EPITAXIAL-GROWTH OF MO SINGLE-CRYSTAL ON SAPPHIRE BY H-2 REDUCTION OFMOO3 AND CHARACTERIZATION BY REFLECTION HIGH-ENERGY ELECTRON-DIFFRACTION

Mo depositions on sapphire (Al2O3) were effected by H-2 reduction of M oO3, and the crystallinity of the films was characterized by reflectio n high-energy electron diffraction (RHEED). In the case of growth on t he (1 ($) over bar 102) Al2O3 substrates, single-crystal epitaxial gro wth of (001) Mo was realized. On (0001) Al2O3, single-crystal Mo was n ot obtained; Mo deposited on (0001) Al2O3 was composed of three sets o f (110)-oriented crystallites. To obtain Debye-Scherrer ring-free Mo f ilms whose RHEED patterns did not include arcs, growth temperatures of 890 and 920 degrees C were required in growths on (1 ($) over bar 102 ) and (0001) Al2O3 substrates, respectively.