A method for fabricating a semiconductor package includes forming a release layer on a first carrier substrate. An etch stop layer is formed on the release layer. A first redistribution layer is formed on the etch stop layer and includes a plurality of first wires and a first insulation layer surrounding the plurality of first wires. A first semiconductor chip is formed on the first redistribution layer. A solder ball is formed between the first redistribution layer and the first semiconductor chip. A second carrier substrate is formed on the first semiconductor chip. The first carrier substrate, the release layer, and the etch stop layer are removed. The second carrier substrate is removed.