A semiconductor device includes a dielectric interposer, a first redistribution layer, a second redistribution layer and conductive structures. The conductive structures are through the dielectric interposer, wherein the conductive structures are electrically connected to the first redistribution layer and the second redistribution layer. Each of the conductive structures has a tapered profile. A width of each of the conductive structures proximal to the first redistribution layer is narrower than a width of each of the conductive structure proximal to the second redistribution layer.