Investigation of Nitrogen Induced Closely Coupled Sb Based Quantum Dots for Infrared Sensors Application

摘要

We report the growth and structural properties of InSb and InSb:N quantum dots on InAs and GaAs substrates. Strain induced, self-assembled quantum dots are grown using solid-source molecular beam epitaxy. For improved growth control, we developed a growth technique similar to atomic layer epitaxy methods. InSb and InSb:N multiple quantum dots formed on both InAs and GaAs. We explain the formation of multiple quantum dots by the anisotropic distribution of strain energy within the quantum dot, the long adatom lifetime during atomic layer epitaxy, and the low bond energy of InSb. Nitrogen incorporation during formation of quantum dots changes the surface energy barrier and causes an anisotropic distribution of strain energy, results in the formation of closely coupled multiple quantum dots in the <110> orientation. We obtained mid infrared luminescence around 3.6μm from InNSb QDs grown on InAs substrate, where it exhibits relatively low nitrogen incorporation efficiencies compared to the quantum well structure.