Growth of thin $AlInN∕GaInN$ quantum wells for applications to high-speed intersubband devices at telecommunication wavelengths Available to Purchase

In this article, we report on growth of $AlInN∕GaInN$ multi-quantum-wells (MQWs) with high Al content (93%) by rf-plasma-assisted molecular-beam epitaxy on (0001) GaN/sapphire templates and on bulk GaN crystals. A series of samples with a barrier thickness of $3nm$ and with different well thicknesses of $1.5–3nm$ was grown. The wells were doped with Si at a concentration of $5×1019cm−3$⁠. Structures grown on (0001) GaN-based substrates are crack-free, as demonstrated by Nomarski contrast and scanning electron microscopy measurements. X-ray diffraction mapping of $a$ and $c$ lattice parameters shows that $AlInN∕GaInN$ MQWs are fully strained and have up to 7% indium in the barriers and up to 10% In in the quantum wells. These structures exhibit intersubband absorptions at room temperature at a wavelength in the range of $2.45–1.52μm$⁠. The $AlInN∕GaInN$ strain-compensated MQW structures, having good quality, are very attractive for ultrahigh-bit-rate telecommunication applications at $1.55μm$ wavelengths. In addition, because of their low average refractive index, they could be used as thick cladding layers for optical waveguides.