Characteristics of InGaN/GaN light-emitting diode with Si delta-doped GaN contact layer

Abstract

We have investigated the characteristics of InGaN/GaN blue, light-emitting diodes (LEDs) with a Si delta -doped GaN contact layer. The Si delta -doping of the GaN contact layer in the devices could enhance the Si doping concentration and improve the lateral conductivity in the GaN:Si contact layer without cracking. The operating voltage and dynamic resistance of LEDs with a Si delta -doped GaN contact layer were 3.65 V and 27 Ohm at 20 mA, respectively. The operating voltage, and dynamic resistance of conventional LEDs with a uniformly doped GaN:Si contact layer were 3.94 V and 32.3 Ohm at 20 mA, respectively. Also, the leakage currents at a reverse bias of - 10 V were 2.8 muA for delta -doped LEDs and 29 muA for uniformly doped LEDs. However emission properties such as electroluminescence spectra and output power were not largely affected by utilizing a delta -doped GaN:Si contact layer in the devices.