Fabrication of InGaN light-emitting diodes with embedded air-gap disks using laser-drilling and electrochemical processes

InGaN-based light-emitting diodes (LED) with an embedded air-gap disk structure were fabricated using a laser drilling process and an electrochemical (EC) wet etching process. The disk-shaped air-gap structure was formed surrounding the laser-drilled hole as a reflective structure to enhance the light extraction efficiency. The light output power of the treated LED structure was enhanced by 22% compared with a conventional LED at 20 mA. High light emission intensity of the treated LED structure was observed at the 40-μm-diameter embedded air-disk patterns in the mesa region. The InGaN LED structures with the laser-drilling holes and embedded air-disks can reduce the light trapping effect and increase the light extraction efficiency in the device's central mesa region.