Probe layer measurements of electroluminescence excitation in ac thin-film devices

Abstract

It is found that Mn electroluminescence (EL) efficieny varies widely with the position of a Mn-doped probe layer in a double dielectric thin-film ZnS ac EL device. TbF3-and Ag-doped layers exhibit a more uniform EL efficiency. The results are consistent with impact excitation of Mn in an electric field that varies in the ZnS due to space charge. The more uniform EL efficiency probed in TbF3, in contrast, suggests that the excitation mechanisms of Tb is not primarily by hot-electron impact in our devices.