Monolithically integrated multi-color InGaN/GaN nanopillar light emitting diodes

A lot of works have been done to explore the possibility of integrating multiple colors in one LED chip [1,2,3]. It has great potential in displays, imaging, sensors, and plenty of possible applications. Multi-color nanoLED arrays have been achieved by molecular-beam-epitaxy grown InGaN dot-in-wire structures [1,3] and colloidal quantum dot arrays [2]. However, they requires complicated manufacturing processes that could not be easily adopted for commercial products. Here we reported a scalable fabrication scheme to make monolithically integrated and electrically driven multi-color nanoLED arrays. The InGaN/GaN nanopillars can be easily fabricated from quantum well structures by lithography and dry etching, which are highly compatible to current LED technologies, and the emission wavelength can be tuned by manipulating nanopillar diameter and engineering strain relaxation effect. The proposed structure of multi-color nanoLED arrays is shown in Fig. 1. In addition, the nanopillar structure could improve the emission efficiency [4] and reduce efficiency droop [5]. All these advantages make nanopillars one of the most promising candidate for next-generation light emitting devices.