MORPHOLOGY AND STRUCTURE OF TIO2 THIN-FILMS GROWN BY ATOMIC LAYER DEPOSITION

Atomic layer deposition of TiO2 films from TiCl4 and H2O was studied at reactor temperatures 100-500 degrees C. Amorphous films grew at temperatures below 165 degrees C, anatase structure was observed in the films grown at 165-350 degrees C while rutile dominated in the films obtained at temperatures above 350 degrees C. The surface morphology and optical losses of the films are related to the film structure. The highest surface roughness was observed at the temperature of amorphous to crystalline phase transition. The smoothest surfaces were recorded for amorphous films. The amorphous films grown at 100 degrees C had optical losses below 100 cm(-1) in the visible range of the spectrum.