A solid-state element device having: a solid-state element having a pad electrode smaller than a contact electrode, the solid-state element being flip-mounted; a power receiving/supplying portion for receiving/supplying a power, the power receiving/supplying portion being bonded to the solid-state element such that an element mounting surface thereof is nearly flush with a mounting surface of the solid-state element; and an inorganic sealing portion for sealing the solid-state element formed of an inorganic sealing material and a thermal expansion coefficient equal to that of the power receiving/supplying portion. The inorganic sealing portion defines an air layer between the solid-state element and the power receiving/supplying portion.