Low frequency noise characterization of the GaN LEDs

The aging of the GaN LEDs was investigated by low frequency noise characterization at different biasing conditions. Two components of the i/fnoise, which are related to the junction and contact noise sources, were observed. It was found that the contact noise source in the thermally aged LEDs exhibits higher fluctuations than in the virgin devices. This difference in noise characteristics could be used as reliability indicator of the GaN LEDs.