High Growth Rate in Atomic Layer Deposition of TiO2 thin films by UV Irradiation

The exposure effect of the reaction surface to ultraviolet (UV) light was studied for atomic layer deposition (ALD) of TiO2 films from Ti((OPr)-Pr-i)(4) and H2O at 260 degrees C. UV light was irradiated on the reaction surface after the purge step of Ti-precursor and oxygen source, respectively. UV irradiation on the reaction surface resulted in a higher growth rate of the TiO2 films compared to the thermal ALD. The growth rate of anatase TiO2 increased by a factor of 2 to about 0.25 nm/cycle while the surface roughness was reduced. UV-light induced increase of the number of chemisorption sites is discussed as the possible mechanism. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3534833] All rights reserved.