A study was made of the luminescence of Ce- and Cl-doped thin films which had been prepared by the co-evaporation of doped SrS and elemental Se. From spectrum measurements at various S/Se mole ratios and temperatures, it was found that the relative intensity of the green emission band to the blue emission band decreased with increasing lattice constant. This was quantitatively accounted for as being due to non-radiative energy transfer from the emission band of Ce3+ to the absorption band, due to defects which were associated with anion vacancies in the host lattice.

H.Yang, Y.K.Park, S.H.Ju, B.H.Chang: Applied Physics Letters, 1995, 67[1], 70-2