Increased lifetime of wire bonding connections for IGBT power modules

In power transmission, industrial and traction applications IGBT modules are required to reach a high lifetime while operating under severe working conditions and in harsh environments. Therefore, ABB is taking care of reliability and lifetime requirements at the early stages of the modules' packaging design and development. This paper deals with the wire bonding interconnection technology used in power IGBT modules and the specific failures related to thermal fatigue phenomena. A technology comparison is performed for wire bonding: with and without a polymer bond coating as well as bonding on strain buffer. The potential of these different technologies to enhance reliability and lifetime is assessed.