Investigation of the solid-phase epitaxial growth of amorphized GaAs with in-situ and ex-situ electron microscopy

The influence of non-stoichiometry on the solid-phase epitaxial growth of amorphized GaAs has been studied with in-situ Transmission Electron Microscopy (TEM). Ion-implantation has been used to produce microscopic non-stoichiometry via Ga and As implants and macroscopic non-stoichiometry via Ga or As implants. It has been demonstrated that amorphous GaAs recrystallizes into a thin single-crystal layer and a thick heavily twinned layer when annealed at ~260°C. Video images of the recrystallization process have been quantified for the first time to study the velocity of the crystalline/amorphous (c/a)-interface as a function of depth and ion species. Regrowth rates of the single crystal and twinned layers as functions of non-stoichiometry have been measured. The phase transformation is rapid in Ga-rich material. In-situ TEM results are consistent with conventional in-situ Time Resolved Reflectivity, ex-situ Rutherford Backscattering Spectroscopy and Channeling measurements and ex-situ TEM