Chemical Lift-Off Process for Blue Light-Emitting Diodes

摘要

An epitaxial layer of an InGaN light-emitting diode (LED) structure was separated from a truncated-triangle-striped patterned-sapphire substrate through a chemical lift-off (CLO) process. A crystallographic stable and terminated V-shaped GaN grooved pattern was observed on the lift-off GaN surface. A peak wavelength blueshift phenomenon of the micro-photoluminescence spectrum was observed on the lift-off LED epitaxial layer (440.7 nm) compared with the LED/sapphire structure (445.8 nm). The free-standing LED epitaxial layer with a 453 nm electroluminescence emission spectrum was realized through a CLO process with the potential to replace the traditional laser lift-off process for vertical LED applications.