Al₂O₃Powder Coating and Surface Texturing for High Efficiency GaN-Based Light Emitting Diodes

Abstract

For high efficiency GaN-based light-emitting diodes (LEDs), Al 2 O 3 powder coating and surface texturing were investigated using natural lithography and dry-etching methods to improve the light-output power of the GaN-based LED. The 300-nm-size Al 2 O 3 powder is coated on the indium tin oxide (ITO) surface at various conditions using a spin-coating method. The morphologies of the ITO surface were observed using a scanning electron microscope. The Al 2 O 3 powder is left on the ITO surface after surface-texturing to increase extraction efficiency. The light output powers of the surface-textured GaN-based LEDs coated with the Al 2 O 3 powders are enhanced by 66% compared with the conventional LED at 20 mA.

Transparent gold nano-membranes for the enhanced light trapping of the indium tin oxide films

“…A variety of methods have been reported for creating textured structures on ITO films. One typical way is to dry-etch the ITO films by inductively coupled plasma with an etching mask [11,[13][14][15][16]. However, this method includes high-cost, toxic equipment and complex processes.…”

Enhancement in the Light Output Power of GaN-Based Light-Emitting Diodes with Nanotextured Indium Tin Oxide Layer Using Self-Assembled Cesium Chloride Nanospheres

“…5) Recently, extensive research has focused on the use of a roughened indium tin oxide (ITO) surface to improve the performance of LEDs. [13][14][15][16][17] However, some of these techniques need either nanoimprinting equipment or an electronic beam lithography (EBL) system, which are considered to be too complex and costly to be applied in commercial production. In addition, some methods cannot provide a wafer-level uniform rough surface.…”