Room temperature green light emission from nonpolar cubic InGaN∕GaN multi-quantum-wells

Abstract

Cubic $\mathrm{In}\mathrm{Ga}\mathrm{N}∕\mathrm{Ga}\mathrm{N}$ multi-quantum-wells (MQWs) with high structural and optical quality are achieved by utilizing freestanding $3C\text{-}\mathrm{Si}\mathrm{C}$ (001) substrates and optimizing InGaN quantum well growth. Superlattice peaks up to fifth order are clearly resolved in x-ray diffraction. Bright green room temperature photoluminescence (PL) from $c\text{-}{\mathrm{In}}_x{\mathrm{Ga}}_{1-x}\mathrm{N}∕\mathrm{Ga}\mathrm{N}$ MQWs $(x=0.16)$ is observed. The full width at half maximum of the PL emission is about $240\mathrm{meV}$ at $300\mathrm{K}$ . The PL intensity increases with well thickness, prooving that polarization fields which can limit the performance of the wurtzite III-nitride based devices are absent. The diffusion length of excess carriers is about $17\mathrm{nm}$ .