Using Planarized p-GaN Layer to Reduce Electrostatic Discharged Damage in Nitride-Based Light-Emitting Diode

Electrostatic discharge damage is a serious problem on nitride-based light-emitting diodes (LEDs), due to their large lattice mismatch between III–nitride material and the sapphire substrate, which induces high-density threading dislocations. In this study, GaN/GaInN-based LEDs with various thicknesses of the low-temperature planarized p-GaN layer were fabricated. We found that when the V-shaped defects were filled by the planarized p-GaN layer, the survival rate of LEDs under human-body mode -4000 V stress increases from 23 to 93% and the survival rate under machine mode -600 V stress increases from 20 to 67%. Thus the ability to endure higher electrostatic discharge stress will be greatly improved.