![]() ![]() ![]() However, to satisfy industrial requirements, semi-/non-polar LEDs need to be grown on low cost ≥2-inch foreign substrates, such as sapphire or silicon, instead of freestanding semi-/non-polar GaN with their small size and high preparation costs. demonstrated the first EQE >50% which is still one of the best values to date. Yet, among these results, and many more showing reasonable performances, all were obtained from freestanding semi-/non-polar GaN substrates, while only a few mentioned the use of surface patterning to increase light extraction. So far, some remarkable external quantum efficiency (EQE) values have been reported across the purple, the blue and the green wavelength ranges. They offer the possibility to reduce or eliminate polarization-related effects, such as increasing the radiative recombination rate, and mitigating the quantum-confined Stark effect, whilst also providing solutions to efficiency droop and the green gap, two challenging issues of current III-nitride light-emitting diodes (LEDs) grown from c-plane GaN. Semi-polar and non-polar gallium nitride (GaN) crystal orientations have received considerable attention owing to their many potential advantages over the polar orientation of c-plane GaN. Damage to the crystal was reduced by lowering the direct current (DC) bias through a reduction of the RF power and an increase of the ICP power. These conditions were obtained for a small percentage of chlorine (Cl 2) within the Cl 2 + argon (Ar) plasma combined with a low pressure. In contrast, increasing the physical component enables the impact of crystal orientation to be minimized to achieve a circular nanorod profile with inclined sidewalls. ![]() A dominant chemical component is found to have a significant impact on the morphology, being impacted by the polarity of the planes. The impact of gas chemistry, pressure, temperature, radio-frequency (RF) and ICP power and time are explored. In this paper, we investigate the formation and morphology of semi-polar ( 11 2 ¯ 2) and non-polar ( 11 2 ¯ 0) GaN nanorods using inductively coupled plasma (ICP) etching. However, very limited studies of nanotexturing via dry etching have been performed, in comparison to wet etching. The formation of gallium nitride (GaN) semi-polar and non-polar nanostructures is of importance for improving light extraction/absorption of optoelectronic devices, creating optical resonant cavities or reducing the defect density. ![]()
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