395 nm Light-Emitting Diode with 647 mW Output Power Realized Using a Double p-Type Aluminum Composition Gradient with Polarization-Induced Hole Doping

Abstract

Three p-type layer structures, i.e. a p-GaN layer, a short-period superlattice (SL) insertion layer, and a polarization-induced hole-doped double-aluminum composition gradient layer, were compared in terms of their performance in 395 nm high-power light-emitting diodes (LEDs). The device with the polarization-induced hole-doped double-aluminum composition gradient layer has an operating voltage of 3.34 V and a wall-plug efficiency of 55.3% under a 350 mA injection current. Moreover, devices with the polarization-induced hole-doped double-aluminum composition gradient layer structure have better optical output power than devices with a short-period SL inserted in p-GaN.

Keywords:

• 395nm LED
• Al composition gradient layer
• superlattice

Additional information

Funding

This project was supported by the National Key R&D Program of China (Grant Nos. 2016YFB0400800), National Natural Science Foundation of China (Grant No. 61634005), and the Key R&D projects of Shaanxi Province (Grant No. 2018ZDCXL-GY-01-07).