Electromigration is a major road block in the pursuit of nanoelectronics and next generation power electronics. The current density in the state-of-the-art microelectronics solder joints is about 10 A/cm. In the next generation nanoelectronics solder joints this current density is expected to increase by an order of magnitude, at least. In this paper, a new damage mechanics formulation is imple...

smaller devices and reduced form factors with time, resulting in new challenges. Reduction in device and interconnect solder bump sizes has led to increased current density in these small solders. Higher level of electromigration occurring due to increased current density is of great concern affecting the reliability of the entire microelectronics systems. This presentation reviews electromigra...

This paper investigates methodologies for locating and identifying the components on a printed circuit board (PCB) used for surface mount device inspection. The proposed scheme consists of two stages: solder joint extraction and protective coating extraction. Solder joints are extracted by first detecting all the highlight areas, and then recognizing and removing the invalid highlight areas whi...

To better understand the effect of repeated reverse stress in solder joints, a new testing method was developed. Tin-silver solder joints were fabricated, constrained between Cu blocks, and then subjected to repeated shear loading in a tensile tester. Constant strain amplitudes were applied to simulate service conditions. However, large loads were used to accelerate the damage accumu­ lation. M...

This program investigates the fluid dynamics and simultaneous solidification of molten solder droplets impacting on a flat substrate. The problem of interest is directly relevant to the printing of microscopic solder droplets in surface mounting of microelectronic devices. The study consists of a theoretical and an experimental component. The theoretical work uses axisymmetric Navier-Stokes mod...

The influence of alloy composition of lowmelting Sn-Bi-Cu lead-free solder alloys on mechanical properties and solder joint reliabilities were investigated. The mechanically optimum alloy composition is Sn-40Bi-0.1Cu (mass%). The addition of 40mass%Bi improves the ductility and restrains the fillet-lifting, which are problems of lead-free solders with Bi. The addition of copper improves both th...

In this study the intermetallic (IMC) thickness of Sn-Pb, Sn-Zn and Sn-Zn-Bi solders on copper (Cu) substrate were measured at different temperatures using reflow methods. Cu6Sn5 intermetallic phase was detected between Sn-Pb solder and Cu substrate. The -Cu5Zn8 phase was detected between Sn-Zn and Sn-Zn-Bi lead-free solders with Cu substrate. The thickness of the intermetallics increases with ...

The failure modes of flip chip solder joints under high electrical current density are studied experimentally. Three different failure modes are reported. Only one of the failure modes is caused by the combined effect of electromigration and thermomigration, where void nucleation and growth contribute to the ultimate failure of the module. The Ni under bump metallization–solder joint interface ...

In order to solve tiny defect detection for solder balls in high-density flip-chip, this paper proposed feasibility study on the effect of detectability as well as classification based on eddy current pulsed thermography (ECPT). Specifically, numerical analysis of 3D finite element inductive heat model is generated to investigate disturbance on the temperature field for different kind of defect...