In a method is provided for removing a material from a substrate, a plasma is generated at atmospheric pressure. The plasma includes an energetic species reactive with one or more components of the material. The plasma is flowed from an outlet as a plasma plume that includes periodic regions of high plasma density and low plasma density. The material is exposed to the plasma plume. At least one component of the material reacts with the energetic species, and at least one other component of the material is physically impacted and moved by one or more of the regions of high plasma density.