Oriented growth and luminescence of ZnO:Eu films prepared by sol-gel process

A series of Eu3+-doped ZnO films have been prepared by a sol-gel method. These films were characterized by X-ray diffraction (XRD) and photoluminecent spectra (PL). Effects of synthetic parameters, such as annealing atmosphere, temperature and concentration of doped ions, on the highly oriented crystal growth were studied in detail. The crystalline structures of films annealed in vacuum have a wurtzite symmetry with highly c-axis orientation. A characteristic 5D0→7FJ (J= 1, 2, 3 and 4) red emission is observed due to energy transfer from the ZnO host to the doped Eu3+ in the c-oriented ZnO films.