Patent ID: 8322032

Claim:
A method for manufacturing a substrate structure, comprising: providing a substrate, wherein the substrate has a patterned first metal layer, a patterned second metal layer and a through hole; forming a first dielectric layer and a second dielectric layer at a first surface and a second surface of the substrate respectively, wherein the second surface is opposite to the first surface; patterning the first dielectric layer and the second dielectric layer; forming a first trace layer at a surface of the patterned first dielectric layer, wherein the first trace layer is embedded into the patterned first dielectric layer and is coplanar with the first dielectric layer, comprising: forming a third metal layer at the surface of the patterned first dielectric layer; and reducing the thickness of the third metal layer, so that the remained third metal layer is embedded into the patterned first dielectric layer to form the first trace layer; and forming a second trace layer on a surface of the second dielectric layer, comprising: forming a fourth metal layer on the surface of the patterned second dielectric layer; reducing the thickness of the fourth metal layer, wherein the step of reducing the thickness of the fourth metal layer and the step of reducing the thickness of the third metal layer are in an etching step; and patterning the fourth metal layer so as to form the second trace layer, wherein the thickness of the formed fourth metal layer is larger than the thickness of the formed third metal layer, and the thickness of the reduced third metal layer is substantially equal to the thickness of the reduced fourth metal layer.