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.
The following study is motivated by the need to capture the elasto-viscoplastic behavior of a “real” industrial power module lead-free solder joint. In this work, we carried out a numerical design of experiments in order to forecast the ability of an experimental bending system to identify the specimen material properties. As a proof of principle, the micro-mechanical elastic behavior of power module...
Atomic diffusion in soldering process leads to growth and stress developed in the intermetallic compound layer in solder joints. The stress and morphological evolution of the intermetallic compound layer, which is driven by the stress, result in degradation of mechanical performance of solder joints. Microstructure of the intermetallic compound layer in solder joints is modeled. The model consists...
This study examines evolution characteristics of inelastic strains and materials damage in Sn-4Ag-0.5Cu (SAC405) solder joints of a BGA package under cyclic mechanical stressing. For this purpose, a finite element model of the assembly under four-point bend test set-up is employed. Strain rate-dependent response of the solder is represented by Anand model. Progressive damage in the solder joint is...
Thus far, there is a severe lack of understanding about interfacial fracture and impact behavior of the microscale lead-free solder interconnects. In this study, the finite element simulation and analytical method were used to characterize the interfacial fracture and impact behavior at the interfaces of the microscale Sn-Ag-Cu solder joints. The intersection of a linear microcrack tip upon Sn-Ag-Cu...
In this paper, the investigation focuses on the copper stud bump solder joint thermal-mechanical reliability. The copper stud bump processing is simulated by FEM software Ansys/Ls-dyna, and then the relationship between the copper stud bump and processing parameters (bonding force, ultrasonic power, bonding time and bonding temperature) is studied. Based on the simulation result, the dimension of...
This paper presents mining the worst thermal fatigue life of solder joints on chip components used in vehicle electronics. The authors proposed an isothermal fatigue test method using real size solder joints to get the fatigue properties. The Manson-Coffin's law given by this method could improve the agreement between the simulation model and experimental results. Based upon the Manson-Coffin's law...
A strain-controllable dynamic bending method on WLCSP has been proposed in this paper. In order to identify the principle factor among the effects of stiffness attributed by different board level structures, the 0.4 mm pitch WLCSP packages with Sn-4.0Ag-0.5Cu solder ball are used. This combination of WLCSP is considered to have the high stiffness in the structure. It is also shown that there are interactions...
In this paper, the damage fracture of solder joints in board level electronic package subjected to drop impact loadings was numerically simulated by the finite element method and the cohesive zone model. The solder-Cu pad interface was modeled by cohesive zone elements. The results show that fracture initiates at the edge of the PCB side and the damage of solder joint is affected greatly by the used...
The properties of lead-free solders such as Sn3.8Ag0.7Cu are less understood than traditional Sn-Pb solders, as well as the factors affecting these material properties. Therefore, the present paper focuses on determination of stress-strain properties for both small-scale solder joints and for bulk solder for three different strain rates. The paper also analyses the obtained experimental results, and...
Lap-shear tests were combined with elastic-viscoplastic constitutive modeling to study the shear behavior of Sn3.8Ag0.7Cu (SAC) solder ball joints. In the shear rate range of 0.005 mm/s to 0.7 mm/s, the peak shear force was attained an optimal rate (labeled as vo), around 0.3 mm/s. On either side of vo, the shear fracture behavior was quite different. Cross-section examinations of the remaining solder...
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.