Selective growth of aluminum using a novel CVD system

Selective growth of aluminum with smooth surface topography is realized using a double-wall CVD (chemical vapor deposition) system in which the substrate is positioned between two heaters with different temperatures. Aluminium is deposited selectively onto silicon, metals, and silicides of the substrate; no deposition occurs on the SiO/sub 2/ surface. This technique is available for filling high-aspect via holes in multilevel metallization systems. Al/polySi two-layer interconnections with 0.4- mu m-diameter via holes have been successfully fabricated using selective aluminum deposition and a self-aligned TiSi/sub 2/ formation technique. >