Low-cost semiconductor device package and process

Claim 1

An hermetically sealed semiconductor device package, which comprises: a ceramic substrate, a semiconductor die, a body of cured polyimide resinous material cured from a composition containing a crosslinkable resinous polyimide precursor which will cure to give a polyimide having a recurring unit of the formula: ##STR2## in which R 1 and R 2 are radicals of a tetravalent aromatic group and a divalent aromatic group, respectively, and n is a positive integer, a sufficient amount of an alkylaminotrialkoxysilane crosslinking agent to cure said resinous polyimide precursor, a sufficient amount of a finely divided conductive metal to render said composition conductive in the cured state and a polar organic solvent for said polyimide precursor and alkylaminotrialkoxysilane crosslinking agent, said body of cured polyimide resinous material containing the finely divided conductive metal, said body attaching said semiconductor die to said ceramic substrate, and a closure covering said semiconductor die and said body of cured polyimide resinous material, said closure being in sealed relationship with said ceramic substrate, so that said closure, body of cured resinous material and ceramic substrate provide hermetic isolation for said semiconductor die.