Preparation of Li-Al-O films by laser chemical vapor deposition

Li-Al-O films were prepared on AlN substrates by laser chemical vapor deposition at deposition temperatures (Tdep) of 800-1300 K and molar ratios of Li to Al precursors (RLi/Al) of 0.1-12. Single-phase α-LiAl5O8 films having faceted grains with pyramidal and polygonal shapes were obtained at Tdep = 1107-1280 K and RLi/Al = 0.1-2.9. Single-phase γ-LiAlO2 films having pyramidal grains were prepared at Tdep = 984-1238 K and RLi/Al = 0.9-10.6. Under the conditions of Tdep = 923 K and RLi/Al = 11.4, single-phase β-Li5AlO4 films with a fluffy morphology were deposited. The highest deposition rate of Li-Al-O films was 98 μm h−1 with a mixture of γ-LiAlO2 and β-Li5AlO4 at Tdep = 944 K.