Material properties of very thin electroless silver-tungsten films

Thin electroless silver-tungsten (Ag-W) films were deposited on silicon dioxide substrate from the benzoate solution. The layer composition and microstructure as well as the film deposition rate were studied as a function of the bath formulation. The tungsten concentration in the deposit was up to similar to 2.1 atm% with corresponding oxygen concentration approximately 4 atm%. It was found that electrical, optical, and mechanical properties of Ag-W films depend on the W content in the deposit. Ag-W films of sub 120 nm thickness with similar to 0.6 atm% tungsten and 1.8 atm% oxygen have demonstrated the resistivity of similar to 4 muOmega.cm. Finally, the possibility to use the Ag-W thin films for microelectronic metallization is discussed. (C) 2003 Elsevier Science B.V. All rights reserved.