Fabrication of InGaN/GaN MQW nano‐LEDs by hydrogen‐environment anisotropic thermal etching

III‐nitride semiconductor nanostructures are attractive materials for the realization of high‐performance and highly functional optoelectronic devices. In this study, we fabricated InGaN/GaN multiple quantum well (MQW) nanostructured light‐emitting diodes (nano‐LEDs) using hydrogen‐environment anisotropic thermal etching (HEATE). HEATE is a low‐damage anisotropic etching technique that is based on the thermal decomposition of (In)GaN under a low‐pressure hydrogen environment. The InGaN/GaN MQW nano‐LEDs showed good rectification characteristics and blue emission without any post treatment to remove all etching damage. The narrowest MQW lateral sizes of successfully fabricated nanowall and nanopillar LEDs were 87 and 70 nm, respectively. These LEDs are among the smallest InGaN/GaN‐based nano‐LEDs fabricated via a top–down process. Electroluminescence images of InGaN/GaN nano‐LEDs operated at 3 V. (a) An a ‐axis honeycomb nanowall, (b) an m ‐axis nanowall array, (c) an a ‐axis nanowall array, and (d) a nanopillar array.