A semiconductor structure includes a first metal-dielectric-metal layer, a first dielectric layer, a first conductive layer, a second conductive layer, and a second dielectric layer. The first metal-dielectric-metal layer includes a plurality of first fingers, a plurality of second fingers, and a first dielectric material. The first fingers are electrically connected to a first voltage. The second fingers are electrically connected to a second voltage different from the first voltage, and the first fingers and the second fingers are arranged in parallel and staggeredly. The first dielectric material is between the first fingers and the second fingers. The first dielectric layer is over the first metal-dielectric-metal layer. The first conductive layer is over the first dielectric layer. The second conductive layer is over the first conductive layer. The second dielectric layer is between the first conductive layer and the second conductive layer.