In one embodiment, a method includes forming a structure having a first region including a ceramic material, a second region including a plurality of particles disposed in a ceramic matrix material, and a magnetic head assembly disposed in the first region. The method also includes directing a first ion beam at a side of the first and second regions of the structure, the first ion beam including an oxidizing species to oxidize one or more portions of the particles located near the side of the second region, where the one or more oxidized portions of the particles protrude from the side of the ceramic matrix material of the second region. The method further includes directing a second ion beam at the side of the first and second regions of the structure, the second ion beam including an inert species to recess the first and second regions.