An integrated circuit (IC) package structure includes an electrical signal path, a low thermal resistance path and a substrate that includes a first device and a second device. The first device and the second device are part of an IC chip. The electrical signal path is from the first device to a top surface of the IC chip. The low thermal resistance path extends from the second device to the top surface of the IC chip. The low thermal resistance path is electrically isolated from the electrical signal path. The second device is thermally coupled to the first device by a low thermal resistance substrate path.