Klemens Hitzbleck

Gaas whiskers grown by metal-organic vapor-phase epitaxy using Fe nanoparticles

GaAs nanowhiskers were grown by metal-organic vapor-phase epitaxy on (111)B GaAs substrates. The diameter of the nanowhiskers was defined by monodisperse Fe nanoparticles deposited on the GaAs substrate from the vapor phase. The growth temperature of the whiskers was investigated from 480to520°C. The whiskers are preferentially directed along the crystal orientations of ⟨001⟩, ⟨111⟩, and their equivalents. High-resolution transmission electron microscopy characterization including energy disperse x-ray spectroscopy measurements revealed not only iron oxide but also arsenic inside the seed particle at the top of the GaAs whiskers. This indicates that the particle stays at the top during the whisker growth.

Controlled formation and size-selected deposition of indium nanoparticles from a microwave flow reactor on semiconductor surfaces

Indium nanoparticles were synthesized in a microwave flow reactor by thermal decomposition of trimethylindium. The particles were extracted from the gas phase by molecular beam sampling, deflected in an electric field, and deposited on a semiconductor surface. The size of the deposited particles was selected by adjusting the deflection voltage. The geometric standard deviation of the size-selected particles was found to be smaller than 10%. The deposition method is compatible with epitaxial growth methods and enhances their potentials with nanoparticle technology.