Photoluminescent characteristics of hafnium oxide layers activated with trivalent terbium (HfO₂:Tb⁺³)

Hafnium oxide layers doped with trivalent terbium ions have been synthesized using the ultrasonic spray pyrolysis technique. Photoluminescence properties were studied as a function of growth parameters such as the substrate temperature and the terbium concentration. The films were grown starting from aqueous solution of Hafnium and Terbium chlorides. The results show that crystalline structure of HfO2:Tb+3 films depends on the temperature. Emission and excitation spectra were obtained for the HfO2:Tb+3 films using 262nm as the excitation wavelength. All emission spectra show bands centered at 488, 542, 584 and 621nm, which correspond to the electronic transitions: 5D47Fj (j=3, , 6) characteristic of trivalent terbium ion. The dominant emission intensity corresponds to the green color, which depend on the terbium concentration incorporated inside the host matrix.