An interposer to form a frame around a bottom chip bonded to a package substrate and to standoff a top chip or package for clearance of the bottom chip. The interposer has pins arrayed on a first side which are soldered to the package substrate for reduced interposer z-height and pads arrayed on a second side to which the top package (chip) is bonded. During assembly, the interposer pins may be pressed against pre-soldered pads and the solder reflowed to join the interposer to the package substrate. A top package (chip) is then joined to an opposite side of the interposer to integrate the first and second chips.