Epitaxial decagonal thin films on crystalline substrates

摘要

Al-Cu-Fe-Cr quasicrystalline thin films were grown on atomically flat Al_2O_3 sapphire (0001) substrates by single-target magnetron sputtering followed by annealing. A decagonal phase with the tenfold axis A_(10) parallel to the substrate surface normal was observed. The epitaxial decagonal film had two different unique orientations: a twofold P axis A_(2P) and a twofold D axis A_(2D) parallel to [1010] of the substrate. These two configurations were explained using a coincidence reciprocal lattice planes model for the interface energy. We show that this classic approach for crystal-crystal epitaxy can be applied to quasicrystal-crystal systems.