We fabricated InGaN/GaN nanorod light emitting diode (LED) on (-201) β-Ga₂O₃ substrate via the SiO₂ nanosphere lithography and dry-etching techniques. The InGaN/GaN nanorod LED grown on β-Ga₂O₃ can effectively suppress quantum confined Stark effect (QCSE) compared to planar LED on account of the strain relaxation. With the enhancement of excitation power density, the photoluminescence (PL) peak shows a large blue-shift for the planar LED, while for the nanorod LED, the peak position shift is small. Furthermore, the simulations also show that the light extraction efficiency (LEE) of the nanorod LED is approximately seven times as high as that of the planar LED. Obviously, the InGaN/GaN/β-Ga₂O₃ nanorod LED is conducive to improving the optical performance relative to planar LED, and the present work may lay the groundwork for future development of the GaN-based vertical light emitting diodes (VLEDs) on β-Ga₂O₃ substrate.

We fabricated the dual-wavelength InxGa1−xN/GaN nanorods for wide-spectrum light-emitting diodes (LEDs) by silica nanosphere lithography (SNL) technique. The emission properties of the dual-wavelength nanorods are characterized by micro-photoluminescence (micro-PL), cathodoluminescence (CL), and temperature-dependent PL (TDPL) measurements. Nanorod structure can effectively suppress quantum confined Stark effect (QCSE) compared with planar structure due to the strain relaxation. In addition, the internal quantum efficiency (IQE) of the green quantum well (QW) within nanorod structure increases, but the IQE of the blue QW clearly decreases because blue QW has severely suffered from the nonradiative recombination by surface damage. Furthermore, the IQEs of the green QW and the blue QW within the nanorod structure can be effectively improved by wet etching treatment, with an increase in factor by 1.3 when compared with unetched nanorod structure. Evidently, the dual-wavelength InxGa1−xN/GaN nanorods are beneficial to improve the optical performance compared with planar structure, presenting a potential to realize monolithic, high-efficiency, and cost-effective white LEDs.