A semiconductor structure includes an insulating layer, a plurality of stepped conductive vias and a patterned circuit layer. The insulating layer includes a top surface and a bottom surface opposite to the top surface. The stepped conductive vias are disposed at the insulating layer to electrically connect the top surface and the bottom surface. Each of the stepped conductive vias includes a head portion and a neck portion connected to the head portion. The head portion is disposed on the top surface, and an upper surface of the head portion is coplanar with the top surface. A minimum diameter of the head portion is greater than a maximum diameter of the neck portion. The patterned circuit layer is disposed on the top surface and electrically connected to the stepped conductive vias.