Novellus Systems Incorporated

Atul Gupta

Thomas W Mountsier

Yongsik Yu

William Crew

Michael Carris

Karen Billington

Bart Jan Van Schravendijk

Jengyi Yu

Haiying Fu

Somnath S Nag

Ka Shun Wong

Sanjeev Jain

The present invention provides a low dielectric constant copper diffusion barrier film composed, at least in part, of boron-doped silicon carbide suitable for use in a semiconductor device and methods for fabricating such a film. The copper diffusion barrier maintains a stable dielectric constant of less than 4.5 in the presence of atmospheric moisture.

Low-k b-doped SiC copper diffusion barrier films

Copper diffusion barrier films having a boron-doped silicon carbide layer with at least 25% boron by atomic weight of the layer composition have advantages for semiconductor device integration schemes. The films have an integration worthy etch selectivity to carbon doped oxide of at least 10 to 1, can adhere to copper with an adhesion energy of at least 20 J/m, and can maintain an effective dielectric constant of less than 4.5 in the presence of atmospheric moisture. The films are suitable for use in a wide range of VLSI and ULSI structures and devices.

Boron-doped SIC copper diffusion barrier films

Low-k B-doped SiC copper diffusion barrier films

Two sequential treatments within a chemical vapor deposition chamber, or within sequential chambers without a vacuum break, are performed on a copper layer to clean and passivate the copper surface prior to deposition of a copper diffusion barrier layer or a dielectric layer. The first treatment includes an ammonia, a hydrogen, or a hydrocarbon plasma cleaning of the copper surface followed by a short initiation of an organosilane precursor or a thin silicon nitride layer. A copper diffusion barrier layer may then be formed over the pretreated copper surface using an organosilane plasma, with or without a carbon dioxide or a carbon monoxide, or a silane with a nitrogen gas and an ammonia gas. Copper diffusion is retarded and film adhesion is improved for a dielectric layer or a copper diffusion barrier layer on the copper surface.

Systems and methods to retard copper diffusion and improve film adhesion for a dielectric barrier on copper

Growing community of inventors

Santa Clara, CA, United States of America

Atul Gupta