A cavity-down type package for a semiconductor device comprises an insulating base substrate (6) on which the semiconductor device (1) is mounted, and another insulating cap substrate (8) with plural outer connection terminals (5) on its outer surface and with electrodes (11) provided on conductive layers (4) for electric conduction on its inner surface. The electrodes on the insulating base substrate and those (11) on the insulating cap substrate (8) are connected with each other by means of conductive material such as bumps.
