Implementations described herein relate to methods for forming gap fill materials. After the gap fill material is deposited and before a CMP process is performed on the gap fill material, one or more ion implantation processes are utilized to treat the deposited gap fill material. The one or more ion implantation processes include implanting a first ion species in the gap fill material using a first ion energy, and then implanting a second ion species in the gap fill material using a second ion energy that's lower than the first ion energy. The one or more ion implantation processes minimize CMP dishing and improve recess profile.