Method for fabricating metal gates in deep sub-micron devices

摘要

A method for fabricating metal gates in deep sub-micron CMOS devices. The method blanket deposits a transition metal nitride layer on top of a gate dielectric layer for forming gate electrodes for both a PMOS and an NMOS device. After a cap layer is deposited on top of the gate electrode for PMOS, a rapid thermal annealing process is carried out to drive out nitrogen from the transition metal nitride on top of the NMOS. Gate electrodes having different work functions on top of the PMOS and NMOS are thus achieved simultaneously by the same fabrication process.