电连接检测及扫描电子显微镜(SEM)等方法对焊点互连情况进行分析。结果表明,Sn63Pb37焊点阴极侧金属间化合物(IMC)增长明显,表现出明显的极化现象,IMC厚度的平方与通电时间呈线性关系。通电时间达到576 h后Sn63Pb37焊点阴极侧产生微裂纹,而Sn10Pb90焊点在通电576 h后仍未出现异常,表现出优异的电迁移可靠性。研究结果对于直径100μm微焊点的陶瓷封装倒装焊器件的应用具有重要的意义。 相似文献
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The addition of small amounts of Ag (less than ~;0.5 wt. %) is found to significantly improve the ductility of the binary
Bi-Sn eutectic solder. The ductility improvement, more than a threefold increase in tensile elongation, is observed even at
a relatively high strain rate (0.01 s-1). As the Bi-Sn binary eutectic alloy tends to fail catastrophically by brittle fracture at high strain rates, the reduced
strain-rate sensitivity in the Ag-containing alloy is beneficial for improving solder reliability on sudden impacting as might
be encountered during device assembly, shipping, or thermal shock/cycling. The observed increase in alloy ductility by Ag
additions is attributed to a substantial refinement of the solidification microstructure. 相似文献
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Platinum does not oxidize easily, and has slow reaction rates with Sn-based solders. Due to these two positive attributes,
a single platinum layer has the potential to replace both the oxidation protection layer and the diffusion barrier layer in
the underbump metallurgy of flip-chip devices. To evaluate this potential further, the dissolution rate and the wetting properties
of Pt were investigated in this study. It was found that Pt did have a dissolution rate less than half that of Ni, currently
the most popular barrier layer material. The wetting properties of Pt were not as good as those of Ni but were nevertheless
still acceptable for industrial applications. In short, as far as the dissolution and the wetting characteristics are concerned,
Pt is an effective top surface layer for use in underbump metallurgy. 相似文献
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David Witkin 《Journal of Electronic Materials》2012,41(2):190-203
The creep behavior of Sn-3.0Ag-0.5Cu (SAC305), Sn-3.4Ag-1.0Cu-3.3Bi (SAC-Bi), and Sn-3.4Ag-4.8Bi (SnAg-Bi, all wt.%) was studied
in constant-stress creep tests from room temperature to 125°C. The alloys were tested in two microstructural conditions. As-cast
alloys had a composite eutectic-primary Sn structure, while in aged alloys the eutectic regions were replaced by a continuous
Sn matrix with coarsened intermetallic (Cu6Sn5 and Ag3Sn) particles. After aging, Bi in SAC-Bi and SnAg-Bi was found as precipitates at grain boundaries and grain interiors. The
creep resistance of of-cast SAC305 was higher than that of as-cast Bi-containing alloys, but after aging the SAC305 had the
lowest creep resistance. The creep strain rates in SAC-Bi and SnAg-Bi were much less affected by aging. The apparent activation
energy for creep was also changed more for SAC305 than for the other two alloys. The creep behavior of SAC-Bi and SnAg-Bi
can be understood by considering the solubility of Bi in Sn. The difference in creep behavior between as-cast and aged SAC-Bi
is greatly reduced when room-temperature test results are excluded from analysis. This suggests that the strongest influence
on creep in these alloys is due to Bi solute interaction with moving dislocations during deformation. 相似文献
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无铅电子钎料合金蠕变性能研究 总被引:7,自引:0,他引:7
设计制作了一种简单可靠的弯折蠕变测量装置,比较了两种无铅电子钎料合金Sn-9Zn和Sn-3.5Cu-0.7Ag与传统电子钎料合金Sn-40Pb的常温蠕变性能,以及冷却条件对其蠕变强度的影响。结果表明:两种无铅钎料的抗蠕变性能大大优于传统锡铅钎料;Sn-3.5Ag-0.7Cu合金的抗蠕变性能优于Sn-9Zn合金;冷却速率对Sn-9Zn合金和Sn-3.5Ag-0.7Cu合金组织的影响类似,然而对蠕变强度的影响却相反:水冷使两种合金的组织相对于空冷都明显细化,Sn-9Zn合金的蠕变强度因之降低,而Sn-3.5Ag-0.7Cu合金的蠕变强度却因之提高。对可能产生的原因进行了讨论。 相似文献
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Sn-Ag和Sn-Zn及Sn-Bi系无铅焊料 总被引:24,自引:5,他引:19
随着微电子组装技术的发展,研制新型的和实用的无铅焊料替代传统的Sn-Pb焊料已成为近年的研究热点。介绍了目前最常见的Sn-Ag、Sn-Zn和Sn-Bi为基体的无铅焊料并与传统的Sn-Pb焊料的性能进行了比较。 相似文献
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Xu Chen Feng Xue Jian Zhou Sidong Liu Guotong Qian 《Journal of Electronic Materials》2013,42(8):2708-2715
The microstructures, phase transformations, and wettability of Sn-Bi-Zn solder alloys were investigated by scanning electron microscopy, x-ray diffraction, and differential scanning calorimetry (DSC). The results show that the alloys are composed of primary Sn-rich phase or Zn-rich phase, (Sn + Zn) eutectic structure, and (Sn + Bi + Zn) ternary eutectic structure. The microstructural characterization of Sn-xBi-Zn alloys indicates that, with increasing Bi content, more of the eutectic (Sn-Bi-Zn) structures is formed. DSC profiles reveal that the eutectic peak of the samples did not differ very much, but the reaction temperature of the alloys decreases with increased Bi content. The spreading rates of solders increased with the addition of Zn, which affects the interfacial reactions between the solders and copper. 相似文献
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Zhanli Guo Nigel Saunders Peter Miodownik Jean-Philippe Schillé 《Journal of Electronic Materials》2008,37(1):23-31
A full set of physical and thermophysical properties for lead-free solder (LFS) alloys have been calculated, including liquidus/solidus
temperatures, fraction solid, density, coefficient of thermal expansion, thermal conductivity, Young’s modulus, viscosity,
and liquid surface tension, all as a function of composition and temperature (extending into the liquid state). The results
have been extensively validated against data available in the literature. A detailed comparison of the properties of two LFS
alloys Sn-20In-2.8Ag and Sn-5.5Zn-4.5In-3.5Bi with Sn-37Pb has been made to show the utility and need for calculations that
cover a wide range of properties, including the need to consider the effect of nonequilibrium cooling. The modeling of many
of these properties follows well-established procedures previously used in JMatPro software for a range of structural alloys.
This paper describes an additional procedure for the calculation of the liquid surface tension for multicomponent systems,
based on the Butler equation. Future software developments are reviewed, including the addition of mechanical properties,
but the present calculations can already make a useful contribution to the selection of appropriate new LFS alloys. 相似文献
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K. E. Yazzie H. Fei J. J. Williams H. Jiang N. Chawla 《Journal of Electronic Materials》2009,38(12):2746-2755
With the increasing focus on developing environmentally benign electronic packages, Pb-free alloys have received a great deal
of attention. Mishandling of packages during manufacture, assembly or by the user may cause failure of the solder joint. A
fundamental understanding of the behavior of Pb-free solders under mechanical shock conditions is lacking. Reliable experimental
stress–strain data over a range of strain rates needs to be obtained for reliability models. In this paper we report on the
intermediate strain rate behavior of pure Sn solder. The first part of the paper discusses modeling and analysis of the specimen
geometry to obtain a relatively uniform stress (and strain) distribution within the gage section. Analysis by the finite element
method (FEM) showed that a modified specimen geometry, with 10 mm gage length, provided a homogeneous strain distribution,
similar to the American Society for Testing and Materials (ASTM) E8 specimen geometry. The second part describes microstructural
characterization and experimental results on pure Sn at intermediate strain rates (~10/s). Ultimate tensile strength and strain
to failure in the 10 mm specimen were quite similar to those of the ASTM specimen. A double necking phenomenon was observed
in the ASTM specimen, which was not observed in the 10 mm specimen. FEM modeling of the dynamic behavior of the solder correlated
very well with the experimental observations. 相似文献
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Influence of Surface Segregation on Wetting of Sn-Ag-Cu (SAC) Series and Pb-Containing Solder Alloys
M. J. Bozack J. C. Suhling Y. Zhang Z. Cai P. Lall 《Journal of Electronic Materials》2011,40(10):2093-2104
Wetting of Sn-Ag-Cu (SAC) series solder alloys to solid substrates is strongly influenced by surface segregation of low-level
bulk impurities in the alloys. We report in situ and real-time Auger electron spectroscopy measurements of SAC alloy surface compositions as a function of temperature as
the alloys are taken through the melting point. A dramatic increase in the amount of surface C (and frequently O) is observed
with temperature, and in some cases the alloy surface is nearly 80 at.% C at the melting point. The C originates from low-level
impurities incorporated during alloy synthesis and inhibits wetting because C acts as a blocking layer to reaction between
the alloy and substrate. A similar phenomenon has been observed over a wide range of (SAC and non-SAC) alloys synthesized
by a variety of techniques. That solder alloy surfaces at melting have a radically different composition from the bulk uncovers
a key variable that helps to explain the wide variability in contact angles reported in previous studies of wetting and adhesion. 相似文献
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通过对共晶锡铅焊料和PCB UBM层电镀薄金焊盘反应后的界面微观组织观察和焊点断口力学性能分析,系统研究了PCB焊盘薄金对焊点焊接性能的影响。结合Au-Sn合金二元相图理论和Au在Sn中溶解速率,研究结果显示在一定应用场合,利用薄金焊盘可避免搪锡去金工艺,可有效地提高生产效率且无可靠性风险。 相似文献
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随着人们环保意识的提高,无铅焊料替代传统的锡铅焊料成为电子行业的必然趋势。Sn-Zn系无铅焊料因为熔点接近传统锡铅焊料,且具有优良的力学性能而被广泛关注,有望替代传统焊料。目前Sn-Zn系无铅焊料在润湿性、抗氧化性、抗腐蚀性等方面存在一定的问题。其中,焊料的抗腐蚀性对电子产品的寿命和安全起着决定性作用,因此,具有良好的抗腐蚀性能是开发无铅焊料的关键之一。就当下研究比较成熟的Sn-Zn系焊料的抗腐蚀性能进行研究。指出了元素合金化对Sn-Zn焊料的影响,并对抗腐蚀机理进行阐述。 相似文献