Manufacturing method for wiring circuit substrate

A method of making a microelectronic element includes making a connection component by providing a metal layer having a top surface and a bottom surface, providing a dielectric layer over the top surface of the metal layer and forming openings in the dielectric layer to expose portions of the top surface of the metal layer. The method includes providing conductive elements atop the dielectric layer, at least some of the conductive elements extending through the openings in the dielectric layer and being in contact with the metal layer, and plating first conductive protrusions atop the at least some of the conductive elements extending through the openings in the dielectric layer, the first conductive protrusions extending away from the metal layer. The method includes selectively removing portions of the metal layer from the bottom surface of the metal layer to form second conductive protrusions that extend away from the first conductive protrusions. At least some of the first and second conductive protrusions are electrically interconnected with one another.