Crystalline titanium oxide films with a thickness of 0.09±0.55 lm were prepared at temperatures below 500 C by CVD using a mixture of titanium tetrachloride (TiCl 4 ), carbon dioxide (CO 2 ), and hydrogen (H 2 ) as reactants. Film thickness decreased with increasing substrate temperature and CO 2 /H 2 input. Nanosized microstructure was obtained at high CO 2 /H 2 input due to the growth retardation of reacted HO-TiCl 3 * by the unreacted TiCl 4 and CO 2 . That film composition, i.e., the O/Ti ratio, increased with temperature and the CO 2 /H 2 input can be explained by growth kinetics. Unlike film thickness, internal film stress increased with increasing substrate temperature. Adhesion was controlled by compressive internal stress due to the weak bonding between film and substrate. Two growth mechanisms are proposed to explain the tensile and compressive stress states in films produced by CVD. The adsorption-controlled reaction has a film in compressive stress that increases with an increase in temperature. On the other hand, thermally activated CVD produces a film in tensile stress that decreases with an increase in substrate temperature.

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Amorphous aluminum titanate films are prepared on silicon substrates by low-pressure chemical vapor deposition (CVD) using a mixture of aluminum tri-sec-butoxide (ATSB), titanium tetrachloride (TiCl4), CO2, and H2 as the reactants (the ATSB/TiCl4/CO2/H2 system). The effects of the CO2/H2 and ATSB inputs and substrate temperature on the growth, microstructure, and composition of the CVD Al2O3–TiO2 films are discussed. The films have an increased growth rate and an increased Ti content at lower temperatures. The adsorption-controlled reaction is identified, which is attributed to the gas/solid reaction to weaken the film/substrate interface. The growth rates are also higher at higher H2 and ATSB flows. The film thickness is 0.47–1.13 μm for the CO2/H2-varying system and of 0.34–1.37 μm for the ATSB-varying system at deposition temperatures of 350–500 °C. The proposed reactions are presented to explain the film growth. The determined adsorption energy can explain the effect of temperature on composition.