an integrated electronic device having an electric connection between a first electrode of a semiconductor chip and a second electrode of a circuit board . one embodiment according to the present invention is a method for fabricating an integrated electronic device having an electric connection between a first electrode of a semiconductor chip and a second electrode of a circuit board , both surfaces of the first and second electrodes having an adhesive tendency to molten metal , the method comprising the steps of forming a metal bump on the first electrode , the metal bump being made of a soldering metal alloy consisting of a solid phase component and a liquid phase component at an operating temperature ; and forming an electric connection between the first electrode and the second electrode by heating the soldering metal alloy so as to adhere to the surface of the second electrode .