The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This study, mainly emphasis on effects of solder volume on interfacial diffusion kinetics and mechanical properties of Sn/Cu microbump solder joints. Different thicknesses i.e. 12 μm Sn (electrodeposited) and 100 and 200μm Sn is screen printed over 14 μm thickness Cu under bump metallization (UBM). The diameter of Cu UBM used in this study is 50, 110 and 240μm respectively. Solder joints are subjected...
Polarization characteristics of the processes of Cu, Co and Cu-Co alloy electrodeposition from ammonium sulphate containing supporting electrolyte and their morphologies are investigated as a function of Cu2+ and Co2+ ions concentrations. By application of energy dispersive spectral analysis, (EDSA), including X-Ray analysis and SEM, data are obtained about the morphology and element composition of...
A Cu/Ni UBM and Sn-2.5Ag lead-free solder for 20 μm pitch micro-bump was successfully fabricated via consecutive electroplatings of Cu, Ni, and binary SnAg. Materials characterizations such as Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Electron Probe Micro-analyzer (EPMA), and X-ay Photoelectron Spectroscopy (XPS) were carried out to obtain relevant materials properties. We observed...
The texture as well as epitaxial growth of intermetallic compounds (IMCs) are becoming important issues, due to increases in IMCs-solder ratios in the development of micro-bumping. (Cu, Ni)6Sn5 formed on Ni substrate didn't simply grow in an unexpected manner, but did so, producing a spectacular morphology. Even in the presence of very few Ni atoms dissolved in (Cu, Ni)6Sn5, a strongly preferential...
The influence of the standoff height, pad size and isothermal aging on the microstructure and shear fracture behavior of Cu/Sn-3.0Ag-0.5Cu/Cu BGA structured interconnects were investigated using the lap-shear test. The experimental results show that the thickness of intermetallic compounds (IMC) layer at the solder/Cu interface increases with decreasing standoff height of the joints. The size of Kirkendall...
The effects of the rare earth Ce element on melting temperature, wettability of Sn-0.3Ag-0.7Cu low-Ag lead-free solder and the intermetallic compounds morphologies of Sn-0.3Ag-0.7Cu-XCe/Cu were investigated. The addition of the Ce element has an unconspicuous effect on decreasing the melting temperature of Sn-0.3Ag-0.7Cu solder. The results indicate that the addition of Ce element increases the wettability...
The interfacial reactions between (001) Ni single crystal and high-Sn solders were compared with those of polycrystalline Ni. The morphology of interfacial intermetallic compound (IMC) grains formed between (001) Ni single crystal and high-Sn solders (pure Sn, Sn-0.7Cu, Sn-0.7Cu-0.1Ni, Sn-1.5Cu and Sn-1.5Cu-0.1Ni, all in wt. %) at 250 °C and 300°C for various durations was investigated. Regular arrangement...
The current study revealed that the growth kinetics and the interfacial reaction of the Cu/Sn/Ag couples with different thickness solder. For the Cu/Sn/Ag couples, plate-type Ag3Sn was firstly formed at the Sn/Cu interface rather than at the Sn/Ag interface for the Cu/Sn/Ag couple at the initial state of the reflow procedure when the solder thicknesses is 150 μm or 300 μm. Besides, the microstructure...
Ag-Cu nanoalloy has been synthesized directly in solution. The composition, morphology and structure of the Ag-Cu nanoalloys were characterized by XRD, TEM, EDS and SEM. The morphology of Ag-Cu nanoalloys appears small, uniform, and spherical. The size distribution mainly focuses on 80nm~90nm. An average composition is Ag48.9Cu51.1, which is within experimental error of the nominal 1:1 stoichiometry...
In this paper, the concept of a defect phase diagram is introduced which quantifies the effects of Cu and Pb additions to electrodeposited Sn films on surface defect formation, including but not limited to the formation of Sn whiskers. Transitions were observed in both the defect densities and the morphologies of hillocks and whiskers as Cu and Pb film compositions were systematically varied. Changes...
In natural seawater, pure aluminum develops oxide layer which forms a barrier, protecting against corrosion. Alloying with other elements prevents the development of oxide layer by introducing localized galvanic cells. Different aluminum alloys exhibit different electrochemical behavior. The scope of the project was to study the effects of the addition of Zn, Sn, Mg, Cu, Fe, and Si on the morphology...
Ball grid array (BGA) solder interconnecting is one of the key technologies in electronic packaging and assembly. Legislation of lead-free process has made the application of lead-free solder become wider in electronic products. Compared to the lead-tin solder, the relatively higher melting points of most lead-free solders call for a higher reflow temperature. Thus conventional integral-heating process...
This work compared the interfacial reactions of single crystal Cu and polycrystalline Cu with the high-Sn solders. The morphology aspects of Cu6Sn5 intermetallic compound (IMC) grains formed between (001) single crystal Cu and high-Sn solder bath (pure Sn, Sn-0.7Cu, Sn-3Cu) at 250degC and 300degC for different durations ranging from 10 s to 10 min were investigated. The Cu6Sn5 grains formed in all...
It is found that the morphologies and orientations of Cu6Sn5 can be well controlled through designing orientations of Cu single crystal substrates. On (001) and (111) Cu single crystals, Cu6Sn5 grains display regular prism-type morphology and align either along two perpendicular directions or along three directions having an angle of 60deg between each other. By electron backscatter diffraction (EBSD)...
The wetting behavior of Sn-Ag-Cu solder ball on nickel pad has been studied. SEM and EDX were employed to analyze the solder joint interfacial microstructure. Three zone-reactive wetting ring structure was found at the interface. To further study this kind of structures, solder ball attachment (SBA) and surface mount technology (SMT) were performed to prepare more samples. Experimental results show...
Summary form only given. Since the very beginning the laser-assisted methods have become of critical importance for the metal deposition. Various laser techniques allow metal precipitation on the different kinds of the materials. One of them is the Laser-induced chemical liquid phase deposition (LCLD), which is considered among the others to be the most promising and efficient. Indeed, the LCLD method...
The changes of morphology and growth tropism of inter-metallic compound (IMC) and IMC growth rate at lead-free solders/Cu interface of solder joints often limit the reliability of the entire package during service. Furthermore, during thermal-shearing cycling process, the thickness of IMC at the interface grows significantly and growth tropism of IMC changes, resulting in in-service evolution of the...
The Cu pillar is a thick under bump metallurgy (UBM) structure developed based on the consideration of alleviating current crowding in a flip-chip solder joint in operation conditions. We present in this work electromigration reliability and morphologies of Cu pillar flip-chip solder joints formed by joining Ti/Cu/Ni UBM with largely elongated Cu at ~62 mum onto Cu substrate pad metallization through...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.