Atomic layer deposition of TiO2 films was realized by using alternate pulses of TiI4 and O2. The film growth mechanism was studied by quartz crystal microbalance in the temperature range 200-350 °C. The adsorption of TiI4 proceeded via partial decomposition of TiI4, which resulted in an enhanced reactivity by the formation of a TiIx surface layer with x < 3. The reactivity of O2 toward this layer was sufficient to form TiO2 at an O2 pulse duration of 2 s when the substrate temperature was not lower than 235 °C. TiO2 films were also grown on Si(100) substrates at deposition temperatures between 230 and 460 °C. No residual iodine could be detected in the films grown at temperatures higher than 230 °C. Phase-pure anatase was formed in the whole temperature range except at the highest temperature where rutile was also obtained.

The mass thickness of thin titanium oxide and hafnium oxide films grown by the atomic layer deposition method on silicon substrates was determined using EPMA data and STRATA and FLA programs. The results of the two programs coincided well if a set of relative intensities was measured at different energies of probe electrons. Comparative measurements by XRF gave higher values. Comparing the mass thicknesses of films measured by EPMA and absolute thicknesses determined by optical spectrophotometry, ellipsometry and profilometry, the densities of polycrystalline films were estimated. Values of 3.3±0.2 and 8.7±0.2 g cm−3 were obtained for TiO 2 anatase grown at 300 °C and monoclinic HfO 2 grown at 600 °C, respectively. Titanium oxide films deposited at 100 °C contained significant amounts of chlorine and hydroxyl groups (7.2±0.7 and 6.9±0.9 mass-%, respectively).had HfO 2 stripes on a silicon substrate. The film was deposited