Anatase and rutile TiO2 thin films were prepared by chemical vapor deposition with precursors Ti(OPri)(4) and Ti(dpm)(2)(OPri)(2) (dpm = 2,2,6,6-tetramethylheptane-3,5-dione and Pr-i = isopropyl), respectively. The dielectric properties of TiO2 thin films have been studied in 20-1100 K temperature range in air, in controlled Ar/O-2 atmospheres, and in vacuum with silicon-based metal-insulator-semiconductor Au/TiO2/Si capacitors. High-temperature (T-c similar to 980 K) anomalous behavior of dielectric constant was observed in both anatase and rutile TiO2 thin films. (C) 2009 Elsevier Ltd. All rights reserved.