The formation mechanism of the partially crystallized ultrathin layer at the interface between GaN and SiNx grown by low-pressure chemical vapor deposition was analyzed based on the chemical components of reactants and products detected by high-resolution sputter depth profile analysis by X-ray photoelectron spectroscopy. A reasonable mass action equation for the formation of Si2N2O was proposed from the feasibility analysis of the Gibbs free energy changes of the reaction. The high-energy-activated Ga2O on the surface likely assists in the synthesis of the crystallized components. A well-defined 1ML θ-Ga2O3 transition interface was inserted into Si2N2O/GaN pure interface supercell slabs to edit the unsaturated state of the bonds. Low-density states can be achieved when the effective charges of the unsaturated atoms are adjusted to a certain interval.
Keywords: GaN; LPCVD-SiNx; first-principles; formation mechanism of crystallized Si2N2O; interface editing; near-conduction band states.