Oxidizable Refractory Metal Silicide Structure and Technique
Original Publication Date: 1984-Sep-01
Included in the Prior Art Database: 2005-Feb-04
In the fabrication of refractory metal silicide films, such as the gate electrode of a metal oxide semiconductor field-effect transistor (MOSFET), a serious yield problem exists when the silicide films are oxidized for passivation. Rough oxide, formed by localized internal oxidation and decomposition of the silicide, causes rupture of the silicide film and complete failure of devices over large areas of a wafer. The same problem exists in the application of silicides to integrated circuit interconnections. A technique which easily solves this problem is to deposit a thin layer of silicon 11 on top of the silicide 12 structure. This eliminates the reliance of the diffusional supply of silicon atoms from the underlying silicide layer. The thermally formed oxide 13 will be almost entirely converted from the top silicon layer.