ELECTRICAL AND OPTICAL STIMULATION OF LUMINESCENCE IN CA1-XCDXS

Mixtures of CaS and CdS treated at 1020-degrees-C for 2 h in a nitrogen atmosphere with an excess sulphur pressure have resulted in solid solutions, Ca1-xCdxS up to x = 0.41. Fluorescence emission studies have indicated massively enhanced broad band emission spectra for x between 0.01 and 0.10 at both 77 and 300 K. Electroluminescence studies of copper-coated powder-based samples under AC excitation conditions at x = 0.05 have indicated significant emission intensities broadly aligned spectrally with those from photo-stimulation at the same composition. Further investigations are being directed at optimization of composition, particle size, layer thickness and excitation conditions for enhanced electroluminescence emission intensities.