Semiconductor device fabrication with planar gate interconnect surface

Abstract

In accordance with principles of the invention, there is provided a new process for semiconductor device fabrication. The disclosed process includes forming field isolation regions on a surface of a silicon wafer, and forming gate oxide regions selectively between the field isolation regions. A gate interconnect material is deposited over the field isolation regions and gate oxide regions. A planar surface is formed on the top of the gate interconnect material. This planarization step may be accomplished by chemical mechanical polishing or some other convenient method such as a resist etch back. After planarization of the gate interconnect material, a uniform thickness photoresist is deposited on the planar surface. A gate interconnect etch pattern is formed on the planar surface using photolithography and the gate interconnect material is etched to match a gate interconnect pattern and the photoresist is removed. Sidewall spacers are provided. A silicide is formed over the top of the gate interconnect and over the diffusion areas.