Microstructure-related resistivity change after chemical-mechanical polishof Al and W thin films

The correlation between microstructures of Al and W metal thin films and th eir respective chemical-mechanical polishing (CMP) performance is investiga ted. It is found that CMP removal rate decreases with increasing grain size . In both cases, the textures of the metal films are altered and their resi stivity increased after CMP. The phenomenon is more pronounced for polish u nder a greater down-force. The table speed, on the other hand, has only min imum effects on microstructure and resistivity. The possible underlying mec hanisms leading to this phenomenon are proposed and their potential impact on metallization reliability is discussed. (C) 2000 Elsevier Science S.A. A ll rights reserved.