Temperature and Recombination Lifetime Effects on Amorphous Silicon Quantum Dot’s Light Emitting Diodes

The internal quantum efficiency of amorphous silicon quantum dots (a-Si DQs, has been studied theoretically as a function of temperature and recombination lifetime of excited carriers. The increase in the internal quantum efficiency with decreasing QD size was attributed to the quantum confinement effects in a-Si QDs. This type of confinement has changed the optical energy gap of the material from indirect to nearly direct transition structure. It is found that the visible-light emission from a-Si QDs is most efficient at room temperature, and the efficiency increases with temperature and decreases with increasing recombination lifetime. Keywords: Nano-LED, Quantum dots, a-Si, Quantum confinement