Tungsten carbides as a diffusion barrier for Cu metallization

Carbides of refractory metals have been used as diffusion barriers due to their high melting point and good thermal and mechanical stability. In this work binary WC films have been investigated as Cu diffusion barriers by using ex-situ sheet resistance (Rs), X-ray diffraction (XRD) measurement and in-situ laser light scattering measurements. It was found that the WC film has stronger oxidation resistance and a comparable diffusion barrier performance as W films. However, the Cu agglomeration was severe for the Cu/WC/Si structures