METHOD FOR FORMING DUAL HIGH-K METAL GATE USING PHOTORESIST MASK AND STRUCTURES THEREOF

摘要

Methods for forming a front-end-of-the-line (FEOL) dual high-k gate using a photoresist mask and structures thereof are disclosed. One embodiment of the disclosed method includes depositing a high-k dielectric film on a substrate of a FEOL CMOS structure followed by depositing a photoresist thereon; patterning the high-k dielectric according to the photoresist; and removing the photoresist thereafter. The removing of the photoresist includes using an organic solvent followed by removal of any residual photoresist including organic and/or carbon film. The removal of residual photoresist may include a degas process, alternatively known as a bake process. Alternatively, a nitrogen-hydrogen forming gas (i.e., a mixture of nitrogen and hydrogen) (N2/H2) or ammonia (NH3) may be used to remove the photoresist mask. With the use of the plasma nitrogen-hydrogen forming gas (N2/H2) or a plasma ammonia (NH3), no apparent organic residual is observed.