Atomic layer deposition of TiO2 from TiCl4 and O3

Abstract Atomic layer deposition (ALD) of thin films from TiCl 4 and O 3 on Si(100) substrates was investigated. The growth of TiO 2 was obtained at substrate temperatures of 225–600 °C from these hydrogen-free precursors. Formation of anatase phase in the films was observed at 250–600 °C. In addition, the rutile phase was revealed in thicker films deposited at 600 °C. Compared to the well studied TiCl 4 –H 2 O ALD process the TiCl 4 –O 3 process allowed higher growth rate at 275–600 °C. In addition, relatively low surface roughness was obtained for thicker (> 50 nm) films of the anatase structure deposited from TiCl 4 and O 3 at 350–400 °C. Therefore TiCl 4 and O 3 appeared to be a good precursor combination for ALD of TiO 2 , particularly for applications that require low concentration of hydrogen contamination.