Method of Fabricating Gold Interconnections With Tantalum-Coated Vertical and Horizontal Surfaces
Original Publication Date: 1984-Feb-01
Included in the Prior Art Database: 2005-Feb-02
Gold (Au) interconnection lines that are tantalum (Ta) coated on both vertical and horizontal surfaces will have higher reliability than conventional structures that are coated only on the horizontal surfaces. In this process the structure shown in Fig. 1 can be fabricated by the standard process. A layer 10 of SiO2 or other dielectric is deposited on a silicon substrate 12, and a blanket layer of TiW 14 is deposited on layer 10. A blanket layer of Ta 16, an overlying blanket layer of Au 18 and a second layer 20 of Ta is deposited on layer 14, and the desired metallurgy configuration subtractively etched by conventional photolithographic and etching techniques. The laminated stripe 22 shown in cross section can also be formed by reactive ion etching techniques.