A Process-Structure Investigation of Aluminum Oxide and Oxycarbide Thin Films prepared by Direct Liquid Injection CVD of Dimethylaluminum Isopropoxide (DMAI)†

We present the direct liquid injection CVD of aluminum oxide and oxycarbide thin films using dimethylaluminum isopropoxide at high process temperature (500–700 °C) with the addition of O₂ gas, and at low temperature (150–300 °C) with the addition of H₂O vapor. Very smooth films with typical roughness values lower than 2 nm are obtained. The thin films are composed of an amorphous material. The composition evolves as a function of temperature from that of a partial hydroxide to a stoichiometric oxide at low deposition temperature (150–300 °C), and from that of a stoichiometric oxide to a mixture of an oxide with an (oxy) carbide at higher temperature (500–700 °C).