This Note describes the suitability of a number of techniques of potential use in studying cracking in lead-free solder joints, and hence their use in assessing joint lifetimes. Cracks induced into solder joints of chip resistors on FR4 substrates, were studied using micro-sectioning, dye penetration, mechanical test and thermal conductivity techniques. The work previously reported [1] has been...

For electronic products, interconnect failures may occur due to mechanisms such as fatigue, creep, corrosion, and mechanical over-stress. Regardless of the failure mechanism, interconnect degradation often starts at a surface and propagates inward. DC resistance, which has been used by the electronics industry to monitor the reliability of board level interconnects, does not offer an adequate m...

Board-level solder joint reliability is very critical for handheld electronic products during drop impact. In this study, board-level drop test and finite element method (FEM) are adopted to investigate failure modes and failure mechanisms of lead-free solder joint under drop impact. In order to make all ball grid array (BGA) packages on the same test board subject to the uniform stress and str...

Title of Dissertation: DEVELOPMENT OF MOIRÉ INTERFEROMETRY FOR REAL-TIME OBSERVATION OF NONLINEAR THERMAL DEFORMATIONS OF SOLDER AND SOLDER ASSEMBLY Seungmin Cho, Doctor of Philosophy, 2005 Dissertation Directed By: Associate Professor Bongtae Han, Department of Mechanical Engineering An experimental apparatus using moiré interferometry is developed to characterize the thermo-mechanical behavio...

In this paper, efficient techniques for solder joint inspection have been described. Using three layers of ring shaped LED's with different illumination angles, three frames of images are sequentially obtained. From these images the regions of interest (soldered regions) are segmented, and their characteristic features including the average gray level and the percentage of highlights referred t...

This study simulated the performance of Cu-cored solder joints in microelectronic components subjected to the extreme thermal cycling conditions often encountered in the automobile industry by comparing the thermal cycling behavior of Cu-cored solder joints containing two different coating layers of Sn– 3.0Ag and Sn–1.0In with that of a baseline Sn–3.0Ag–0.5Cu solder joint under a severe temper...

Au (0.05 μm) 69.4 μm Electromigration may affect the reliability of flip-chip solder joints. Eutectic solder is a two-phase alloy, so its electromigration behavior is different from that in aluminum or copper interconnects. In addition, a flipchip solder joint has a built-in currentcrowding configuration to enhance electromigration failure. To better understand electromigration in SnPb and lead...

The significant increase in metal costs has forced the electronics industry to provide new materials and methods to reduce costs, while maintaining customers' high-quality expectations. This paper considers the problem of most electronic industries in reducing costly materials, by introducing a solder paste with alloy composition tin 98.3%, silver 0.3%, and copper 0.7%, used for the constructio...

In the continuing effort to shrink the electronics components and assemblies, the need for streamlined production processes and quality assurance is emerging stronger than ever. Surface Mounted Devices (SMD) is one of the breakthrough techniques that drove printedcircuit board production to a new level, increasing substantially the component density and reducing the size of produced circuits. Q...

0026-2714/$ see front matter 2010 Elsevier Ltd. A doi:10.1016/j.microrel.2010.06.013 * Corresponding author. Tel.: +852 2788 7130; fax: E-mail address: [email protected] (Y.C. Chan Nano-sized, nonreacting, noncoarsening Al2O3 particles have been incorporated into eutectic Sn–Zn solder alloys to investigate the microstructure, hardness and shear strength on Au/Ni metallized Cu pads ball grid...