Buildup board structure

A buildup board structure, comprising at least one third buildup unit, the third buildup unit comprising at least one third buildup body,

• wherein the third buildup body is provided with a central hole and comprises a third upper flexible board, a third intermediate flexible board, a third middle flexible board, a third lower flexible board, a plurality of magnetic induction coils, a first dielectric layer, a second dielectric layer and a plurality of connection pads, the third upper flexible board, the first dielectric layer, the third intermediate flexible board, the third middle flexible board, the second dielectric layer and the third lower flexible board are sequentially stacked from top to bottom, the magnetic induction coils are embedded in the third upper flexible board, the third intermediate flexible board, the third middle flexible board or the third lower flexible board, each magnetic induction coil embedded in the third upper flexible board is exposed to an upper surface of the third upper flexible board, each magnetic induction coil embedded in the third intermediate flexible board is exposed to a lower surface of the third intermediate flexible board, each magnetic induction coil embedded in the third middle flexible board is exposed to an upper surface of the third middle flexible board, each magnetic induction coil embedded in the third lower flexible board is exposed to a lower surface of the third lower flexible board, the magnetic induction coils in the third intermediate flexible board are not in contact with the magnetic induction coils in the third middle flexible board, the magnetic induction coils in the third upper flexible board are electrically connected to the magnetic induction coils in the third intermediate flexible board via the corresponding connection pads penetrating through the first dielectric layer, the magnetic induction coils in the third upper and middle flexible boards are electrically connected via corresponding connection pads penetrating the first dielectric layer and the third intermediate flexible board, the magnetic induction coils in the third middle flexible board are electrically connected to the magnetic induction coils in the third lower flexible board via the corresponding connection pads penetrating the second dielectric layer, and each of the magnetic induction coils embedded in the third upper, intermediate, middle and lower flexible boards has a spiral shape and is configured in a horizontal plane.