The surface topography of thin single‐crystal BaTiO3 films deposited on SrTiO3(100) and YBCO(001)/LaAlO3(100) substrates, and thin polycrystalline films deposited on MgO(100) was studied using scanning force microscopy in air. Films 0.37, 0.26, and 0.39 μm thick were grown on the SrTiO3(100) substrate at 750 °C at oxygen pressures of 0.7, 7, and 70 Pa, respectively. Films 0.47, 0.26, and 0.25 μm thick were deposited on the SrTiO3(100) substrate at the temperatures of 550, 750, and 850 °C, respectively, at an oxygen pressure of 7 Pa. Films 0.20 and 0.10 μm thick were grown on MgO(100) and YBCO(001)/LaAlO3(100) substrates, respectively, at 750 °C and 7 Pa. Scanning force microscopy images show that, for the deposition temperature of 750 °C, when the oxygen pressure is increased from 0.7 to 7 and 70 Pa, the surface topography of the BaTiO3 films changes from flat to islandlike three‐dimensional growth (Volmer–Weber mode), and the corresponding rms surface roughness values are 1.2, 3.4, and 6.4 nm. With an in...