Extremely high breakdown voltage in high-brightness InGaN LEDs

High-brightness InGaN light emitting diodes (LEDs) with an output power of 2.7, 2.3, and 1.8 mW at a driving current of 20 mA for the emitting wavelength of 470, 505, and 525 nm, respectively, were realized using metalorganic vapor phase epitaxy. The I-V characteristic of these devices experiences a reverse-bias voltage higher than 60 V for a leak current of 10 μA. We find out that the dislocation density in the n-GaN layer is crucial to achieve such high breakdown voltage. By varying growth parameters, we can tune the breakdown voltage from 10 V to 60 V.