Patent ID: 8558379

Claim:
A packaged microelectronic element, comprising: a microelectronic element having a front surface and a plurality of first solid metal posts extending away from the front surface, each first post having a width in a direction of the front surface and a height extending from the front surface, wherein the height is at least half of said width; and a substrate having a top surface and a plurality of second solid metal posts extending from the top surface and joined to the first solid metal posts with a fusible metal, said second posts having top surfaces and edge surfaces extending abruptly away from said top surfaces of said second posts, the substrate including terminals at a bottom surface opposite the top surface of said substrate, and conductive interconnects extending through the substrate and electrically connecting the terminals with the second solid metal posts, wherein said plurality of first solid metal posts are etched metal posts and said plurality of second solid metal posts are etched metal posts having a frustoconical shape.