Pressureless Direct Bonding of Au Metallized Substrate with Si Chips by Micro-Ag Particles

The aim of this work is to develop and investigate bare Si chips assembly to Au plated substrates. In this research thermal interface material paste based on mixture of micro-Ag particles and pressureless sintering at 175 degrees C was studied. Joints obtained in the experiments had adhesion of 10 MP a and thermal resistance as low as 0.25 K/W. Novelty of this work is application of micro Ag paste at low temperature process and without pressure applied on the chip. Those parameters are usually shown as limitation of Ag paste applications. Additionally, after ageing for 500 h at 125 degrees C and thermal cycles (-20 degrees C +/- 100 degrees C) investigated joints maintained their mechanical and thermal properties.