Determination of the spectrum of trapping levels in thin-film electroluminescent capacitors based on ZnS:Mn

This paper investigates trapping levels in thin-film electroluminescent capacitors based on ZnS:Mn. The authors started from the well-known fact that the electrons stored in the trapping levels can give an electroluminescent flash at voltages below threshold levels, i.e., insufficient for creating stationary emission. The investigations were carried out on a thin Mn-doped ZnS film confined between two dielectric layers of Y2O3. By studying the dependence of the emitted light sum on the holding time after excitation with an LGI-21 laser at different fixed temperatures, it was possible to determine the thermal ionization energy of the trapping centers. It was also possible to distinguish four types of levels with levels of 0.26, 0.4, 0.57, and 1.23 eV