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AssigneeInternational Business Machines Corporation
InventorsVladimir Jakubek, Heike Appelt, David John Russell, Cory J. Ruud
Estimating the term…
Photoimagable polymers, as well as dielectric materials and their manufacture and use in the production of printed circuit boards and printed wiring boards are described. The polymers comprise between about 30 and about 70 parts of a polyfunctional resin and between about 70 and about 30 parts of the condensation product of an epihalohydrin and a bisphenol based on 100 parts by weight of resin. The polymer is cured by a photocationic initiator. It is characterized by a glass transition temperature of at least about 140° C. and a flex fatigue life of at least about 10,000 cycles at a 3% strain. Optionally, less than 10 parts of a third specified epoxy resin may be added to the mixture to improve flexibility without decreasing the glass transition temperature of the polymer.
A photoimaged polymeric composition that has been at least partially cured by a photocationic initiator, said polymeric composition comprising a fully cured resin mixture of a polyfunctional epoxy resin and the condensation product of a bisphenol and an epihalohydrin, said polymeric composition having a glass transition temperature of at least about 140° C. and a flex fatigue life at room temperature of at least about 10,000 cycles normalized to a 3% strain.
A photoimaged and fully cured dielectric polymeric film having a flex fatigue life of at least about 10,000 cycles at about a 3% strain, and a glass transition temperature of at least about 140° C.
A build-up circuit package comprising a polymer prepared from a mixture of
A photoimaged dielectric polymer having a flex fatigue resistance of at least about 10,000 cycles normalized to a 3% strain as determined on a 1″ strip of the polymer having a width of ⅛″ said strip subject to testing when formed around a mandrel, and a glass transition temperature of at least about 140° C., the polymer comprising, based on 100 parts by weight of the reaction product, between about 30 parts and about 70 parts by weight of a polyfunctional epoxy resin comprising the triglycidyl ether of tris (hydroxy phenyl)methane and between about 70 parts and about 30 parts by weight of the condensation product of diglycidyl ether of a bisphenol A, said polymer optionally including up to 10 parts of a third epoxy resin capable of improving the flex fatigue life of the polymer without lowering the glass transition temperature below about 140° C., wherein the third epoxy resin is selected from the group consisting of an epoxidized phenolformaldehyde novolac having a weight per epoxide between about 172 and about 179 and a diglycidyl ether of bisphenol A having a weight per epoxide between about 600 and about 950, said reaction product cured with an effective amount of triphenyl sulfonium as a cationic photoinitiator and by heat.
Dependencies are inferred from the claim text.