Journal of Crystal Growth, Vol.337, No.1, 72-80, 2011
Growth and luminescent properties of Lu2SiO5:Ce and (Lu1-xGdx)(2)SiO5:Ce single crystalline films
Single crystalline films (SCF) of Lu2SiO5:Ce (LSO:Ce), (Lu1-xGdx)(2)SiO5:Ce (LGSO:Ce) and LGSO:Ce,Tb orthosilicates with thickness of 2.5-21 mu m were crystallized by liquid phase epitaxy method onto undoped LSO substrates from melt-solution based on PbO-B2O3 flux. The concentration of Gd was varied in the range of x=0.2-0.7 formula units (f.u.). In the case of LGSO:Ce SCF growth we do not use any additional doping for reducing the misfit between the SCF and substrate lattices. The luminescence and scintillation properties of LSO:Ce, LGSO:Ce and LGSO:Ce,Tb SCFs were mutually compared and confronted with the performance of reference LSO:Ce and LYSO:Ce crystals. With increasing Gd content the luminescence spectrum of LGSO:Ce SCF is gradually red-shifted with respect to that of LSO:Ce SCF. The LY of (Lu1-xGdx)SO:Ce SCF becomes lower in comparison with that for LSO:Ce SC at increasing Gd content in the range of x=0.2-0.7 f.u. The peculiarities of luminescence properties of LSO:Ce and LGSO:Ce SCFs in comparison with crystal analogs are explained by the different distribution of Ce3+ over Lu1 and Lu2 positions of LSO host and by the influence of Pb2+ contamination coming from the flux used for the film growth. (C) 2011 Elsevier B.V. All rights reserved.
Keywords:Luminescence;Single crystalline films;Liquid phase epitaxy;Scintillators;Orthosilicates;Ce3+ dopant