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To predict the reliability life for SnPb solder and Ag‐Pd bond pad metallization. The aim of selected artificial aging using temperature shock test (TST) and high temperature storage test (HTS). These tests are produced in a short time, the same deterioration in solder joint strength that would occur by natural aging in the actual field condition of up to 10 years or 5,000 h service life.

This paper using Arrhenius model describes the results of TST and HTS. The TST is aimed to verify the resistance of the assembly to cyclic temperature loading. The HTS test is aimed to check the effect of inter‐diffusion between solder and component and substrate finish, on the mechanical strength of the joints. The paper is organized in four sections: introduction, experimental procedure, experimental results and discussion, conclusion and recommendation.

The accelerated aging procedures used in this study had successfully modified mainly the outer surface and the interface between a solderable coating and the base metal. The tests that rely on higher temperature increase the diffusivity and the reactivity of the species and so modify internal interfaces such as the intermetallic compound layer, as well as the surface oxide layer. This has provided an effective screening test in understanding the reliability field performance.

For future work it is recommended to run HTS at 175C to validate the estimate for the effective activation energy for diffusion. Next, perform scanning electron microscopy & energy dispersive X‐ray (SEM/EDX) analysis to compare results at 150C for SMD components and studs and explain the different behaviour. Finally, continue T‐shock testing to 2000 cycles.

This has provided an effective screening test in understanding the reliability field performance.

This paper provides a cost effective and practical procedure in screening test for SnPb Solder and Ag‐Pd bond pad metallization. It is an effective solution to electronic manufacturing industry.

It was observed that “no solder” or “skipped solder” defects occurred on a particular printed circuit board assembly product during wave soldering. Investigations were carried out to find out the cause of this defect and to recommend an optimal hot air level coating thickness. To evaluate whether thicker plating helps to produce better solderability, new printed circuit boards with an average plating thickness of 4.27 μm were sent for solderability testing. This increase in plating thickness resulted in no defects in the solderability test. This is in contrast to the current printed circuit board that had a no/skipped solder defect rate of 1,433 ppm due to the thinner plating thickness which was in the region of 2.26 μm. In summary, the investigations made have revealed imperfections in the pad plating, and it is recommended that a thicker or more even plating is achieved during the hot air levelling process at the printed circuit board manufacturing site so as to eliminate no/skipped solder defects that are induced by this printed circuit board deficiency.

In a plastic BGA package, the glass transition temperature of 170‐215°C for bismaleimide triazine (BT) substrate puts an upper ceiling to the usable wire bond temperature. To compensate for the limitation in thermal energy, high frequency thermosonic bonding was proposed and successfully demonstrated for plastic BGA wire bonding. Design of experiment (DOE) and response surface methods (RSM) for process optimisation were used; bonded areas were also analysed using scanning electron microscope (SEM). Of the four major bonding parameters were investigated, ultrasonic power and bond force appeared to be the most important control factor for wire pulls and ball shear force optimisation. The results show that bonding at low temperature is viable with the use of high frequency transducer wire bonder.

To provide a design guideline for an automotive electronic module in order to improve its reliability in elevated environmental environments as well as in vibration environments.

Wire looping profiles, gel heights, and effects of mechanical vibration on aluminium wire bond failures are studied. Natural frequencies of various wire profiles are evaluated and effects of gel heights on reliability of products are studied using stochastic finite element analyses. The frequency dependent properties of silicone gels used in electronic modules are characterized by the corn and plate test. An experiment was also conducted in order to confirm numerical results.

The present study shows that the gel plays an important role in wire bond failures and reliability of the product. The gel reduces the amplitude of vibration of electronic modules due to its damping characteristics. However, both analytic and experimental results indicate that the gel imposes extra weight on the wires and may induce stresses on heels.

In the future study, it is suggested that other gel materials should be studied since the properties of gel strongly depend on the frequency which will affect the fatigue behavior of bonding wires.

The findings can be used as general design guidelines for wire bonding for automotive electronic modules.

The results will be very useful to design bonding wires for automotive electronic modules.