Method for forming a dual damascene wiring pattern in a semiconductor device

Abstract

In a method for forming a dual damascene wiring pattern, an etch stop film and an interlayer dielectric film comprising an SiOC:H group material are formed on a substrate having an electrical connection layer formed thereon. An anti-reflection layer is formed on the interlayer dielectric film. A primary opening is formed by etching the anti-reflection layer and the interlayer dielectric film to expose a surface of the etch stop film. A sacrificial film is formed comprising a low dielectric constant material in the primary opening and on the anti-reflection layer. A trench photoresist pattern having a width larger than that of the primary opening is formed on the sacrificial film after plasma-processing the sacrificial film. The sacrificial film, the anti-reflection layer and the interlayer dielectric film are sequentially etched using the trench photoresist pattern as an etch mask so as to form a secondary opening of a trench shape, and the trench photoresist pattern is removed, said secondary opening extending from an upper portion of the primary opening. The sacrificial film remaining is removed, the exposed etch stop film and anti-reflection layer are removed, the primary and secondary openings are filled with metal so as to be electrically coupled with the electrical connection layer. In this manner, damage to the etch stop layer is mitigated or eliminated during processing.