Critical thickness for transformation of epitaxially stabilized cubic AlN in superlattices
نویسندگان
چکیده
The epitaxial stabilization and transformation of cubic AlN layers in AlN/VN and AlN/TiN superlattices, grown by reactive sputtering on MgO ~001!, is described. In AlN/VN, the critical AlN thickness l for transformation from cubic to hexagonal increased from '3.0 to .4 nm when the VN superlattice layer thickness was increased from 2.0 to 6.0 nm. The effect of lattice mismatch was observed by comparing AlN/VN (mismatch51.46%) and AlN/TiN (mismatch53.84%). The l values were smaller, 2–2.5 nm, for the larger mismatch AlN/TiN system. The dependence of l on the lattice mismatch and stabilizing layer thickness is discussed based on models of epitaxial stabilization. © 2001 American Institute of Physics. @DOI: 10.1063/1.1345831#
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