Vascular Polymer Encapsulation for Integrated Thermal Management and Packaging of Electronics

Two of the critical requirements for electronic systems are that they be protected from the environment and thermally regulated. Generally, these two tasks are accomplished separately, with a plastic or metal enclosure for protection and a separate cooling plate for thermal regulation. Vascular encapsulation of electronics is proposed here as a method developed for integrated packaging and thermal management of these systems. The proposed method allows for tighter system integration in applications where electronics with different power and temperature ratings are in proximity of each other or are adjacent to other heat sources such as power electronics converters and electric machine-drive circuitries. In vascular encapsulation, the delicate electronic systems are overmolded with a structural polymeric material containing an embedded network of small channels. The polymer provides physical protection while the channel network allows for thermal regulation by liquid cooling. Formation of the channels within the module utilizes a new method for sacrificial fabrication, Deflagration of Sacrificial Components (DeSC), wherein a specially designed sacrificial material is removed by combustion to convert the solid material to a gas without damaging the polymer or electronics. In this paper, the design and fabrication of a simple vascular encapsulated electronics module containing an array of eight thick film resistors is discussed. The cooling performance of the vascular system is then compared to that of a commercial liquid cooling plate. Results show that the vascular system’s cooling capability meets that of the commercial system with a significant reduction of system mass and volume of 80%.