Improvement of Electrostatic Discharge Characteristics and Optical Properties of GaN-Based Light-Emitting Diodes

Abstract

To improve the positive-and negative-voltage electrostatic discharge (ESD) characteristics of GaN light-emitting diodes (LEDs), an air gap was introduced as an ESD protection structure in an Al film on the bottom side of a sapphire substrate. The negative-voltage ESD characteristic of GaN LEDs with an air gap was remarkably improved from −0.3 to −4 kV. The degradation of electroluminescent intensity of GaN LEDs, which was caused by ESD stress, was also suppressed by an air gap in GaN LEDs. An ESD-stress-induced current is believed to flow in an air gap to protect the multiquantum well of GaN LEDs.

Robust ESD protection for high brightness GaN LEDs using new TVS Zener diodes

“…GaN-based LEDs need special protection to maintain normal functions under frequent electrical shocks such as electrostatic discharge/electrical overstress (ESD/EOS). Their ESD robustness is limited to extremely low levels of 0.3∼4 kV [1][2][3]. Such weakness originates from unavoidable crystalline defects present inside the III-nitride epitaxial films.…”

“…Therefore, a transient voltage suppression (TVS) grade Zener device seems to be essential in order to upgrade the ESD robustness and voltage clamping capability. Likewise, it is important to evaluate 3 Author to whom any correspondence should be addressed.…”