Electrical and Reliability Perspectives for Self-Forming Barrier CuSc Metallization

The electrical and reliability characteristics of CuSc layer on SiO2 film are reported. In an integrated CuSc/SiO2 structure, a self-forming barrier (SFB) was formed at the interface by thermal annealing at 425 °C. After annealing, electrical characteristics, electromigration, and time-dependent-dielectric-breakdown reliability were improved due to the formation of SFB. This shows that CuSc has great potential as a liner- and barrier-free interconnect material.