Production and Characterization of Quantum Nanostructures of Epitaxial Semiconductors

An experimental study has been performed using RBS and AFM characterization on InP islands grown by MOVPE on GaAs substrate, aiming to understand the influence of the growth parameters on the size distribution of the nanostructures. In the temperature range 580÷650°C the total amount of deposited InP is independent of temperature which, on the contrary, affects the morphology of the growing islands. This work is part of a broader investigation on the feasibility of self organized growth to obtain nanosized semiconductor islands (Quantum Dots) by exploiting the mismatch-induced strain between substrate and epilayer in MOVPE deposition. In particular our data on the islands size are in very good agreement with preliminary indications of analytical and numerical models on the minimization of the total energy of the island-substrate system.