Near-infrared light emitting diode array based on ordered Si micropillar/InGaZnO-nanofilm heterojunctions

A novel near-infrared light emitting diode (LED) array based on ordered Si micropillar/InGaZnO-nanofilm heterojunctions was proposed and demonstrated. The pixel resolution of the LED array is 4,885 dpi, corresponding to a pixel pitch of 5.2μm. The fabricated LED array shows good rectification characteristics with small serial resistance. Carrier transport obeys the trap-charge-limited current model. The electroluminescence emission peaks of this LED device are in the near-infrared region, which attribute to the deep defect level Vo in the InGaZnO film and interface traps in the Si-SiO₂ interface, respectively. These results provide important supplementary for Si-based light emitting devices.