RE对SnAgCu钎料合金及焊点性能的影响

利用JSM-5610LV扫描电镜（SEM）及能谱分析（EDS）等测量方法,研究了微量RE对Sn-2.5Ag-0.7Cu无铅钎料的显微组织、润湿特性、拉伸强度及焊点剪切强度和蠕变断裂寿命的影响。结果表明,向Sn-2.5Ag-0.7Cu中添加0.1%RE可明显细化钎料合金的显微组织,改善钎料合金的润湿特性,提高钎料合金的抗拉强度、伸长率及焊点剪切强度,增加焊点的蠕变断裂寿命。当RE添加量为0.5%时,由于形成了RE化合物而明显恶化钎料合金的性能。     

热冲击下Sn2.5Ag0.7Cu0.1RE0.05Ni/Cu钎焊接头组织与性能

借助于SEM、EDS、XRD等检测手段对Sn2.5Ag0.7Cu0.1RE0.05Ni/Cu钎焊接头进行观察分析,研究了钎焊工艺参数及热冲击条件对Sn2.5Ag0.7Cu0.1RE0.05Ni/Cu钎焊接头界面金属间化合物和力学性能的影响。结果表明:添加0.05%(质量分数)Ni能细化Sn2.5Ag0.7Cu0.1RE钎料合金的初生β-Sn相和共晶组织;钎焊温度270℃和钎焊时间240 s时,钎焊接头抗剪切强度最大达26.9 MPa,较未添加Ni的钎焊接头提高8.9%;随着热冲击周期的增加,钎焊接头界面金属间化合物层平均厚度增加,界面粗糙度先增大后减小,钎焊接头强度降低;添加0.05%Ni能够抑制接头界面金属间化合物的成长、钎焊接头强度的降低,有利于改善接头可靠性。     

RE对Sn2.5Ag0.7Cu/Cu焊点性能的影响

利用X射线衍射分析仪(XRD)和JSM-5610LV扫描电镜(SEM)研究RE含量对Sn2.5Ag0.7Cu/Cu焊点界面区显微组织、剪切强度和蠕变断裂寿命的影响。结果表明:Sn2.5Ag0.7CuxRE焊点界面区金属间化合物由靠近钎料侧Cu6Sn5和靠近Cu基板侧Cu3Sn构成;添加微量RE可细化Sn2.5Ag0.7Cu焊点内钎料合金的显微组织和改善钎焊接头界面区金属间化合物的几何尺寸及形态;当RE添加量为0.1%时,焊点的剪切强度最高,蠕变断裂寿命最长。     

Sn-9Zn-xCe钎料显微组织及钎焊性能的分析

研究了添加稀土元素Ce对Sn-9Zn无铅钎料的润湿铺展性能、显微组织和焊点力学性能的影响.结果表明,Ce元素的加入改善了钎料的润湿铺展性能,质量分数为0.08%时,钎料的铺展面积达到最大,润湿性能最佳.随着Ce元素的加入,钎料的基体组织得到细化,富Zn相逐渐减少,当元素Ce的添加量大于0.08%时,钎料的显微组织中出现块状稀土元素Ce和Sn的金属间化合物.无铅钎料Sn-9Zn中稀土元素Ce的添加量为0.08%时,钎料焊点的力学性能最佳.     

Ni元素对Sn2.5Ag0.7Cu0.1RE/Cu无铅微焊点界面IMC和力学性能的影响

以Sn2.5Ag0.7Cu0.1RE无铅钎料为研究对象,借助扫描电镜和X衍射等检测方法研究了Ni元素对Sn2.5Ag0.7Cu0.1RE/Cu无铅微焊点界面IMC和力学性能的影响.结果表明,添加适量Ni元素能显著细化Sn2.5Ag0.7Cu0.1RE钎料合金初生β-Sn相和共晶组织,抑制焊点界面区(Cu,Ni)6Sn5金属间化合物的生长和表面粗糙度的增加,提高无铅焊点抗剪强度.当Ni元素添加量为0.1%时,钎料合金组织细小均匀,共晶组织所占比例较多;焊点界面IMC薄而平整,(Cu,Ni)6Sn5颗粒尺寸小,对应焊点抗剪强度最高为45.6 MPa,较未添加Ni元素焊点提高15.2%.     

合金元素对AgCuZn系钎料合金组织与性能的影响

通过向AgCuZn系钎料合金中添加适量的合金元素Sn,Ni,P,研究了不同元素含量的Sn,Ni,P对AgCuZn系无镉钎料组织性能的影响.结果表明,随着Sn元素含量的增加,钎料的润湿铺展性能整体呈上升趋势;P元素的加入可以降低液态钎料与试件间的表面张力,改善钎料的润湿性和流动性.显微组织分析表明,AgCuZn系钎料合金微观组织主要由富Cu相、CuZn化合物相、Cu5.6Sn化合物相、Cu40.5 Sn11化合物相和Ag的析出相组成,AgCuZn钎料合金中加入Sn元素后生成粗大的树枝晶,使钎料脆性增大;钎料合金中加入Ni元素,生成灰黑色的Ni3P化合物相,微观组织细化;P元素的加入生成灰色的Cu3P化合物相.     

添加微量稀土对SnBi基无铅钎料显微组织和性能的影响

研究了添加微量稀土对Sn58Bi基无铅钎料熔化温度、润湿性能、钎焊接头强度、高温时效前后IMC厚度的变化和显微组织的影响,并与添加一定量Ag对Sn58Bi钎料的试验结果做了比较.试验所用钎料为Sn58Bi,Sn58Bi0.5Ag,Sn58Bi0.1RE和Sn58Bi0.5Ag0.1RE,添加稀土为Ce基混合稀土.试验结果表明,添加微量稀土不仅抑制了Sn58Bi钎料高温时效引起的IMC的生长,而且细化了显微组织;微量稀土添加对钎料熔化温度没有明显影响,但能显著改善Sn58Bi钎料的润湿性能和接头强度,而且改善的程度优于添加微量Ag对Sn58Bi钎料的作用.     

水洗钎剂下SnAgCuRExNi与铜引线的润湿适配性

采用润湿平衡法,选用商用水洗钎剂,研究了镍添加量及钎焊工艺参数对Sn2.5Ag0.7Cu0.1RE钎料合金在铜引线上的润湿适配性. 结果表明,当Sn2.5Ag0.7Cu0.1RE钎料合金中镍添加量为0.05%时,钎料合金显微组织明显细化;当钎焊温度为255 ℃、钎焊时间为5 s、浸渍速度为20 mm/s、浸渍深度为3 mm的情况下, 其与φ0.6×30 mm的铜引线具有较好的润湿适配性,即具有较短的润湿时间,较小的润湿角,较大的润湿力,符合润湿力、润湿时间和润湿角的相关标准,完全满足现代表面组装技术对无铅钎料润湿性能的要求.     

Sn-2.5Ag-0.7Cu-0.1RE-xNi的润湿特性

采用润湿平衡法,选用商用水洗钎剂研究了Sn-2.5Ag-0.7Cu-0.1RE-x Ni钎料合金在Cu引线和Cu基板上的润湿特性。结果表明,当Ni添加量为0.05%~0.1%时,Sn-2.5Ag-0.7Cu-0.1RE钎料合金中在Cu引线上具有较短的润湿时间,较小的润湿角,较大的润湿力;在Cu基板上具有较小的润湿角和较大的铺展面积;焊点界面区Cu6Sn5厚度小而平整;其润湿特性满足现代表面组装技术对无铅钎料润湿性能的要求。     

稀土元素Nd对Sn-9Zn无铅钎料性能的影响

研究了添加稀土元素Nd对Sn-9Zn无铅钎料的润湿性能、显微组织和焊点力学性能的影响.结果表明,Nd元素的加入改善了钎料的润湿性能,质量分数为0.06%时,钎料的润湿力最大,润湿时间最短,润湿性能达到最佳.随着Nd元素的加入,钎料的基体组织得到细化,富锌相逐渐减少,当元素Nd的添加量大于0.06%时,钎料的显微组织中出现小块状稀土元素Nd和Sn的金属间化合物.无铅钎料Sn-9Zn中稀土元素Nd的添加量为0.06%时,剪切力和拉伸力达到最大,分别提高了19.6%和26.6%,力学性能最佳.     

Effects of in situ nickel particle addition on the microstructure and microhardness of Sn–Ag solder

Abstract

In this study, various amounts of Ni particles were added in situ to Sn–3·5 wt-%Ag lead free solder to form new composite solders. Copper substrates were then dipped into these solders and aged at 150°C for 0, 25, 225, or 1000 h. The microstructure and microhardness of the as solidified solder and the aged solder/copper couples were investigated. Experimental results revealed that the addition of Ni particles increased the microhardness of the composite solder. Ni additions of less than 3 wt-% yielded a microstructure of β-Sn grains surrounded by a eutectic mixture of Ag₃Sn and a Sn rich matrix. An intermetallic compound of Ni₃Sn₄ particles was dispersed throughout the eutectic. For 5 wt-%Ni addition, the Ni₃Sn₄ phase and the remaining Ni particles were agglomerated. In the case of copper substrate dipped with a thick layer of composite solder, water quenched and then aged at 150°C, the induced (Ni, Cu)₃Sn₄ particles coarsened and agglomerated. Additionally, the intermetallic (Cu, Ni)₆Sn₅ compound layer formed at the solder/Cu interface thickened with increasing Ni content.     

Influence of rare earth Ce addition on the microstructure,properties and soldering reaction of pure Sn

The influence of trace rare earth (RE) Ce addition on the microstructure, melting point and wettability of pure Sn as well as on the soldering reactions in Sn-xCe/Cu(Ni) solder joints was investigated. In bulk Sn-xCe solders, large β-Sn grains were observed with the Ce addition less than 0.2 wt%; while the β-Sn grain size decreased markedly when the Ce addition was 0.2 wt%, resulting in a refined microstructure. The addition of trace RE Ce had little effect on the melting temperature of the solders. Smaller wetting angles of Sn-xCe solders on both Cu and Ni substrates were measured when the samples were reflowed at a higher temperature. The Sn-0.2Ce solder owned the best wettability on Cu substrate. Scallop-like Cu₆Sn₅ intermetallic compound (IMC) grains formed at the Sn-xCe/Cu interfaces, while a continuous Ni₃Sn₄ IMC layer formed at each Sn-xCe/Ni interface. With the increase of Ce addition, the interfacial IMC grain size and the interfacial IMC layer thickness on both Cu and Ni substrates decreased gradually. The activity of Sn was lowered with the Ce addition, which depressed the growth of the interfacial IMC. In the current study, the Ce addition of 0.2 wt% exhibits the optimized performance.     

微量稀土镧钕对Bi5Sb8Sn力学性能影响

通过在Bi5Sb8Sn基体钎料上添加微量稀土镧钕形成Bi5Sb8SnRE新型钎料合金,研究了稀土镧钕对钎料合金力学性能的影响,同时对显微组织进行了分析.结果表明,稀土镧钕含量为0.2%时,Bi5Sb8SnRE合金抗拉强度和抗剪强度达到最大值,分别为58.30 MPa和15.50 MPa,合金抗拉强度和钎焊接头的抗剪强度较基体钎料Bi5Sb8Sn分别提高了44.2%和57.0%.显微组织分析表明,微量稀土镧钕的添加能显著细化该钎料的合金组织,改善合金的组织分布,提高钎料的力学性能;但当稀土含量超过0.2%时,稀土化合物的数量增多,钎料的力学性能下降.     

Ni-CNTs增强颗粒对Sn58Bi-0.1Er焊点组织与力学性能的影响

采用真空熔炼方法制备了不同Ni-CNTs含量的Sn58Bi-0.1Er钎料合金,研究不同Ni-CNTs含量对Sn58Bi-0.1Er复合钎料在Cu 基板上的润湿性能的影响,并对不同Ni-CNTs含量下接头界面处金属间化合物的组织形貌及接头的剪切性能进行了分析. 结果表明,当Ni-CNTs 增强颗粒的添加为0.01% ~ 0.05%(质量分数)时,复合钎料合金在铜板上的润湿性得到了提高,随着Ni-CNTs含量的进一步增加,复合钎料在铜板上的润湿性开始呈下降趋势;随着Ni-CNTs的加入,Sn58Bi/Cu界面金属间化合物由锯齿状的Cu₆Sn₅转变成薄层状的(Cu, Ni)₆Sn₅, Ni-CNTs增强颗粒的加入可以有效减小界面金属间化合物层的厚度;Ni-CNTs增强颗粒的加入提高了Sn58Bi/Cu接头的剪切力,当Ni-CNTs的添加量为0.1%时,接头的剪切力最高为432.86 N,较Sn58Bi-0.1Er钎料接头的剪切力提升了两倍以上. Ni-CNTs增强颗粒的添加有效地改善了Sn58Bi-0.1Er接头的力学性能.     

Ni元素含量对BiSbSnxNi钎料润湿性能和抗剪强度影响

研制开发高温无铅软钎料一直是钎焊领域一大难题.熔点为270℃左右的Bi5Sb8Sn钎料因润湿性能和抗剪强度达不到要求而受到限制.通过在Bi5Sb8Sn中添加不同含量Ni元素形成新型BiSbSnNi四元合金,来改善Bi5Sb8Sn合金的润湿性能和力学性能.结果表明,尽管Ni元素的添加使BiSbSnxNi钎料合金铺展面积均较基体钎料差.但Ni元素的最佳添加量为2%时,可以改善钎料中金属间化合物的生成,能够增大钎料的铺展面积.当Ni元素含量为3%时,钎料合金的抗剪强度最高.在Ni元素含量为4%时,IMC厚度明显增加,且出现条状的富铋相,对钎料焊接接头的抗剪强度产生不利影响.     

Sn-9Zn-xPr钎料钎焊性能及显微组织

研究了稀土元素Pr的添加量对Sn-9Zn无铅钎料的润湿性能、显微组织和焊点力学性能的影响.结果表明,镨的加入不仅改善了钎料的润湿性能和抗氧化性能,而且细化了钎料基体中的富锌相,使得界面组织更为稳定,有利于焊点可靠性的改善;Sn-9Zn无铅钎料中镨的添加量为质量分数0.08%时,钎料的润湿性能最佳,综合性能最好;当镨的添...     

Investigation of small Sn–3.5Ag–0.5Cu additions on the microstructure and properties of Sn–8Zn–3Bi solder on Au/Ni/Cu pads

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.     

添加Sn及热处理对Co38Ni34Al28-xSnx磁性形状记忆合金显微组织和显微硬度的影响（英文）

在Co38Ni34Al28合金体系中添加 Sn,研究Sn含量及不同的热处理温度（1373 K,1473 K,1573 K）下,保温2h对Co38Ni34Al28-xSnx（x=1,2,3）合金显微组织和硬度的影响。结果表明,添加适量的Sn使合金中γ相组织减少;在1573K保温2h后,在室温下获得部分马氏体组织;当Sn 替代 2%Al 时,其显微组织中马氏体组织的比例较高。随着Sn含量的增多和热处理温度的升高,合金的硬度也随着增大。另外,合金马氏体的逆相变温度在Sn含量为1%和2%时升高,在Sn含量为3%时反而降低。     

纳米Ti颗粒对三维封装Sn互连材料组织与性能影响

Sn作为三维封装芯片堆叠瞬时液相键合主要互连材料之一,本文研究了纳米Ti颗粒对三维封装Sn互连材料组织和性能的影响。结果表明：微量的纳米Ti颗粒可以提高Sn膏在铜基板表面的润湿铺展面积,显著增加Sn焊点的拉伸力和剪切力,但是过量的Ti纳米颗粒会恶化焊点的力学性能。基于Ti纳米颗粒含量优化分析证实纳米Ti颗粒的最佳添加量为0.1wt.%左右。对Cu/Sn/Cu和Cu/Sn-0.1Ti/Cu三维封装模拟件进行分析,发现Cu/Sn-0.1Ti/Cu焊点界面金属间化合物的厚度明显小于Cu/Sn/Cu,证实0.1wt.%可以显著降低金属间化合物的生长速度。 基于有限元模拟,发现0.1wt.%Ti可以显著降低三维封装互连焊点的应力-应变,提高三维封装互连焊点的可靠性。