A photomask includes a transparent substrate for passage of an exposure light, and a plurality of photomask pattern units formed on a surface of the transparent substrate. Each of the photomask pattern units includes a first light-blocking layer connected to the surface of the transparent substrate, and a second light-blocking layer formed on a surface of the first light-blocking layer opposite to the transparent substrate. The first and second light-blocking layers block the exposure light, or permit passage of light energy lower than threshold energy of photoresist on the substrate.