Developing the chemistry of novel scandium β-diketonates for the MOCVD of scandium-containing oxides

Thin films of scandium oxide, Sc2O3, have been deposited by liquid-injection MOCVD using tetrahydrofuran solutions of the novel precursors Sc(tmod)(3) (tmod = 2,2,7-trimethyloctane-3,5-dionate) and Sc(mhd)(3) (mhd = 6-methylheptane-2,4-dionate). The properties of the films are compared to those of films grown using the conventional precursor Sc(thd)(3) (thd = 2,2,6,6-tetramethyl-3,5-heptanedionate). Oxide growth was observed over a wide range of substrate temperatures, from 400 degrees C to at least 600 degrees C, and the films were shown (by Auger electron spectroscopy) to be Sc2O3 With no detectable carbon impurity. The properties of the scandium beta-diketonates were found to vary with the nature of the beta-diketonate group and the use of the asymmetric tmod and mhd groups led to precursors with lower melting points and higher volatilities than the Sc(thd)(3) source.