Semiconductor build-up package

The present invention is relating to a semiconductor package, more particularly to a semiconductor build-up package with expanded electrical function. A semiconductor build-up package includes a die, a circuit board and at least a dielectric layer. The circuit board has a surface for building up the dielectric layer, and the surface has a cavity for accommodating the die. The inside of multi-layer circuit board has conductive traces for expanding the electrical function of semiconductor build-up package. Each dielectric layer has conductive columns so that the die may electrically connect with the outermost dielectric layer. At least a conductive column is bonded on the surface of the multi-layer circuit board for inner electrical connection.