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—Digital image correlation and cross polarizer, optical microscopy were used to quantify the deformation behavior under deep thermal cycling of near eutectic SnAgCu (SAC) solder in board level interconnects. Maps with sub micron spatial resolution of the strain levels and von Mises strain were produced for selected cross sections. Large spatial variations(More)
Optical microscopy was used to discern the different grain orientations and grain boundaries on the polished cross-sections of near-eutectic lead-free board-level SnAgCu (SAC) solder interconnects. Strain distributions with submicron accuracy of the deformations on the cross-sections of the solder interconnects were measured when the package was subjected(More)
A noncontact, fast, accurate, low-cost, broad-range, full-field, easy-to-implement three-dimensional (3D) shape measurement technique is presented. The technique is based on a generalized fringe projection profilometry setup that allows each system component to be arbitrarily positioned. It employs random phase-shifting, multifrequency projection fringes,(More)
We propose an advanced thermal-moisture analogy scheme to cope with the inherent limitations of the existing analogy schemes. The new scheme is based on the experimentally observed unique hygroscopic behavior of polymeric materials used in microelectronics ; i.e., the saturated concentration is only a function of relative humidity regardless of temperature.(More)
The peak value of out-of-plane displacement of printed circuit board (PCB), when it is subjected to drop impact, is a major concern to electronic manufacturers as it relates to the maximum stress causing failure for the solder balls. In this work, the full-field dynamic responses of printed circuit boards (PCBs) of product level are measured and analyzed in(More)
(2015),"Integrated hygro-swelling and thermo-mechanical behavior of mold compound for MEMS package during reflow after moisture preconditioning" (2015),"Effect of wire diameter and hook location on second bond failure modes", If you would like to write for this, or any other Emerald publication, then please use our Emerald for Authors service information(More)
— The stresses due to moisture saturation on microelectromechanical systems (MEMS) sensor devices after exposure to temperature cycling have been addressed. Moisture-, temperature-, and time-dependent material property of molding compounds for the MEMS devices were characterized. To determine the coefficient of hygroscopic swelling of a molding compound and(More)
This paper develops an assessment methodology based on vibration tests and finite element analysis (FEA) to predict the fatigue life of electronic components under random vibration loading. A specially designed PCB with ball grid array (BGA) packages attached was mounted to the electro-dynamic shaker and was subjected to different vibration excitations at(More)
—In this paper, packaging-induced stress effects are assessed for microelectromechanical systems (MEMS) sensors. A packaged MEMS sensor may experience output signal shift (offset) due to the thermomechanical stresses induced by the plastic packaging assembly processes and external loads applied during subsequent use in the field. Modeling and simulation to(More)