共查询到20条相似文献,搜索用时 15 毫秒
1.
An orthogonal method was used to evaluate the effects of Ga, Al, Ag, and Ce multi-additions on the wetting characteristics
of Sn-9Zn lead-free solders by wetting balance method. The results show that the optimal loading of Ga, Al, Ag, and Ce was
0.2 wt.%, 0.002 wt.%, 0.25 wt.%, and 0.15 wt.%, respectively. Intermetallic compounds (IMCs) formed at the interface between
Sn-9Zn-0.2Ga-0.002Al-0.25Ag-0.15Ce solder and Cu substrate were investigated by scanning electron microscope (SEM) and energy
dispersive spectroscopy (EDS) analysis. The SEM images illustrate that the IMCs can be divided into two portions from the
substrate side to the solder side: a planar Cu5Zn8 layer and an additional continuous scallop-like AgZn3 layer. The EDS analysis also shows that Ga segregates in the solder abutting upon the interface. X-ray photoelectron spectroscopy
(XPS) and Auger electron spectroscopy (AES) of the surface components of Sn-9Zn-0.2Ga-0.002Al-0.25Ag-0.15Ce solder indicate
that Al aggregates at the surface in the form of Al2O3 protective film, which prevents the further oxidation of the solder surface. On the other hand, Ce aggregates at the subsurface,
which may reduce the surface tension of the solder and improve the wettability in consequence. 相似文献
2.
The formation and the growth of the intermetallic compounds (IMCs) at the interface between the Sn–8Zn–3Bi–xAg (x = 0, 0.5, and 1 wt.%) lead-free solder alloys and Cu substrate soldered at 250 °C for different durations from 5 to 60 min were investigated. It was found that Cu5Zn8 and CuZn5 formed at Sn–8Zn–3Bi/Cu interface, and Cu5Zn8 and AgZn3 formed at the solder/Cu interface when the solder was added with Ag. The thickness of IMC layers in different solder/Cu systems increased with increasing the soldering time. And the growth of the IMCs was found to be mainly controlled by a diffusion mechanism. Additionally, the growth of the IMC layers decreased with increasing content of Ag in the soldering process. 相似文献
3.
The effect of adding a small amount of rare earth cerium (Ce) element to low Ag containing Sn-1wt%Ag Pb-free solder on its interfacial reactions with Cu substrate was investigated. The growth of intermetallic compounds (IMCs) between three Sn-1Ag-xCe solders with different Ce contents and a Cu substrate was studied and the results were compared to those obtained for the Ce-free Sn-1Ag/Cu systems. In the solid-state reactions of the Sn-1Ag(-xCe)/Cu solder joints, the two IMC layers, Cu6Sn5 and Cu3Sn, grew as aging time increased. Compared to the Sn-1Ag/Cu joint, the growth of the Cu6Sn5 and Cu3Sn layers was depressed for the Ce-containing Sn-1Ag-xCe/Cu joint. The addition of Ce to the Sn-Ag solder reduced the growth of the interfacial Cu-Sn IMCs and prevented the IMCs from spalling from the interface. The evenly-distributed Ce elements in the solder region blocked the diffusion of Sn atoms to the interface and retarded the growth of the interfacial IMC layer. 相似文献
4.
Tomasz Gancarz Janusz Pstrus Katarzyna Berent 《Science & Technology of Welding & Joining》2018,23(7):558-567
This work shows the effect on the soldering process of the addition of Ag and Cu to Sn–Zn alloys. Soldering of Al/Cu and Al/Al joints was performed for a time of 3?min, at a temperature of 250°C, with the use of flux. Aging was carried out at 170°C for Al/Cu and Al/Al joints for 1 and 10 days. During the aging process, intermetallic layers grew at the interface of the Al/Cu joint at the Cu substrate. Intermetallic layers were not observed during wetting of Al/Al joints. On the contrary, dissolution of the Al substrate and migration of Al-rich particles into the bulk of the solder were observed. The experiment was designed to demonstrate the effect of Ag and Cu addition on the dissolution of Al substrate during the soldering and aging processes. In the solder alloys, small precipitates of AgZn3 and Cu5Zn8 were observed. 相似文献
5.
C. C. Jain C. L. Chen H. J. Lai T. H. Chuang 《Journal of Materials Engineering and Performance》2011,20(6):1043-1048
Through the refinement of the (Ce, Zn)Sn3 intermetallic phase, the formation of tin whiskers, previously observed on the surface of a Sn-3Ag-0.5Cu-0.5Ce solder, was
prevented in a Sn-9Zn-0.5Ce alloy. However, whisker growth can still occur on the surface of Sn-8Zn-3Bi-0.5Ce solder after
air storage at room temperature and at 150 °C due to the formation of large (Ce, Zn)Sn3 intermetallic clusters. Further experiments showed that decreasing the Bi-content in this Sn-8Zn-0.5Ce alloy to 1 and 2 wt.%
can recover the beneficial effects of Zn additions on the refinement of the (Ce, Zn)Sn3 phase and obviously reduce the appearance of tin whiskers. In addition, alloying the Sn-8Zn-3Bi-0.5Ce solder with 0.5 wt.%
Ge, which increases the oxidation resistance of the (Ce, Zn)Sn3 intermetallic clusters, can also effectively inhibit tin whisker growth. 相似文献
6.
Understanding the Influence of Copper Nanoparticles on Thermal Characteristics and Microstructural Development of a Tin-Silver Solder 总被引:1,自引:0,他引:1
D.C. Lin T.S. Srivatsan G-X. Wang R. Kovacevic 《Journal of Materials Engineering and Performance》2007,16(5):647-654
This paper presents and discusses issues relevant to solidification of a chosen lead-free solder, the eutectic Sn-3.5%Ag,
and its composite counterparts. Direct temperature recordings for the no-clean solder paste during the simulated reflow process
revealed a significant amount of undercooling to occur prior to the initiation of solidification of the eutectic Sn-3.5%Ag
solder, which is 6.5 °C, and for the composite counterparts, it is dependent on the percentage of copper nanopowder. Temperature
recordings revealed the same temperature level of 221 °C for both melting (from solid to liquid) and final solidification
(after recalescence) of the Sn-3.5%Ag solder. Addition of copper nanoparticles was observed to have no appreciable influence
on melting temperature of the composite solder. However, it does influence solidification of the composite solder. The addition
of 0.5 wt.% copper nanoparticles lowered the solidification temperature to 219.5 °C, while addition of 1.0 wt.% copper nanoparticles
lowered the solidification temperature to 217.5 °C, which is close to the melting point of the ternary eutectic Sn-Ag-Cu solder
alloy, Sn-3.7Ag-0.9Cu. This indicates the copper nanoparticles are completely dissolved in the eutectic Sn-3.5%Ag solder and
precipitate as the Cu6Sn5, which reinforces the eutectic solder. Optical microscopy observations revealed the addition of 1.0 wt.% of copper nanoparticles
to the Sn-3.5%Ag solder results in the formation and presence of the intermetallic compound Cu6Sn5. These particles are polygonal in morphology and dispersed randomly through the solder matrix. Addition of microsized copper
particles cannot completely dissolve in the eutectic solder and projects a sunflower morphology with the solid copper particle
surrounded by the Cu6Sn5 intermetallic compound coupled with residual porosity present in the solder sample. Microhardness measurements revealed the
addition of copper nanopowder to the eutectic Sn-3.5%Ag solder resulted in higher hardness. 相似文献
7.
The effects of Ca, Al, and Ag on the anti-oxidation of Sn-9Zn-X solders and the interface reactions between the solders and Cu substrate were investigated by Auger electron spectroscopy (AES) and scanning electron microscope (SEM) analysis, respectively. The mechanism of improving the wettability of Sn-g Zn lead-flee solder by adding Ca, Al, and Ag was also revealed. The AES analysis indicated that Al and Ca might enrich on the molten solder surface which resulted in improving the anti-oxidation of Sn-gZn-O. O05Al and Sn-gZn-O. 3C, a alloys. The addition of Ca reduced the apparent activation energy and promoted the interface reaction. With the addition of 0.3 wt. % Ag, some scallop-like intermetallic compounds (IMCs) formed at the interface, according to the energy dispersive spectroscopy (EDS) analysis, these scallop-like IMCs might be the mixture of Ag-Zn and Cu-Sn compounds. 相似文献
8.
H.R. Kotadia O. MokhtariM.P. Clode M.A. GreenS.H. Mannan 《Journal of Alloys and Compounds》2012,511(1):176-188
The effect of adding 0.5-1.5 wt.% Zn to Sn-3.8Ag-0.7Cu (SAC) solder alloy during reflow and solid state ageing has been investigated. In particular, the role of the Zn addition in suppressing interfacial Intermetallic Compound (IMC) growth on Cu and Ni-P substrates has been determined. Solder-substrate couples were aged at 150 °C and 185 °C for 1000 h. In the case of 0.5-1.0 wt.% Zn on Cu substrate, Cu3Sn IMC was significantly suppressed and the morphology of Cu6Sn5 grains was changed, leading to suppressed Cu6Sn5 growth. In the SAC-1.5Zn/Cu substrate system a Cu5Zn8 IMC layer nucleated at the interface followed by massive spalling of the layer into the solder, forming a barrier layer limiting Cu6Sn5 growth. On Ni-P substrates the (Cu,Ni)6Sn5 IMC growth rate was suppressed, the lowest growth rate being found in the SAC-1.5Zn/Ni-P system. In all cases the added Zn segregated to the interfacial IMCs so that Cu6Sn5 became (Cu,Zn)6Sn5 and (Cu,Ni)6Sn5 became (Ni,Cu,Zn)6Sn5. The effect of Zn concentration on undercooling, wetting angles and IMC composition changes during ageing are also tabulated, and a method of incorporating Zn into the solder during reflow without compromising solder paste reflow described. 相似文献
9.
Asit Kumar Gain Tama Fouzder Y.C. Chan Ahmed Sharif Winco K.C. Yung 《Journal of Alloys and Compounds》2010,489(2):678-684
The formation of intermetallic compounds and the shear strength of Sn–Zn–Bi solder alloys with various (0, 1, 3, 5 and 7 wt%) weight percentages of Sn–Ag–Cu were investigated on Au/Ni metallized Cu pads depending on the number of reflow cycles. In Sn–Zn–Bi solder joints, scallop-shaped AuZn3 intermetallic compound (IMC) particles were found at the interfaces and in the solder ball regions, fine Bi- and needle-shaped Zn-rich phase were observed in the Sn matrix. After Sn–Ag–Cu additions, an additional Ag–Zn intermetallic compound layer was adhered to the top surface of the AuZn3 layer at the interface and fine spherical-shaped AgZn3 intermetallic compound particles were detected in the solder ball regions together with Bi- and Zn-rich phase volumes. After the addition of Sn–Ag–Cu, the shear strength of Sn–Zn–Bi solder joints increased due to the formation of the fine AgZn3 intermetallic compound particles. The shear strengths of Sn–Zn–Bi and Sn–Zn–Bi/7 wt% Sn–Ag–Cu solder joints after one reflow cycle were about 44.5 and 53.1 MPa, respectively and their shear strengths after eight reflow cycles were about 43.4 and 51.6 MPa, respectively. 相似文献
10.
C.C. Jain S.S. Wang K.W. Huang T.H. Chuang 《Journal of Materials Engineering and Performance》2009,18(2):211-215
The interfacial reactions in a Sn-20In-2.8Ag solder ball grid array (BGA) package with immersion Ag surface finish are investigated.
After reflow, the Ag thin film dissolves quickly into the solder matrix, and scallop-shaped intermetallic layers, with compositions
of (Cu0.98Ag0.02)6(In0.59Sn0.41)5, appear at the interfaces between Sn-20In-2.8Ag solder ball and Cu pad. No evident growth of the (Cu0.98Ag0.02)6(Sn0.59In0.41)5 intermetallic compounds was observed after prolonged aging at 100 °C. However, the growth accelerated at 150 °C, with more
intermetallic scallops floating into the solder matrix. The intermetallic thickness versus the square root of reaction time
(t
1/2) shows a linear relation, indicating that the growth of intermetallic compounds is diffusion-controlled. Ball shear tests
show that the strength of Sn-20In-2.8Ag solder joints after reflow is 4.4 N, which increases to 5.18 N and 5.14 N after aging
at 100 and 150 °C, respectively. 相似文献
11.
Sn-9Zn钎料与内加Cu质点和Cu基体界面生长行为 总被引:1,自引:0,他引:1
在Sn-9Zn无铅钎料中加入Cu金属质点,研究在长时间钎焊条件下钎料/Cu质点、钎料/Cu基体界面金属间化合物(IMCs)的生长行为。结果表明:在钎料/Cu质点和钎料/Cu基体界面处都生成Cu-Zn相(IMCs),其组成为Cu5Zn8+CuZn或Cu5Zn8,而且钎料/质点界面处IMCs的生长速度明显快于钎料/基体处;同时发现,Cu质点的加入大大减小了钎料/Cu基体界面IMCs的厚度。由于Cu质点原位生成Cu-Zn IMCs,消耗了焊点中的Zn,因此Sn-9Zn/Cu接头的可靠性得以提高。 相似文献
12.
《Journal of Alloys and Compounds》2006,407(1-2):141-149
Sn–9Zn (in wt.%) solder ball was bonded to Cu pad, and the effect of aging on shear reliability was investigated. After reflow, the intermetallic compound (IMC) phase formed at the interface was Cu5Zn8, and the as-reflowed Sn–9Zn/Cu joint had sufficient shear strength. In the isothermal aging test, only Cu5Zn8 IMC was observed in the samples aged at temperatures between 70 and 120 °C. On the other hand, after aging at 150 °C for 250 h, Cu6Sn5 phase was observed at the interface between the interfacial Cu5Zn8 IMC layer and the Cu substrate. And, the layer-type Cu5Zn8 IMC layer was disrupted locally at the interface. In the ball shear test conducted after aging treatment, the shear strength significantly decreased after aging at all temperatures for initial 100 h, and then remained constant by further prolonged aging. The fracture mainly occurred at the interface between the solder and Cu5Zn8 IMC layer. The aged Sn–9Zn/Cu solder joint had an inferior joint reliability. 相似文献
13.
The effect on the growth kinetics of the intermetallic compounds (IMCs) in solder/Cu joints, caused by adding Bi to eutectic
Sn-3.5Ag solder alloy, was examined at the aging temperatures of 150°C and 180°C. The Cu6Sn5 layer growth was significantly enhanced, but the Cu3Sn layer growth was slightly retarded by the addition of Bi, resulting in significant growth enhancement of the total (Cu6Sn5+Cu3Sn) IMC layer with increasing Bi addition. The IMC layer growth in the Bi-containing solder joints was accompanied by the
accumulation of Bi ahead of the Cu6Sn5 layer that resulted in the formation of a liquid layer at the Cu6Sn5/solder interface. A kinetic model was developed for the planar growth of the Cu6Sn5 and Cu3Sn layers in the solder joints, accounting for the existence of interfacial reaction barriers. Predictions from the kinetic
model showed that the experimental results could be well explained by the hypothesis that the formation of a Bi-rich liquid
layer at the Cu6Sn5/solder interface reduces the interfacial reaction barrier at the interface. 相似文献
14.
为了寻求一种应用于三维集成电路低温焊接的无铅焊料,基于多组元混合的概念设计并表征(Sn1-xZnx)57-(In0.78Bi0.22)43 (x=0.10,0.15,0.20,摩尔分数,%)四元合金。采用扫描电子显微镜、X射线衍射仪和差示扫描量热仪研究合金的显微组织、热性能和润湿性。结果表明,合金由金属间化合物BiIn2、In0.2Sn0.8和富Zn固溶体组成。随着Zn添加量的增加,BiIn2和富Zn相的体积分数增加。合金的熔点低至70℃,源自低熔点金属间化合物In0.2Sn0.8和BiIn2的形成;合金具有良好的润湿性,润湿角约为40°。在合金和Cu板的界面结合处形成一种薄而坚韧的Cu5Zn8层,提高焊点可靠性。研究表明,通过多组元混合概念设计合金可以有效提高... 相似文献
15.
为进一步促进电子封装用低银无铅钎料的发展,本文采用纳米压痕法研究了新型含Pr低银Sn-0.3Ag-0.7Cu-0.5Ga (SAC-Ga)钎料显微组织与蠕变性能之间的关系。结果表明,SAC-Ga、SAC-Ga-0.06Pr、SAC-Ga-0.5Pr三种钎料的蠕变位移分别为1717 nm、1144 nm、1472 nm;稀土Pr可通过细化Cu6Sn5金属间化合物并促使其均匀分布从而明显提高SAC-Ga钎料的蠕变强度;与SAC-Ga-0.06Pr钎料相比,SAC-Ga-0.5Pr由于过量稀土Pr的表面氧化而导致其蠕变强度有所下降。此外,本文采用Dorn模型研究了含Pr的SAC-Ga钎料的室温蠕变行为并计算了对应的钎料蠕变应力指数n;阐明了Pr对SAC-Ga钎料蠕变强度的强化机理,即当位错遇到细小且均匀分布的Cu6Sn5 金属间化合物时,位错移动只能采用绕过机制,从而提高了含Pr低银钎料的抗蠕变性能。 相似文献
16.
17.
The present study details the microstructure evolution of the interfacial intermetallic compounds (IMCs) layer formed between
the Sn-xAg-0.5Cu (x = 1, 3, and 4 wt.%) solder balls and electroless Ni-P layer, and their bond strength variation during aging. The interfacial
IMCs layer in the as-reflowed specimens was only (Cu,Ni)6Sn5 for Sn-xAg-0.5Cu solders. The (Ni,Cu)3Sn4 IMCs layer formed when Sn-4Ag-0.5Cu and Sn-3Ag-0.5Cu solders were used as aging time increased. However, only (Cu,Ni)6Sn5 IMCs formed in Sn-1Ag-0.5Cu solders, when the aging time was extended beyond 1500 h. Two factors are expected to influence
bond strength and fracture modes. One of the factors is that the interfacial (Ni,Cu)3Sn4 IMCs formed at the interface and the fact that fracture occurs along the interface. The other factor is Ag3Sn IMCs coarsening in the solder matrix, and fracture reveals the ductility of the solder balls. The above analysis indicates
that during aging, the formation of interfacial (Ni,Cu)3Sn4 IMCs layers strongly influences the pull strength and the fracture behavior of a solder joint. This fact demonstrates that
interfacial layers are key to understanding the changes in bonding strength. Additionally, comparison of the bond strength
with various Sn-Ag-Cu lead-free solders for various Ag contents show that the Sn-1Ag-0.5Cu solder joint is not sensitive to
extended aging time. 相似文献
18.
采用润湿平衡法测试了Sn-9Zn-X(X为Ag,Al,Ga)无铅钎料分别配合ZnCl2-NH4Cl钎剂和免清洗助焊剂,在空气和氮气保护的两种条件下的润湿性能,分析研究了合金元素Ag,Al,Ga的添加量对Sn-9Zn-X无铅钎料润湿性的影响规律.结果表明,合金元素Ag,Al,Ga在Sn-9Zn中的最佳添加量(质量分数)分别为0.3%,0.005%~0.02%,0.5%.采用氮气保护可以显著改善Sn-9Zn-X无铅钎料的润湿性,而Sn-9Zn-X无铅钎料配合ZnCl2-NH4Cl钎剂时具有较好的润湿性,甚至优于Sn-3.5Ag-0.5Cu在相同条件下的润湿性.这一研究结果表明,通过研发适合于Sn-Zn系无铅钎料的高性能助焊剂,从而改善Sn-Zn系钎料的润湿性能是完全可行的. 相似文献
19.
The growth kinetics of intermetallic compound layers formed between Sn-3.5Ag solder and Cu substrate were investigated as
a consequence of solid-state isothermal aging. Isothermal aging was carried out in a temperature range between 70°C and 200°C
for 0 to 60 days. A quantitative analysis of the intermetallic compound layer thickness as a function of time and temperature
was performed. The diffusion couples showed a composite intermetallic layer comprised of Cu6Sn5 and Cu3Sn. The growth of intermetallic compounds followed diffusion-controlled kinetics and the layer thickness reached only 9 μm
after 60 day of aging at 150°C. The apparent activation energies were calculated for the growth of the total intermetallic
compound (Cu6Sn5+Cu3Sn); Cu6Sn5 and Cu3Sn intermetallic are 65.4, 55.4 and 75.7 kJ/mol, respectively. 相似文献
20.
SHEN Jun LIU Yongchang Han Yajing GAO Houxiu 《稀有金属(英文版)》2006,25(4):365-370
A lead-free Sn-3.5Ag solder was prepared by rapid solidification technology. The high solidification rate, obtained by rapid cooling, promotes nucleation, and suppresses the growth of Ag3Sn intermetallic compounds (IMCs) in Ag-rich zone, yielding fine Ag3Sn nanoparticulates with spherical morphology in the matrix of the solder. The large amount of tough homogeneously-dispersed IMCs helps to improve the surface area per unit volume and obstructs the dislocation lines passing through the solder, which fits with the dispersion-strengthening theory. Hence, the rapidly-solidified Sn-3.5Ag solder exhibits a higher rnicrohardness when compared with a slowly-solidified Sn-3.5Ag solder. 相似文献