Effect of metal oxide precursor on sintering shrinkage, microstructure evolution and electrical properties of silver-based pastes

Abstract

Since the shrinkage behavior of silver-based films has been correlated with the characteristics of oxide additives used, the relative role of metal oxides and metal-organic precursors in sintering shrinkage and microstructure evolution of silver films was investigated and compared in this work. Films with an oxide powder additive exhibit two-stage shrinkage behavior in contrast to one-stage continuous shrinkage, which occurs in silver films with metal-organic precursors, added. Furthermore, metal-organic precursors are less effective than metal oxide powders in reducing shrinkage of silver-based films. That can be reasonably explained that metal-organic precursors can be effectively decorated around silver powder to inhibit the sintering densification. The Zr-based organic precursor among the metal-organic precursors exhibits optimal retardation in sintering densification of silver film, which is probably interrelated to refractory characteristics of ZrO2. The unique conductivity and grain growth of silver film with 1.0 wt% tungsten-organic precursor added was possibly due to the partial dissolution of W into Ag. (C) 2002 Kluwer Academic Publishers.