Tunneling Enhanced Structure for Improving the Performance of Ultraviolet Light-emitting Diodes

Abstract

The novel AlGaN-based ultraviolet light-emitting diode (UV-LED) with a tunneling enhancement structure is proposed. The tunneling enhanced structure consists of an ITO layer, an extremely thin AlN layer, and a p+-GaN layer. Under forward bias, compared to traditional devices, tunneling enhanced UV-LEDs can shorten the width of the tunneling region. In addition, the dielectric constant of the AlN layer in the tunnel area is small, which can effectively increase the transport of holes from the ITO layer to the MQWs active region. Due to the increased hole concentration and drift speed, for a 300 ㎛ × 254 ㎛ UV-LED chip, the optical output power increased by 19.6% at 120 ㎃. Therefore, the proposed tunneling enhanced structure provides a simple and effective way to increase the light output power of UV-LEDs.