It is very difficult to produce a smooth and damage-free gallium nitride(GaN) surface using the conventional polishing method utilized for silicon wafer processing because of the hardness,brittleness and chemicalinertness of GaN.We have developed a novel polishing method named CARE(catalyst-referred etching),which is an abrasive-free chemical polishing method involving a chemical reaction between the surface of a workpiece and a catalytic plate in a chemical solution or pure water.Here,we report that a GaN substrate with a damage-free and atomically smooth surface can be obtained by the CARE process
