The adhesion properties of poly(arylene ether) (PAE-2), a thermoplastic, based isotropic conductive adhesive (ICA) materials were investigated. PAE-2-based ICAs, as well as epoxy-based ICAs (thermosets), showed a dramatic reduction in adhesion to a NiAu surface during the 85 ± C/85% RH aging test. Self-assembled monolayer (SAM) molecules were introduced to the interface between the PAE-2-based ICA and the metal bond pad to increase the adhesion strength during the aging test. By depositing SAMs on the NiAu surface, the adhesion strength after aging was signi cantly improved. Finally, the SAM treatment on NiAu surface did not adversely affect the contact resistance stability.

Dynamic shock compaction offers the potential of fabricating bulk nanocrystalline functional materials via consolidation of amorphous or nanocrystalline alloy powders, while retaining the metastable structure and/or nanograin size of starting powders. In this work, gas-gun impact, double-tube explosion and underwater explosion techniques were utilized to consolidate exchange-coupled R 2 Fe 14 B/α-Fe (R=Nd, Pr) hard/soft phase nanocomposite powders. Design of the consolidation fixtures, densification conditions, and starting powder properties allowed control of the final density and the nanoscale structure of the hard/soft magnetic phases in the recovered shock-compacted samples. Highly dense compacts (~99% of full density) were obtained under optimized shock consolidation conditions. Transmission electron microscopy observations revealed complete retention of the nanostructure, which was within 15-25 nm in the final shock-compacted composite magnets. Retention of the nano-scale structure in the shock consolidated compacts ensured exchange coupling between the hard and soft phases, resulting in optimal magnetic properties. In this paper, the unique attributes of the shock-densification process in forming and retaining the nanocrystalline structure, and therefore leading to improved magnetic properties will be described.

The adhesion and electrical properties of a PAE-2-based isotropically conductive adhesive (ICA) material were investigated. PAE-2 (thermoplastic polymer)-based ICAs, as well as a commercial epoxy-based ICA, showed dramatic reduction in adhesion to a NiAu surface after the 85 ± C/ 85% RH aging test, while the adhesion to a SnPb surface did not change much. To improve the adhesion strength of PAE-2 to a Ni:Au surface after the humidity aging test, coupling agents and epoxy blends were used. The formulation with a higher amount of epoxy showed a higher adhesion strength. The combined use of epoxy blending and coupling agents was effective in increasing the adhesion strength of PAE-2 before aging and also in maintaining adhesion at a 50% level after humidity aging. However, its adhesion strength to NiAu was reduced to less than 50% after 85 ± C/ 85% RH aging. PAE-2-based ICAs showed excellent reworkability.

The adhesion properties of poly (arylene ether) (PAE2 , thermoplastic) based isotropic conductive adhesive (ICA) material were investigated. PAEZ based ICAs as well as epoxy-based ICAs (thermoset) showed a dramatic reduction in adhesion onto a NiAu surface during 85 "C/85% RH aging tests. It was found that a NiAu surface is more hydrophilic than a SnPb surface, which allows easier introduction into the interface between polymer and metal pads, as such hydrogen bonds between polymer and metal pads could be disrupted. To improve the adhesion strength of the PAE2 on a Ni/Au surface during aging tests, coupling agents and epoxy blends have been incorporated into the PAEZ formulations. Additionally, a self-assembled mono-layer ( S A M ) molecule isintroduced to the interface between the polymer and the metal bond pad to increase the adhesion of PAEZ based ICA during aging. The combined usage of epoxy blending and coupling agents is considerably effective at increasing the adhesion strength of PAEZ before aging. With these additives, 50% of the adhesion strength is maintained after 85 "C/85% RH aging.By depositing a self-assembled monolayer molecule on the top of the NiAu substrate, the adhesion strength after aging of epoxy blending/couplmg agent incorporated PAEZ as well as the pure PAE2 after aging is significantly improved.

Dynamic consolidation of powders was studied to fabricate exchange-coupled Pr 2 Fe 14 B/-Fe nanocomposite bulk magnets, using explosively generated shock waves transmitted through water. The planar shock wave propagating into the powder had a peak pressure calculated to be 12 GPa. Extensive plastic deformation of the powders and solid-state interfacial bonding of the ribbon flakes was obtained during shock compaction, resulting in fabrication of bulk compacts with nearly full density. Retention of nano-scale structure, and in fact further refinement of the grain size, ensured exchange coupling between the hard and soft phases, resulting in magnetic properties better than those of resin-bonded commercially available magnets. Post-shock annealing of the compacts at 750 and 850 C resulted in deterioration of the magnetic properties due to slight grain growth and decoupling of exchange interactions between hard and soft phases. The results illustrate that dynamic shock consolidation employing explosive loading is a viable method for fabricating bulk nanocomposite magnets and the rapid thermal excursions can be controlled to minimize and in fact eliminate the detrimental effects otherwise observed during high temperature sintering and annealing of the powders.