Abstract: A polymer is prepared from monomers containing at least one carbon to carbon double bond and at least one siloxane moiety and from monomers containing at least one carbon to carbon double bond and at least one moiety that imparts reactivity to the resulting polymer. Siloxane moieties impart permeability; reactivity is obtained from monomers containing epoxy, oxetane, oxazoline, benzoxazine, or episulfide functionality. Additional properties can be added to the polymer by the inclusion in the initial polymerization mix of monomers that impart low glass transition temperature, high glass transition temperature, and adhesion. The level of each functionality can be controlled by the practitioner by varying the amount of monomer containing that functionality added to the initial polymerization. These materials can be B-staged.

Abstract: A semiconductor assembly comprising a semiconductor chip on a substrate is adhered to the substrate using a dual cure B-stageable adhesive comprising two chemical compositions, (i) a first composition comprising a curable monomeric or polymeric compound or resin and a curing initiator or curing agent for that compound or resin, and (ii) a second composition comprising a monomeric or polymeric compound or resin and a curing initiator or curing agent for that compound or resin, in which the curing temperatures or curing temperature ranges are sufficiently separated to allow the composition with the lower curing temperature, the first composition, to cure without curing the composition with the higher curing temperature, the second composition.