1. A solid-state imaging apparatus comprising: a first package having a multilayered wiring structure and a step; a solid-state imaging device mounted on an outer surface side of the first package; one or a plurality of bare ICs disposed on an inner surface side of the first package and serving as a peripheral circuit or circuits of the solid-state imaging device; a second package having a multilayered wiring structure electrically connected to the multilayer wiring structure of the first package via a through hole in the step of the first package; and another one or a plurality of bare ICs disposed on one or both surfaces of the second package, wherein, the step is a region raised above the inner surface side of the first package, the one or plurality of bare ICs is electrically connected to the solid-state imaging device via the multilayer wiring structures of the first and second packages.