US Patent 10460971 Multi-chip package assembly

Methods of bonding chips to a substrate and transfer wafers used for such bonding include bonding chips to a first support wafer by a first adhesive layer. The chips are bonded to a second support wafer by a second adhesive layer. Regions of the first adhesive layer are selectively weakened to decrease an adhesive strength in weakened regions. The weakened regions correspond to a subset of chips. The second support wafer is separated from the first wafer, such that the subset of chips in the weakened regions debond from the first support wafer. The subset of chips are bonded to a target substrate.