Abstract
A novel back end-of-line (BEOL) process scheme is proposed to improve negative bias temperature instability (NBTI) characteristics through the characterization of the impact of each BEOL process on NBTI of p+ gate metal oxide semiconductor field-effect transistor (PMOSFETs). It is demonstrated that NBTI is strongly dependent on the plasma enhanced nitride (PE-SiN) passivation film and H2 sintering anneal. A new process scheme of N2 annealing instead of H2 annealing prior to PE-SiN deposition is proposed and proven to be highly efficient in improving NBTI without degradation of device performance and n+ gate metal oxide semiconductor (NMOS) hot carrier lifetime.