Atomically smooth gallium nitride surfaces generated by chemical mechanical polishing with non-noble metal catalyst(Fe-Nx/C) in acid solution

In this paper, a novel method for preparing atomically smooth gallium nitride (GaN) wafer surfaces which involves chemical mechanical polishing with a non-noble metal catalyst (Fe-N_x) in acidic slurry is presented. It was confirmed that non-noble metal catalyst based slurry could be used for gallium face of GaN. Atomic force microscope images of the processed surface indicate that an atomically flat surface with Ra=0.0518 nm was achieved after planarization and the processed surface has an atomic step-terrace structure. Besides, the rate of removal of the GaN surface was measured to be approximately 66.9 nm/h, more than triple times higher than that nothing was used as catalyst.