In one embodiment, a circuit board is disclosed. The circuit board includes a first metal core; a second metal core spaced apart from the first metal core in a first direction when viewed as a cross section, such that a first side of the first metal core faces a first side of the second metal core; a first electrode electrically connected to the first side of the first metal core; a second electrode electrically connected to the first side of the second metal core facing the first metal core; and a dielectric layer between the first and second electrodes.