A UV radiation sensor that includes an area that is filled with a dielectric material, the area comprises a first portion of a first thickness and a second trench portion with dielectric of a second thickness, wherein the first thickness is smaller than the second thickness; a floating gate that comprises a first floating gate portion that is positioned above the first area portion and a second floating gate portion that is positioned above the trench portion, wherein the second floating gate portion comprises multiple segments, wherein there are one or more gaps between two or more of the multiple segments; a charging element for charging the floating gate; and a readout element for reading the floating gate.