Method for manufacturing a gate electrode of a mos transistor

Abstract

A method for manufacturing an electrode, e.g., a gate electrode of a MOS transistor, and an electrode and MOS transistor manufactured in accordance with this method. The method includes the steps of forming a first diffusion preventing layer on an underlying layer, forming a mask pattern having an opening on the first diffusion preventing layer, forming a metal layer on a portion of the first diffusion preventing layer exposed by the opening in the mask pattern, forming a metal layer on the exposed portion of the first diffusion preventing layer, forming a second diffusion preventing layer on the resultant structure, etching back the second diffusion preventing layer to leave a remaining portion thereof on the metal layer, removing the mask pattern, and forming a third diffusion preventing layer on exposed portions of the remaining portion of the second diffusion preventing layer, exposed sidewalls of the metal layer, and exposed portions of the first diffusion preventing layer. Preferably, the first, second, and third diffusion preventing layers are comprsied of titanium nitride, and the metal layer is comprised of copper.