A semiconductor power module includes a semiconductor chip thermally interfaced to a ceramic substrate and a leadframe defined by a flexible circuit disposed intermediate the chip and the ceramic substrate. The flexible circuit includes a conductor layer that is selectively encased in an insulated jacket to ensure adequate electrical insulation between the conductor layer and adjacent conductive surfaces. Preferably, the module is constructed for double side cooling by sandwiching the chip between a pair of ceramic substrates and providing intermediate flexible circuit leadframes on both sides of the chip for electrically accessing the chip terminals.