Experimental Study on the Double-Sided Air Cooling for Integrated Power Electronics Modules

The objective of this work is to quantify the advantages of using double-sided cooling as the thermal management approach for the integrated power electronics modules. To study the potential advantage of the Embedded Power packaging method for the double-sided cooling, experiments were conducted. Three different cases were studied. To eliminate the effect of the heat sink on either side of the module, no heat sink was used in all three cases. The thermal tests were conducted such that the integrated power electronics modules were placed in the middle of flowing air in an insulated wind tunnel. Modules without additional top DBC, with additional top DBC, and with additional top DBC as well as heat spreaders on both sides were tested under the same condition. A common parameter, junction-to-ambient thermal resistance, was used to compare the thermal performance of these three cases. Despite the shortcoming of this parameter in describing the three-dimensional heat flow within the integrated power electronics modules, the concept of the thermal resistance is still worthwhile for evaluating various cooling methods for the module. The results show that increasing the top surface area can help in transferring the heat from the heat source to the ambient through the top side of the module. Consequently, the ability to handle higher power loss can also be increased. In summary, the Embedded Power technology provides an opportunity for implementing double-sided cooling as thermal management approach compared to modules with wire-bonded interconnects for the multichips.