SEMICONDUCTOR PACKAGE

A semiconductor package includes a buffer die, semiconductor chip stacks stacked on the buffer die, each of the semiconductor chip stacks including a plurality of first semiconductor chips and a second semiconductor chip on the plurality of first semiconductor chips, and a mold layer covering an upper surface of the buffer die and side surfaces of the semiconductor chip stacks. Each of the first semiconductor chips and the second semiconductor chip includes a wiring part including multilayer wirings, an upper connection structure on the wiring part and having a plurality of upper conductive pads and a lower connection structure under the wiring part and having a plurality of lower conductive pads, and the second semiconductor chip further includes a redistribution layer on the upper connection structure and having an insulating layer and a plurality of redistribution pads in the insulating layer.