Thin Film GaN LEDs Using a Patterned Oxide Sacrificial Layer by Chemical Lift-Off Process

摘要

A high-quality GaN-based vertical light-emitting diode (LED) was successfully fabricated and transferred to an electroplated Cu substrate using strip-patterned silicon dioxide $({rm SiO}_{2})$ as a sacrificial layer in a chemical lift-off (CLO) process. The ${rm SiO}_{2}$ strip patterns not only provide the sacrificial structure during the detachment process, but also improve the quality of GaN epilayers through epitaxial lateral overgrowth. Compared with conventional LEDs, the CLO-LEDs have a higher output power and a lower forward voltage. The CLO-LED has a decrease in forward voltage of 0.42 V (at 20 mA) as compared with the conventional LED. In addition, at a drive current of 350 mA, the output power of CLO-LEDs is enhanced ${sim}{2.2}$ fold, compared with that of conventional LEDs.