Ultrathin CuSiN/p-SiC:H bilayer capping barrier for Cu/ultralow-k dielectric integration

Abstract

Different amount of porosity, which leads to the change in the dielectric constant of films from 4.1 to 2.9, can be created in amorphous SiC:H (a-SiC:H) films. The resultant CuSiN/a-SiC:H bilayered structure, as a copper capping barrier, shows improved thermal stability properties, lower leakage current density, and a low effective dielectric constant (keff) for the integrated ultralow-k a-SiOC:H film. This integrated film structure has the potential to meet the need of the 45 nm and lower technology node. Detailed characterizations of the integrated films were conducted to illustrate the possible mechanisms in the improvement of the film properties.