共查询到19条相似文献,搜索用时 156 毫秒
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In焊料由于其优越的可塑性以及优良的导电、导热特性,被广泛用于半导体激光器(LD)的封装。但是In焊料遇空气易氧化,尤其在焊接加热的过程中,氧化现象更加明显,因此一般当天制备当天使用。为防止氧化,可以在In焊料表面镀一层Ag或Au作为保护层,因为Ag成本较Au低,可作为首选的保护层。关于In-Ag合金性能的研究已有过相关报道,但关于In-Ag合金的表面形貌及Ag层厚度对内部In的影响的报道还很少。文章通过扫描电子显微镜、XRD对不同样品进行了表面和成分的分析,得到了关于Ag对内部焊料的影响以及不同冷却速率下焊料的表面形貌。 相似文献
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大功率半导体激光器高可靠烧结技术研究 总被引:2,自引:0,他引:2
近几年大功率半导体激光器的应用领域越来越广,许多应用领域都要求半导体激光器能够高可靠性工作.工作焊接质量直接影响着大功率半导体激光器的可靠性,焊接缺陷会导致激光器迅速退化.目前国内普遍采用的铟焊料和锡铅焊料都是软焊料,焊层有形成晶须和热疲劳等可靠性问题.为提高烧结可靠性,采用了金锡焊料烧结激光器新技术.金锡焊料是硬焊料,焊接强度高,抗疲劳性好,对金层无浸蚀现象.通过实验研究掌握了金锡焊料的制备和烧结技术,并与铟焊料、锡铅焊料进行了对比实验.实验结果显示采用金锡焊料烧结激光器可获得更好的性能,是提高半导体激光器可靠性的有效途径. 相似文献
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半导体激光器焊接的热分析 总被引:1,自引:0,他引:1
为了解决大功率半导体激光器的散热问题,利用有限元软件ANSYS,采用稳态热模拟方法,分析了半导体激光器内部的温度分布情况,对比分析了In、SnPb、AuSn几种不同焊料烧结激光器管芯对激光器热阻的影响。由模拟结果可见,焊料的厚度和热导率对激光器热阻影响很大,在保证浸润性和可靠性的前提下,应尽量减薄焊料厚度。另外,采用高导热率的热沉材料和减薄热沉厚度可有效降低激光器热阻。在这几种焊接方法中,采用In焊料Cu热沉焊接的激光器总热阻最小,是减小激光器热阻的最佳选择。通过光谱法测出了激光器热阻,验证了模拟结果,为优化激光器的封装设计提供了参考依据。 相似文献
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烧结温度对AuSn焊料薄膜及封装激光器性能的影响 总被引:1,自引:0,他引:1
采用不同温度对Au80Sn20共晶合金焊料进行烧结实验,研究了AuSn焊料薄膜在烧结后的形貌、物相组成以及对封装激光器的性能影响等.焊料在烧结后形成ξ相Au5Sn和δ相AuSn两种金属间化合物,随着烧结温度的上升,两相晶粒均明显长大,而ξ相Au5Sn趋向于形成枝晶.较低温度下烧结的焊料表面粗糙度较高,不利于激光器管芯的贴装.高温过烧焊料薄膜的导电导热性能有少许提升,对封装激光器管芯的功率没有明显影响,但焊料薄膜中残余应力较高,使激射波长有所蓝移.该结果将为AuSn焊料的烧结参数优化和硬焊料封装激光器的性能分析提供参考和指导. 相似文献
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半导体激光器封装中热应力和变形的分析 总被引:2,自引:0,他引:2
为了解决半导体激光器封装的热应力和变形问题,利用有限元软件ANSYS对SnPb、In、AuSn三种焊料焊接激光器管芯的情况分别进行了模拟,得到了相应的热应力大小和变形情况,分析了焊料和热沉对激光器热应力和变形的影响.对比了这几种不同封装方法的激光器发光区图像的弯曲程度,验证了模拟结果.由模拟和实验结果可见,采用In焊料是减小激光器热应力和变形的最佳选择.另外,适当增加热沉厚度,选择热匹配的材料,焊接时进行预热,可减小激光器的热应力和变形.通过模拟和实验分析,提出了减小热应力和变形的方法,为优化激光器的封装设计提供了参考依据. 相似文献
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The high thermal conductivity, light weight, and low cost of aluminum (Al) make it a promising material for use in high-power electronic packaging. The challenges are its high coefficient of thermal expansion (CTE) of 23 × 10?6/°C and difficulty in soldering. In this research, we surmounted these challenges by bonding large Si chips to Al boards using fluxless Sn and Ag-In processes, respectively. Despite the large CTE mismatch, the bonded structures were strong as determined by fracture force measured by shear test machine. The reference is the fracture force specified in MIL-STD-883H method 2019.8. The microstructure and composition of the joints were examined using scanning electron microscopy (SEM) and energy-dispersive x-ray (EDX) analysis. The resulting Sn joint is almost pure Sn with thin intermetallic layer. The Ag-In joint consists of Ag/(Ag)/Ag2In/(Ag)/Ag that has a melting temperature higher than 695°C even though the bonding process was performed at 180°C. These bonding processes are entirely fluxless. The fluxless feature greatly helps reduce voids in the joints, which in turn increases the joint strength. These preliminary but encouraging results should open up new applications of Al boards in electronic packaging where Al was avoided because of its high CTE and difficulty in bonding. 相似文献
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N. P. Klochko G. S. Khrypunov N. D. Volkova V. R. Kopach V. N. Lyubov M. V. Kirichenko A. V. Momotenko N. M. Kharchenko V. A. Nikitin 《Semiconductors》2013,47(6):856-864
The conditions of the bonding of silicon multijunction solar cells with vertical p-n junctions using Ag-In solder are studied. The compositions of electrodeposited indium films on silicon wafers silver plated by screen printing and silver and indium films fabricated by layer-by-layer electrochemical deposition onto the surface of silicon vertical diode cells silver plated in vacuum are studied. Studying the electrochemical-deposition conditions, structure, and surface morphology of the grown layers showed that guaranteed bonding is provided by 8-min heat treatment at 400°C under the pressure of a stack of metallized silicon wafers; however, the ratio of the indium and silver layer thicknesses should not exceed 1: 3. As this condition is satisfied, the solder after wafer bonding has the InAg3 structure (or InAg3 with an Ag phase admixture), due to which the junction melting point exceeds 700°C, which guarantees the functioning of such solar cells under concentrated illumination. 相似文献
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Lead-free solders have high Sn content and high melting temperature, which often cause excessive interfacial reactions at the interface. Sn3.5Ag0.5Cu lead-free solder alloy has been used to identify its interfacial reactions with two-metal layer flexible substrates. In this paper we investigate the dissolution kinetics of Sn3.5Ag0.5Cu solder on electrolytic Ni/electroless NiP layer. It is found that during 1 min of reflow electroless NiP layer dissolves slightly lower than the electrolytic Ni due to the barrier layer formation between the intermetallic compounds (IMCs) and electroless NiP layer. Faster nucleation of IMCs on the electrolytic Ni layer is proposed as the main reason for higher initial dissolution. The appearance of P-rich Ni layer acts as a diffusion barrier layer between the solder and electroless NiP layer, which decreases the dissolution rate and IMCs growth rate than that of the electrolytic Ni layer, but weaken the interface and reduces the ball shear strength and reliability. After acquiring certain thickness P-rich Ni layer breaks and increases the diffusion rate of Sn and as a consequence both the IMCs growth rate and dissolution rate also increases. It is found that 3 μm thick electroless NiP layer cannot protect the Cu layer for more than 120 min at 250 °C. In electrolytic Ni shear strength does not change significantly and lower dissolution rate and more protective for Cu layer during long time molten reaction. 相似文献
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《Microelectronics Reliability》2015,55(11):2371-2381
This paper reviewed the existing damage evolution models in the literature for solder layer in microelectronics and then proposed a two dimensional approximate time dependent damage indicator model for Sn3.5Ag type lead free solder layer in power electronic module application. The proposed time dependent damage indicator model is influenced by inelastic strain from microstructural evolution Anand viscoplastic model. The experimental evaluation of parameter values of the proposed damage indicator model was not feasible. Hence, we adopted a numerical approximation methodology to extract the parameter values of the damage model. A MatLab code was generated to simulate the stress versus strain curve of the solder layer during the thermal variance loading. A data from public domain for crack initiation and crack propagation of SnAg solder layer was also utilised to estimate the parameter values of damage indicator model. The developed approximate time dependent damage model was numerically compared with a damage model in the literature based on Coffin Manson and Paris law fatigue model for prediction accuracy. 相似文献
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《Components and Packaging Technologies, IEEE Transactions on》2008,31(4):875-879
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Sn-Ag基无铅钎料Nd:YAG激光重熔界面研究 总被引:2,自引:0,他引:2
通过Nd∶YAG激光重熔和热风二次重熔试验,得到了Sn3.5Ag和Sn3.0Ag0.5Cu无铅钎料球在Cu焊盘的钎料凸台.利用扫描电子显微镜分别分析了激光重熔和热风二次重熔后两种无铅钎料与铜焊盘界面反应及组织形貌,并对激光一次重熔无铅钎料凸台进行了剪切试验,观察了凸台的剪切断口.结果表明,在合适的激光功率和加热时间条件下能够获得成形良好的无铅钎料凸台,Sn3.5Ag和Sn3.0Ag0.5Cu两种无铅钎料与Cu焊盘所产生的界面化合物主要为Cu3Sn和Cu6Sn5,凸台界面反应组织形貌以及剪切承载力与激光功率和加热时间密切相关,而且激光重熔形成的界面化合物影响热风二次重熔界面的组织形貌. 相似文献
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The physical properties, solderability, and creep-rupture life of the nanosized Ag particle-reinforced Sn-Pb composite solder
were investigated. The experimental results indicate that the composite solder possesses good electrical conductivity as well
as good solderability. Compared to the eutectic 63Sn-37Pb solder matrix, the nanosized Ag particle-reinforced composite solder
improved the creep resistance and significantly enhanced the creep-rupture life of its solder joints. The fracture surface
revealed a mixture of ductile and brittle fracture features. 相似文献
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Thermodynamics of the Sn-In-Ag solder system 总被引:3,自引:0,他引:3