Blocking effect in electroluminescence of ZnS:Mn driven by short voltage pulses

Abstract

Electroluminescent thin film cells based on luminescent active ZnS:Mn layers are investigated. Untypical behaviour of the electroluminescence compared to direct excitation luminescence is observed when the cells are excited by short voltage pulses of about 10 μs. The model of energy transfer between two monomolecular centres is taken into account to explain this phenomenon. On the base of this model, a relation describing the time dependence of luminescence during the exciting pulse is obtained. It is shown that the relation is in good agreement with experimental data.

Spectral and kinetic properties of electroluminescence of ZnS:Cu powder in polymer structure

“…The authors found that at low excitation frequency the green emission is more intense, while over 1 kHz the blue band predominates over the green one. In the light of In the luminescence investigations, kinetic measurements are very important because they provide much information concerning the luminescent centers and the mechanism of luminescence in general [8][9][10][11][12]. Especially important are the measurements of luminescence excited by a constant pulse, for example, voltage, during as well as after the end of the pulse [9][10][11][12].…”

“…In the light of In the luminescence investigations, kinetic measurements are very important because they provide much information concerning the luminescent centers and the mechanism of luminescence in general [8][9][10][11][12]. Especially important are the measurements of luminescence excited by a constant pulse, for example, voltage, during as well as after the end of the pulse [9][10][11][12]. Figure 3 shows the time dependence of luminescence of the structure investigated during and after the end of the voltage pulse of 75 V, 1 ms. As is seen in the figure, the electroluminescence quickly attains its maximum and then subsequently decays during as well as after the voltage pulse.…”

Integrated light in direct excitation and energy transfer luminescence

“…For example, Chimczak et al (1984Chimczak et al ( , 1995 described theoretically very well time dependence of ZnS:Mn electroluminescence of thin film devices excited by short voltage pulse 1,2 . The researches (1989) have also obtained good fitting of the electroluminescence to the experimental data during 3 as well as after the end 4 of rectangular exciting pulse. obtained very good description of emission of Tb 3+ in CsCdBr 3 : Tb 3+ upon excitation in 5 D 3 level at 1.3 and 75 K 5 .…”

“…However, contrary to the spectral measurements, the kinetic measurements allows very often to give a quantitative description of the dependence investigated permitting the better determination of the mechanism of luminescence and, for example, electroluminescent device. Therefore, many papers are devoted to kinetic of luminescence 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31 . Some investigators have established correlated formulas to describe the time dependence of luminescence.…”