• KIEE International Transactions on Electrophysics and Applications
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• v.4C no.2
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• pp.64-67
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• 2004

In this paper, to discover the brightness improvement of ZnS:Cu powder electroluminescence (EL), a new structure is proposed in which phosphor and dielectric are mixed between electrodes. Dielectric and phosphor material are BaTiO$_3$ and ZnS:Cu, respectively. The effect of the mixed layer on EL sample is considered the improvement of source efficiency. Although the number of electrons introduced into the phosphor increases only modestly, the high electric field region of phosphor grains increases comparatively in the characteristics of brightness-voltage. Furthermore, the relaxation occurs through leading and trailing edge pairs, which is relatively efficient in characteristics of decay time. With these results, we found that the brightness of newly proposed ZnS:Cu powder electroluminescence was 167.24 cd/$m^2$ at ac voltage of 100V and frequency of 400Hz.

• Journal of Sensor Science and Technology
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• v.4 no.4
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• pp.10-15
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• 1995

Organic thin film electroluminescent(EL) cells were fabricated. Their output characteristics and luminance versus voltage characteristics were measured with different work function metal electrodes. The EL structure was Indium-Tin-Oxide(ITO)/hole transport layer/emission layer(electron transport layer)/metal electrode. PMMA+TPD(0.5 wt%), MC homopolymer+TPD(0.005 wt%) and (MC/MMA) copolymer+TPD(0.005 wt%) were used as hole transport layer. Ca, Mg, Mg:Ag(10:l) and Al were used as metal electrode. I-V output showed exponential feature, and the threshold voltage of 5 volts and the luminance of over 700 $Cd/m^{2}$ at 10 volts were observed.