Some embodiments include an apparatus having a first chip and a second chip. Each of the first and second chips comprises a multilevel wiring structure and a redistribution wiring layer over the multilevel wiring structure. The redistribution wiring layers include redistribution wiring and pads electrically coupled to the redistribution wiring. The first chip is mounted above the second chip so that the redistribution wiring layer of the first chip faces the redistribution wiring layer of the second chip. The pad of the first chip faces the pad of the second chip, and is vertically spaced from the pad of the second chip by an intervening insulative region. The redistribution wiring of the second chip is electrically coupled to the redistribution wiring of the first chip through a bonding region.