Anomalous effect of temperature on atomic layer deposition of titanium dioxide

A strong influence of growth temperature on the deposition rate and refractive index of TiO2 thin films, grown by atomic layer deposition from TiCl4 and H2O was observed. The growth rate increased from 0.05 to 0.09 nm per cycle while the refractive index decreased from 2.83 to 2.00 with the increase of growth temperature from 150 degreesC to 225 degreesC. The effect was due to crystallization processes starting at these temperatures. The substrate temperature range, in which the growth rate most significantly changed, depended on the TiCl4 pulse time. (C) 2000 Elsevier Science B.V. All rights reserved.