Polishing of AlN/sapphire substrates obtained by thermochemical nitridation of sapphire

Abstract

Physicochemical conditions and polishing suspension composition were established for polishing of AlN/sapphire templates obtained by thermochemical nitridation of sapphire. The use of the polishing suspension based on aerosil and KOH with pH 10.3 allowed to prepare the surface with a roughness Ra up to 1 nm. The morphology and element composition of AlN/sapphire surface at layer-by-layer removal of the nitridated layer were studied by the methods of atomic force microscopy and X-ray photoelectronic spectroscopy.