Mn-activated Zn 2 SiO 4 and Ce-activated Y 2 SiO 5 multilayer thin film electroluminescent ͑EL͒ devices were prepared by rf magnetron sputtering. The EL response of the devices under different voltages, frequencies, and pulse widths, as well as the transferred charge and decay characteristics were studied. The EL device using Zn 2 SiO 4 :Mn as the phosphor layer is shown to achieve a brightness of over 200 cd/m 2 at 400 Hz and a field of 3ϫ10 6 V/cm ͑twice the threshold field͒ and a maximum efficiency of 0.78 lm/W, with a decay time of 0.6 ms. The main characteristics of the oxide phosphors include ͑a͒ strong trailing edge excitation in nonsymmetrical EL devices, ͑b͒ a narrow transferred charge loop, and ͑c͒ a time response sensitive to device structures. Compared with the nonsymmetrical structure, the more symmetrical double-insulated structure is shown to increase the efficiency of the EL device by generating strong EL excitation from both positive and negative voltage pulses.

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