High-performance and current crowding-free InGaN-GaN-based LEDs integrated by an electrically-reverse-connected Schottky diode and a Mg-delta doped p-GaN

Abstract

This work demonstrates high-performance and current crowding-free InGaN/GaN light-emitting diodes (LEDs) using an electrically-reverse-connected Schottky diode (SD) and an Mg-delta (δ) doped layer. Possible mechanism of carrier transport at the interface between transparent conducting electrode (TCE) and p-GaN with the δ-doped layer is also investigated. Results show that the LED with the SD and Mg delta (δ)-doping layer yields lower series resistance, higher output power, and lower reverse leakage current compared to normal LEDs. In addition, unlike the normal LED, there is no occurrence for the current crowding effect in the proposed LED even at high current density of 380 mA/cm². These remarkable behaviours clearly indicate that the use of the SD and δ-doping in the p-GaN region is very promising to achieve high-brightness and excellent-reliability GaN-based LEDs.

Keywords

GaN / light-emitting diode (LED) / Schottky diode (SD) / integration / current crowding

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Acknowledgements

This work was supported in part by the Ministry of Knowledge & Economy (MKE) through the industrial infrastructure program for fundamental technologies (No. 10033630) and through the part and material development program (No. 211C000553).

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg