We studied supercritical carbon dioxide fluid deposition of titanium oxide (TiO2) in trench features on Si substrates using a flow-type deposition apparatus from titanium diisopropoxide bis(dipivaloylmethanate), aiming at fabricating conformal films at a relatively low temperature. We investigated the deposition rate and step coverage under a fluid temperature from 40 to 60 degrees C, a pressure from 8.0 to 10.0 MPa, and a substrate temperature from 80 to 120 degrees C. They were dependent on the fluid density, indicating that the solubility difference between the bulk fluid and the neighborhood of the substrate surface plays a decisive role for the deposition. An excellent conformal filling of the trench features was achieved from the fluid of 60 degrees C under 8 MPa on the substrate kept at 80-100 degrees C. The XPS spectra of the deposited film suggested partial formation of TiO2, and the XRD spectra showed the existence of some crystalline TiO2 (anatase). (C) 2009 Elsevier B.V. All rights reserved.