碳纳米管-石墨烯增强纳米Ag膏低温连接功率芯片

Nano-Ag sintering is an ideal sintering materials for third-generation wide-band gap semiconductor chip packaging due to its excellent thermal conductivity and high temperature resistance. How to choose a suitable second phase to stabilize the evolution of the sintered layer structure during high-temperature operation is one of the important challenges of Ag sintering technology. In this paper, carbon nanotube-graphene (CNT-G) was used to reinforce the nano-Ag paste. The sintered microstructure, shear strength, and the influence of the added phase were analyzed. Results show that the decomposition temperature of CNT-G reinforced nano-Ag paste is 250 ℃, and the content of Ag and CNT-G is 93% (mass fraction). As sintering temperature increases, more and more particles form sintering necks, which gradually increases the density of the sintered body. The CNT-G reinforced nano-Ag paste can realize bonding SiC chip and DBC substrate at temperature of ≥230 ℃ and sintering pressure of 5 MPa.