[Granted] A method of treating a photoresist relief feature having an initial line roughness and an initial critical dimension. The method may include directing ions toward the photoresist in a first exposure at a first angular range and first dose rate and a that is configured to reduce the initial line roughness to a second line roughness. The method may also include directing ions toward the photoresist relief feature in a second exposure at a second ion dose rate greater than the first dose rate, wherein the second ion dose rate is configured to swell the photoresist relief feature.