First-principles analysis of Catalyst-referred etching of GaN surface with Pt catalyst

Reactions at kink site on Ga surface

Abstract

Etching process of GaN surface by water molecules with a catalytic assist of Pt was investigated by means of the first-principles reaction path and barrier analysis. By approaching Pt to GaN surface, water molecules in between the two surfaces are found to be dissociatively adsorbed at the kink site of GaN surface. Interaction with Pt strongly reduces reaction barrier height. After the dissociative adsorption of the second water molecule, Ga atom initially at kink site is transformed into Ga(OH) ₃ molecule and become almost removed from the surface.