Insulating adhesive tape, and lead frame and semiconductor device employing the tape

A lead frame having inner leads fixed with an insulating adhesive tape, comprising a base supporting film and and an adhesive layer formed on at least one surface thereof, said adhesive layer being formed of a thermoplastic polymer comprising a thermoplastic polyimide, said thermoplastic polymer having a glass transition temperature ranging from 180.degree. C. to 280.degree. C. and an elastic modulus ranging from 10.sup.10 dyne/cm.sup.2 to 10.sup.11 dyne/cm.sup.2 at 25.degree. C., said modulus including a value ranging from 10.sup.2 dyne/cm.sup.2 to 10.sup.9 dyne/cm.sup.2 at a temperature between 250.degree. C. and 300.degree. C.

A semiconductor device wherein the inner leads of a lead frame is fixed with an insulating adhesive tape, said insulating adhesive tape having, on at least one surface of a base supporting film, an adhesive layer formed of a thermoplastic polymer comprising a thermoplastic polyimide, said thermoplastic polymer having a glass transition temperature ranging from 180.degree. C. to 280.degree. C. and an elastic modulus ranging from 10.sup.10 dyne/cm.sup.2 to 10.sup.11 dyne/cm.sup.2 at 25.degree. C., said modulus ranging from 10.sup.2 dyne/cm.sup.2 to 10.sup.9 dyne/cm.sup.2 at least one temperature between 250.degree. C. and 300.degree. C., at least the portion of said inner leads fixed with said insulating adhesive tape being encapsulated with a resin.