Abstract: The invention relates to a self-supporting composite element and to a method of producing same. The composite element comprises a substrate of electronic conductive material which is covered with metal nanowires that are essentially oriented along a plane that is perpendicular to the substrate. The element is produced in a cell comprising a cathode which is formed by the substrate to be covered, one or more anodes and an electrolyte which is formed by a solution of a precursor of the metal material and optionally containing a conductive ionic salt, a flat porous membrane which is placed between the cathode and each of the anodes and a spacer element between each membrane and the anode adjacent thereto, the different constituent parts of the cell being maintained in contact.

Abstract: A method of fabricating an electrically conductive mechanical interconnection element (12) comprises: a first stage of electrochemically depositing a structure comprising a plurality of metal wires (2a) of sub-micrometric diameter projecting from the likewise metallic surface of a substrate (2); and a second stage of controlled partial dissolution of said wires to reduce their diameter. A method of making a mechanical and/or electrical interconnection, the method comprising the steps consisting in: fabricating two interconnection elements by a method as described above; and placing said interconnection elements face to face and pressing one against the other so as to cause the nanometric wires projecting from the surfaces of said elements to interpenetrate and tangle together. A three-dimensional electronic device comprising a stack of microelectronic chips mechanically and electrically connected to one another by such interconnection elements.

Abstract: A method of fabricating an electrically conductive mechanical interconnection element (12) comprises: a first stage of electrochemically depositing a structure comprising a plurality of metal wires (2a) of sub-micrometric diameter projecting from the likewise metallic surface of a substrate (2); and a second stage of controlled partial dissolution of said wires to reduce their diameter. A method of making a mechanical and/or electrical interconnection, the method comprising the steps consisting in: fabricating two interconnection elements by a method as described above; and placing said interconnection elements face to face and pressing one against the other so as to cause the nanometric wires projecting from the surfaces of said elements to interpenetrate and tangle together. A three-dimensional electronic device comprising a stack of microelectronic chips mechanically and electrically connected to one another by such interconnection elements.

Abstract: The invention relates to a self-supporting composite element and to a method of producing same. The composite element comprises a substrate of electronic conductive material which is covered with metal nanowires that are essentially oriented along a plane that is perpendicular to the substrate. The element is produced in a cell comprising a cathode which is formed by the substrate to be covered, one or more anodes and an electrolyte which is formed by a solution of a precursor of the metal material and optionally containing a conductive ionic salt, a flat porous membrane which is placed between the cathode and each of the anodes and a spacer element between each membrane and the anode adjacent thereto, the different constituent parts of the cell being maintained in contact.