Raman scattering studies of InP nanostructures created by MeV Sb ion implantation

We have investigated the nanostructures created via MeV implantations by utilizing the techniques of Raman scattering and scanning probe microscope (SPM). SPM demonstrates that a large number of nanostructures are smaller than 100 nm in size and lower than 4 nm in height. SPM and Raman scattering techniques have been combined to show that although InP surfaces initially become rougher with increasing fluence, they become smoother after critical fluence when the crystalline/amorphous phase transition takes place. Raman spectroscopy further suggests an increase in tensile stress on the InP surface with increasing ion fluences. Phonon confinement model (PCM) has been applied to investigate the correlation length of the crystalline nano-zones in the InP lattice. Results indicate that crystalline nano-zones of 35 angstrom may be embedded in the InP lattice at high fluences.