Thermal Analysis of Ceramic-Based and FR4-Based Planar Coils

With higher power levels and smaller volumes, FR4-based planar coils face challenges in heat dissipation. Ceramic materials have become the alternative to FR4 for planar coils in recent research. This paper provides a thermal analysis considering the effects of contact thermal resistance between the copper and isolation layers of planar coils. Based on the proposed thermal model, ceramic materials will have better thermal performance compared to FR4 with same contact thermal resistance due to higher thermal conductivity, which are verified by experiments. Furthermore, the test results reveal that contact thermal resistance has a significant effect on the thermal performance of planar magnetics, which may become an essential parameter for the future thermomechanical research.