Influence of Nature of Filler on Densification of Anorthite-Based Crystallizable Glass plus Ceramic System for Low Temperature Cofired Ceramics Application

Abstract

This paper deals with the critical aspects of sintering of crystallizable glass+ceramic system, which is a critical part of low-temperature-cofired ceramics (LTCC) process. Densification studies clearly revealed the influence of filler's nature especially at lower glass contents (<= 70 vol%) and lower sintering temperatures. In this temperature range, marked improvement in density was observed in the order cordierite > fused silica > mullite > alumina. The decisive role played by wetting of glass on filler has been demonstrated using heating microscopy and wetting studies. However, densification was not influenced by the nature of filler at higher glass contents (> 70 vol%) and at higher sintering temperatures. This is because in this range of glass content viscous flow of glass dominates the wetting behavior. This paper brings out the salient features responsible for the sintering behavior of anorthite glass+ceramic LTCC composition.