Low-Voltage and High-Brightness AC Thin-Film Electroluminescent Device Prepared by Molecular Beam Epitaxy

High brightness and low-voltage-driven AC thin-film electroluminescent (ACTFEL) devices were prepared by molecular beam epitaxy (MBE) and their EL properties were compared with those of a vacuum deposited (VD) ACTFEL device. From the brightness-voltage curve, a threshold voltage of 45.5 V and a maximum brightness of 523 ft-L (5 kHz, 73.5 V) were obtained. Besides a luminance of 300 ft-L was achieved at 58.5 V when the device was operated with 5 kHz sinusoidal wave. These values were superior to those of a VD-prepared ACTFEL device. Therefore, it was suggested that MBE is one of the most effective techniques to obtain ACTFEL devices with high performances.