A method includes forming first, second, and third conductive leaf structures. The first conductive leaf structure includes a first conductive midrib and conductive veins. The second conductive leaf structure is electrically connected to the first conductive leaf structure, and includes a second conductive midrib, conductive veins extending toward the first conductive midrib, and conductive veins extending away from the first conductive midrib. The third conductive leaf structure includes a third conductive midrib between the first conductive midrib and the second conductive midrib, conductive veins extending toward the first conductive midrib, and conductive veins extending toward the second conductive midrib.