Semiconductor device fabrication using a sacrificial plug for defining a region for a gate electrode

摘要

A semiconductor device is formed by forming a sacrificial plug over a substrate and forming active regions in the substrate adjacent the sacrificial plug. A film is then formed over portions of the substrate adjacent the sacrificial plug. The sacrificial plug is then selectively removed leaving an opening in the film, and a gate electrode is formed in the opening. The sacrificial plug can be formed from several materials including, for example, polysilicon and nitrogen-bearing species such as nitride. The gate electrode may, for example, be formed from temperature-sensitive metals such as copper since the gate electrode may be formed subsequent to high temperature steps of the fabrication, such as a source drain anneal, for example.