A method of manufacturing a semiconductor package includes preparing a wafer structure having a first semiconductor substrate and a plurality of first front surface connection pads. A lower semiconductor chip having a preliminary semiconductor substrate and a plurality of second front surface connection pads are attached to the wafer structure such that the plurality of first front surface connection pads and the plurality of second front surface connection pads correspond to each other. A plurality of bonding pads is formed by bonding together the plurality of first front surface connection pads and the plurality of second front surface connection pads corresponding to each other. A second semiconductor substrate having a horizontal width that is less than that of the second wiring structure is formed by removing a portion of the preliminary semiconductor substrate.