Epitaxy and optical properties of InGaN/GaN multiple quantum wells on GaN hexagonal pyramids template

The InGaN/GaN multiple quantum wells (MQWs) with truncated pyramid structure have been successfully epitaxially grown on the GaN hexagonal pyramids template through a simple and low-cost etch-regrown process. GaN hexagonal pyramids template was contained by a convenient photo-assisted chemical (PAC) etching method. The truncated pyramids are composed of {101¯1¯} and {112¯2} semi-polar facets as well as (0001) polar facet. It was observed that the InGaN/GaN MQWs substantially emitted broad spectrum with multiple peaks by room temperature photoluminescence (PL). The cathodoluminescence of MQWs red-shifts as the location moves from bottom to top on the facets due to the indium diffusion mechanism.