The quality of surface mount technology (SMT) product solder joint was key factor for SMT products. In this paper, for chip components, a fuzzy fault diagnosis principle of SMT products was analyzed. And the total framework of fault diagnosis system was built based on solder joint shape theory. Geometrical shape parameters which reflected chip components solder joint quality were analyzed and d...

In this paper, the Moir e interferometry technique is used to measure the in situ displacement evolution of lead-free solder joint under electric current stressing. Large amounts of deformation were observed in the solder joint under high density (above 5000 A/cm) current stressing. The deformation was found to be due to electromigration in the solder joint and an electromigration constitutive ...

There is an increasing demand for replacing tin-lead (Sn/Pb) solders with lead-free solders in the electronics industry due to health and environmental concerns. The European Union recently passed a law to ban the use of lead in electronic products. The ban will go into effect in July of 2006. The Japanese electronics industry has worked to eliminate lead from consumer electronic products for s...

In this paper, Moir e interferometry technique is used to measure the in situ displacement evolution of lead-free solder joint under electric current stressing. Large deformation was observed in solder joint under high density (10 A/cm) current stressing. The deformation was found to be due to electromigration in the solder joint. An electromigration constitutive model is applied to simulate de...

The presence of an 'underfill' encapsulant between a micro-electronic device and the underlying substrate is known to substantially improve the thermal fatigue life of flip-chip solder joints, primarily due to load-transfer from the solder to the encapsulant. In this study, a new single joint-shear (SJS) test, which allows the measurement of the strain response of an individual solder ball duri...

Solder joint fatigue failure is a serious reliability concern in area array technologies, such as flip chip and ball grid array packages of integrated-circuit chips. The selection of different substrate materials could affect solder joint thermal fatigue life significantly. The mechanism of substrate flexibility on improving solder joint thermal fatigue was investigated by thermal mechanical an...

The fracture of SAC305 solder was investigated as a function of strain rate using Cu-solder-Cu double cantilever beam (DCB) specimens joined with a series of 2 mm long discrete solder joints of 150 m thickness. The joints were then fractured with various strain rates under mode I and mixed-mode loading conditions. The failure of each joint in the DCB was accompanied by a sharp drop in the appli...

The coupling effect of interfacial reactions between two pads in Ni-SnAg-Cu and Au/Ni/Cu-SnAg-Cu solder joints was investigated in this paper. After reflow soldering, a large amount of Cu can diffuse across the solder joint to the opposite pad to form (Cu,Ni)6Sn5 IMC on the Ni pad in Ni-SnAg-Cu solder joint. A little Ni can also be detected in Cu6Sn5 layer, which contains some trapped solder, o...

Due to the inherent nature of flip-chip assembly, the solder joints lie beneath the device and therefore are not amenable to visual inspection. Hence, it is important at the design stage to ensure that solder defects such as joint separation or joint shortening do not occur in the assembly. As a first step, the solder joint is modeled using a level-set approach. Unlike conventional fronttrackin...

Introduction Intermetallic compounds (IMCs) are generally considered a bad thing in solder joints, though this is not always the case. Excessive IMCs in solder joints are a bad thing since they significantly alter both the composition and the mechanical performance of the solder joint. Interfacial IMC layers can be an indication of the quality of the solder joint and the lack of them would indi...