Significant improvement of luminance and stability of a red electroluminescent device using nanocrystalline silicon

An electroluminescent (EL) device using nanocrystalline silicon (nc-Si) was fabricated by annealing after cosputtering of Si chips and silicon dioxide target and subsequent hydrofluoric acid solution treatment. The device emitted a red light with a peak at 670 nm by applying a low direct current (DC) operating voltage of 4.5 V. The external quantum efficiency (EQE) of red luminescence at 4.5 V was 0.35%. Moreover, the intensity of red luminescence was very stable for an operating time of 15000 min. These results are a strong indication that the HF-treated device can be adapted to future light-related devices.