In situ controlled reactions and phase formation of thin films on GaAs Available to Purchase

In situ sequential depositions and reactions are used to control a reaction sequence first to consume GaAs and then to release GaAs from the reaction product. The first reaction involves annealing in situ deposited Ni on molecular beam epitaxially grown GaAs (100) at 300 °C to form a $Ni3GaAs/GaAs$ structure. Exposure of this structure to $As4$ results in a reaction which consumes the $Ni3GaAs$ by the layer-by-layer formation of NiAs at the surface and epitaxially regrown GaAs at the $Ni3GaAs/GaAs$ interface. The NiAs formation and GaAs regrowth are controlled by the $As4$ flux. Ni diffusion dominates both the $Ni3GaAs$ formation and decomposition mechanisms. Reflection high-energy electron diffraction, Rutherford backscattering, x-ray diffraction, and transmission electron microscopy data are used to confirm the phase formation and reaction sequences.