Abstract: A structure to enable damascene copper semiconductor fabrication is disclosed. There is a silicon nitride film for providing a diffusion barrier for Cu as well as an etch stop for the duel damascene process. Directly above the silicon nitride film is a silicon oxynitride film. The silicon oxynitride film is graded, to form a gradual change in composition of nitrogen and oxygen within the film. Directly above the silicon oxynitride film is silicon oxide. The silicon oxide serves as an insulator for metal lines. Preferably, the film stack of silicon nitride, silicon oxynitride and silicon oxide is all formed in sequence, within the same plasma-processing chamber, by modifying the composition of film-forming gases for forming each film.

Abstract: A clean-enclosure to protect a reticle from contamination when using extreme ultraviolet (EUV) lithography is disclosed. The clean-enclosure consists of frame and a cover attached to the frame. The cover contains an exposure window comprised of a thin film of silicon. This thin film window allows EUV light to pass through to the reticle and reflect onto the photoresist layer of a semiconductor substrate with minimal transmission loss. Also, a process for forming the silicon thin film exposure window is disclosed.