| abstract |
A process and structure for enhancing electromigration resistance within a copper film using impurity lamination and other additives to form intermetallic compounds to suppress metal grain boundary growth and metal surface mobility of a composite copper film. The present invention provides an alloy seed layer and laminated impurities to incorporate indium, tin, titanium, their compounds with oxygen, and their complexes with oxygen, carbon, and sulfur into other films. The intermetallics form and segregate to grain boundaries during an annealing process to reduce copper atom mobility. A further aspect of the present invention is the use of high-temperature, inter-diffusion of additives included in an alloy seed layer to form a barrier layer by combining with materials otherwise unsuitable for barrier material functions. |