A phased array has a laminar substrate, a plurality of elements on the laminar substrate forming a patch phased array, and integrated circuits on the laminar substrate. Each integrated circuit is a high frequency integrated circuit configured to control receipt and/or transmission of signals by the plurality of elements in the patch phased array. In addition, each integrated circuit has a substrate side coupled with the laminar substrate, and a back side. The phased array also has a plurality of heat sinks. Each integrated circuit is coupled with at least one of the heat sinks. At least one of the integrated circuits has a thermal interface material in conductive thermal contact with its back side. The thermal interface material thus is between the at least one integrated circuit and one of the heat sinks. Preferably, the thermal interface material has a magnetic loss tangent value of between 0.5 and 4.5.