A substrate includes a first dielectric structure, a first circuit layer, a second dielectric structure and a second circuit layer. The first circuit layer is embedded in the first dielectric structure, and does not protrude from a first surface of the first dielectric structure. The second dielectric structure is disposed on the first surface of the first dielectric structure. The second circuit layer is embedded in the second dielectric structure, and is electrically connected to the first circuit layer. A first surface of the second circuit layer is substantially coplanar with a first surface of the second dielectric structure, and a surface roughness value of a first surface of the first circuit layer is different from a surface roughness value of the first surface of the second circuit layer.