US Patent 7420275 Boron-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/m2, 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.