Structural and electrical properties of Al2O3 film grown by mist chemical vapour deposition

Aluminium oxide (AlO
_x
) thin film was grown using aluminium acetylacetonate (AlAcac
₃
) as a source solute by mist chemical vapour deposition (CVD). The AlO
_x
thin film grown at 430°C exhibited the breakdown field (E
_BD
) and the dielectric constant (k) of 5.9 MV/cm and 6.8, respectively. It was suggested that the formation of boehmite (γ-AlO(OH)) in the films decreased the E
_BD
of AlO
_x
thin films at the growth temperatures below 350°C. In the mist CVD, the reaction proceeded efficiently (E
_a
= 23.5-26 kJ/mol) under the evaporated solvent atmosphere. The AlO
_x
film was able to be grown at 430°C with high deposition ratio (18 nm/min) and smooth surface (RMS =1.6 nm).