Surface-mount attachment reliability of clip-leaded ceramic chip carriers on FR-4 circuit boards

Thermal Fatigue Behavior of Sn-Rich (Pb-Free) Solders

“…Extensive work has been done on characterizing the life of solder-joint specimens by testing entire electronic packages. [2][3][4][5][6][7][8] This approach enables the determination of the overall reliability of the component, from the macroscopic mechanical response of the solder joints.…”

Application of Al2O3-based polyimide composite thick films to integrated substrates using aerosol deposition method

“…Finally, compositions of materials in polymer composites have to be uniform in the submicrometer range. The non-uniform composition of substrate materials over micrometer range can bring out electromagnetic problems in integrated circuits [17,18].…”

Surface Mount Solder Joint Long‐term Reliability: Design, Testing, Prediction

“…The solution of choice is the attachment of the ceramic chip carrier to the substrate utilising edge clip-leads, but even highly compliant lead designs are inadequate for large expansion mismatches and long cyclic lives. 4,11 In addition, highly compliant leads can present manufacturability problems due to easy accidental bending of the leads and functional problems due to high electrical losses at high signal speeds from the long lead length.…”

“…5 Using constraining layers, e.g., copper-clad Invar, copper-clad molybdenum, graphite fibres, Kevlar fibres, etc., the CTE for FR-4 epoxy/glass substrates which can range from 16 to 24 ppm/°C, depending primarily on resin content, has been reduced to as low as 8·6 ppm/°C by substituting copper-clad Invar layers for the copper power and ground layers 3,5 and 6 ppm/°C by substituting Kevlar for the glass fibre reinforcements. 7 Conversely, plastic leaded components not only have a CTE range (20-23 ppm/°C) falling within the CTE range of FR-4 substrates, and thus like ceramic-on-ceramic are inherently CTE tailored to a large extent, but also have leads that provide varying degrees (dependent on design and material) of compliancy [7][8][9][10][11][12][13] to accommodate expansion mismatch. Solution 2: Attachment Compliancy to Accommodate Expansion Mismatch Attachment compliancy 7,11-13 comes primarily from suitably designed component leads and to a much smaller degree can be assisted by compliant surface pad layers on the substrate.…”