Abstract: A method and system for patterning a metal layer of a semiconductor device is disclosed. The method and system includes providing a material with an antireflective low dielectric constant hard mask layer (antireflective low k hard mask layer) on top of the metal layer, and providing a photoresist pattern on top of the anti-reflective low k hard mask layer. The method and system further includes etching of the anti-reflective low k hard mask layer and etching of the metal layer, wherein the photoresist is removed but the anti-reflective low k hard mask layer remains. In a preferred embodiment, the mask layer can also be applied at low temperatures (i.e., >300.degree.) to ensure that the physical properties of the integrated circuit are not affected. Finally, the low k material does not have to be removed after processing.

Abstract: An etching process for DUV photolithography is provided for etching a layer of anti-reflection coating (ARC) comprising spin-on organic ARC material which is formed beneath a layer of photoresist. After patterning the layer of photoresist, the layer of ARC is etched by employing a mixture of oxygen plasma, nitrogen plasma, and at least one inert gas. Anisotropic etching of the layer of ARC is provided with the process of the present invention. In comparison with prior art etching processes for etching a layer of ARC, the process of the present invention provides a favorable etch rate with improved selectivity over the etching of the layer of photoresist. The layer of ARC is etched without causing lateral erosion of the layer of photoresist. Faceting of the top edges of the corners of the layer of photoresist is also minimized. The profile of the layer of photoresist is essentially maintained thereby enabling for critical dimension fidelity.