Fabrication of vertical AlGaN-based deep-ultraviolet light-emitting diodes operating at high current density (∼43 kA cm−2) using a laser liftoff method

We have successfully fabricated vertical LEDs by separating a 1 × 1 cm 2 wafer composed of deep-ultraviolet LED on a sapphire substrate from the substrate using a laser liftoff (LLO) method. Reproducible substrate separation was achieved by the LLO method using an Al 0.68 Ga 0.32 N underlayer film on an AlN template with periodic pillars. The fabricated vertical LED successfully demonstrated notable luminescence (peak wavelength: 298 nm) characteristics up to a current density of ∼43 kA cm −2 at room temperature and in pulsed drive, which is expected to be used in high-power LEDs and laser diodes.