PROCESS FOR THE SELECTIVE ENCAPSULATION OF AN ELECTRICALLY CONDUCTIVE STRUCTURE IN A SEMICONDUCTOR DEVICE

摘要

A process for fabricating an improved semiconductor device (10) is disclosed wherein a protective layer of Al2O3 (24) is selectively formed to encapsulate a refractory-metal conductor. (14) To form the Al2O3 layer,(24) first an Al/refractory-metal alloy (22) is selectively formed on the surface of the refractory-metal conductor, (14) then the Al/refractory-metal alloy (22) is reacted with O2. The resulting Al2O3 encapsulation layer acts (24) as an O2 diffusion barrier preventing the oxidation of the refractory-metal during subsequent process steps used to fabricate the semiconductor device. In addition, the Al2O3 layer (24) improves the mechanical compatibility of the refractory-metal conductor (14) with other materials used to construct the semiconductor device, such as, for example, improving the adhesion of an overlying layer of passivation glass to the refractory-metal conductor (14).