The atomic layer deposition technique has been applied to the growth ofAl2O3thin films on the substrates of Si(100), 100-nm-thickSiO2covered Si(100)[SiO2/Si(100)],and 90-nm-thick TiN coveredSiO2/Si(100).The growth rate ofAl2O3films was 0.19 nm/cycle and identical for all substrates employed under the surface controlled process. However, the optical properties ofAl2O3films were significantly affected by different substrates. The average interband-oscillator energy and refractive index parameter were determined to be 3.330 eV and2.992×10−14 eV m2forAl2O3film grown on Si(100), while those for the film grown onSiO2/Si(100)were 4.492 eV and2.074×10−14 eV m2,respectively. ©1997 American Institute of Physics.