A method for fabricating a core layer of a substrate, comprising: placing a first die with a die pad on top of a peelable tape covering a base while the die pad is in contact with the tape; then, encapsulating the first die and the die pad using a molding compound; removing the base and the peelable type after the encapsulating step; forming a first dielectric layer on one surface of the molding compound and a second dielectric layer on another surface of the molding compound after removing the base and the peelable type; placing a first conductive layer on top of the first dielectric layer and a second conductive layer on top of the second dielectric layer; forming a through hole through the first conductive layer, the second conductive layer, the first dielectric layer, the second dielectric layer, and the molding compound after placing the first and second conductive layers; forming a laser via through the first conductive layer and the first dielectric layer connected to the die pad of the first die after placing the first and second conductive layers; plating the through hole and laser via with a metal plate, wherein an outer surface of the metal plate, an outer surface of the first conductive layer, and an outer surface of the laser via form a flat surface; attaching a first photo resist film covering the metal plate, the laser via, and the first conductive layer; attaching a second photo resist film covering the metal plate and the second conductive layer; etching the first conductive layer on areas not protected by the first resist film; etching the second conductive layer on areas not protected by the second resist film; and removing the first resist film and the second resist film. placing a first die with a die pad on top of a peelable tape covering a base while the die pad is in contact with the tape; then, encapsulating the first die and the die pad using a molding compound; removing the base and the peelable type after the encapsulating step; forming a first dielectric layer on one surface of the molding compound and a second dielectric layer on another surface of the molding compound after removing the base and the peelable type; placing a first conductive layer on top of the first dielectric layer and a second conductive layer on top of the second dielectric layer; forming a through hole through the first conductive layer, the second conductive layer, the first dielectric layer, the second dielectric layer, and the molding compound after placing the first and second conductive layers; forming a laser via through the first conductive layer and the first dielectric layer connected to the die pad of the first die after placing the first and second conductive layers; plating the through hole and laser via with a metal plate, wherein an outer surface of the metal plate, an outer surface of the first conductive layer, and an outer surface of the laser via form a flat surface; attaching a first photo resist film covering the metal plate, the laser via, and the first conductive layer; attaching a second photo resist film covering the metal plate and the second conductive layer; etching the first conductive layer on areas not protected by the first resist film; etching the second conductive layer on areas not protected by the second resist film; and removing the first resist film and the second resist film.