Advances in flip chip underfill material cure rates and reliability

This paper will focus on significant advances in improving flip chip underfill material cure rates under conventional cure mechanism and in improving the material's reliability, which significantly improves semiconductor packaging productivity. The material's cure rates as a function of time and temperature will be examined and presented by data generated by differential scanning calorimetry (DSC). DSC will also be used to examine the glass transition temperature of the optimum cure time and cure temperature. The material's linear coefficient of thermal expansion will be examined by thermomechanical analyzer (TMA). Other material physical properties such as shear strength and moisture absorption rate will be examined and presented. The reliability data from liquid-liquid thermal shock tests on actual flip chip devices using such material and optimum cure schedule will also be presented.