Patent ID: 7759244

Claim:
A method for fabricating a dual damascene structure, comprising: providing a substrate, the substrate comprising a dielectric layer, wherein the dielectric layer comprises an etching stop layer therein, and the etching stop layer has at least an opening defining a via hole pattern; performing a first etching process on the dielectric layer until exposing the etching stop layer so as to form at least a first opening in the dielectric layer, the first etching process also forming a polymer in the first opening, wherein the first opening in the dielectric layer is an inductor trench overlapping the opening of the etching stop layer, and wherein the first etching process does not etch through the etching stop layer; performing at least a polymer-removing step, wherein the polymer-removing step comprises using hydro-fluorocarbon to remove the polymer; performing a second etching process on the dielectric layer after the polymer-removing step so as to form a second opening within the first opening and to expose a barrier layer that is positioned at a bottom of the second opening, and the second opening being positioned at a bottom of the first opening, wherein the second opening in the dielectric layer is a via hole; performing a third etching process after the second etching process to remove the exposed barrier layer at the bottom of the second opening; and filling the first opening and the second opening with a conductive material so as to form the dual damascene structure, wherein the dual damascene structure forms an inductor structure.