Tensile Strained, Type II, GaP/GaAs Nanostructures

We demonstrate the fabrication of self-assembled GaP nanostructures on GaAs (100) substrates by droplet epitaxy using molecular beam epitaxy. The dependency of GaP nanostructural properties on substrate temperature (250-350 degrees C) as droplets are deposited is investigated. The dimension, density, and shape of GaP nanostructures strongly depend on the substrate temperature. It is found that nano-dots are formed when Ga droplets are deposited at 250 degrees C, while ring-shape nanostructures are formed when Ga droplets are deposited at 300 degrees C or higher. Photoluminescence results confirm the high quality of the GaP nanocrystals.