| abstract |
A packaging substrate ( 310 ) includes a semiconductor interposer ( 120 ) and at least one other intermediate substrate ( 110 ), e.g. a BT substrate. The semiconductor interposer has first contact pads ( 136 C) attachable to dies ( 124 ) above the interposer, and second contact pads ( 340 ) attachable to circuitry below the interposer. Through vias ( 330 ) are made in the semiconductor substrate ( 140 ) of the interposer ( 120 ). Conductive paths going through the through vias connect the first contact pads ( 136 C) to the second contact pads ( 340 ). The second contact pads ( 340 ) protrude on the bottom surface of the interposer. These protruding contact pads ( 340 ) are inserted into vias ( 920 ) formed in the top surface of the BT substrate. The vias provide a strong mechanical connection and facilitate the interposer handling, especially if the interposer is thin. In some embodiments, an interposer or a die ( 124.1 ) has vias in the top surface. Protruding contact pads ( 340.1, 340.2 ) of another die ( 124.1, 124.2 ) are inserted into these vias to provide a strong connection. |