Anisotropic and non-filled adhesives were investigated for contacting two large rigid partners, i.e. SMT components on PCB's. To this end, appropriate semi automated fabrication processes were developed. The component used was a QFP160 (28 mm)~2, the types of PCB's included epoxide reinforced with glass fibres (FR4) or with aramide fibres, metallisations contained SnPb, Pd, Cu, and some 20 adhesives were tested. Both adhesive technologies were investigated regarding the manufacturing quality of the contacts as well as their reliability. The investigations included technological measurements and analytical characterisations, which were carried out before, while or after various ageing schemes. Most important, the contact resistance was monitored for some 90.000 contacts and shear forces were measured for individual pins. Analytical investigations included: cure of the adhesives, morphology of the contacts, conduction mechanisms, and failure mechanisms. With both adhesive technologies, a good manufacturing quality can be obtained using the optimized processes. The reliability of the contacts is excellent after temperature cycles, shock freezing of soaked humid joints, and prolongued humidity.
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