Growth of InP on GaAs (001) by hydrogen-assisted low-temperature solid-source molecular beam epitaxy

摘要

Direct heteroepitaxial growth of InP layers on GaAs (001) wafers has been performed by solid-source molecular beam epitaxy assisted by monoatomic hydrogen (H~*). The epitaxial growth has been carried out using a two-step method: for the initial stage of growth the temperature was as low as 200 ℃ and different doses of H~* were used; after this, the growth proceeded without H~* while the temperature was increased slowly with time. The incorporation of H~* drastically increased the critical layer thickness observed by reflection high-energy electron diffraction; it also caused a slight increase in the luminescence at room temperature, while it also drastically changed the low-temperature luminescence related to the presence of stoichiometric defects. The samples were processed by rapid thermal annealing. The annealing improved the crystalline quality of the InP layers measured by high-resolution x-ray diffraction, but did not affect their luminescent behavior significantly.