Peculiarity of self-assembled cubic nanolamellae in the TiN/AlN system: Epitaxial self-stabilization by element deficiency/excess

摘要: Abstract Synthesis of self-assembled thin films with multi-layered microstructures and outstanding functional properties represents a challenging task. In this work, detailed microstructural chemical analyses ∼3.8 μm thick cubic (c) (Al x Ti 1- ) y N film grown by low pressure vapour deposition on Al 2 O 3 (0001) substrate is discussed. The an overall fraction ∼0.8 consists alternating non-stoichiometric Al-rich Ti-rich nanolamellae thicknesses ∼11 ∼1.5 nm. X-ray diffraction, electron microscopy energy loss spectroscopy indicate that the coherency primarily result deficiency in excess nanolamellae, which induce decrease increase lattice parameters, compared to parameters stoichiometric rock-salt c-TiN c-AlN, respectively. Therefore self-assembly allows formation c-(Al atomic 0.9–1.0, are stabilized neighbouring as cube-on-cube epitaxy. effect parameter self-adjustment coherent element verified ab initio calculations. compositional morphological matches interfaces at grain boundaries, terraced growth tetrahedral surface morphology unzipped facets well uniform thickness across depth formed kinetically-controlled oscillating reactions during growth. understanding fascinating nanolamellar microstructure containing meta-stable c-AlN , does not exist bulk form ambient conditions, milestone technology.