Electrical and optical properties of laser irradiation treated vertical light-emitting diodes
A comparative analysis of the properties of vertical light-emitting diodes (VLEDs) fabricated using different surface treatment schemes was conducted. Compared with a conventional VLED, a light output power increase of 24.8% for an injection current of 350 mA was achieved by an n-type-gallium nitride (GaN)-based VLED with a thin undoped GaN layer and microsized protrusions produced by krypton fluoride laser irradiation using an energy density of 600 mJ/cm2. This was accomplished without noticeable degradation of the electrical properties of the device. Further, potassium hydroxide wet etching of the VLED surface increased the light output power gain to 47.3% for the same injection current.