METHOD FOR FORMING METAL DAMASCENE GATE

摘要

PURPOSE: A method for forming a metal damascene gate is provided to prevent the damage of a dummy polysilicon by CMP(Chemical Mechanical Polishing) using a CeO slurry. CONSTITUTION: After forming a gate oxide(2) on a silicon substrate(1), a dummy polysilicon gate(3) is formed on the gate oxide(2). Source and drain regions(5) are formed in the silicon substrate. Spacers(4) are formed at both sidewalls of the dummy polysilicon gate(3). After depositing an interlayer dielectric(6) on the resultant structure, the surface of the dummy polysilicon gate(3) is exposed by CMP using CeO slurry having high polishing selectivity against the polysilicon. A silicon-contained oxide formed on the dummy polysilicon gate(3) is then removed by wet-etching.