Plasma process-induced wire-to-wire leakage current for low-k SiOC/Cu damascene structure

The wire-to-wire leakage characteristics were evaluated for SiOC/Cu damascene structure. Our investigation focused on the influence of a trench formation process and the pre-treatment at cap-film deposition which are the main plasma processes in BEOL integration using low-k SiOC films. It became clear that the leakage current is sensitive to ashing conditions at a trench formation step and to cap-film deposition pre-treatment conditions. An optimized plasma process was proposed for Cu/SiOC integration.