(006)-oriented α-Al2O3 films prepared in CO2–H2 atmosphere by laser chemical vapor deposition using a diode laser

Abstract

Abstract (0 0 6)-oriented α-Al2O3 films were prepared by laser chemical vapor deposition (LCVD) using aluminum acetylacetonate (Al(acac)3) in CO2–H2 atmosphere. The effects of the CO2 mole fraction ( F CO 2 ) and laser power (PL) on the crystal phase, microstructure, and deposition rate (Rdep) were investigated. α- and γ-Al2O3 mixture films were prepared at PL = 90 W (deposition temperature of 818 K), whereas (0 0 6)-oriented single-phase α-Al2O3 films were obtained at PL = 110 W (863 K). The texture coefficient and the grain size of the (0 0 6)-oriented films increased with increasing F CO 2 . The orientation of the α-Al2O3 films changed from (0 0 6) to (1 0 4) to (0 1 2) with increasing PL (Tdep). The Rdep of the (0 0 6)-oriented α-Al2O3 films increased with increasing F CO 2 .