Robust multi-layer wiring elements and assemblies with embedded microelectronic elements

An interconnect element 130 can include a dielectric layer 116 having a top face 116b and a bottom face 116a remote from the top face, a first metal layer defining a plane extending along the bottom face and a second metal layer extending along the top face. One of the first or second metal layers, or both, can include a plurality of conductive traces 132, 134. A plurality of conductive protrusions 112 can extend upwardly from the plane defined by the first metal layer 102 through the dielectric layer 116. The conductive protrusions 112 can have top surfaces 126 at a first height 115 above the first metal layer 132 which may be more than 50% of a height of the dielectric layer. A plurality of conductive vias 128 can extend from the top surfaces 126 of the protrusions 112 to connect the protrusions 112 with the second metal layer.