High-quality AlInN for high index contrast Bragg mirrors lattice matched to GaN

Abstract

We report on the growth by metalorganic vapor phase epitaxy of high-quality ${\mathrm{Al}}_{\text{1−x}}{\mathrm{In}}_x\mathrm{N}$ layers and AlInN/GaN Bragg mirrors near lattice matched to GaN. Layers are grown on a GaN buffer layer with no cracks over full 2 in. sapphire wafers. The index contrast relative to GaN is around 7% for wavelengths ranging from 950 to 450 nm. We demonstrate the growth of a crack-free, 20 pairs ${\mathrm{Al}}_{\text{0.84}}{\mathrm{In}}_{\text{0.16}}\mathrm{N/GaN}$ distributed Bragg reflector centered at 515 nm with an over 90% reflectivity and a 35 nm stop band. The growth of high quality AlInN lattice matched to GaN may represent a breakthrough in GaN-based optoelectronics which is presently limited by the lack of a high-index-contrast and high-band gap lattice-matched material.