3d semiconductor device with interposer and method therefor

A semiconductor device comprising:

• an interposer including:
• a first set of conductive connection pads at a first major side of an interposer substrate,
• a second set of conductive connection pads at a second major side of the interposer substrate, the second major side opposite of the first major side, and
• a plurality of sidewall pads exposed along an outer perimeter of the interposer substrate;
• a first semiconductor die mounted on the first major side of the interposer substrate, first bond pads of the first semiconductor die conductively connected to the first set of conductive connection pads;
• and
• a second semiconductor die mounted on the second major side of the interposer substrate, second bond pads of the second semiconductor die conductively connected to the second set of conductive connection pads.

A method comprising:

• forming an interposer including a first set of conductive connection pads exposed at a first major side of an interposer substrate and a second set of conductive connection pads exposed at a second major side of the interposer substrate, the second major side opposite of the first major side;
• mounting an active side of a first semiconductor wafer on the first major side of the interposer substrate;
• mounting an active side of a second semiconductor wafer on the second major side of the interposer substrate, a sandwich-like structure formed by a stacked die arrangement of the first semiconductor wafer, interposer, and second semiconductor wafer;
• and
• singulating the sandwich-like structure to form a plurality of individual semiconductor device units, a plurality of sidewall connection pads exposed along an outer perimeter of the interposer.