Hybrid substrate - A future material for power semiconductor modules

Abstract:
The increasing level of integration in semiconductor power modules has led to higher power densities that in turn results in an increased need for better thermal management. Lately, liquid cooling is attracting more attention in the industry as a method to ensure the higher performance and reliability of these modules. This paper introduces a hybrid substrate comprising of copper, ceramic and aluminum that combines the thermal & electrical performance of the copper with the corrosion resistance of aluminum using a ceramic dielectric. In this manner, the aluminum can be directly contacted to the cooling water to improve cooling efficiency without worry about corrosion, while the copper portion can be used for the circuit, leveraging its superior current carrying and heat spreading capabilities. This paper reports on the work to develop such a hybrid substrate by bonding aluminum to the back side of DBC using an adhesive and to explore its application in power electronics.