US Patent 7994644 Package stacking through rotation

A packaged microelectronic element includes a package element that further includes a dielectric element having a bottom face and a top face, first and second bond windows extending between the top and bottom faces, a plurality of chip contacts disposed at the top face adjacent to the first and second bond windows, and first and second sets of package contacts exposed at diagonally opposite corner regions of the top face, wherein the first and second sets conductively connected to the chip contacts. There is also a microelectronic element adjacent to the bottom face of the dielectric element, as well as bond wires extending through the first and second bond windows to conductively connect the microelectronic element to the chip contacts.