An integrated circuit includes an oxide layer over a substrate; a layer of semiconductor material over the oxide layer and which includes a P-well, an N-well, and a channel of a transistor; and a thermal substrate contact extending through the layer of semiconductor material and the oxide layer, and against a top surface of the substrate. A thermal substrate contact increases the ability to remove heat produced from the integrated circuit transistors out of the integrated circuit. A thermal substrate contact which traverses the oxide layer over a substrate provides a secondary path for heat out of an integrated circuit (or, alternatively, out of a substrate through the integrated circuit) to cool the integrated circuit.