Embodiments described herein relate generally to methods for forming a mask for patterning a feature in semiconductor processing. In an embodiment, a dielectric layer is formed over a substrate. A mask is formed over the dielectric layer. Forming the mask includes depositing a first layer over the dielectric layer; implanting in a first implant process a dopant species through a patterned material and into the first layer at a first energy; after implanting in the first implant process, implanting in a second implant process the dopant species through the patterned material and into the first layer at a second energy greater than the first energy; and forming mask portions of the mask comprising selectively removing portions of the first layer that are not implanted with the dopant species.