A bi-planar multi-chip package has die mounted on both sides of an insulating flexible carrier. The die are located in two parallel planes, with the flexible carrier located on a third plane between the two die planes. The die are mounted with the active circuit area facing each other on opposing sides...http://www.google.com/patents/US5477082?utm_source=gb-gplus-sharePatent US5477082 - Bi-planar multi-chip module
