A new concept for using of Al-sheet as integrated substrate for one or multichip module package

In this paper, we present recent studies on the electromigration processes in Ag thin film parallel microstrip lines in MCM-D structures. The basic concept is application of accelerated local drop-tests of water solutions on the surfaces of two adjacent lines under a given voltage potential. These operational conditions are often met in the interconnection line buses placed in the top assembly level of multilayered hybrid structures. The subject of the investigations are MCM-Ds developed on an Al-sheet carrier with internal conducting and isolating layers, produced through unique selective electrochemical anodization of Al and Ta. This process technology also enables the creation of embedded R and C passive components based on TaO_xN_1-x and Ta₂O₅ (or Al ₂O₃) respectively. We propose electrochemical deposition of Ag/Sb alloys on the surface of Al interconnection lines and contact pads to ease the bondability and solderability in chip mounting procedures. The artificially created silver migrated defects and partial shorts are investigated through the high frequency method of coupled transmission lines in order to eliminate the errors and insufficient validity of DC direct measurements