MECHANISM OF FORMATION OF OXYGEN-CONTAINING LAYERS IN ALUMINUM NITRIDE

The mechanism of restructuring oxygen-containing defects in the 2H AlN layers parallel to the basal plane into 3.24-Angstrom-thick planar se gregations with the alpha-Al2O3-type lattice has been considered. Thes e segregations determine the formation of polytypes in the 2H AlN-O so lid solution. The mechanism suggested is based on the development of t he concept of the crystallographic Wadsley shear in oxygen-containing layers, resulting in the removal of the sublayer of aluminum-vacancies with the corresponding change of the coordination number of aluminum.