Green photoluminescence from Zn_3N_2:Tb films prepared by magnetron sputtering

摘要

Terbium (Tb)-doped Zn_3N_2 thin films were prepared on glass and Si substrates by direct current magnetron sputtering in a mixture of pure argon and nitrogen gases. Glancing incidence x-ray diffraction patterns indicated that Zn_3N_2:Tb thin films were of cubic structure. Raman spectra showed only two Raman-active phonon modes located at 258 and 565 cm~(-1). The indirect optical band gap of Zn_3N_2:Tb was determined as 2.4 eV. The sharp characteristic emission lines corresponding to Tb~(3+) intra-4/ shell transitions were resolved in the photoluminescence spectra at room temperature. Those results suggest that Tb-doped Zn_3N_2 may be a suitable material for visible optoelectronic devices.