Band gap energy in nanocrystalline ZrO2:16%Y thin films

The results of optical absorption measurements on nanocrystalline ZrO2:16%Y thin films are presented. Dense 0.7 mu m thick films with 1-300 nm grain size have been obtained on sapphire substrate using a polymeric precursor spin coating technique. The relationship between the energy gap and microstructure of ZrO2:16%Y has been determined and discussed. The quantum confinement effect was observed at the grain size lower than 100 nm with the band gap energy shift of 0.25 eV when the microstructure was changed up to 1 nm. Some limitation of the model has been observed and discussed. The band gap energy of 5.62+/-0.05 eV has been determined as microstructure independent value. (C) 1999 American Institute of Physics. [S0003-6951(99)01003-7].